Comparison of acute and subclinical pelvic inflammatory disease

The objective of this study was to compare the demographic, clinical, and microbiologic findings in women with subclinical pelvic inflammatory disease (PID) and women with acute PID.

A cross-sectional study was performed using cohorts from 2 separate studies of 1293 women at risk for PID. Most participants were recruited from emergency departments, sexually transmitted disease clinics, and family planning clinics in metropolitan centers. We compared demographic, clinical, and microbiologic findings among women with acute PID, women with subclinical PID, and women without endometritis (controls). Statistical analyses included chi-square for categorical variables, calculation of odds ratio and 95% confidence intervals, and polychotomous logistic regression when appropriate.

Similar proportions of women with acute and subclinical PID tested positive for cervical Chlamydia trachomatis (odds ratio [OR], 1.1; 95% confidence interval, 0.6-2.0) and had bacterial vaginosis (OR, 0.7; 95% CI, 0.2-1.8). The rate of cervical Neisseria gonorrhoeae infection in women with subclinical PID was intermediate between the rates in women with acute PID and controls (21% vs. 49% vs. 7%, respectively, P <0.001, test for trend). Endometrial recovery of N. gonorrhoeae and C. trachomatis in women with subclinical PID was also seen at intermediate levels. Similar distributions of teenagers, women who smoked or used illicit drugs, and women engaging in sexual intercourse during menses were found in each group. Proportions of women with subclinical PID who were black and with lower education levels were intermediate between the proportions of these characteristics in women with acute PID and controls.

Demographic and microbiologic characteristics of women with subclinical and acute PID are comparable. These findings suggest that the pathophysiological mechanisms of acute and subclinical PID are similar.