Abiotrophia Causing Prosthetic Joint Septic Arthritis

A 71-year-old Caucasian male with a past medical history of Charcot-Marie-Tooth disease type 2 presented to our rural hospital for left knee pain, swelling, and difficulty walking. The patient had prior bilateral total knee replacements with a subsequent left knee revision due to infection. Joint aspiration was culture-positive and 16S recombinant DNA (rDNA) sequence positive for Abiotrophia defectiva. The patient underwent a left total knee extraction with a temporary antibiotic spacer insertion. On discharge, the patient received an initial six weeks of ceftriaxone 2g IV. At the outpatient six-week follow-up, the patient was cleared of the Abiotrophia infection. However, later complications and a subsequent Enterobacter cloacae infection arose.