Aerococcus urinae Spondylodiscitis: A Case Report and Review of the Literature.

Abstract

Background: Aerococcus urinae, a rare human pathogen, mainly causes urinary tract infection, endocarditis, and bacteremia. However, it is rarely the cause of other types of infection such as spondylodiscitis. Invasive A. urinae infection chiefly occurs in older men with underlying urinary tract disorders. The real incidence may be underestimated, as Aerococci grow in a CO2-containing atmosphere, and urine cultures are usually not incubated in this environment. There have been eight case reports of spondylodiscitis due to A. urinae. Material and Methods: We report a 9^th case occurring in an 80-year-old Caucasian man with lower back pain. The patient had predisposing conditions (diabetes and a history of urological surgery). Spinal MRI showed signs of spondylodiscitis. Two computed tomography-guided biopsies targeting the intervertebral disc and psoas muscle were not diagnostic. One of 10 blood culture bottles grew A. urinae. Results: After worsening of an L2 fracture, and unsuccessful percutaneous sampling procedures, the patient underwent surgical stabilization of T12 to L4 with multiple biopsies. Biopsy cultures grew Aerococcus urinae. Amoxicillin was administered intravenously for 14 days, followed by oral levofloxacin for 3 months. Conclusion: A. urinae should be considered in spondylodiscitis with negative cultures, particularly in older men with diabetes and urological conditions.