MYOTONIA DYSTROPHICA: REPORT OF SIX CASES IN ONE FAMILY, WITH AN ANALYSIS OF THE METABOLIC DEFECTS

Abstract

A family pedigree in which 6 members had myotonia dystrophica is reported. An effort was made to determine if an endocrine abnormality was in any way responsible for the muscular disorders in this disease. Metabolic studies revealed an extrathyroidal hypometabolism, a slightly diminished excretion of urinary 17-ketosteroids, and normal urinary 17-hydroxvcorticosteroid and FSH levels. Seminiferous tubular atrophy with absence of spermatogenic and Sertoli cells and normal appearing Leydig cells were demonstrated by testicular biopsy. The adrenals, thyroid, and testes were stimulated with adrenocorticotrophin, thyroid stimulating hormone, and chorionic gonadotropin respectively, and responded in a normal manner. Cortisone and testosterone therapy failed to improve the muscular status. It is concluded that there is no evidence to suggest that an endocrine dysfunction is responsible for, or that substitution of a target hormone will correct the muscular component of this disease.