Can the Need for Invasive Intervention in Tubo-ovarian Abscess Be Predicted? The Implication of C-reactive Protein Measurements.

STUDY OBJECTIVE: To evaluate the clinical parameters of hospitalized patients with pelvic inflammatory disease (PID) for the presence of tubo-ovarian abscess (TOA) and predict the need for intervention.

DESIGN: A prospective cohort study.

SETTING: A tertiary care university medical center.

PATIENTS: Ninety-four patients were diagnosed with complicated PID and hospitalized between 2015 and 2017.

INTERVENTIONS: Patients with PID were treated with parenteral antibiotics according to Centers for Disease Control guidelines. Demographic, clinical, sonographic, and laboratory data for patients with PID were analyzed. Inflammatory markers including C-reactive protein (CRP), white blood cells (WBCs), erythrocyte sedimentation rate (ESR), and clinical parameters were collected at admission and during hospitalization.

MEASUREMENTS AND MAIN RESULTS: Forty-eight of 94 patients (51.1%) hospitalized with complicated PID were diagnosed with TOA sonographically. CRP levels were the strongest predictor of TOA, followed by WBC count, ESR, and fever on admission. The areas under the receiver operating characteristic (ROC) curve for CRP, WBC, ESR, and fever were .92, .75, .73 and .62, respectively. CRP specificity was 93.4% and sensitivity was 85.4% for predicting TOA, with cutoff value of 49.3 mg/L. Twelve patients (25%) failed conservative management and underwent surgical intervention including laparoscopy (n = 7), computed tomography (CT)-guided drainage (n = 4), and laparotomy (n = 1). In this group, CRP levels significantly increased from admission to day 1 and day 2 during hospitalization (128.26, 173.75, and 214.66 mg/L, respectively; p < .05 for both). In the conservative management group, CRP levels showed a plateau from admission to day 1 and then a decrease until day 3 (110, 120.49, 97.52, and 78.45 mg/L, respectively).

CONCLUSION: CRP is a sensitive, specific inflammatory marker for predicting TOA in patients with complicated PID, and levels >49.3 mg/L suggest the presence of TOA. In the TOA group, CRP level trends correlated well with success or failure of conservative management. Increasing CRP levels during treatment may be used as an indicator of the need for invasive intervention, and daily CRP measurements can help predict the need for invasive intervention.