Case Presentation: A 34 year-old woman presented with 5 days of progressively worsening, throbbing left groin pain that radiated down her left thigh and was severe enough to limit ambulation. She denied injury to the area, fevers, chills, a history of arthritis or other autoimmune conditions, and intravenous drug use. Her past medical history was significant for a spontaneous abortion 12 days prior. On presentation, she was afebrile and vital signs were stable. Examination revealed tenderness to palpation in her left lower quadrant, along her left groin fold, and down her left lateral thigh. Severe pain limited passive and active range of motion of her left hip. There was no erythema, warmth, overlying skin changes, deformities, effusions, or crepitus of the left hip or groin. A pelvic exam could not be performed due to pain. Labs revealed a white blood cell count of 18.9, erythrocyte sedimentation rate of 80, c-reactive protein of 16, and creatine phosphokinase of 25. HIV screening and blood cultures were negative. CT scan of abdomen and pelvis revealed a small corpus luteum cyst in the left ovary. Transvaginal ultrasound revealed no intrauterine pregnancy and a thin endometrial stripe. Orthopedics was consulted and initially had low suspicion for septic arthritis based on clinical exam and CT findings. After no clinical improvement, an MRI of the left hip was obtained which revealed synovitis with a small effusion and possible adjacent myositis. The patient underwent an ultrasound guided fine needle aspiration of the left hip which yielded approximately 4 mL of cloudy, yellow fluid. Synovial fluid assay revealed a white blood cell count of 1045 with 76% neutrophils/bands. Gram stain revealed numerous white blood cells and gram-positive cocci in pairs, consistent with septic arthritis. The patient underwent incision and drainage of the left hip which revealed gross purulence on capsulotomy. Cultures of the synovial fluid grew beta-hemolytic Group C Streptococcus. The patient’s clinical condition improved, and she was discharged to complete a 4-week course of IV ceftriaxone.
Discussion: Septic arthritis has been reported as a rare complication post-partum or after gynecologic procedures. To our knowledge, there has also been one reported case of Group B Streptococcus causing septic arthritis of a hip after a spontaneous abortion. Staphylococcus aureus is the most common cause of non-gonoccal septic arthritis, with beta-hemolytic Streptococci as the second most common cause. Among beta-hemolytic Streptococci cases, group A Streptococcus (GAS) is the most common subtype. Group C Streptococcus (GCS) is a much more rare cause of Streptococcus septic arthritis, and it has been suggested to cause more aggressive cases of septic arthritis than GAS. Among reported causes of GCS septic arthritis, the majority are polyarticular and are associated with underlying conditions, both rheumatologic and non rheumatologic such as diabetes, injection drug use, malignancy, osteoarthritis. Regardless of the bacterial pathogen, septic arthritis is associated with significant morbidity and mortality. Permanent joint damage is seen in up to 50% of patients and mortality ranges from 7-16%.
Conclusions: This case demonstrates the importance of recognizing potential complications of a transient bacteremia, such as septic arthritis, after a spontaneous abortion. It remains imperative that clinicians have a high suspicion for septic arthritis as early detection and treatment can improve functional outcomes.