Pompe disease is a lysosomal storage disorder caused by acid α-glucosidase deficiency and characterized by progressive muscle weakness. Enzyme replacement therapy (ERT) has ameliorated patients' perspectives, but reversal of skeletal muscle pathology remains a challenge. We studied pretreatment biopsies of 22 patients with different phenotypes to investigate to what extent fiber-type distribution and fiber-type-specific damage contribute to clinical diversity. Pompe patients have the same fiber-type distribution as healthy persons, but among nonclassic patients with the same GAA mutation (c.-32-13T>G), those with early onset of symptoms tend to have more type 2 muscle fibers than those with late-onset disease. Further, it seemed that the older, more severely affected classic infantile patients and the wheelchair-bound and ventilated nonclassic patients had a greater proportion of type 2x muscle fibers. However, as in other diseases, this may be caused by physical inactivity of those patients.

dx.doi.org/10.1007/s10545-012-9541-7, hdl.handle.net/1765/37468
Journal of Inherited Metabolic Disease
Erasmus MC: University Medical Center Rotterdam

van den Berg, L.E.M, Drost, M.R, Schaart, G, de Laat, P.C.J, van Doorn, P.A, van der Ploeg, A.T, & Reuser, A.J.J. (2013). Muscle fiber-type distribution, fiber-type-specific damage, and the Pompe disease phenotype. Journal of Inherited Metabolic Disease, 1–8. doi:10.1007/s10545-012-9541-7