Osteonecrosis in Behcet's disease seen on bone scintigraphy

A 35-year-old man with Behcet's disease who satisfied the criteria of the International Behcet's Disease Study Group was admitted to the rheumatology outpatient clinic with polyarthralgia of the knees, ankles, elbows, and wrists. The knees were also swollen. Fie had been taking cyclosporineA and corticosteroid therapy to treat uveitis. Nonsteroidal anti-inflammatory drugs were added to his treatment regimen. Despite this therapy, his knee symptoms persisted. Bone scintigraphy with Tc-99m MDP was performed to evaluate the joints and skeletal system. The whole-body images showed increased tracer uptake in the joints of the left shoulder, right elbow, right wrist, left ankle, and in both knees. In addition, an irregular patchy increased accumulation was seen in both tibias and in the distal parts of both femurs. Scintigraphic findings suggested osteonecrosis in related regions rather than synovitis. Magnetic resonance imaging confirmed the osteonecrosis, showing multifocal infarction sites in the distal femurs and proximal tibias. Osteonecrosis was explained in this patient by either vasculitis as the basic origin of Behcet's disease or corticosteroid treatment. In the literature, osteonecrosis in Behcet's disease is rarely reported. This potentially debilitating disorder should be considered in Behcet's disease, especially when corticosteroid treatment will be started; in such cases, scintigraphic evaluation might provide an early diagnosis.