Screening System Detects Four Metabolic Disorders

By LabMedica International staff writers
Posted on 15 Feb 2017
Lysosomal Storage Disorders (LSDs) are a group of rare, inherited metabolic disorders in which enzymes (proteins) that normally eliminate unwanted substances in the body’s cells are not at normal levels or functioning properly. If not detected and treated in a timely manner, these disorders may cause organ damage, neurological disability or death.

A screening test for newborns that is designed to detect Mucopolysaccharidosis Type I (MPS I), Pompe disease, Gaucher disease and Fabry disease has received permission for marketing for these four LSDs. These four LSDs occur in approximately 1 in 1,500 to no more than 1 in 185,000 newborns and children, depending on the disorder.

Image: The SEEKER workstation, a high throughput laboratory solution that measures enzymatic activity from dried blood spot specimens (Photo courtesy of Baebies).

The US Food and Drug Administration evaluated data from a clinical study of 154,412 newborns in Missouri whose dried blood samples were tested for protein activity associated with MPS I, Pompe, Gaucher and Fabry. Efficacy was determined because the system was able to accurately identify at least one of each of these four LSDs in 73 of the screened newborns.

The FDA reviewed the data for the Seeker System through the de novo premarket review pathway, a regulatory pathway for devices of a new type with low-to-moderate-risk that are not substantially equivalent to an already legally marketed device and for which special controls can be developed, in addition to general controls, to provide a reasonable assurance of safety and effectiveness of the devices.

The Seeker System, consisting of the Seeker LSD Reagent Kit- IDUA|GAA|GBA|GLA and Seeker Instrument, works by measuring the activity level of proteins required for healthy lysosomal storage found in dried blood samples collected from the prick of a newborn’s heel 24 to 48 hours after birth. The Seeker Instrument is a device that automates the analysis of dried blood spots. Reduced enzyme activity of proteins associated with any of the four LSDs detected by the kit may indicate presence of a disorder. Results showing reduced enzyme activity must be confirmed using other testing methods, such as biopsies, genetic and other laboratory tests.

Alberto Gutierrez, Ph.D., director of the FDA Office of In Vitro Diagnostics and Radiological Health, said, “The Secretary of HHS recently added Pompe and MPS I to the list of routine recommended newborn screening programs and it is anticipated that additional states will begin requiring use of screening tests to detect these disorders. Accurate screening tests will help with early detection, treatment and control of these rare disorders in newborns, before permanent damage occurs. That’s why availability of LSD screening methods that have been assessed for accuracy and reliability by the FDA are so important.”


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