[Septic sacroiliitis: early diagnosis due to specific physical examination].

BACKGROUND: Septic sacroiliitis is an uncommon disease which represents approximately 1-4% of all joint infections, therefore it is difficult to make the right diagnosis and to start early treatment.

CASE REPORT: A 18 year old woman was admitted to the emergency room with a fever and pain in the left gluteal region. The patient was considered healthy and had no risk factors for septic arthritis. Edema and a small abscess was found in and around the left sacroiliac joint on pelvic MRI. The patient had positive blood cultures with Staphylococcus Aureus. Antibiotic treatment was initiated and lasted 7 weeks. She recovered completely and had no remaining complaints.

CONCLUSION: Physical exam and clinical suspicion are important to consider the diagnosis of septic sacroiliitis. In addition a MRI of the pelvic is the best radiographic exam to conform the diagnosis.