Measurement of serum CA-125 concentrations does not improve the value of Chlamydia trachomatis antibody in predicting tubal pathology at laparoscopy

Chlamydia antibody testing (CAT) has been used to predict tubal pathology a ssociated with Chlamydia infection, the leading cause of pelvic inflammator y disease (PID). Tubal pathology not related to C. trachomatis is unlikely to be identified by CAT alone. A correlation between serum CA-125 concentra tions and the severity of adnexal inflammation during acute PID was demonst rated. The objectives of this study were to determine the prevalence of C. trachomatis infection in an Asian infertile population and to assess the ro le of a combination of serum CA-125 and CAT in the prediction of tubal path ology as shown by laparoscopy. A total of 110 consecutive women attending a n infertility clinic for work-up were recruited. Blood was taken for CAT an d CA-125 on the day of hospital admission and an endocervical swab was take n for culture of C. trachomatis prior to laparoscopy. Two (1.8%) women had C. trachomatis found in the endocervix and 28 (25.5%) women had CAT of grea ter than or equal to1:32. Serum CA-125 concentrations were >35 IU/ml in 11 (10%) women. The discriminative capacity of CAT in the diagnosis of tubal p athology including both proximal and distal obstruction was not improved by measuring serum CA-125, regardless of the threshold values of serum CA-125 concentration.