Effect of HIV infection on atypical squamous cells of undetermined significance.

Detection of atypical squamous cells of undetermined significance (ASCUS) is a cervical cytologic finding that is suggestive but not definitive of squamous intraepithelial lesions (SILs). We examined the risk, characteristics, and progression of ASCUS in women with and without human immunodeficiency virus (HIV) infection. Cervical Papanicolou (Pap) test and colposcopy data were obtained at the first 10 semiannual visits for the HIV Epidemiology Research study of 774 HIV-infected and 480 demographically similar, HIV-uninfected women in the United States. Multiple logistic regression models and Cox proportional hazards models were utilized. ASCUS was more common among HIV-infected women (odds ratio [OR], 1.6 [95% confidence interval {CI}, 1.3-2.0] to 2.6 [95% CI, 1.9-3.6]) after adjustment for human papillomavirus (HPV) infection and other risk factors (e.g., race, condyloma, and prior Pap test result). Among women with normal Pap test results at enrollment, the cumulative incidence of ASCUS was 78% among HIV-infected women and 38% among HIV-uninfected women. HIV-infected and HIV-uninfected women with ASCUS did not differ by prevalence of indices of inflammation (inflammation on Pap test and leukocytes on cervical gram stain). HPV infection, including high risk types, was more common among HIV-infected women with ASCUS. Among women with ASCUS, 60% of HIV-infected and 25% of HIV-uninfected women developed SILs (P < .01). Compared with HIV-infected women with higher CD4+ lymphocyte counts, HIV-infected women with CD4+ lymphocyte counts < 200 cells/microL were more likely to present subsequently with a SIL detected by Pap test (OR, 1.7; 95% CI, 0.8-3.6). Higher risk of SIL following the appearance of ASCUS among HIV-infected women, especially women with low CD4+ lymphocyte counts, supports the need for follow up with colposcopy and histologic examination, as indicated, to allow early detection and treatment of SIL.