Bilateral Wrist Septic Arthritis Caused by Group B β-Hemolytic Streptococcus: A Case Report

Septic arthritis is typically a monoarticular infection most commonly caused by Staphylococcus aureus; however, polyarticular presentations are uncommon and associated with higher morbidity and mortality. Group B β-hemolytic Streptococcus is a less frequent pathogen but may occur in patients with significant comorbidities or recent obstetric events. Early recognition is critical, as delayed diagnosis may result in joint destruction and systemic complications. We report a case of a 40-year-old woman with a history of autoimmune hepatitis status post liver transplantation on chronic immunosuppression, rheumatoid arthritis, and recent miscarriage with retained products of conception, who presented with bilateral wrist pain and swelling, worse on the left. Initial evaluation suggested an inflammatory arthritis flare due to polyarticular involvement. However, laboratory studies revealed leukocytosis and elevated inflammatory markers. Arthrocentesis of the left wrist was performed, and cultures grew group B β-hemolytic Streptococcus. The patient subsequently underwent bilateral dorsal wrist arthrotomies with synovectomy, irrigation, and debridement, yielding purulent fluid from both joints. Blood cultures confirmed bacteremia with the same organism. She was treated with intravenous ceftriaxone for a planned four-week course, with clinical improvement. Evaluation for endocarditis was negative. This case highlights a rare presentation of polyarticular septic arthritis involving bilateral wrists caused by group B β-hemolytic Streptococcus in an immunocompromised patient following miscarriage. Clinicians should maintain a high index of suspicion for septic arthritis in patients with multiple risk factors, even when presentation mimics inflammatory arthritis, as prompt diagnosis and intervention are essential to improving outcomes.