title: Acquired resistance to acyclovir: laboratory phenomenon or clinical problem?
abstract: In tissue culture, herpes simplex readily acquires resistance to nucleoside analogue inhibitors such as acyclovir. The two possible sites where resistance may develop are in the thymidine kinase (TK) and in the DNA polymerase genes; the commonest in vitro mutant is TK negative (TK-), although some strains may induce low levels of enzyme activity. The characteristics and modes of selection of these mutants are discussed, together with a preliminary consideration of the possible situation in man when antiviral drugs come to be more widely used.
mesh_terms: D000212:Acyclovir / Q000494:pharmacology* / Q000627:therapeutic use; D004352:Drug Resistance, Microbial; D009154:Mutation; D018139:Simplexvirus / Q000201:enzymology; D013937:Thymidine Kinase / Q000235:genetics; D014777:Virus Diseases / Q000188:drug therapy*
chemical_list: D013937:Thymidine Kinase; D000212:Acyclovir