An Unusual Case of Streptococcus pyogenes Causing Ruptured Aortic Mycotic Aneurysm

Abstract

A 70-year-old male with a complex past medical history presents with confusion and slurred speech for 24 hours. His exam was unremarkable, and his CT head was negative. Both his C-reactive protein and white blood cell count were elevated. As part of the delirium workup, blood cultures were done which grew Streptococcus pyogenes with no obvious source. He was treated with appropriate antibiotics. To determine the source, a white blood cell scan was done, which showed increased localization within a left-sided upper mediastinum mass. Subsequently, chest CT scan with contrast showed an acute type B aortic dissection with mycotic aneurysm. Consequently, he was taken urgently for surgical management. He completed 6 weeks of penicillin G and was discharged to a rehabilitation center. This case illustrates both a rare entity, mycotic aneurysm secondary to Streptococcus pyogenes, and the importance of getting an Infectious Diseases consult in the setting of an unknown source of bacteremia.

Infected abdominal aorta aneurysm secondary to streptococcal toxic shock syndrome due to Streptococcus pyogenes: a case report from Japan

“…Infected aortic aneurysms (IAAs), although uncommon, are also associated with severe complications and mortality 2 . Although S. pyogenes is not a major causative pathogen of IAAs, 3 13 cases of S. pyogenes‐ related IAAs have been reported 4–16 . Herein, we report the case of a patient with an asymptomatic infected abdominal aortic aneurysm who successfully underwent aortic replacement with a bifurcated vascular prosthesis following S. pyogenes ‐induced STSS.…”

“…2 Although S. pyogenes is not a major causative pathogen of IAAs, 3 13 cases of S. pyogenes-related IAAs have been reported. [4][5][6][7][8][9][10][11][12][13][14][15][16] Herein, we report the case of a patient with an asymptomatic infected abdominal aortic aneurysm who successfully underwent aortic replacement with a bifurcated vascular prosthesis following S. pyogenes-induced STSS.…”

Common Iliac Artery Mycotic Pseudoaneurysm Associated with a Prevertebral Infection: A Case Report

“…2 These infections can occur in any artery, and case reports describe several locations. [3][4][5] These aneurysms and pseudoaneurysms are commonly attributed to septic emboli from infective endocarditis or direct injury (iatrogenic and traumatic) to the vessel wall. 4 Infected aneurysms are relatively rare and comprise less than 2% of all aortic aneurysms.…”

“…4 Infected aneurysms are relatively rare and comprise less than 2% of all aortic aneurysms. 3 Additionally, isolated iliac artery aneurysm/pseudoaneurysms are exceedingly rare with an incidence of 0.03%. 6 Patient presentations for pseudoaneurysms vary widely as the symptoms depend on size and location of the defect.…”

“…7 In the modern antibiotic era, the most common organisms are Salmonella and Staphylococcus aureus; however, a wide range of Gram-positive and Gram-negative organisms has been associated with these infections. 3,7 To date, no case of Proteus mirabilis causing an iliac artery pseudoaneurysm associated with direct spread from a prevertebral abscess has been reported.…”