Methods for a prompt and reliable laboratory diagnosis of Pompe disease: report from an international consensus meeting.

Published

Journal Article

Pompe disease is an autosomal recessive disorder of glycogen metabolism caused by a deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). It presents at any age, with variable rates of progression ranging from a rapidly progressive course, often fatal by one-year of age, to a more slowly, but nevertheless relentlessly progressive course, resulting in significant morbidity and premature mortality. In infants, early initiation of enzyme replacement therapy is needed to gain the maximum therapeutic benefit, underscoring the need for early diagnosis. Several new methods for measuring GAA activity have been developed. The Pompe Disease Diagnostic Working Group met to review data generated using the new methods, and to establish a consensus regarding the application of the methods for the laboratory diagnosis of Pompe disease. Skin fibroblasts and muscle biopsy have traditionally been the samples of choice for measuring GAA activity. However, new methods using blood samples are rapidly becoming adopted because of their speed and convenience. Measuring GAA activity in blood samples should be performed under acidic conditions (pH 3.8-4.0), using up to 2 mM of the synthetic substrate 4-methylumbelliferyl-alpha-D-glucoside or glycogen (50 mg/mL), in the presence of acarbose (3-9 microM) to inhibit the isoenzyme maltase-glucoamylase. The activity of a reference enzyme should also be measured to confirm the quality of the sample. A second test should be done to support the diagnosis of Pompe disease until a program for external quality assurance and proficiency testing of the enzymatic diagnosis in blood is established.

Full Text

Duke Authors

Cited Authors

  • Pompe Disease Diagnostic Working Group, ; Winchester, B; Bali, D; Bodamer, OA; Caillaud, C; Christensen, E; Cooper, A; Cupler, E; Deschauer, M; Fumić, K; Jackson, M; Kishnani, P; Lacerda, L; Ledvinová, J; Lugowska, A; Lukacs, Z; Maire, I; Mandel, H; Mengel, E; Müller-Felber, W; Piraud, M; Reuser, A; Rupar, T; Sinigerska, I; Szlago, M; Verheijen, F; van Diggelen, OP; Wuyts, B; Zakharova, E; Keutzer, J

Published Date

  • March 2008

Published In

Volume / Issue

  • 93 / 3

Start / End Page

  • 275 - 281

PubMed ID

  • 18078773

Pubmed Central ID

  • 18078773

Electronic International Standard Serial Number (EISSN)

  • 1096-7206

Digital Object Identifier (DOI)

  • 10.1016/j.ymgme.2007.09.006

Language

  • eng

Conference Location

  • United States