An audit of newborn screening procedure: impact on infants presenting clinically before results are available.

Background And Objective: Tandem mass spectrometry-based newborn screening (NBS) is a powerful screening tool. The NBS process includes sample collection, shipment, testing, analysis, reporting and communication with the infant's family. We explored the NBS programme-related factors that may delay diagnosis and may influence timely initiation of treatment in neonates who present before the screening results are available and therefore urgently need diagnosis and treatment.

4-hydroxyglutamate is a biomarker for primary hyperoxaluria type 3.

Primary hyperoxaluria type 3 (PH3) is a recently identified inborn error of 4-hydroxyproline metabolism causing kidney stone disease. Diagnosis to date has relied on mutation detection. The excretion of 4-hydroxyglutamate (4OHGlu) was investigated in controls and a cohort of nine patients with PH3 and their parents using flow injection tandem mass spectrometry.