Studies in Diseases of Muscle

In the previous reports of this series1the metabolism of creatine and creatinine in patients with progressive muscular dystrophy, myasthenia gravis and muscular wasting subsequent to disease of the nervous system was discussed. In the present study the factors influencing the metabolism of creatine and creatinine in myotonia congenita, myotonia atrophica, amyotonia congenita and dystonia musculorum deformans were investigated. In addition, the effect of muscular activity (tremor) on the output of creatine and creatinine was determined. MATERIAL AND METHODS The subjects included 2 patients with myotonia congenita, 4 with myotonia atrophica, 1 with amyotonia congenita, 2 with dystonia musculorum deformans and 1 with paralysis agitans. The methods employed in this investigation were similar to those described in a previous report.1aThe patients were maintained on a diet free from creatine and creatinine. The urine was collected carefully in twenty-four hour samples, and the urinary creatine and creatinine were