Brain morphology in Duchenne muscular dystrophy: a Golgi study

Intellectual impairment associated with Duchenne muscular dystrophy is well recognized, although no consistent anatomic central nervous system lesions have been reported. The autopsy findings of 13 patients, ages 13-18 years, were reviewed. Intelligence quotients, ascertained in 5 patients, ranged from 46-79. Gross and microscopic examinations of brain and spinal cord revealed no consistent pattern of abnormalities. Neuropathology included neuronal loss and gliosis in spinal gray matter and tegmental brainstem, extensive Purkinje cell loss, mononuclear perivascular cuffing with cortical and subcortical gliosis, and cerebral heterotopia. Quantitative analysis of rapid Golgi impregnations of the visual cortex revealed significantly reduced dendritic length and branching of apical and basal dendrites from pyramidal neurons in 1 patient and less striking attenuation of dendritic arborization in 2 others. The literature suggests that the intellectual deficit in Duchenne muscular dystrophy is nonprogressive and unrelated to age or severity of muscle disease, although performance intelligence quotient may deteriorate with progressive muscle weakness. Golgi analysis suggested that abnormal dendritic development and arborization may underlie intellectual impairment. Although the pathogenesis of the cellular defect is not fully known, the coexistence of central nervous system and muscle pathology raises the possibility of a common molecular mechanism.