Enzymatic and molecular strategies to diagnose Pompe disease.

Enzyme replacement therapy for Pompe disease, a neuromuscular disorder characterized by lysosomal glycogen storage due to acid α-glucosidase deficiency, has entered the clinic. There is more than ever a need for early and reliable diagnosis. The objective of this review is to present a critical review of the recent literature on laboratory procedures to diagnose Pompe disease by enzymatic assay and DNA analysis. The methods we used were Compilation and expert interpretation of recent and relevant publications. The introduction of new and the updating of existing laboratory procedures have facilitated the diagnosis of Pompe disease (glycogen storage disease type II; acid maltase deficiency; OMIM 232300). With regard to enzymatic analysis, the application of acarbose as inhibitor of maltase-glucoamylase has enabled the use of mixed leukocyte preparations as diagnostic material. The use of glycogen as a natural substrate in the reaction mixture adds to the selectivity of this procedure. Newborn screening is envisaged and facilitated by the introduction of high-throughput procedures. DNA analysis has become an integral part of the diagnostic procedure for confirmation and completion, for carrier detection, and for genetic counseling.