Got Milk? A Case of Salmonella Mycotic Aortic Aneurysm Caused by Consumption of Unpasteurized Milk

Abstract

We present a case of a 77-year-old Amish man who developed a contained, ruptured mycotic thoracic aortic aneurysm caused by salmonella bacteremia likely from consumption of unpasteurized milk. He was successfully treated with an aortic arch replacement and long-term antibiotics. CASE PRESENTATION:Our patient is a previously healthy 77-year-old Amish man who originally presented to Emergency Department (ED) with acute onset severe chest pain, intermittent rigors and myalgias. His initial work up was not suggestive of an acute bacterial process. There was high suspicion for acute coronary syndrome (ACS) due to his age and location of his pain, but ECG and cardiac enzymes did not show evidence of ischemia. Cardiology was consulted in the ED, who recommended that he stay overnight to undergo a stress test. The following day after a negative dobutamine stress echo, he developed encephalopathy, ataxia, and urinary incontinence, and was admitted to the hospital for further evaluation. He was found to have significant drop in hemoglobin and thus underwent CT imaging to evaluate for internal source of bleeding. Imaging revealed a contained, ruptured thoracic aortic aneurysm. It was also discovered that his admission blood cultures grew enterobacter species, which raised suspicion for mycotic aneurysm. Cardiac and Vascular surgery teams presented a harrowing clinical predicament: high risk of aortic rupture with delayed repair but also high risk of mortality with endovascular repair with bacteremia. The blood culture species was subsequently identified as Salmonella, making the consensus opinion of a mycotic aortic arch very likely. After shared decision making the plan was made to proceed with aortic arch replacement as endovascular options were felt to be suboptimal both in terms of anatomy and cure rate. The surgery team successfully debrided the infected aortic arch tissue and placed a Dacron graft. The patient had a relatively short and uneventful postoperative course. He was maintaining his saturations on room air and ambulating without difficulty by post-operative day two, and ultimately discharged home seven days after surgery.DISCUSSION: Infectious aortitis can present itself as localized thickening of the aortic wall to more serious complications such as aortic aneurysms with impending risk of rupture. If untreated, the complications are lethal. While salmonella infection and aortitis is a common association, the presentation is quite rare. In our patient, consumption of unpasteurized milk led to salmonella infection which ultimately resulted in bacterial seeding of a prior intimal injury or atherosclerotic plaque.CONCLUSIONS: Clinicians should maintain a high degree of suspicion of aortic aneurysm in patients with persistent chest pain despite negative ACS work-up. If mycotic aneurysm is suspected, therapy involves both antibiotics and surgery.