Muscle pathology in Marinesco-Sjögren syndrome.

Three of 4 adult patients with Marinesco-Sjögren syndrome (MSS; 2 males and 2 females, aged 26-31 years) in 2 families became non-ambulant because of slowly progressive muscular weakness rather than cerebellar ataxia. Other clinical features in these 4 patients were typical for MSS: bilateral cataracts from infancy, mental retardation, severe cerebellar atrophy, multiple skeletal abnormalities and hypergonadotropic hypogonadism. EMG demonstrated a myopathic pattern and serum CK was mildly elevated. Muscle biopsies from these 3 patients showed myopathic changes including a marked variation in fiber size, an increased number of fibers with centralized nuclei, and scattered necrotic and regenerating fibers. Fiber type analysis with myosin ATPase staining showed type 1 fiber predominance, type 2B fiber deficiency and mild increase in type 2C fibers. Muscle biopsy changes and the clinical course indicate that our MSS patients suffered from a chronic dystrophic process similar to that in congenital muscular dystrophy.