Krabbe and Niemann-Pick disorders: Development of novel fluorimetric assays using dried blood spots

Deficiencies in the lysosomal storage enzymes galactocerebrosidase (GALC) and acid sphingomyelinase (ASM) are causative for the devastating metabolic disorders Krabbe and Niemann-Pick, respectively. Neurological symptoms of both disorders often present in infancy and progress quickly. Timely disease detection is therefore a critical component of patient care. Dried blood spot (DBS) cards are the current standard specimen for newborn screening assays in state public health laboratories. Here, we present fluorimetric assays to measure GALC and ASM enzyme activity in dried blood spot specimens. Introduction