Predictors for Invasive Therapy in the Management of Crohn’s Disease-related Spontaneous Intra-abdominal Abscess: Prognosis and Long-term Follow-up

Abstract Background Decision-making in the management of Crohn’s disease (CD)-related spontaneous intra-abdominal abscess (IAA) is challenging. This study aims to reveal predictive factors for percutaneous drainage and/or surgery in the treatment of CD-related spontaneous IAA through long-term follow-up. Methods Data were collected, including clinical manifestations, radiography and treatment strategies, in Chinese patients with CD-related IAA in a tertiary medical center from Jan 2014 to Dec 2017. A Cox proportional hazards regression model was used to identify predictors for invasive therapy, which were incorporated together to develop a prognostic nomogram. Validation of the nomogram was assessed by a separate cohort of patients with CD-related IAA from Jan 2018 to Mar 2021. Results Altogether, 33 CD patients were identified as having IAA through enhanced CT scans. The median follow-up time was 52.0 (33.5, 60.0) months. Eighteen (54.5%) patients underwent conservative medical treatment, and 15 (45.5%) patients underwent percutaneous drainage and/or surgical intervention (invasive treatment group). The 1-, 2-, and 5-year overall survival rates without invasive treatment were 69.7%, 57.3%, and 53.7%, respectively. On univariate Cox analysis, nonperienteric abscess (HR: 6.391, 95% CI: 1.970-20.728, p = 0.002), max abscess diameter (HR: 1.015, 95% CI: 1.005–1.025, p = 0.003) and width of sinus (HR: 1.246, 95% CI: 1.037–1.498, p = 0.019) were significantly associated with worse OS without invasive treatment. Nonperienteric abscess was significantly associated with worse OS without invasive treatment on multivariate Cox analysis (HR: 5.738, 95% CI: 1.763–18.672, p = 0.004). These factors were incorporated together to develop a prognostic nomogram and were externally confirmed in the validation cohort. The concordance index was 0.842 (95% CI: 0.681–0.983, p < 0.001). Conclusions Nonperienteric abscesses indicate a more aggressive treatment strategy, such as percutaneous drainage and/or surgery, in the management of CD-related IAA. A nomogram could help recognize patients who are more likely to require invasive treatment.