Newborn Screening for Lysosomal Storage Disorders: Quo Vadis?

Abstract

Screening newborns for lysosomal storage disorders (LSDs)7 has gained credence due to the increasing number of therapeutic options available and evidence that early intervention significantly improves outcomes. LSDs are progressive conditions that are typically asymptomatic at birth, potentially making them ideal candidates for newborn screening (NBS). Over the past decade, the development of high-throughput assays with multiplexing capabilities for use with dried blood spot (DBS) samples has facilitated several pilot NBS programs for LSDs worldwide. Such programs have been invaluable in providing knowledge of these disorders, particularly in regards to their true incidence and the overall feasibility of widespread population screening for LSDs. Despite these endeavors, implementation of NBS for LSDs is still debated and there are lingering concerns in some quarters. In the US, the US Department of Health and Human Services Secretary's Advisory Committee on Heritable Disorders in Newborns and Children (SACHDNC) is responsible for reviewing evidence and making recommendations for proposed conditions to be added to the Recommended Universal Screening Panel (RUSP). However, each state determines whether or not it will follow the recommendations. Outside the US, the process is less systematic, and regional newborn screening committees determine which disorders should be added to a panel. The original criteria of Wilson and Jungner (WHO; 1968) for population screening should be used wherever possible as a guide. In general, disorders are considered if they meet criteria based on the following: screening should provide clear benefits to the patient; testing capabilities should be in place; and effective treatments should be available. Despite the technical advances achieved in assay development, there are concerns about the appropriateness of NBS for some LSDs on the basis of the interpretation of results, the need for confirmatory testing, availability of effective therapies, and the overall costs involved. At present, the SACHDNC has recommended …