Mycotic Aneurysms in Intestinal Transplantation: A Case Series

INTRODUCTION: Mycotic aneurysms (MA) are a potentially fatal complication following intestinal transplantation (ITx). Their occurrence arises from several factors, such as chronic abdominal sepsis, potential for contamination of the vascular grafts during enteric anastomoses and the heightened burden of immunosuppression. METHODS: A retrospective review of a prospectively maintained database of all adult ITx from December 2007 to June 2025 was conducted. RESULTS: Among 168 ITx, six patients (3.6%) experienced eight MA episodes. MA occurred bimodally, early post-transplant (2-8 weeks) or in a later phase (55-377 weeks). Recurrence occurred in two patients, averaging 132.4 weeks after initial diagnosis. A history of hollow viscus perforation or anastomotic leak was present in 83.4%. Diagnosis was peri-operative in two cases due to rupture, while others were detected electively via angio-CT. Recurrences were subtler, identified incidentally or with mild symptoms. Apart from targeted antibiotic and antifungal treatment, management strategy pivoted around endovascular stent grafting (ESG) followed by an aneurysmectomy and creation of a new conduit. Post-operative mortality at first presentation occurred in 66.6% of patients, with 50% within a week. Two patients survived recurrence, with one remaining alive 6.5 years post-diagnosis. CONCLUSION: MA in ITx is rare but commonly fatal, often linked to bowel perforation or anastomotic complications. Diagnosis relies on angio-CT or intraoperative identification at the time of emergency laparotomy. Management involves ESG and conduit resection. Early aggressive control of potential contamination sources after ITx is crucial, though general conclusions are limited by low incidence.