A case of SLE with bilateral osteonecrosis of femoral heads and bone infarct in distal of femur.

Osteonecrosis of bone is a major cause of morbidity in lupus patients, and is most common in the femoral head. It has been reported in wide range of patients (2-30%). In different studies presence of arthritis, Raynaud phenomenon, vasculitis, pleuritis, antiphospholipid and other factors were associated with this occurrence. Bone infarcts were also associated with these factors. We report a 21-year-old patient who was diagnosed as SLE about 3 years ago. When the patient was stable with hydroxychloroquine and prednisolone referred to rheumatologic clinic for mechanical knee pain, in evaluation she had bone infarct in distal femur. Two months later she came back with bilateral hip pain, and in evaluation she had bilateral osteonecrosis of femoral heads. There are many reports of femoral head osteonecrosis in lupus patients, and also one report of multiple bone infarct and pain in SLE, but we did not find any report of these two phenomena together in a patient whose disease was controlled and she took minimum of steroid and DMARD in the about 2-month follow-up, and this was very interesting for us.