Periprosthetic Joint Infection by Streptococcus bovis Reveals Hidden Colorectal Cancer: A Case Report

Periprosthetic joint infection (PJI) caused by <i>Streptococcus bovis</i> (<i>S. bovis</i>) is rare but clinically significant due to its established association with colorectal neoplasia. Early recognition and interdisciplinary management are essential to ensure favorable outcomes. We report the case of a 68-year-old woman who presented with a chronic fistula and signs of active infection 20 years after uncemented total hip arthroplasty. Cultures from the wound identified <i>S. bovis</i>, prompting further evaluation. Imaging and laboratory tests supported a diagnosis of chronic PJI. A two-stage revision was performed, beginning with implant removal, debridement, and placement of a vancomycin/gentamicin-loaded spacer. Given the pathogen's known link to gastrointestinal malignancy, the patient underwent colonoscopy, which revealed a tubulovillous adenoma with carcinoma in situ. Surgical resection was performed with curative intent. Six months later, the patient underwent successful reimplantation. At three-month follow-up, clinical and radiographic assessments showed favorable recovery. This case reinforces the importance of gastrointestinal screening in patients with <i>S. bovis</i> PJI, as early detection of associated colorectal lesions may impact treatment strategies and prognosis.