Case report of multiple mesenteric mycotic aneurysms after perforated appendicitis

Mycotic aneurysms are a severe and sometimes life-threatening complication of infections or sepsis. However, mycotic aneurysms of mesenteric arteries caused by a purulent peritonitis following perforated appendicitis are very rare and not previously reported. This case report contributes to the awareness and treatment of this rare complication.

We present a case of a middle aged patient with a purulent peritonitis after perforated appendicitis. Postoperatively, recovery was not as expected. One week after laparoscopic appendectomy, CRP increased and haemoglobin levels dropped. Abdominal CT imaging revealed several mesenteric mycotic aneurysms. Because of aneurysmatic rupture, coiling of several mesenteric arteries was performed, despite the risk of bowel ischemia. After long-term antibacterial and antifungal treatment, the patient recovered completely.

Formation of mycotic aneurysms in mesenteric arteries is very rare and optimal treatment options are debatable. Given the high mortality of conservative therapy with antibiotics alone, treatment of mycotic aneurysms by surgery or endovascular treatment is strongly advised. In our case, it was decided to treat the aneurysms by endovascular coil embolization and to observe whether bowel ischemia would occur, because aneurysms were present in multiple mesenteric arteries.

Mycotic aneurysms of several mesenteric arteries should be considered as a rare but potential complication of perforated appendicitis with purulent peritonitis. In case of rupture, successful treatment can be achieved by embolization followed by long-term antibiotics. A multidisciplinary approach including surgery, interventional radiology and microbiology is highly recommended and transfer to a tertiary referral centre should be considered.