The first way to manage ACV-resistant HSV infection is, when possible, to decrease immunosuppressive treat-ments. An increase of antiviral dose should also be considered.
Several alternative antiviral drugs are also available. Penciclovir is a nucleoside analogue of guanosine and is very similar to ACV. Indeed, most ACV-resistant HSV isolates are also resistant to penciclovir. Foscarnet, a pyrophosphate analogue, and cidofovir, a nucleotide analogue of cytidine, act directly on viral DNA polymerase without previous activation by viral TK and both these molecules are active on viruses resistant to ACV because of a mutation in the TK gene.[17,18] Acyclovir-resistant management strategies usually recommend the use of foscarnet as a first line treatment and cidofovir in case of failure of foscarnet. However, in clinical practice, both of these drugs may be associated with a significant level of toxicity.
Cross-resistance between ACV and foscarnet has been documented in immunocompromised patients.[19-21] Nevertheless, foscarnet-resistant strains sensitive to ACV have also been reported. Acyclovir-resistant strains, cross resistant or not to foscarnet, have always been shown to be sensitive to cidofovir.[9,22] In addition, resistance to cidofovir, never reported so far in clinical strains, has only been described in strains selected in
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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.