A Rare Case of Periprosthetic Joint Infection with Streptococcus dysgalactiae subspecies dysgalactiae.

Periprosthetic joint infection (PJI) is a rare but most vital complication after joint arthroplasty and requires a revision surgery. Synovial fluid analysis is essential in diagnosis of the PJI, and conventional and molecular microbiologic investigations may help in determining the cause of the infection. With this unusual case, we aimed to present the second instance in the literature of PJI of the knee caused by Streptococcus dysgalactiae subspecies dysgalactiae (SDSD). S. dysgalactiae PJI in the literature are commonly Streptococcus dysgalactiae subspecies equisimilis (SDSE), and SDSD mostly infects animals. A farmer with comorbid illnesses who works with cattle and sheep experienced periprosthetic knee joint infection caused by SDSD. Surgical excisional debridement with open washing, decompression, and liner exchange were performed. The identification of the bacteria was done with VITEK MS as SDSD. After 1-year follow-up, the patient has fully recovered without recurrence.