Mycotic Abdominal Aortic and Iliac Aneurysm Caused by Streptococcus equi Subspecies zooepidemicus Bacteremia

Abstract

This report describes a case of a taxidermist who presented with sepsis and excruciating back pain a few weeks after contact with a deceased horse. Streptococcus equi subspecies zooepidemicus (SESZ) was isolated from patient’s blood and two isolated mycotic aneurysms were found. The first was located in the distal abdominal aorta and the second in the right common iliac artery. Treatment consisted of penicillin administration for 6 weeks and surgical debridement of the infected tissue combined with autologous vein reconstruction. The patient was infection-free without complaints 1 year after discharge and the venous reconstruction was patent. Reports in literature of bacteremia with SESZ leading to the development of mycotic aneurysms are very scarce and show that prognosis is generally unfavorable.

Infected Aortic Aneurysm Caused by <i>Streptococcus zooepidemicus</i>: A Case Report and Literature Review

“…This yielded 162 papers, among which were reports of 11 cases of infected AA caused by S. zooepidemicus , with information on underlying diseases, operations, and outcomes, as presented in the Table 1 . 2 – 8 )…”

“… 1 ) It is mainly transmitted through close contact with animals and consumption of unpasteurized dairy products. 2 ) The possible effects of S. zooepidemicus infection in humans include nephritis, arthritis, meningitis, pneumonia, infected aortic aneurysm, infective endocarditis, and sepsis. 1 ) When an infected aortic aneurysm (AA) is caused by S. zooepidemicus , a poor prognosis is expected.…”

Infrarenal aortic reconstruction using autologous femoral vein for a mycotic aneurysm caused by Streptococcus equi

“…Generally caused by species with a high affinity for the arterial wall, S. equi (SE) mycotic aneurysms are particularly rare [ 3 ]. A zoonotic pathogen with three subspecies— SE equi , SE ruminatorum and SE zooepidemicus —SE zooepidemicus has been most reported to cause human infections, presenting as bacteremia, meningitis, endocarditis and aortitis [ 4 , 6 ]. A ß-hemolytic Lancefield group C streptococcal bacterium, S. equi , commonly causes infections in horses, pigs, cats and goats.…”

“…Infected aneurysms are uncommon, usually caused by bacterial endocarditis, bacteremia and trauma. Staphylococcus aureus , Salmonella species, Tuberculosis, mycobacterium, Streptococcus pneumoniae and fungi are all causative organisms [ 1 , 3 , 4 ]. S. equi is a rare cause of mycotic aneurysms with a recent review identifying 12 cases in the literature [ 5 ].…”