sorivudine and Acquired-Immunodeficiency-Syndrome

To characterize further a chronic epithelial keratitis caused by varicella-zoster virus infection in patients with acquired immunodeficiency syndrome (AIDS).. Patients with AIDS and chronic epithelial keratitis associated with varicella-zoster virus from 3 institutions were identified. Patient records were reviewed retrospectively for the following data: medical and demographic characteristics, techniques of diagnosis, physical findings, course, response to treatment, and outcome.. Sixteen patients were studied. CD4+ T-lymphocyte cell counts were available in 11 patients, with a median of 0.034 x 10(9)/L (range, 0-0.094 x 10(9)/L). Two patients had no history of a zosteriform rash. In the remaining patients, the interval between rash and keratitis ranged from 0 days to 6 years. In all cases, the keratitis was chronic and characterized by gray, elevated, dendriform epithelial lesions that stained variably with fluorescein and rose bengal. The peripheral and midperipheral cornea was most commonly affected, and, in 13 of the 16 patients, the lesions crossed the limbus. Pain was a prominent feature, occurring in 12 of 16 patients. In 9 of 12 patients tested, varicella-zoster virus was identified by culture, direct fluorescent antibody testing, polymerase chain reaction testing, or a combination of these studies, with direct fluorescent antibody testing (6 of 8 positive results) and polymerase chain reaction testing (3 of 3 positive results) appearing to be the most sensitive. Response to antiviral medication was variable.. In patients with AIDS, varicella-zoster virus may cause a chronic infection of the corneal epithelium. The keratitis is characterized by dendriform lesions, prolonged course, and frequently by extreme pain. It can occur without an associated dermatitis.

Topics: Acquired Immunodeficiency Syndrome; Acyclovir; Adult; Aged; Antiviral Agents; Arabinofuranosyluracil; CD4 Lymphocyte Count; Chronic Disease; Epithelium, Corneal; Herpes Zoster Ophthalmicus; Herpesvirus 3, Human; Humans; Keratitis, Dendritic; Male; Middle Aged; Retrospective Studies

Patients with AIDS often experience recurrent infections with varicella-zoster virus (VZV) requiring repeated or prolonged treatment with acyclovir (ACV), which may lead to the development of ACV resistance. The ACV resistance of isolates recovered from such patients is associated with diminished VZV thymidine kinase (TK) function. We determined the nucleotide sequences of the TK genes of 12 ACV-resistant VZV strains purified from nine patients with AIDS. Five VZV strains contained nucleotide deletions in their TK genes, introducing a premature termination codon which is expected to result in the production of a truncated protein. No detectable full-length TK protein could be immunoprecipitated from extracts of cells infected with these virus strains. These TK-deficient strains were cross resistant to the TK-dependent antiviral agents ACV, 9-(4-hydroxy-3-hydroxymethylbutyl-yl)guanine (penciclovir), and 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl) uracil (BVaraU). The remaining seven strains each contained a nucleotide change that resulted in an amino acid substitution in the TK protein. These substitutions occurred throughout the TK protein, namely, in the ATP-binding site, the nucleoside-binding site, between the two binding sites, and at the carboxy terminus of the protein. We determined the effects of these mutations on the stability of TK protein expression in virus-infected cells and on the sensitivity of mutants to the TK-dependent antiviral agents ACV, BVaraU, and penciclovir.

Topics: Acquired Immunodeficiency Syndrome; Acyclovir; AIDS-Related Opportunistic Infections; Amino Acid Sequence; Antiviral Agents; Arabinofuranosyluracil; Base Sequence; Drug Resistance, Microbial; Genes, Viral; Genetic Variation; Guanine; Herpesviridae Infections; Herpesvirus 3, Human; Humans; Molecular Sequence Data; Mutagenesis; Precipitin Tests; Sequence Analysis; Sequence Homology, Amino Acid; Thymidine Kinase; Viral Plaque Assay