Myopathy in Gaucher disease.

Gaucher disease is a recessively inherited lysosomal storage disorder, caused by deficiency of glucocerebrosidase activity. Affected individuals usually present with hepatosplenomegaly, anaemia, thrombocytopenia, and skeletal diseases. A wide range of neurological manifestations have also been recognized in Gaucher patients including acute neurological deterioration in infancy, mental retardation, ocular motor apraxia, seizure, and parkinsonism. Although muscle weakness is not an uncommon finding in patients with Gaucher disease, the aetiology of weakness is not well understood. We prospectively investigated seven Gaucher patients and found that four of them (patients 1-4) had mild to moderate degree of proximal-predominant symmetrical muscle weakness in four limbs. By history, three patients (patients 1-3) developed insidious onset of nonprogressive muscle weakness in four limbs with easy muscle fatigue from adolescence. A needle electromyographic study detected some small, brief polyphasic waves in these four patients. Muscle biopsy in one patient (patient 1) showed a few atrophic type II muscle fibres without infiltration of Gaucher cells. Three patients (patients 1-3) continuously received enzyme replacement therapy with imiglucerase and their muscle strength seemed improved after two years. We concluded that Gaucher disease may be associated with myopathy.