Evaluating the risk factors for developing resistance to parenteral therapy for tubo‐ovarian abscess: A case–control study

Aim The aim of this study was to identify factors that can predict the resistance to parenteral therapy in patients with tubo-ovarian abscesses (TOA). Material and Methods We conducted a case–control study involving 55 admitted patients with TOA. The subjects eligible for this study included 28 patients who failed antibiotic therapy and required surgery (surgical cases) and 27 patients who were conservatively cured (control cases). The clinical characteristics of the patients on admission were reviewed. Logistic regression analysis was performed after univariate analysis to identify potentially important variables and to calculate odds ratios with 95% confidence intervals. Results As per the univariate analysis, compared to the control cases, the surgical cases were older (40.4 vs 31.5 years), had higher white blood cell counts (14000 vs 11828 cells/mm3), higher C-reactive protein levels (16.1 vs 7.6 mg/dL), and a larger abscess diameter (6.6 vs 3.9 cm). There were no significant differences in gravidity, parity, body temperature, rate of endometrial cyst formation, and Chlamydia trachomatis infection rates between the groups. Multiple logistic regression analysis indicated that the only statistically significant risk factor predicting parenteral antibiotic therapy failure was the abscess diameter >5 cm (odds ratio = 69.6; 95% confidence interval = 9.3–527, P < 0.0001). Conclusion An abscess diameter >5 cm is an important factor for predicting the failure of antibiotic therapy in patients with TOA. Moreover, it is useful for determining whether patients with TOA should be surgically treated.