Skin biopsy findings in glycogenosis III: Clinical, biochemical, and electrophysiological correlations

Abstract

Electron microscopy of skin specimens was performed in 4 patients (age range, 7 months-40 years) with glycogenosis III and revealed consistent abnormalities. Massive glycogen storage was observed in epithelial secretory cells of eccrine sweat glands and, less markedly, in smooth muscle fibers from the erector pili. Other cells, including Schwann cells of myelinated and unmyelinated fibers, were not affected. The extent of glycogen storage was similar in all patients and unrelated to age or duration of disease. The extralysosomal nature and selectivity of glycogen deposits, sparing fibroblasts and other cells, differ clearly from the findings in skin from patients with glycogenosis II. The purpose of this study was to show that glycogen deposits in glycogenosis III are not restricted to skeletal muscle and liver, and to assess the usefulness of skin biopsy in this disorder.

Polyglucosan body disease myopathy: An unusual presentation

“…In addition to the findings of myopathic motor unit potentials, the presence of abnormal discharges on needle EMG testing, as reported in glycogen storage disorders due to acid maltase 2 and debrancher enzyme deficiency, 14 were also evident in the present case. We found complex repetitive discharges in this case of adult-onset PBD myopathy.…”

Lipoid proteinosis. A biochemical and ultrastructural investigation of two new cases

“…A third sterile sample of unaffected skin was cultured by standard methods and ®broblasts maintained in culture as previously described. 13,14 Incorporation of sodium sulphate 35 S in mucopolysaccharides and determination of intracellular 35 SO 4 -labelled mucopolysaccharides were established following the methods of Fratantoni et al 15 Protein was determined by the method of Lowry et al 16 Arylsulphatase A and B activity was determined using the chromogenic substrate p-nitrocatechol sulphate (Sigma, St Louis, MO, U.S.A.). Other lysosomal activities were determined with arti®cial¯uorescent substrates derived from 4-methylumbelliferone (Sigma).…”