The value of cervical cytology in HIV-infected women.

The purpose of this study was to assess the ability of cytology to predict the results of colposcopically directed cervical biopsies in HIV-infected women. We performed a case-control study of 52 HIV(+), 31% of whom had AIDS, and 57 HIV(-) women referred to two tertiary care centers for colposcopy from July 1991 to November 1993. All 57 HIV(-) controls and 27 HIV (+) cases underwent colposcopy for evaluation of an abnormal Pap smear. The remaining HIV(+) cases (n = 25) had colposcopy as part of their routine assessment. In women with abnormal Pap smears, colposcopic biopsy agreed with the Pap smear results in 83% of 24 HIV(+) women and 65% of 37 controls (chi 2; P = 0.34). For patients with low-grade SIL on Pap smear, 14% of HIV(+) and 11% of HIV(-) women had moderate or severe dysplasia on biopsy (P = 0.52). The positive predictive value of an abnormal Pap smear was 96% in HIV(+) women vs 78% in noninfected patients (P = 0.05). In the overall series of 52 HIV(+) women, the Pap smear did not match the biopsy in 44% of patients and was less severe than the cervical biopsy results in 91% of these mismatches. The Pap smear had a sensitivity of 57%, a specificity of 92%, a positive predictive value of 96%, and a negative predictive value of 39%, when compared to biopsy results in HIV-seropositive patients. Pap smears missed 43% of biopsy-proven intraepithelial lesions in this series of HIV (+) women. However, when abnormal, the Pap smear was no worse in predicting the presence and degree of an intraepithelial lesion in HIV(+) women than in noninfected women. These characteristics may justify immediate treatment of HIV(+) women at the time of colposcopy after an abnormal Pap smear given its high positive predictive value.