[Acute aseptic arthritis in major sickle cell syndromes]

We report 9 cases of febrile aseptic arthritis which occurred in 6 adults presenting with major sickle cell disease. The monoarticular arthritis affected the knee in 8 cases and the ankle in 1 case. Body temperature ranged from 38 degrees C to 39.5 degrees C in 7 cases, and neutrophilia (12.7 to 24 x 10(9)/l) was noted on six occasions. The always sterile synovial fluid contained 100 to 1700 cells/mm3 in 6 cases and 5200 to 12,500 cell/mm3 in 3 cases. Uricacidaemia was normal, and a search for crystals in the synovial fluid gave negative results. Bone scintigraphy and magnetic resonance imaging, performed in 3 patients, revealed the presence of a juxta-articular cortical bone infarct, whereas standard radiography was normal. In all patients, a brief immobilization and treatment with non-steroidal anti-inflammatory drugs resulted in complete cure in less than 10 days. These cases illustrate the characteristics of sickle cell arthritis, a rare complication of major sickle cell disease. Clinically, the condition resembles septic arthritis, being febrile and showing granulocytosis, but articular needle aspiration corrects the diagnosis. The mechanisms underlying these disorders have not yet been elucidated, but the bone scintigraphy and MRI performed in our patients are in favour of a reaction to a juxta-articular bone infarct.