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.

Biochemical and molecular characteristics of patients with organic acidaemias and urea cycle disorders identified through newborn screening.

Background: In recent years it has become clear that newborn screening (NBS) programmes using tandem mass spectrometry identify "patients" with "classical" inborn errors of metabolism who are asymptomatic. This observation raises issues regarding medicalization of "non-diseases," potentially unnecessary treatment and unnecessary anxiety to parents.

Aims: This study aims to identify possible markers that may assist in predicting the need for treatment of infants with "classical" organic acidaemias (OA) and urea cycle disorders (UCD) diagnosed through NBS.

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.