After bone marrow aspiration procedure; some complications like pain and bleeding at the puncture site may be expected but some serious complications like osteomyelitis and soft tissue infections may also rarely occur. In this case we present a boy with recurrent fever. During etiologic investigation, familial Mediterranean fever (FMF) gene M694V mutation was +/+. Patient was treated with oral colchicine however fever persisted. The patient was considered as colchicine resistant FMF and steroid treatment was planned. Bone marrow aspiration procedure was executed to rule out malignancy. Three months after bone marrow aspiration, he was readmitted with complaint of left pelvic pain, difficulty in walking without support and standing on his left foot. Radiological imaging demonstrated left iliopsoas abscess and left sacroiliac osteomyelitis. Patient was successfully treated with intravenous ampicillin-sulbactam and clindamycin treatment for 6 weeks. Then oral amoxicillin-clavulanic acid treatment was continued for 2 weeks. Patient was discharged without any surgical procedure. On 1-year follow-up he could walk without any support.

Keywords: bone marrow aspiration, children, iliopsoas abscess, sacroiliac osteomyelitis