Miyajima H, Sakamoto M, Takahashi Y, Mizoguchi K, Nishimura Y
Rinsho Shinkeigaku. 1989 Jan;29(1):93-7.
A case of 16-year-old female with myalgia and myoglobinuria following prolonged exercise was reported. Neurological examination revealed mild weakness of proximal muscle in the lower extremities. Serum CK, LDH, myoglobin were significantly increased during the attacks. On biopsy, the muscle fibers contained myriad lipid-filled vacuoles, in predominantly type 1 fibers. Electron microscope examinations revealed numerous lipid droplets adjacent to mitochondria and glycogen particles. Carnitine level in the patient's muscle was markedly reduced (under 5% of control), but the serum carnitine concentration was normal. The muscle carnitine palmityl transferase level was not depressed. A forearm ischemic test resulted in normal lactate production. On exercise tolerance test by a bicycle ergometer, mild exercise (15-30 watts for 15 minutes) induced myalgia and marked elevation in serum CK, lactate and pyruvate, while severe exercise showed no increase in serum CK level. The findings suggest that the energy production system in the skeletal muscle was impaired. However, the enzyme activities of NADH oxidation in mitochondria and the anaerobic glycolysis pathway were within normal limits. During fasting (36 hours), there was a normal production of ketone bodies, suggesting that hepatic metabolism of lipids was normal. She showed good response to L-carnitine therapy.
报告了一例16岁女性在长时间运动后出现肌痛和肌红蛋白尿的病例。神经系统检查显示下肢近端肌肉轻度无力。发作期间血清肌酸激酶（CK）、乳酸脱氢酶（LDH）、肌红蛋白显著升高。活检时，肌纤维含有大量充满脂质的空泡，主要在1型纤维中。电子显微镜检查显示线粒体和糖原颗粒附近有大量脂滴。患者肌肉中的肉碱水平显著降低（低于对照组的5%），但血清肉碱浓度正常。肌肉肉碱棕榈酰转移酶水平未降低。前臂缺血试验导致乳酸生成正常。通过自行车测力计进行运动耐力测试时，轻度运动（15 - 30瓦，持续15分钟）诱发肌痛，血清CK、乳酸和丙酮酸显著升高，而剧烈运动时血清CK水平无升高。这些发现表明骨骼肌中的能量产生系统受损。然而，线粒体中NADH氧化和无氧糖酵解途径的酶活性在正常范围内。禁食（36小时）期间，酮体生成正常，表明肝脏脂质代谢正常。她对左旋肉碱治疗反应良好。
