Biochemical characterization of a virus isolate, recovered from a patient with herpes keratitis, that was clinically resistant to acyclovir.
Clin Infect Dis
; 33(12): 2034-9, 2001 Dec 15.
Article
en En
| MEDLINE
| ID: mdl-11712095
ABSTRACT
In vitro susceptibility assays of herpes simplex virus (HSV) do not necessarily correlate with treatment outcome. An HSV type 1 (HSV-1) isolate, N4, recovered from a patient who presented with herpes keratitis with localized immunosuppression, was characterized for susceptibility. Although the 50% inhibitory concentration (IC(50)) for this isolate was less than the accepted breakpoint for defining resistance to acyclovir (>2.0 microg/mL), the following lines of evidence suggest that the isolate was acyclovir resistant (1) the clinical history confirmed that the infection was nonresponsive to acyclovir; (2) the in vitro susceptibility was similar to that of a thymidine kinase (TK)-negative, acyclovir-resistant virus SLU360; (3) the IC(50) of acyclovir was more than 10 times the IC(50) for an acyclovir-susceptible control strain; (4) plaque-purified clonal isolates were resistant to acyclovir (IC(50)s, >2.0 microg/mL); and (5) biochemical studies indicated that the HSV-1 N4 TK was partially impaired for acyclovir phosphorylation. Although residue changes were found in both the viral tk and pol coding regions of HSV-1 N4, characterization of a recombinant virus expressing the HSV-1 N4 polymerase suggested that the TK and Pol together conferred the acyclovir-resistance phenotype.
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Banco de datos:
MEDLINE
Asunto principal:
Antivirales
/
Aciclovir
/
Herpesvirus Humano 1
/
Herpes Simple
/
Queratitis
Límite:
Aged
/
Humans
/
Male
Idioma:
En
Año:
2001
Tipo del documento:
Article