title: A retrospective, case-control study of acyclovir resistance in herpes simplex virus.
abstract: BACKGROUND
  Occasional cases of acyclovir resistance have been documented in the treatment of herpes simplex virus (HSV) infection. Thirty-eight subjects with acyclovir-resistant infections were identified in an epidemiological surveillance program involving 1811 HSV-infected subjects in France.
  
  
  METHODS
  Twenty-three index cases from whom acyclovir-resistant HSV strains had been isolated were compared with 46 control subjects matched for immunological status. Sociodemographic characteristics, features of the acyclovir-resistant HSV episode, history of HSV infection, treatment, outcome, and immunological history were recorded.
  
  
  RESULTS
  Twenty-two index case patients presented with immunodepression. Sixty-five percent reported clinically manifest recurrences, compared with 33% of matched control subjects. Significantly more index case patients had used antiviral drugs, and they had used them more often than had control subjects. However, 26.1% of index case patients reported no antiviral exposure in the previous 2 years. Two-thirds of the strains recovered from the index case patients were isolated because of suspicion of clinical resistance to acyclovir.
  
  
  CONCLUSIONS
  Clinical treatment resistance is associated with acyclovir-resistant HSV strains, but acyclovir-resistant strains were also isolated from treatment-naive subjects.
authors: Hôpital Saint André, Bordeaux, France.
authors: Denis
authors: D
authors: Malvy
authors: Michèle
authors: M
authors: Treilhaud
authors: Stéphane
authors: S
authors: Bouée
authors: Anne
authors: A
authors: Crochard
authors: Denis
authors: D
authors: Vallée
authors: Abdelkader
authors: A
authors: El Hasnaoui
authors: Michele
authors: M
authors: Aymard
mesh_terms: D000212:Acyclovir / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000494:pharmacology*; D016022:Case-Control Studies; D024882:Drug Resistance, Viral; D005260:Female; D006561:Herpes Simplex / Q000188:drug therapy / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018139:Simplexvirus / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D000212:Acyclovir