骨病変にて発症した急性リンパ性白血病の1例

Acute Lymphoblastic Leukemia with Bone Lesion : Case Report

　抄録：骨髄炎との鑑別診断が困難であった，骨病変にて発症した急性リンパ性白血病の1例を経験した．症例は12歳，女性で転倒後に左膝の疼痛，腫脹，発熱を生じた．X線像では左大腿骨，けい腓骨に著明な骨萎縮および大腿骨顆部に骨膜反応を示した．膝関節内血腫があり透視下に大腿骨遠位骨端線部での動揺性を認めた．MRIでは大腿骨，けい腓骨骨髄内全域に及ぶ広範囲な病変を認めた．初診2日後に急激な汎血球減少を来し，骨髄穿刺にて急性リンパ性白血病と診断された．画像上，骨髄炎と白血病の骨病変との鑑別は困難であり，血液疾患を疑った場合は骨髄穿刺を早期に行うことが重要と思われた．

　We report a case of acute lymphoblastic leukemia with the bone lesion, whose diagnosis differentiated from osteomyelitis was difficult. A 12-year-old girl had the pain of her left knee and the fever elevation. The radiographs showed the severe osteopenia of her left femur and tibia, and the periosteal reaction of the distal metaphyseal area of the femur. MRI showed the abnormal signal intensity in all the bone marrow of the femur and the tibia. Pancytopenia occurred 2 days after the admission, and the diagnosis of acute lymphoblastic leukemia was made by the bone marrow aspiration. The differential diagnosis of leukemia from osteomyelitis was difficult without the bone marrow aspiration.