The diagnosis of human brucellosis is conventionally performed using serological and bacteriological tests. The Rose Bengal test, the serum agglutination test, and the complement fixation test are the most accepted serolog-ical tests used worldwide. These tests are based on a reaction between Brucella cell antigen and antibodies produced in response to the infection. The accuracy of the Rose Bengal test is over 99%, but it can give false positive results with sera from patients infected with Yersinia enterocolitica or other cross-reactive organisms. In contrast, the bacteriological diagnosis is based on the recovery of bacteria from the patient's blood. The biphasic method which uses both solid and liquid media in the same container has been recommended and is widely used. Using this method, it may take from 3 to 35 days to determine whether the hemoculture being tested is positive. The variation of bacterial growth in blood culture is due to a number of factors including the culture medium, the number of circulating bacteria, the time of blood collection, the volume of blood used for culture, the host's immune response system, and the intracellular characteristics of the bacteria.
Molecular-based assays using PCR have been developed that can be used in detecting various nomen species of Brucella.[20-23] Compared to standard identification methods, PCR-based assays are fast, less expensive, highly accurate, and safe to perform. For instance, with real-time PCR specific for B. abortus, B. melitensis, and B. suis, the assay can be accomplished in less than 30 min. This assay utilizes an upstream primer that is derived from the 3' end of the genetic element IS711, whereas the downstream primers and probes are designed from signature sequences specific to a species or biovar. In addition to PCR-based assays, Western blot analysis of cytoplasmic proteins has the potential to differentiate past from subclinical infection. Despite their advantages, molecular diagnostic tests have not been approved for clinical use by FDA.
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The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.