Comparative clinical and incremental cost-effectiveness analysis of treatments for pelvic inflammatory disease in southern Brazil

Objective

This paper evaluates the accuracy of C-reactive protein (CRP), leukocyte count, and neutrophil-to-lymphocyte ratio (NLR) for diagnosing tubo-ovarian abscess (TOA) and assessing the cost-effectiveness of different treatment regimens for pelvic inflammatory disease (PID), with and without TOA.

Method

A retrospective cohort study was conducted between January 1, 2003, and December 30, 2021, including women aged 13–80 years diagnosed with PID. The analysis focused on the incremental cost-effectiveness ratio of different treatment regimens.

Results

C-reactive protein, leukocyte count, and NLR were found to be statistically significant markers for diagnosing TOA. Out of 907 PID cases, 705 achieved clinical cure with initial treatment. The most cost-effective treatment for mild PID without TOA was ceftriaxone combined with azithromycin, which was considered less costly and more effective in the cost-effectiveness analysis. For severe PID with TOA, ampicillin combined with gentamicin and clindamycin was more cost-effective compared to ampicillin with sulbactam plus doxycycline, given a willingness-to-pay threshold of US$213.57 for a 4.2% increase in cure rate.

Conclusion

The study's findings support the use of CRP, leukocyte count, and NLR as diagnostic tools for TOA. Ceftriaxone combined with azithromycin is recommended as the first-line treatment for mild PID at our institution due to its cost-effectiveness. For TOA, ampicillin combined with gentamicin and clindamycin is a cost-effective option if the healthcare system's willingness to pay exceeds US$213.57 for a 4.2% increase in cure rate, contributing valuable insights for PID treatment strategies from a hospital's perspective. The average time of hospital admission for TOA was 3 days. After discharge, patients received oral doxycycline until completing 14 days of treatment.