Hair Loss Causes and Treatments
Alopecia areata (Fig 2.3.8 5.) is disease of unknown etiology that results in nonscarring alopecia. Clinically, one will loose round patches of hair leaving behind smooth bald skin. Inflammation or scale is not present. Any hair-bearing area may be affected, but the scalp is the most common site of involvement. Rarely, patients loose all of their scalp or body hair these are referred to as alopecia totalis and alopecia universalis, respectively. Diagnosis is based on clinical examination. Exclamation point hairs may be noted at the periphery. Alopecia areata may be associated with hyperthyroidism thus, checking a TSH is warranted. Secondary syphilis may result in patchy alopecia described as moth-eaten alopecia. Often, scale is present. If secondary syphilis is suspected by history, a screening test, such as an RPR or VDRL, should be performed. Patients should be counseled that localized alopecia areata usually resolves spontaneously within two to six months. Extensive disease is less...
There is a tendency for scales that are very sensitive to change to amplify statistically significant changes that may be clinically irrelevant. Take for example the trial of 2 minoxidil against placebo for androgenetic alopecia in women.14 This study found a statistically significant increase in non-vellus target area hairs in the minoxidil-treated group versus the vehicle-treated group after 32 weeks (P 0-006) although the subjects discerned no difference . The study, which was otherwise well conducted, should have concluded something along the lines of, something seems to be happening, but it is not clinically useful yet . However, the authors' conclusion was that, Two per cent minoxidil appears to be effective in the treatment of female androgenetic alopecia . Effective for whom
Chronic peripheral arterial insufficiency is characterized by intermittent claudication, which may progress to intermittent ischemic pain at rest. Femoral and popliteal disease often causes reproducible calf pain with activity that is relieved with rest. Pain at rest typically localizes to the foot and is aggravated with leg elevation, improves with standing, and is poorly controlled with analgesics.11 Shiny, hyperpigmented skin with hair loss and ulceration, thickened nails, muscle atrophy, vascular bruits, and poor pulses is a hallmark of chronic vascular disease. Complete arterial occlusion from thrombosis of a limb in these patients may present subacutely owing to a well-developed collateral circulation.
Cowden syndrome displays a high level of variability in expression, both between and within families however, it usually presents in the third decade. Hamartomas are derived from all three germ cell layers. Those of the inner organs most commonly involve the breast (70 ) thyroid adenomas and multinodular goitres (40-60 ) gastrointestinal polyps (35-40 ) and can also be seen in the central nervous system and reproductive tract. The gastrointestinal polyps seen in CS are distinct from those seen in other hamartomatous syndromes, as they are more likely to be of ectodermal and or endodermal origin. 5 Dermatological manifestations are the most prevalent findings, with palmoplantar hyperkeratosis in 54 , trichilemmonmas (benign tumors of the hair follicle
The pluripotential cells that give rise to these tumors may differentiate into four basic groups hair follicle, eccrine gland, apocrine gland, and sebaceous gland (26,27). The degree of differentiation is established according to the resemblance of the tumor cells to the normal structures. Hyperplasias are composed of mature elements, almost identical to normal tissue, but increased in number. Adenomas are less differentiated but mature glandular or follicular structures are identified. In epitheliomas, the degree of differentiation is even less, and it is hard to identify the type of structures that the tumor is forming. Sweat gland origin is suggested by positive immunohistochemical (IHC) stains to carcinoembrionic antigen (CEA), epithelial membrane antigen (EMA), cytokeratins (CK), and gross cystic disease fluid protein (GCDFP-15).
(short sequences repeated thousands of times in tandem), which are common in the genomes of higher eukaryotes (see Fig. 24-8). The number of repeated units in these DNA regions varies among individuals (except between identical twins). With a suitable probe, the pattern of bands produced by DNA fingerprinting is distinctive for each individual. Combining the use of several probes makes the test so selective that it can positively identify a single individual in the entire human population. However, the Southern blot procedure requires relatively fresh DNA samples and larger amounts of DNA than are generally present at a crime scene. RFLP analysis sensitivity is augmented by using PCR (see Fig. 9-16a) to amplify vanishingly small amounts of DNA. This allows investigators to obtain DNA fingerprints from a single hair follicle, a drop of blood, a small semen sample from a rape victim, or samples that might be months or even many years old.
Fuzzy set logic theory refers to a generalized concept of a logical set in which the elements have continuously graded degrees of set membership that range from the values 0 to 1 (rather than either belonging or not belonging to the set as in conventional set theory). Fuzzy logic is a form of algebra useful in drawing conclusions from insufficient, imprecise, or conflicting data sets and, presumably, mimics the way in which the brain arrives at conclusions. Fuzzy set theory was first proposed by the Azerbaijanian systems theorist computer scientist Lofti A. Zadeh (1921- ) in 1965, and was used, initially, to demonstrate that many natural characteristics (such as height, baldness, beauty) contain indistinct and undiffer-entiated boundary lines. The notions of guppy effect and prototype theory indicate potential areas of weakness for fuzzy set theory. The guppy effect (described by the American psychologists D. N. Osherson and E. E. Smith in 1981) refers to an...
Clonal, or asexual, reproduction, in nature results in nearly genetically identical individuals. This includes two categories of genetic identity between parent and offspring, and among offspring. However, for numerous traits, genetic identity does not result in phenotypic identity, either due to epigenetic effects or to environmental effects. The environmental effects are well known, particularly from human identical-twin studies. Epigenetic effects are defined as effects due to genes that vary from organism to organism due to random chance, and therefore, cannot ever be predicted exactly. Epigenetic effects are less well known than environmental effects, but can be huge for some traits, such as different coat-color patterns among clones or identical twins. There is no genetic instruction specifying the color of each individual hair in animals with hair of different colors, but only genetic instructions for the general pattern of hair color. These instructions provide general...
The flea, Ctenocephalides felis, is the most common ectoparasite of the cat in the UK. The term 'flea-bite hypersensitivity' is used to describe the clinical condition seen in animals that have become sensitised to antigenic components of flea saliva. The immuno-pathogenesis of the condition in the dog is thought to involve both type I and type IV hypersensitivity reactions, with a late-onset immunoglobulin E (IgE) and cutaneous basophil response similar mechanisms have been proposed for the cat. In many cases this reaction manifests clinically as pruritus and secondary self-trauma, leading to symmetrical alopecia of the ventral abdomen, dorsum and tailhead region (Plate 6.1). Other clinical syndromes associated with flea-bite hypersensitivity in the cat are papulocrusting (miliary) dermatitis and eosinophilic granuloma complex. The haematophagous activities of the fleas, females in particular, can lead to life-threatening anaemia for kittens with heavy infestations.
Skin is a complex tissue made of a structured combination of cell types. It has an enormous regenerative capacity and contains several different kinds of stem cells (SCs). Fundamental differences likely exist between embryonic skin stem cells and adult skin stem cells. In this chapter we focus on epithelial skin stem cells (ESSCs) in postnatal mouse skin. Nonhuman studies allow for high flexibility and increased depth of study and are less restricted by ethical issues. ESSCs are thought to reside in a specialized area of the hair follicle called the bulge. Cells in this compartment possess the ability to differentiate, at least under stress conditions, into different cell lineages to regenerate not only the hair follicle but also the sebaceous gland (SG) and the epidermis. In adult skin, stem cells are thought to be the slow cycling cells that retain Bromo-deoxy-uridine (BrdU) DNA label over long periods of time. How these cells maintain their properties of self-renewal and...
Tinea capitis (scalp ringworm) is an infection of the scalp skin and hair caused by fungi (dermatophyte) mainly of the genera Trichophyton and Microsporum. The clinical hallmark is single or multiple patches of hair loss, sometimes with a black dot pattern (Figure 34.1), which may be accompanied by signs of inflammation such as scaling, pustules and itching.1,2
SLE is considered to be a rare, multisystemic, autoimmune disorder that most frequently involves the musculoskeletal, haematopoietic, cutaneous and urinary systems. Cutaneous manifestations of feline SLE are exceptionally rare and may include generalised alopecia, scaling and crusting, involving the face, pinnae, neck, ventrum and limbs, and crusting of all digital pads. The histological features may include interface dermatitis, interface folliculitis, epidermal basal cell and follicular basal cell vacuolation with necrosis. The immunological basis for the latter changes is thought to involve keratinocyte apoptosis mediated by T-lymphocytes that infiltrate the epidermis evidence for this process is lacking in the cat. In addition, there is often immunohistochemical evidence of immune complex deposition at the basement membrane zone. Glucocorticoid therapy with 4 mg kg per day for 1 month initially was effective in establishing control of one case with a positive ANA titre, oral...
In the PubMed database different search terms were used for male and female androgenetic alopecia. For male androgenetic alopecia the search terms were ((androgenetic and alopecia) or (*male and pattern and baldness)) and (finasteride or minoxidil). For female androgenetic alopecia the search terms were ((female and androgenetic and alopecia) or (female and pattern and baldness)) and (minoxidil or antiandrogen* or cyproteroneacetate or (cyproterone and acetate) or cyproteronacetate or estrogen* or oestrogen* or estradiol). Figure 42.1 Typical male pattern hair loss in a 28-year-old patient Figure 42.1 Typical male pattern hair loss in a 28-year-old patient Which topical or systemic treatment can stop further hair loss and increase hair density in
Other RCTs have demonstrated that finasteride significantly improves the anagen telogen ratio21 and has also positive effects on the frontal hair line.22 On the basis of recently published 5-year data,23 hair loss can be stopped in 90 of men taking finasteride, compared with 25 in the placebo group. In addition to stoppage of hair loss, an increase in hair density was seen in 48 of the men in the finasteride group, compared with 6 of men in the placebo group after 5 years of the study.
The true incidence and prevalence of alopecia areata is unknown. It is estimated that 1-7 of the population will experience an episode of alopecia areata during their lifetime.2 Alopecia areata accounts for 2 of new dermatological outpatient department attendances in the UK and US.3 While alopecia areata can develop at any age, 30-40 of cases appear before 21 years of age and 20-30 after 40 years of age.4 The condition occurs in equal incidence in both sexes. The percentage of patients with alopecia areata that go on to develop alopecia totalis universalis is not known, but estimates range from 7 to 30 .5
Diphencyprone is not licensed in the USA. Immunotherapy for alopecia areata is only available in specialist treatment centres. We found no RCTs on the use of topical immunotherapy however, a number of studies have demonstrated unilateral hair regrowth after unilateral treatment. This protocol conforms to the published investigational guidelines for alopecia areata.14 In almost all case series, patients with limited disease have higher response rates than patients with alopecia totalis universalis. In contrast to other studies, Shapiro et al.22 found that a long duration of disease did not necessarily preclude a positive response to treatment with diphencyprone. Tosti et al. concluded from their work that transferring non-responder patients with alopecia totalis or universalis to other therapies is generally useless.23
The most pressing short-term problems arise out of the fact that the most immediate impact of finished sequence data on the human genome is likely to be in diagnostics, with the primary therapies being prenatal diagnosis and abortion. There are a large number of important issues that have been raised with regard to genetic testing. These include worries about the quality of informed consent when dealing with complicated statistical and probabilistic information and limited access to genetic counselling worries about genetic privacy and confidentiality and genetic discrimination and concerns about a new eugenics as testing slides from cystic fibrosis to baldness, a tendency toward obesity, homosexuality, and other value-laden traits (for example, Andrews et al 1994, Kevles & Hood 1992, McGee 1997).
In addition to chromosomal aberrations, other intrinsic biomarkers for genetic or metabolic changes may be applicable as biological dosimeters, such as germ line minisatellite mutation rates or radiation induced apoptosis, metabolic changes in serum, plasma or urine (e.g., serum lipids, lipoproteins, ratio of HDL LDL cholesterol, lipoprotein lipase activity, lipid peroxides, melatonin, or antibody titers), hair follicle changes, and decrease in hair thickness, triacylglycerol-concentration in bone marrow, and glycogen concentration in liver. Whereas the first three systems mentioned are noninvasive or require only blood samples for analysis, the latter systems are invasive and therefore appropriate for radiation monitoring in animals only. Dose response relationships have been described for most of the intrinsic dosimetry systems, yet their modification by microgravity remains to be established.
Providers, insurers, and patients can all be kept in close contact with one another through the use of e-technologies. For example, if a new screening procedure for colon cancer or a new treatment for hair loss is approved by an insurer, both providers and patients can be alerted and services quickly made available for appropriate patients. Posting these announcements and alerting the respective providers and patients effectively serves as a marketing effort for the insurer.
Also from Theophrastus, hair madness. Should all else fail, a tea of Asplenium trichomanes (mixed with olive oil) was once reputed to cure baldness.(Drop a sprig or two into your husband's tea.) By all appearances it has not been successful.
Prior to contact, Yuqui women plucked their eyebrows and brow hairs from the forehead, giving them the appearance of balding men. Following contact, this practice was discontinued, although older women, who had plucked their hair for many years, usually have few eyebrow hairs and abnormally high foreheads. Men cut the hair across their foreheads into 'bangs using bamboo slivers. Today, men cut their hair short, in the Western fashion, and women may cut their hair short or braid it in the style of many Bolivian peasant women. Yuquiwomen also wore baby slings that marked their gender, something that a man would never do. If men transported children, they would do so by carrying them on their shoulders with the child clinging to their hair to keep from falling.
Side effects include erythema, desquamation, and hair loss. Late effects occur months to years after radiotherapy in approximately 5 of individuals. Serious effects include skin, bone, or cartilage necrosis telangiectasias and atrophy alopecia and local carcinogenesis. Retinoids are vitamin A analogues that inhibit cell proliferation and malignant transformation. Complete and partial responses have been documented for oral iso-tretinoin (1 mg kg day) in large, recurrent, or metastatic SCC (123). Responses, however, are maintained only while the patient is taking the medication, and tumors recur after stopping treatment. Isotretinoin is best indicated to prevent the development of new SCC's in susceptible individuals. An important limiting factor is toxi-city, both acute and chronic, and some side effects are severe enough to preclude further therapy. Frequent acute side effects include cheilitis, dry skin, hair loss, elevated liver enzyme levels, and hypertriglyceridemia. Chronic...
Active androgens and more specifically 5a-dihydrotestosterone (DHT) interact with the androgen receptor (R) in target tissues to form hormone receptor complexes which activate protein synthesis. Low (50-75 mg) or high (200-400) doses of spironolactone interfere with DHT binding with its receptor to form inactive complexes at the nuclear level. From Tremblay.
Ivermectin has been a recommended therapy option for cats with mites including Otodectes, Cheyletiella, Notoedres, Sarcoptes and Lynxacarus. A dosing regimen is 200 xg kg on three occasions over 2 weeks administered orally or subcutaneously. The propylene glycol diluent can be an irritant and some cats may resent injection and develop localised alopecia. Ivermectin seems to be a safe means of treating skin parasites, but it is not licensed in the UK for veterinary use in this species. Care should be exercised in using this product in cats less than 6 months of age. Adverse reactions to ivermectin have followed both oral and injection use and include neurological signs (Lewis et al., 1994 Paradis, 1998). Ivermectin has also been applied topically for effective control of ear mites and Cheyletiella (Page et al., 2000).
Psychogenic alopecia Psychogenic alopecia is considered to be uncommon as a single primary clinical entity (Sawyer et al., 1999). It is difficult to assess how often cats with a pruritic skin disease develop a stereotypic component to the overgrooming. In some cases the initial pruritic trigger may no longer be present, but the overgrooming has become self-perpetuating. The underlying pathogenesis of stereotypic behaviour such as incessant overgrooming, hair pulling and self-licking may include pituitary hormones such as a-melatonin-stimulating hormone (a-MSH). This is produced as part of a stress response and leads to the production of endorphins that reduce further self-grooming but have an addictive reinforcement role. The clinical presentation of psychogenic alopecia may include generalised symmetrical alopecia, particularly of the medial forearms, caudal abdomen, inguinal region and dorsal lumbar areas, and occasionally focal areas may be affected, such as the tail or a limb. In...
Erythema multiforme, interface dermatitis, exudative dermatitis with ulceration Papulocrusting dermatitis, alopecia Papulocrusting dermatitis, urticaria-angioedema, erythema multiforme Multifocal alopecia, pruritus, toxic epidermal necrolysis Multifocal alopecia, pruritus, toxic epidermal necrolysis, pemphigus foliaceus-like disease Erythema, alopecia pruritus Alopecia, atrophy Atrophy, fragility Erythema, alopecia, angioedema Alopecia erosions In another case allergic contact dermatitis was suspected to be due to carpet deodorant. The cat was presented with alopecia and crusts on the plantar surfaces of the metacarpal and metatarsal areas, and crusting and cracking of the pads. The histopathological findings included acanthosis, mild to moderate perivascular to interface dermatitis, with lymphocytes, some macrophages and eosinophils. There was mild intracellular oedema and crusting of the pad epithelium. Removal of the deodorant was associated with an improvement and there was a...
Mohair is the white, lustrous fiber produced by the Angora goat (capra hircus aegagrus). Most goat breeds have double coats (to highly variable degrees), consisting of an outer coat of coarse guard hairs and a relatively short undercoat of fine down that sheds annually. The practice from early times of selecting for white, wavy, lustrous, single-coated (i.e., no coarse guard hair) fleeces that do not shed eventually resulted in the stabilization of this type of fleece and an animal that has both high priority for and high efficiency of fiber production. Only recently have nonwhite (e.g., brown and black) Angora goats become popular with specialty breeders. In spite of mohair's specialty status and historically low production, it has been the subject of many studies and research reports. Some of these were in association with wool, and much of the research added to our understanding of human hair growth, a topic that remains economically and sociologically important.
There are some specific dilemmas while selecting appropriate AED in WWE. Weight gain and weight loss has been associated with AEDs. Other adverse effects that may limit the use of the drug in WWE are hair loss and excessive hair growth.6 Acceptance of drug-related cosmetic side effects to some extent may also depend on the socio-economic-cultural factors.7 In developing countries cost factors and easy availability of the drug need to be considered in addition to effectiveness for seizure control and cosmetic side effects.
The erythroderma is usually diffuse, although it may be confined to the extremities or trunk and may resemble sunburn. The rash may be subtle and is often missed in heavily pigmented patients or when the patient is examined in a poorly illuminated room. Erythroderma may resolve in 3 to 5 days, and a fine desquamation of the hands and feet follows in 5 to 14 days. Other dermatologic manifestations include conjunctival and mucosal hyperemia, petechiae, alopecia, and fingernail loss. The differential diagnosis is broad and includes scarlet fever Rocky Mountain spotted fever leptospirosis rubeola meningococcemia streptococcal TSS SSSS Kawasaki syndrome toxic epidermal necrolysis SJS gram-negative sepsis and exfoliative drug eruptions.
Pancreatic paraneoplastic alopecia This syndrome is also termed 'shiny cat syndrome' because of the profound shiny appearance of the skin on the ventrum. The relationship between the pancreatic (and occasional hepatic) carcinoma to the skin lesions is unknown. The clinical signs are observed in moribund to lethargic aged cats, and include bilateral symmetrical alopecia of the ventrum and limbs, dry fissured to crusting footpads and a shiny appearance to the skin in some cases, possibly due to excessive grooming. Systemic signs are profound and include anorexia, weight loss and lethargy. The diagnosis is achieved from a thorough physical examination that may reveal abdominal abnormalities confirmed with imaging, especially with ultrasound, that allows the collection of a fine-needle aspirate (or biopsy at laparotomy) to obtain tissue samples. There are no distinct changes in serum biochemistry or haematology. The histological changes in a skin biopsy are very helpful, and include...
On physical examination, the most important finding in a peripheral nerve process is reduction or absence of reflexes. The sensory examination, which includes tests of proprioception, vibratory sensation, and pain and temperature sensibility, is also often abnormal. When the motor system is involved, in addition to weakness, wasting and fasciculations may be seen. Autonomic dysfunction can cause hair loss, anhidrosis, pupillary dysfunction, orthostatic hypotension, and tachy- and bradyarrhythmias.
The skin suffers toxic effects itself, including cancer, primary irritation, allergic reactions, hair loss, pigment disturbances, ulceration, and chloracne. Dermatitis is an inflammation of the dermis. Irritant contact dermatitis and allergic dermatitis can both be caused by exposure to chemicals and produce similar symptoms, including hives, rashes, blistering, eczema, or skin thickening. The difference between them is that a true allergy takes time to develop, typically at least two weeks whereas irritation does not require a previous exposure. For example, no one reacts to poison ivy when first exposed. Only after a second or subsequent exposure does the itchy rash develop.
Symptoms of riboflavin deficiency include a reduction in growth rate, stiffness of gait, alopecia (hair loss), seborrhea (crusty exudates), vomiting, and cataracts. Other deficiency symptoms that have been observed are increased blood neutrophil granulocytes, reduced immune response, discolored kidney and liver tissue, fatty liver, and degeneration of the myelin of the sciatic and brachial nerves. Females with severe deficiency have also been
Recommended intakes of selenium for adults are based on the criterion of maximizing plasma glutathione peroxidase activity. Based on an estimated selenium content of the fetus of 1000 mg, across pregnancy this would require that an additional 4 mg day be consumed. The EAR is therefore increased from 45 to 49 mg day and the RDA from 55 to 60 mg day. The UL is determined on the basis of hair loss and brittle nails, which occur at higher levels of intake, and is the same as that set for nonpregnant women. An intake of 60 mg day is also recommended throughout pregnancy in the United Kingdom, which is the same as the prepreg-nancy value for that population.
An excellent anticonvulsant for generalized and focal seizures. Recently it has started to be used for nonconvulsive disorders, including migraine prevention and as a mood stabilizer for bipolar disorders. Valproic acid comes in Depakene and Depakote forms. Seizures controlled with this medication include myoclonic seizures, absence seizures, and mixed-type seizures. Side effects include initial transient sedation and abdominal pain (better tolerated with the Depakote form). It may also increase the appetite (causing weight gain), cause some transient hair loss (which improves with zinc supplementation), or cause liver and blood count abnormalities, although this is rare. Hyperammonemia and pancreatic dysfunction have also been reported. In children younger than 3, and especially younger than 2, valproic acid may cause a severe fatal liver disease in a frequency as high as 1 in 300. Many patients taking valproic acid may have an associated carnitine...
What are the effects of treatment for patchy alopecia areata In a report of 84 patients using normalsaline controls, 86 of patients treated with triamcinolone responded, compared with only 7 of control patients.12 Injections of triamcinolone acetonide, 0-1 ml of 5 mg ml, were given at weekly or two-weekly intervals on three occasions. The number of injections was determined by the size of the area of alopecia, with each injection producing a tuft of hair approximately 0-5 cm2. Ninety-two per cent of patients with localised disease showed regrowth at 6 weeks, compared with 61 of those with alopecia totalis. This decreased to 71 at 12 weeks for alopecia areata and 28 for patients with alopecia totalis. In an observational study comparing triamcinolone acetonide and triamcinolone hexacetonide involving 34 areas of alopecia in 11 patients, 64 of the sites injected with triamcinolone acetonide and 97 of the sites injected with triamcinolone hexacetonide regrew.13
The lowest observed effect level (LOEL) is that dose of a test agent at which the exposed animals may show some changes associated with the substance but the changes are not considered adverse effects. The no observed adverse effect level (NOAEL) is that dose at which there are no statistically or biologically significant increases in frequency or severity of effects between the exposed and the control groups. For each toxic substance, an adverse effect may be manifested by a separate threshold dose. Figure 6.4 illustrates progressively adverse responses hair loss, reduced fertility, and liver pathology. The risk assessor would judge that hair loss is not an adverse effect and assign a NOEL. The lowest observed adverse effect level (LOAEL) is the dose of the substance at which there are statistically no biologically significant differences in the frequency or severity of adverse health effects between the exposed and the control groups. The lowest observed effect (LOEL) is...
Biotin is an essential cofactor for the four carboxylase enzymes propionyl CoA carboxylase, methylcrotonyl CoA carboxylase, pyruvate CoA car-boxylase, and acetyl CoA carboxylase. It is endo-genously derived from lysine and also present in its protein-bound form in small amounts in many foods. Holocarboxylase synthetase (HCS), which forms the inactive parent apoenzyme, is also biotin dependent. Enzyme activation requires free biotin, which is released by the action of biotinidase this enzyme also plays an essential role in the recycling of biotin for further use. A deficiency of biotinidase, therefore, results in depletion of biotin and a functional defect of the carboxylases. Symptoms include hypotonia, lethargy, vomiting, and ataxia. Recurrent metabolic acidosis may occur. Alopecia and a generalized erythematous rash are common. The symptoms are more severe in HCS deficiency. The characteristic pattern of organic acids is present in both disorders. The diagnosis is made by measuring...
The eyebrow marks the lowest portion of the forehead. The eyebrows should never be clipped or shaved because their delicate contour and form are valuable landmarks for the meticulous reapproximation of the wound edges. Furthermore, it is unlikely that they will grow back in exactly the same fashion as they had been prior to the injury. If debridement in any hairy area must take place, the scalpel should cut in an angle parallel to the hair follicles to minimize the area of subsequent alopecia.
Cowden syndrome is a rare autosomal predisposition characterized by multiple hamartomas and a high risk of breast, thyroid and, perhaps, other cancers (Eng, 2000). These hamartomas can arise in tissues derived from all three embryogenic germ-cell layers. The cardinal features of this syndrome include trichilemmomas, which are hamartomas of the infundibulum of the hair follicle, and mu-cocutaneous papillomatous papules. Breast cancer develops in 20-30 of female carriers. Other tumours seen among patients with Cowden syndrome include adenomas and follicular cell carcinomas of the thyroid polyps and adenocar-cinomas of the gastrointestinal tract and ovarian cysts and carcinoma. Cowden syndrome is caused by germline mutations in the PTEN gene.
Vitiligo can be found in autoimmune families in association with Addison disease, alopecia areata, pernicious anemia, or mucocutaneous candidiasis, with an incidence 10-15 times higher than in the general population. Antibodies to thyroid, adrenal gland and gastric parital cells can be demonstrated in vitiligo patients using modern techniques, antibodies reactive with melanocytes have been consistently-found in vitiligo patients' sera. The levels of these antibodies are greatest in patients with actively progressing disease and in vitiligo patients with other autoimmune disease. Both melanocyte-specific antibodies and antibodies reactive to other cells in addition to melanocytes have been identified. Some of these antibodies are specific for proteins involved in melanization such as tyrosinase and tyrosinase-related protein 1. Antibodies to a melanocyte-specific 85 kDa antigen have been described in dogs, cats and horses with vitiligo. Similar antibodies are found in a chicken model...
Clinical manifestations of hyperthyroidism reflect increased catabolism and excessive sympathetic activity caused by excess circulating thyroid hormones. Symptomatic manifestations of hyperthyroidism include weight loss despite normal or increased appetite, heat intolerance, anxiety, irritability, fatigue, muscle weakness, palpitations, and oligomenorrhea. Signs of hyperthyroidism include goiter, tremor, hyperreflexia, fine or thinning hair, thyroid bruit, muscle wasting, and cardiac arrhythmias such as sinus tachycardia or atrial fibrillation. The presentation of hyperthyroidism varies with age. Young patients typically present with hypermetabolism, while older patients may present primarily with tachyarrhythmias or cardiac failure. Rarely, elderly patients experience only muscle wasting, apathy, confusion, or a state of depression known as apathetic hyperthyroidism. Clinical features of hypothyroidism include cold intolerance weight gain constipation edema of the hands, feet, and...
Unlike abrasions and lacerations, contusions do not always indicate a direct impact site because of tracking of blood (Fig. 9). Direction of force can be determined in abrasions and lacerations (e.g., abraded layers of skin pushed to one side, unequal undermining of a laceration consistent with tangential force 3 ). If extravasated blood collects in deep soft tissue (hematoma), bruising is not apparent initially and is appreciated only by incision of the suspected injured site (Fig. 10 refs. 3 and 8). The scalp is a site of hidden bruises (Fig. 11). Scalp hair covers contusions. A scalp contusion may not be appreciated externally until the scalp is reflected. Hemorrhage is typically seen at the scalp-skull interface, which shifts with blunt impact. If the individual survives, blood may reach the skin surface, and the consequent bruise can appear more recent. The extent of bleeding is increased if the injured tissue is loose, vascular, or both (e.g., periorbital, genital areas see Fig....
Azathioprine interferes with both B- and T-cell responses to antigenic stimulation. Generalized myelosuppression is a common side effect resulting in leukopenia and, to varying degrees, thrombocytopenia and anemia (megaloblastic) and is generally seen within the first few weeks. Other observed toxicities include hepatitis, cholestasis, hepatic vein thrombosis, pancreatitis, dermatitis, and alopecia. Prolonged use also predisposes to malignancies such as squamous cell carcinoma of the skin and lip, cervical carcinoma, and lymphoproliferative disorder.
Other cutaneous changes resulting from local radiation injury include epilation, desquamation, and necrosis. Epilation or alopecia begins within 2 to 3 weeks after doses of 3 Gy (300 rad) are received. Epilation may be complete after doses above 5 Gy (5 rad) and may be permanent after doses above 6 Gy (600 rad). Doses of 12 to 15 Gy (1200 to 1500 rad) result in dry desquamation within 2 to 3 weeks. Doses in excess of 25 Gy (2500 rad) result in wet desquamation, blistering bulla, and ulceration within 3 to 5 weeks. Radionecrosis is seen after doses above 50 Gy (5000 rad).13
Is considered to be a primary form of keratinisation defect however, there seem to be no obvious similarities apart from the same breed being affected. The mode of inheritance of the seborrhoea is suspected to be autosomal recessive. Kittens are affected within 6 weeks of age, with generalised mild to severe scaling, a greasy coat and a rancid smell. Alopecia may develop to include most of the body. The histological changes in skin biopsies include hyperplastic superficial lymphocytic perivascular dermatitis with papillomatosis and diffuse orthokeratotic hyperkeratosis affecting the skin surface and follicles. There is no effective treatment for these cats, which are most unsuitable as pets. This is not a pruritic condition.
This variant of SCC is confined to the epidermis and hair follicles. It is very similar to the human disease termed Bowen's disease. There may be an association with papilloma and FeLV viral infections. The skin lesions are seen in middle-aged and older cats, and include papules, nodules and plaques with crusting and alopecia. An important feature is that haired and pigmented areas are affected. Treatment options may include surgery, although new lesions tend to develop. Retinoids have been recommended, but are expensive, and such therapy should be carefully monitored (Guaguere et al., 1999). Hair-follicle tumours Trichoepithelioma Rare Alopecia mucinosa Areas of alopecia and scaling
Reported in children as young as 3 years of age 94 . Common lithium side effects in children include weight gain, nausea, diarrhoea, tremor, enuresis, fatigue, ataxia, leukocytosis and malaise. Less commonly seen side effects are renal, ocular, thyroid, neurological, dermatological and cardiovascular. Changes in growth, diabetes and hair loss have also been reported 95,96 . Younger children may experience more side effects than older children 97 .
Azathioprine (Immuran Wellcome) has been used as an immunosuppressive and immunomodulatory agent for the treatment of autoimmune skin diseases, polyarthritis and inflammatory bowel disease in the cat. Adverse reactions may include myelosuppression, hepatotoxicosis, vomiting, panniculitis, drug eruptions and alopecia. These reactions have limited the use of this drug in the cat. Azathioprine is a prodrug, being converted principally within the liver to the purine analogue 6-mercaptopurine (6-MP). The 6-MP is converted into cytotoxic thioguanine nucleotides, which suppress immune cell replication and response, while xanthine oxidase and thiopurine methyltrans-ferase (TPMT) catalyse the conversion of 6-MP to the inactive metabolites. The administration of azathioprine to cats at dosages of 1.1-2.2 mg kg body weight on alternate days has been associated with thrombocytopenia and leucopenia while treating pemphigus foliaceus. There are no clear indications for the use of this drug for...
Cyclophosphamide in this dosage range is usually well tolerated but a variety of side-effects may occur, including bone marrow suppression (primarily leukopenia), hemorrhagic cystitis, nausea, partial alopecia, amenorrhea and impaired spermatogenesis. The use of alkylating agents may also have long-term potential for increasing the incidence of malignancy, particularly acute leukemia. These side-effects require that the clinical indications for immunosuppressive therapy be strong and that patient exposure to the drug be limited.
In addition to the infections mentioned above, numerous other infections can occur on the face. In children, impetigo on the face is common, as is dermatophyte infections (tinea faciei and tinea barbae). Staphylococcal folliculitis is also seen on the face. The face and scalp are also a common site of involvement in secondary syphilis in which individuals develop moth-eaten alopecia, scaly or moist papules around the nose and at the angles of the mouth. Flat warts are frequently seen in males as a result of spreading the virus by shaving. Numerous molluscum contagiosum on the face of an adolescent or adult are suggestive of HIV. Patients with this disorder should be tested for HIV.
Clinical signs include non-seasonal pruritus often affecting the head and neck, including otitis externa (Plate 6.9). Miliary dermatitis, symmetrical alopecia, eosinophilic plaque and ulcerative dermatitis secondary to severe self-trauma may also be seen. Gastrointestinal signs of vomiting or diarrhoea occur occasionally.
Accelerated aging syndromes No distinct pheno-copy exists for normal aging, but there are several genetic diseases syndromes that display some features of accelerated aging, including Hutchinson-Gilford syndrome (classic early onset Progeria), Werner's syndrome, and Down's syndrome. Patients with these syndromes suffer from many signs of premature aging including hair loss, early greying, and skin atrophy, and also suffer from premature age-related diseases such as atherosclerosis, osteoporosis, and glucose intolerance. The defined genetics involved in these syndromes provide strong evidence for the genetic basis of aging.
Intertriginous infections with either Candida or Trichophyton are often seen in patients with HIV and can be diagnosed by microscopic examination of potassium hydroxide preparations of lesion scrapings. Treatment includes topical imidazole creams, such as clotrimazole, miconazole, or ketoconazole. Scabies occurs in about 20 percent of HIV-infected patients, but classic intertriginous lesions are less common. Any patient with a scaly, persistent pruritic eruption should have lesions scraped and examined histologically for scabies mites. Treatment is with permethrin 5 cream or lindane lotion. Human papillomavirus infections occur with increased frequency in immunocompromised patients. Treatment is cosmetic or symptomatic and may include cryotherapy, topical therapy, or laser therapy. Other dermatologic conditions that occur with increased frequency among HIV-infected patients include psoriasis, atopic dermatitis, and alopecia. Referral for dermatologic consultation is appropriate.
Consumer involvement has been a strong feature of the CSG from the very beginning. This is because skin disease greatly affects the quality of life of the individual and because much of the trial work in skin disease has been dominated by answering questions that are important to the pharmaceutical industry. Consumers help us to redress that imbalance. At present (Autumn 2002) the skin group has 55 groups working on topics, both common and rare, such as acne, alopecia, bullous pemphigoid, eczema, excessive sweating, psoriasis, skin cancer and vitiligo. About 30 active consumers are involved at many
Allergic skin diseases are important because they form the majority of skin diseases observed in the cat. Cats may present with a variety of manifestations of allergic skin disease, including papulocrusting (miliary) dermatitis, symmetrical alopecia and EGC. Such diseases most often are caused by allergic reactions to parasites (most notably fleas, but also mosquitoes, occasionally Otodectes ear mites and possibly trombi-culids), food allergens and inhaled allergens (atopic disease).
In addition to making antibodies, most people will also demonstrate delayed hypersensitivity to Candida antigens when subjected to skin testing with extracts of this organism. As described above, patients with defects in cell-mediated immunity are at higher risk for superficial Candida infections. This finding is especially apparent in conditions such as AIDS and in the condition known as chronic mucocutaneous candidiasis. AIDS patients are commonly afflicted with recurrent oral Candida infections. Patients with chronic mucocutaneous candidiasis have long-lasting and often disfiguring superficial candidiasis without obvious predisposing causes. Endocrinopathies, thymomas, vitiligo, alopecia, and a tendency to develop other types of infections are found in some of these patients. A variety of immunologic abnormalities have been described in this condition, but of these, defective cell-mediated immunity to Candida antigens, as manifested by negative delayed hypersensitivity skin tests...
Because it can act as a foreign body, increasing the risk of wound infection, hair should be removed as completely as possible with clipping 1 to 2 mm above the skin with scissors.12 Shaving the area with a razor damages the hair follicle, allowing bacterial invasion, and is associated with a tenfold increase in infection rates when compared with clipping. An alternative method to clipping is to use ointment or saline to clear hair away from wound edges. Hair should never be taken from the eyebrows, because of the potential failure of that hair to regenerate. Likewise, hair may provide good landmarks for alignment of wound edges during suturing, and removal at the skin-hair interface (eyebrows or scalp) should be avoided when possible.
The mammalian epidermis is comprised primarily of ker-atinocytes, a subpopulation of which are stem cells. Epidermal stem cells are multipotential they produce progeny that differentiate into interfollicular epidermis and sebocytes and contribute to all the differentiated cell types involved in forming the hair follicle, including the outer root sheath, inner root sheath, and hair shaft. It is not yet understood whether one primordial epidermal stem cell creates the stem-progenitor cell populations that maintain the interfollicular epidermis, the hair follicle, and sebaceous gland, or whether the stem cells that maintain each of these specific cell types are equivalent, with their fate determined by the local environment. However, accumulating evidence supports a model whereby the microenvironment, or niche, affects differentiation toward particular lineages. For example, cultured rat dermal papillae cells can induce hair follicle formation by rat footpad epidermis, in which follicles...
First, secreted factors elaborated by or induced by cells composing the stem cell niche can function to direct stem cell fate decisions. However, the precise signaling pathway or pathways may be different for each stem cell type and within each stem cell niche. Studies in Drosophila indicate that support cells adjacent to stem cells secrete factors required for maintaining stem cell identity and for specifying stem cell self-renewal. Both JAK-STAT signaling and TGF-b signaling have been implicated in the regulation of stem cell behavior by surrounding support cells in Drosophila. In mammals, the Wnt signal transduction pathway has been demonstrated to play a role in specifying stem cell self-renewal in HSCs, although the Wnt signal may be secreted from the stem cells themselves and may act in an autocrine loop to control stem cell proliferation. Wnt signaling may also be involved in directing the proliferation of stem cells, transit-amplifying cells, or both in the intestinal...
Body Dysmorphic Disorder (BDD) is characterized by a preoccupation with an imagined defect in one's appearance or, in the case of a slight physical anomaly, then the person's concern is markedly excessive (American Psychiatric Association, 1994). The most common preoccupations are with the nose, skin, or hair and other features on the face however, any part of the body may be involved and the preoccupation is frequently focused on several body parts simultaneously. Complaints typically involve perceived or slight flaws on the face, asymmetrical or disproportionate body features, thinning hair, acne, wrinkles, scars, vascular markings, pallor, or ruddiness of complexion.
Actinic keratoses (AK) are premalignant skin lesions occurring in sun-damaged skin. They appear clinically as erythematous papules with a rough scaly surface (18). Early lesions may be felt more than seen. Most commonly, AK affect the exposed skin of the face and upper extremities. The cheeks, forehead, and dorsum of hands are frequent locations (Fig. 8). The lower lip (actinic cheilitis) and, in balding men, the scalp are also involved. Lesions are multiple and develop gradually over the years. Most tend to become thicker (hypertrophic AK). The rate of malignant transformation for each individual AK is approximately 5 , but in patients with multiple lesions the risk is over 20 . On histopathological examination the most characteristic findings are variable degrees of focal epidermal displa-sia with overlying parakeratosis and crowding of basal cells. The dermis shows solar elastosis.
Thallium is a potent rodenticide that has largely fallen out of favour since the 1980s owing to its toxicity. The use of this agent is banned in some countries. Its mode of action involves interference with nerve transmission and mitochondrial function. Clinical signs of toxicity are either acute or chronic in nature. The acute form is characterised by vomiting, depression and marked abdominal pain, whereas chronic cases are manifested by neurological deficits and severe skin and mucosal changes, such as erythema, alopecia and ulceration. The prognosis is usually poor in such cases, with treatment being principally directed at minimising any further gastrointestinal tract absorption using Prussian blue or activated charcoal. Potassium chloride has been used to accelerate renal excretion of thallium. The use of chelating agents, such as diphenylthiocarbazone, is controversial, and generally no longer recommended.
Pubic and axillary hair is preserved, and there is an increase in light, thin hair ('peach fuzz') on the face and neck, back, arms, and thighs (lanugo hair). Patients have low body temperature and poor tolerance to cold exposure because of their malnutrition-induced lowered metabolic rate and the loss of insulation of the diminished subcutaneous tissue. Layers of clothing tend to hide their cachectic appearance. Bradycardia and hypotension are common and secondary to decreased sympathetic drive due to malnutrition.
One specific consequence of feline fear can be the onset of grooming-related behavioural problems. Most cats groom their flanks when confused, mildly upset or unable to avoid some threatening stimulus. The behaviour seems to have little effect on the layering or the quality of the coat, but is believed to have a stress-relieving function, possibly mediated by the release of opiates. Such stress-induced grooming is usually harmless, but in some cases cats will over-groom in response to continued stress (Luescher et al, 1991) and the resultant hair loss will induce many owners to seek veterinary advice. Before reaching a diagnosis of stress-related hair loss it is important to rule out all likely dermatological reasons for the over-grooming, and investigation of conditions such as flea allergic dermatitis and food hypersensitivity should always be carried out before referral. When the hair loss is located on the caudal ventral abdomen the potential for an underlying cause such as FLUTD...
There are three types of expanders a self-inflating expander that is osmotically powered and expands slowly at a constant rate (this is still experimental) (50) an expander with a distant filling valve (the most common type) and an expander with an incorporated filling valve on its surface. Directional expanders that expand more at one end than the other may be useful for correction of male-pattern baldness.
Clusively in the transitional zone of the prostate gland. The growth and development of the prostate is under the influence of testosterone, specifically its active metabolite dihydrotestosterone (DHT). After conversion by the enzyme 5-a reductase, DHT stimulates androgen receptors in the prostate, which results in the production of growth factors such as epidermal growth factor (EGF). These factors then promote the hyperplasia seen in BPH. It has been postulated that a reduction in apoptosis is also involved in the development of BPH, by causing an imbalance in the ratio of proliferation and apoptosis and hence leading to glandular hy-perplasia. The process also involves an increase in the amount of stromal and smooth muscle tissue of the transitional zone. Histologically, initially small stromal nodules are seen in the transitional zone around the urethra, followed by hyperplasia of the glandular structures. These changes are seen in prostates of men as young as 40, and are...
Clinical signs are variable and are most commonly observed in young animals. The skin lesions include scaling, which can be associated with the mites themselves, so-called walking dandruff, with mild pruritus. In cats, miliary dermatitis or symmetrical alopecia may be seen.
Moist with water or saline dressings until adequate debridement is accomplished. Each phosphorus particle must be removed. The application of copper sulfate solution blackens the phosphorus, aids in visualization, and provides neutralization. Alternatively, a Wood's lamp may be used. Some adherent toxins are extremely difficult to remove from the skin. Epoxy resins and cyanoacrylates (glues) may be removed by swabbing with acetone. Use of vegetable or mineral oil or saline-soaked gauze pads for the eyes and mucous membranes is safe. Hot tar, typically inflicting burns to the face and upper extremities, should be allowed to cool prior to removal. Effective tar removal has then been reported using Neosporin cream, Tween 80, plain Vaseline, Shur Clens, Desolv-It, or mayonnaise. No attempt should be made to remove tar by mechanical means, since this may increase tissue destruction and result in hair follicle loss.
Perhaps the most obvious extracellular structures are flagella (sing flagellum), thin hair-like structures often much longer than the cell itself, and used for locomotion in many bacteria. There may be a single flagellum, one at each end, or many, depending on the bacteria concerned (Figure 3.10). Each flagellum is a hollow but rigid cylindrical filament made of the protein flagellin, attached via a hook to a basal body, which secures it to the cell wall and plasma membrane (Figure 3.11). The basal body comprises a series of rings, and is more complex in Gram-negative than Gram-positive bacteria. Rotation of the flagellum is an energy-dependent process driven by the basal body, and the direction of rotation determines the nature of the resulting cellular movement. Clockwise rotation of a single flagellum results in a directionless 'tumbling',
Keratoacanthoma (KA) is a tumor derived from hair follicle epithelium and associated with HPV 9, 16, 19, 25, and 37. It is a rapidly growing neoplasm that resembles SCC. Whites are more commonly affected than other racial groups and the tumors present in sun-exposed areas of the extremities, head, and neck. KA affects all age groups (occurring most often in the middle-aged and elderly) and it has a 3 1 predominance in men. Sun exposure is the main predisposing factor, but immuno-suppression and exposure to tar are also important (132). The five clinical variants are described here.
Minoxidil, in tablet form, is usually reserved for the treatment of severe or refractory hypertension, and reported toxicity has been rare. A common side effect of minoxidil is hirsuitism. In 1988, a 2 topical solution of minoxidil was approved for the treatment of baldness. At least one case report exists involving ingestion of the topical solution. Regardless of the preparation, the most common symptoms of toxicity include hypotension and tachycardia. In patients with renal failure, fluid retention and pericardial effusion have been reported. Treatment is supportive and includes intravenous fluids. If the hypotension is persistent, dopamine or phenylephrine should be considered. Vasopressors with b-adrenergic activity, such as epinephrine, should be avoided because of the potential for excessive cardiac stimulation. b blockers can be used for symptomatic tachycardia.
Gastrointestinal symptoms including hemorrhage develop acutely within 12 to 48 h. A latent period with constipation is then followed in 2 to 5 days by neurologic sequelae, painful paresthesias of the lower extremities, myalgias, headache, lethargy, tremors, ataxia, delirium, coma, and seizures. Respiratory failure and dysrhythmias may cause death in severe cases. Chronic sequelae include various neurologic syndromes, neuropathies, and alopecia. Urine sediment may be of diagnostic value, showing RBCs and protein. Liver function tests may be abnormal. Thallium can be measured in the hair, serum, and urine.
However, cases of clinical disease and asymptomatic infection due to L. infantum and other species are reported, and wild cats have been incriminated as reservoirs for leishmaniasis in endemic Mediterranean countries. Cutaneous lesions alone have been reported in association with L. venezuelen-sis and unspecified Leishmania spp. in Europe, South America and the southern USA. Lesions have included diffuse areas of alopecia and granulomatous dermatitis of the head, scaling and pinnal dermatitis, and ulceration and nodules. Systemic involvement with L. infantum has been reported in association with jaundice, vomiting, hepatomegaly, splenomegaly, lymphadenomegaly, membranous glomerulonephritis and granulomatous gastroenteritis. There is a report of successful treatment of one cat with cutaneous disease using meglumine antimonate (Hervas et ah, 1999).
There are no breed, sex or age predilections. The skin lesions are usually observed around the head, especially the pinnae and planum nasale, and the claw beds, with extension to the face (bridge of the nose, muzzle, around the eyes), tail and ventral abdomen, including around the nipples. The claw beds tend to have a thick caseous green purulent discharge of multiple digits and feet (Plate 6.16). The claws are usually normal in appearance (cracked claws have been seen in feline pemphigus foliaceus, onychomadesis has been reported in pemphigus vulgaris in the cat). The skin lesions consist of pustules and vesicles, although they are transient and readily replaced by erosions and overlying crusts and alopecia. The cats may resent handling of the skin and may be pyrexic, lethargic and lame, with peripheral lymphadenopathy. One may also appreciate weight loss. The footpads may be hyperkeratotic.
Considered to be a prohormone, because it is converted in extratesticular tissues to other biologically active steroids. Testosterone may be reduced to the more potent androgen, 5a-dihydrotestosterone, in the liver in a reaction catalyzed by the enzyme 5a-reductase type I and returned to the blood. This enzyme is a component of the steroid hormone degradative pathway and also reduces 21-carbon adrenal steroids. Testosterone is also reduced to dihydrotestosterone in the cytoplasm of its target cells mainly through the catalytic activity of 5a-reductase type II, whose abundance in these cells is increased by the actions of testosterone. Dihydrotestosterone is only about 5 as abundant in blood as testosterone and is derived primarily from extratesticular metabolism. Some testosterone is also metabolized to estradiol (Fig. 7) in both androgen target and nontarget tissues. A variety of cells, including some in brain, breast, and adipose tissue, can convert testosterone and androstenedione...
Telogen effluvium is hair loss resulting from a major stressful event. This may include pregnancy and delivery, major surgery, major illness usually requiring hospitalization, or crash diets. The event causes hair to arrest in the telogen growth phase of the hair. Two to three months after the event, when new hairs are growing, the telogen hairs are shed. The patient often notices hair clogging the shower drain or numerous hairs on the pillow upon rising in the morning. The patient and the patient's family notice appreciable thinning that is sudden and often quite alarming. Diagnosis is based on diffuse hair loss in the appropriate clinical setting. A related disorder is anagen effluvium, which is secondary to systemic chemotherapeutic agents. Patients should be reassured that complete hair loss is unlikely and actually heralds new hair growth.
Hormones are known to act as promoters. For example, estrogen administered to menopausal females increases the risk of endometrial cancer. The synthetic hormone diethylstilbestrol (DES) used to be given to pregnant women with high miscarriage risk to improve their chances of carrying the pregnancy to full term. Tragically, it has been found that daughters produced by those pregnancies are at a high risk of contracting cervical cancer in their late teens or early 20s. Testosterone, or more precisely its metabolite (dihydrotestosterone), promotes prostate cancer in men.
The five major classes of touch receptors illustrated in Fig. 1 include three (Pacinian corpuscles, Merkel's disks, and Ruffini's corpuscles) that are common to both hairy and glabrous (nonhairy) skin. Hair follicle receptors are unique to hairy skin, and Meissner's corpuscles are found primarily in glabrous skin. All of these types of somato-sensory mechanoreceptors have fibers designated as type II, indicating that they have a similar diameter, a similar degree of myelination, and a similar conduction rate. Hair follicle receptor Hair follicle receptor Pacinian corpuscle Hair follicle Merkel's disk Ruffini's corpuscle
Sarah is 22 years old and has two patches of alopecia areata over the frontal and parietal scalp that have been present for 8 months (Figure 43.1). At the age of 10 she developed alopecia totalis that regrew spontaneously after 9 months. At the age of 14 she developed a solitary patch of alopecia areata that regrew after two intralesional injections of triamcinolone acetonide 6 weeks apart. She has a past history of atopy, her mother has idiopathic hypothyroidism, and a great aunt had become totally bald after receiving a telegram notifying her of her husband's death in the second world war. Sarah's only recent stress was breaking up with her boyfriend of 4 years, however, that occurred after the hair loss had begun. Figure 43.1 Patchy alopecia areata Figure 43.1 Patchy alopecia areata
We found no systematic reviews or RCTs for oral ciclosporin. In a small case series, six patients received oral ciclosporin, 6 mg kg day for 12 weeks.45 All patients had some regrowth, however cosmetically acceptable regrowth occurred in only two of five patients with alopecia totalis universalis and in the single patient with patchy alopecia areata. All patients had relapsed within 3 months of stopping therapy. A randomised study of 26 patients with alopecia totalis or universalis compared topical 10 ciclosporin daily with photochemotherapy three times a week and intravenous thymopentin, 50 mg three times a week every 3 months over 9 months.23 All patients had previously been unresponsive to sensitising therapy for at least 12 months. None of the patients in the study had any cosmetic clinical improvement by the end of the study.
Mural folliculitis is a term that denotes a new syndrome recognised in cats. The common histological theme is lymphocytic and histiocytic infiltrate of the hair follicle in the outer sheath in the isthmus and infundibular regions. The infiltrate may extend to the epidermis, including neutrophils and eosinophils, and the follicles may be ablated by a pyogranuloma-tous inflammation leading to atrophy. The main presenting clinical signs include generalised alopecia and scaling. There are five forms of this syndrome, which loosely groups different disease processes with a range of similar histological features. One form of this condition is associated with epithe-liotropic lymphoma, another with sebaceous gland atrophy and sebaceous adenitis. The latter has been described in two forms. In one report a 10-year-old cat developed extensive hair loss and skin biopsies revealed an absence of sebaceous glands and pyogranuloma-tous inflammation around the hair follicles. In two other cases there...
Selenium deficiency signs tend to overlap those seen in vitamin E deficiency. However, even with presumably adequate vitamin E intakes, very low dietary Se concentrations have been reported to result in weight loss, listlessness, alopecia, myopathy, hepatic necrosis, exudative diathesis, pancreatic fibrosis, reproductive disorders, and impaired immune function, varying with species and other aspects of diet composition. 7
Biotin supplementation has little effect on the growth performance of growing animals. Biotin supplementation of sow diets improved reproductive performance and reduced the incidence of hoof cracks and foot pad lesions. 1 A synthetic diet, or one containing desiccated egg white or specific sulfa drugs, is required to produce a biotin deficiency. Deficiency signs that have been reported include alopecia, spasticity of the hind legs,
Signs of ear disease may include head shaking and scratching. Changes to the pinnae include erythema, scaling and alopecia. There may be discomfort and resentment of palpation of the ear canal and an odif-erous discharge. The presence of abnormal ear carriage, aggression on examination, head tilt and other neurological signs are further indications of potentially severe otitis. If the pinnae are affected with pustules, crusts and exudate, one should consider scrapings for mites and impression smears. Hair plucks and scrapes should be cultured for dermatophytes, especially with focal alopecia and scaling.
Breed predisposition for cats with abnormal hair coats, such as sphinx and Devon rex breeds. Some cases have been associated with retrovirus and herpes viral infections, and underlying neoplasia including thymoma and paraneoplastic alopecia syndrome associated with hepatic and pancreatic neoplasia. Dermatophytosis has been called one of the great pretenders because there are so many potential kinds of presentation. The classic signs include alopecia and scale with central healing. One can also see just alopecia, (nasal facial) folliculitis and furunculosis, onychomycosis and granulomas. Paronychia may be the only sign in some cats. Occasionally one may see a pustular form that may appear like a bacterial pyoderma or even mimic pemphigus foliaceus or erythematosus (Plate 6.12).
Dissecting cellulitis of the scalp is an inflammatory and scarring disease of the scalp and neck. It is most commonly seen in young African-American males. Clinically, the disease begins with boggy tender nodules on the scalp and neck. The nodules suppurate and develop sinus tracts. Hair loss develops over these nodules, and with time, a permanent scarring alopecia results. The etiology is unknown. It may be seen in association with acne conglobata and hidradenitis suppurativa, where together these three diseases are referred to as the follicular occlusion triad. Treatment is difficult and often unsuccessful. Therapy includes topical and systemic antibiotics topical, intralesional, or oral corticosteroids isotretinoin and excision. Therapy is best managed by a dermatologist. Acne keloidalis is a perifollicular inflammatory process of the scalp resulting in hypertrophic and keloid scarring. The exact etiology is unknown. It is most common in African-Americans, and it is more common in...
Perhaps the most common problem with tarantulas involves the hairs on their abdomen. When threatened, these spiders can use their hind legs to flick these hairs a distance of 1 to 2 m. The body of their hair follicle is studded with what appears to be spurs when viewed with a dissecting microscope and can become imbedded in skin. The hairs are quite irritating and can lead to a significant contact dermatitis. Cases have been reported of these hairs being impaled in the cornea of a victim, necessitating surgical removal.
Pilosebaceous units contain sebaceous glands, sensory end organs, arrector pili muscle, hair, and the hair follicle. Thick hair, such as on the scalp, is terminal hair fine, nearly imperceptible hair, is vellus hair. Depending on the part of the body, the sebaceous unit may be predominant (e.g., nose). The hair follicle has three named portions (from the skin to the base) the infundibulum (to the sebaceous gland duct), the isthmus (from the duct to the arrector pili muscle insertion), and the inferior portion (below the pili muscle insertion). Hair arises from the base of the hair follicle (the hair bulb). In the hair bulb are cells that make the hair along with melanocytes incorporated into the growing hairs. The hair bulb surrounds a dermal structure called the hair papilla. This papilla regulates the hair bulb activity. The mature hair has a ringlike configuration of several distinct layers (from outer to inner) vitreous membrane, outer root sheath, Henle's layer, Huxley's layer,...
Demodicosis has been reported as an uncommon disease associated with a variety of dermatological manifestations, including ceruminous otitis externa localised alopecia, erythema, scaling, crusting and pyoderma of the head, neck and ears and generalised alopecia, erythema, variable scaling, papulocrusting dermatitis and secondary pyoderma. Clinical disease has been reported in cases associated with two species of mite. The long, slender form, Demodex cati, has been reported since the mid-nineteenth century and inhabits the hair follicle. The second species of mite has a short abdomen and may be found in the stratum corneum. Previously termed the stubby feline demodex mite, it is called Demodex gatoi (Desch 8c Stewart, 1999). Infestation with D. gatoi may resemble allergic skin disease with pruritus, and excessive grooming leading to alopecia, scaling, crusting, erythema and broken hairs. The pruritus may involve the head, neck, elbows, legs, flank and ventral abdomen. The diagnosis is...
The history of the acute illness may not alert the physician to the chronic nature of the underlying problem. The physical examination provides the clue to the diagnosis of long-standing malnutrition. Overall physical care and hygiene are frequently poor. Infants have very little subcutaneous tissue. The ribs protrude prominently through the skin, and the skin of the buttocks hangs in loose folds. There may be alopecia over a flattened occiput, reflecting that the baby has been allowed to lie on his or her back all day. Muscle tone is usually increased (although sometimes these babies are hypotonic). This increased tone is most notable in the lower extremities, and infants may manifest scissoring, similar to infants with cerebral palsy.2
SCROTAL ABSCESS The important distinction with a scrotal abscess is whether the phlegmon is localized to the scrotal wall, i.e., simple hair follicle abscess, or involves, and even perhaps originates from, infection in one of the primary intrascrotal organs, i.e., testis, epididymis, bulbous urethra. This distinction can be very difficult late in the course of the disease process when a scrotal mass may be the only discernible finding. A simple hair-follicle scrotal-wall abscess can be managed by incision and drainage. Oftentimes wound care can be simplified by circumferential excision of the entire roof of the abscess. This allows access for wound care and sitz baths and assures healing from the base outward. Antibiotics are rarely needed in an immunocompetent male.
CLINICAL FEATURES Clinically one sees areas of alopecia with broken-off hairs and scale at the periphery. The alopecia is patchy and usually nonscarring ( Fig. 238-4). Occasionally, tinea capitis is associated with an intense inflammatory response. This is manifested as a boggy, tender, indurated plaque with superficial pustules and overlying alopecia. This is referred to as a kerion, and it may result in permanent scarring and alopecia.
The primary symptom of a pantothenic acid deficiency in growing swine is an abnormal gait in the hind legs referred to as goose stepping. 9 Other deficiency symptoms include reduced growth, anorexia, diarrhea, dry skin, rough hair coat, alopecia, and reduced immune response. 1 Gestating and lactating gilts fed a low pantothenic acid diet developed fatty livers, enlarged adrenal glands, intramuscular hemorrhage, eccentric dilatation of the heart, rectal congestion, atrophic ovaries, and infantile uteri. 10
In addition to its myeloablative effects, HDC is extremely toxic to other tissues with dividing cells, such as the gastrointestinal tract, the skin, and the hair follicles. Acute toxicities include cramping and dysfunction in the gastrointestinal tract, mouth sores, nausea, diarrhea, rashes, and fatigue. Total hair loss is very common but varies with the type of chemotherapy used. Severe organ toxicity is less common but can be fatal. The lungs are particularly sensitive to some drugs (e.g., vincristine in the Solid Tumor Autologous Marrow Program I regimen), and life-threatening interstitial pneumonitis can occur, resulting in fluid accumulation and reduced blood oxygen. Other severe adverse effects may include liver damage and inflammation of the bladder. Cardiac events occur more often with HDC. For these reasons, patients who underwent HDC ABMT were usually hospitalized for several weeks and sometimes for months if complications occurred. During hospitalization, patients were at...
Hidden scalp contusions. (A) Contusion (arrow) hidden by scalp hair, which was partly cut at autopsy. (B) Another case showing reflected posterior scalp. Contusion at interface between scalp and skull. Bruising was not evident externally. Fig. 11. Hidden scalp contusions. (A) Contusion (arrow) hidden by scalp hair, which was partly cut at autopsy. (B) Another case showing reflected posterior scalp. Contusion at interface between scalp and skull. Bruising was not evident externally. 2. Epithelial regeneration (from hair follicles and wound edges)
The most prevalent adverse effect of Norplant is the unpredictability and irregularity of menstrual cycles, especially in the first year of use. Cycles may be shorter or longer than usual and associated with more or less bleeding there may be bleeding between cycles, or no bleeding at all. Although there is no cure for irregular bleeding patterns, short-term palliation of the problem can be achieved by the use of low-dose oral estrogen therapy (e.g., ethinyl estradiol 20 mcg orally per day for two to three weeks). Other side effects include mild weight gain, headaches, hair loss, and new onset or exacerbation of depression.
Forty patients relapsed during the study period no average length of remission before relapse was given. Patients who relapsed were treated again with the pulse regimen. Infections, amenorrhoea, weight gain or loss and alopecia were common side-effects. There was one report of haemorrhagic cystitis. Kaur and Kanwar21 used an almost identical regimen of pulse dexamethasone plus cyclophosphamide to treat 50 patients with pemphigus over a course of 2 years. At the time of publication, almost half the patients had improved to some degree, but were still receiving monthly pulse treatments (range 2-15 months of treatment). Another five patients had responded well and were receiving only oral cyclophosphamide 50 mg day. Six patients did not respond and 13 patients were lost to follow up, all of whom had reportedly improved on pulse treatment. Thus no patients achieved complete remission. Three patients (6 ) died of septicaemia. Other side-effects reported included cardiac...
|How To Stop Hair Loss And Regrow It The Natural Way||www.totalhairregrowth.com|
100 Hair Growth Tips
100 Hair Growth Tips EVERY Balding Person Should Know. This Report