USE OF LIGASE CHAIN-REACTION WITH URINE VERSUS CERVICAL CULTURE FOR DETECTION OF CHLAMYDIA-TRACHOMATIS IN AN ASYMPTOMATIC MILITARY POPULATION OF PREGNANT AND NONPREGNANT FEMALES ATTENDING PAPANICOLAOU SMEAR CLINICS

Ligase chain reaction (LCR) (Abbott Laboratories, Abbott Park, Ill.) w ith first-catch urine specimens was used to detect Chlamydia trachomat is infections in 465 asymptomatic military women attending clinics for routine Papanicolaou smear tests. Results were compared to results of cervical culture to determine the sensitivity of the urine LCR and th e possible presence of inhibitors of amplification in pregnant and non pregnant women. Discrepant results for LCR and culture were resolved b y direct fluorescent antibody staining of culture sediments, two diffe rent PCR assays, and LCR for the outer membrane protein 1 gene. The pr evalence of Chlamydia in specimens by urine LCR was 7.3% compared to 5 % by culture. For 434 women with matching specimens, there were 11 mor e specimens positive by LCR than were positive by culture, of which al l but one were determined to be true positives. There were four cultur e-positive, LCR-negative specimens, all from nonpregnant women. The se nsitivity, specificity, and positive and negative predictive values of urine LCR after discrepant results were resolved were 88.6, 99.7, 96. 9, and 99.0%, respectively. The sensitivity of culture was 71.4%. From the 148 pregnant women (prevalence by LCR, 6.8%), there were no patie nts who were cervical culture positive and urine LCR-negative to indic ate the presence in pregnant women of inhibitors of LCR. Additionally, a subset of 55 of the LCR-negative frozen urine specimens from pregna nt women that had been previously processed in LCR buffer were inocula ted with 5 cell culture inclusion forming units of C. trachomatis each and retested by LCR; all tested positive, indicating the absence of i nhibitors of LCR in urine from these pregnant women. The use of LCR te sting of urine specimens from asymptomatic women, whether pregnant or not, offers a sensitive and easy method to detect C. trachomatis infec tion in women.