Rhabdomyolysisをきたした急性型アルコール性ミオパチーの2症例

Two Cases of Acute Alcoholic Myopathy Associated with Rhabdomyolysis

　Rhabdomyolysisをきたした急性型アルコール性ミオパチーの2症例を報告した。症例1は62歳男性。約40年の飲酒歴があり，下痢が続いた後から精神症状が出現。入院時，下肢近位筋の筋力低下がみられたが筋肉の腫脹や把握痛はなかった。低カリウム血症を伴いCKとミオグロビンが著明な高値を示した。急性期と回復期に施行した虚血下運動負荷試験では乳酸の上昇がみられず，筋肉解糖系の抑制が示唆された。症例2は43歳男性。約27年の飲酒歴があり，急性の両下肢脱力のため入院。両大腿に把握痛を認め，四肢近位筋で筋力低下がみられた。血中カリウムは正常範囲内でCKとミオグロビンが著明な高値を示した。急性型アルコール性ミオパチーの発生機序については不明な点が多いが，エタノールによる筋肉解糖系の抑制が重要な役割を果たしている可能性が指摘されており，症例1でもこれを示唆する所見がみられた。

We reported two cases of acute alcoholic myo-pathy associated with rhabdomyolysis. The first case was 62 year-old man, who had been drinking every day for 40 years. Following diarrhea, he had psychic symptoms, and was admitted to our hospi-tal. He was in a state of delirium. Tremor in extremi-ties, dytharthria and weakness of lower extremities were observed. Neither swelling nor grasping pain were seen in any muscles. Laboratory data showed severe hypokalemia and high levels of serum muscle enzymes and myoglobin. An increase of lactate and pyruvate was not seen in ischemic exercise test performed at the acute or the recovery phase. It was suggested that glycolysis in muscles was suppressed in this case.

The second case was 43 year-old man, who had been drinking every day for 27 years. Rapidly pro-gressive weakness of both lower extremities was seen, and he was admitted to our hospital. Grasping pain of both legs and proxymal muscle weakness of extremities were observed. Laboratory date showed normokalemia and high levels of serum muscle enzymes and myoglobin. Muscle biopsy showed no abnormal findings in histology and electron microsc-copy.

Although the pathogenesis of acute alcoholic myopathy is unknown, suppression of muscle glycolysis enzyme caused by ethanol may play an important role in the first case.