Parastomal hernia after ileal conduit: Incidence, natural history and risk factors

Introduction: Parastomal hernias are a challenging complication of digestive ostomies. Ileal-conduit parastomal hernias after cystectomy have specific aspects. The aim of this study was to describe the incidence and natural history of ileal-conduit parastomal hernias in order to guide their management, as well as to identify risk factors to prevent them.

Patients and methods: All consecutive patients undergoing cystectomy with a Bricker's ileal conduit in 3 academic centers were retrospectively identified. Data were collected regarding their medical history prior to cystectomy, the operation, the postoperative period, imaging results within 5 years of follow-up, and the onset and timing of clinically or radiologically diagnosed ICPH.

Results: Among 577 patients included in the study, 115 (20.6%) developed an ICPH during the study period. Most patients did not present any symptom and the diagnosis was made at imaging in 74.8% of them. Most hernias were detected between 1 and 2 years after the cystectomy, with a mean time to diagnosis of 12.4 months. At multivariate analysis, overweight and obesity were independent risk factors for developing an ICPH (adjusted hazard ratio [aHR] 1.96; p = 0.046), while a trans-rectus position of the ostomy was a significant protective factor (aHR 0.45; p = 0.011).

Conclusions: A PH develops in almost 20% of patients after ileal conduit urinary diversion, with a mean time of onset of 12.4 months. It is often a subclinical condition detected at medical imaging. Obesity increases the risk, while passing the ileal-conduit through the rectus muscle can help to prevent it.