Autopsy study on the weight of the heart, liver, kidney and brain in Duchenne muscular dystrophy.

The weight of the major internal organs in 188 autopsy cases of Duchenne muscular dystrophy were studied in relation to the clinical course of disease and age of the patients at death. The hearts were classified into three groups (atrophic, normal weight and hypertrophic), each constituting about one-third of the total cases. Cardiac atrophy was most frequent in the older cases of more than 20 years of age, whereas hypertrophy was more frequent in younger cases with the highest incidence in cases under 15 years. The liver showed marked atrophy in most cases (144 of 178 cases). The incidence of liver atrophy increased with the age of the patients and all 55 patients of over 20 years of age had an abnormally small liver. These marked atrophies of the heart and liver appeared to have occurred in parallel with loss of body weight due to skeletal muscle wasting. Myocardial dystrophy might be another causative factor for cardiac atrophy. The myocardial hypertrophy seemed to be caused by an intercurrent congestive failure. Renal atrophy was observed in only a few of the extremely emaciated patients. The brain weight was within the normal range in most cases.