Prosthetic stent graft infection caused by Aerococcus urinae: A case report and literature review

Aerococcus urinae, a gram-positive, catalase-negative coccus, has emerged as a notable pathogen in clinical microbiology. It is traditionally associated with urinary tract infections in elderly males with underlying urologic conditions. Recently, A. urinae has been implicated in severe invasive infections outside the genitourinary tract including infective endocarditis, vertebral osteomyelitis, peritonitis, lymphadenitis, and discitis. We present the case of 84-year-old male with a history of aortic graft replacement who presented with five days of fever and fatigue. Blood and urine cultures grew gram-positive cocci, identified as A. urinae. Thoracoabdominal contrast-enhanced CT revealed a slightly increased soft tissue shadowing around the prosthetic stent in the ascending aorta, indicating a possible aortic stent-graft infection. Gallium-67 scintigraphy demonstrated inflammation around the prosthetic stent in the ascending aorta consistent with an aortic stent-graft infection. The patient and family opted for conservative treatment and despite a six-week inpatient course of ampicillin, followed by oral amoxicillin, the patient died one week after discharge. This is the first published case of A. urinae causing an aortic stent-graft infection. Clinicians should remain cognizant of the disseminated source of infection in cases of A. urinae bacteremia.