Ruptured hepatic artery aneurysm precipitated by gangrenous perforated appendicitis: a case report

Hepatic artery aneurysms are among the most common visceral artery aneurysms although still relatively rare. Repair of aneurysms >2 cm in diameter is important due to the high rate of rupture and associated mortality. Here, we present a case of a sudden rupture of a hepatic artery aneurysm after presentation with a perforated gangrenous appendicitis. There is increasing evidence that expansion and rupture of abdominal aortic aneurysm is related to degradation of elastin and collagen by matrix metalloproteinases (MMPs). Elastin degradation leads to expansion, while collagen degradation leads to rupture. The activity of MMPs has been shown to be upregulated by both sepsis and peritonitis. Here, we suggest that the inflammation from sepsis and peritonitis led to the activation and/or upregulation of MMPs, which precipitated aneurysm rupture via collagenase activity.