DIAGNOSIS OF CHLAMYDIA-TRACHOMATIS INFECTIONS IN MEN AND WOMEN BY TESTING FIRST-VOID URINE BY LIGASE CHAIN-REACTION

From April to September 1993, 305 men and 447 women in Hamilton, Canad a, consented to the collection of a urethral or cervical swab, respect ively, for culture and 20 ml of first-void urine (FVU) for testing by the enzyme immunoassay Chlamydiazyme and by ligase chain reaction (LCR ) in the form of a kit from Abbott Laboratories called LCx Chlamydia t rachomatis. Evaluation of test performance with each specimen was calc ulated on the basis of an expanded ''gold standard'' of a patient foun d to be positive by culture or by a confirmed nonculture test. By usin g this expanded standard, the prevalence of infection was determined t o be 6% (27/447) for the women and 18.4% (56/305) for the men. LCR tes ting of FVU in both studies was the most sensitive approach (96%). The performance of Chlamydiazyme was as follows: cervical swab, 78.3% sen sitivity; female FVU, 37% sensitivity; and male FVU, 67.9% sensitivity . Culture was the least sensitive approach to diagnosis: female cervix , 55.6%; and male urethra, 37.5%. LCR testing of FVU from men or women diagnosed the greatest number of genitourinary tract infections with no false positives.