Case Definitions


A set of case definitions has been developed by the newborn screening community to facilitate common classifications for diagnoses across programs for all of the core newborn screening conditions. These definitions have been developed through an iterative process by experts in state newborn screening programs. They have also been piloted in newborn screening programs and integrated into the NewSTEPs Data Repository. Consensus public health surveillance case definitions for newborn screening disorders will allow for consistent categorization and tracking of short and long-term follow-up of identified newborns at the local, regional and national levels.

Arginase deficiency

ClassificationPlasma amino acidsMutation analysisEnzyme Studies
Definite2 known disease causing variants in the same gene (Allele 1 ? variant known to be disease causing and Allele 2 ? variant known to be disease causing)
DefiniteEnzyme analysis consistent with Arginase deficiency
ProbableElevated Arginine1 known disease causing mutation
PossibleElevated Arginine

Argininosuccinic aciduria (ASA)

ClassificationPlasma or urine amino acidsMutation analysisEnzyme Studies
DefiniteUntested or unknown2 known disease causing mutations in the same geneUntested or unknown
DefiniteUntested or unknownUntested or unknownEnzyme analysis consistent with ASA
-ASA and
Untested or unknownUntested or unknown
DefiniteElevated ASA2 mutations of uncertain significance in the same gene - predicted to be pathogenicUntested or unknown
PossibleElevated Citrulline1 known disease causing mutationUntested or unknown
PossibleElevated Citrulline2 mutations of uncertain significance in the same geneUntested or unknown