Clinical background of newborn screening

Newborn screening is a preventive measure to detect the genetic metabolic deficiency. Free carnitine and acylcarnitines are markers for fatty acid oxidation (FAO) disorders or organic aciduria (OA) and amino acids are marker for amino acidopathies.

Fatty acid oxidation (FAO) disorders

Fatty acid oxidation disorders, are a group of about 20 defects in fatty acid transport and mitochondrial β-oxidation that are inherited as autosomal recessive disorders. FAO disorders are caused by a lack or deficiency of the enzymes needed to break down or oxidation of fatty acids, resulting in delayed mental and physical development.

Organic aciduria (OA) disorders

Organic acidurias (OA) are an important class of inherited metabolic disorders arising due to defect in intermediary metabolic pathways of carbohydrate, amino acids and fatty acid oxidation. It leads to accumulation of organic acids in tissues and their subsequent excretion in urine, that resulting in numerous clinical symptoms, including metabolic acidosis, ketosis, hyperammonemia, failure to thrive, sepsis or coma.

Amino acidopathies

In this inherited defect is reflected downstream as a lack or a partial biological activity of enzymes involved in amino acids metabolism. As a result, the concentration of the affected amino acids and their metabolites, increases in the infant’s body. These excesses can have severe deleterious effects on the infant’s health including death. Amino acid disorders are managed by medical support and nutritional restrictions, supplements and medical foods that limit consumption of an offending amino acid or in some cases protein consumption.

Intended Use

The PH NBS/PH NBS-D Complete kits are intended for the semi-quantitative measurement and evaluation of amino acids, free carnitine and acylcarnitines concentrations in dried blood samples on the filter paper for newborn screening.

The evaluated values of these analytes and their relationship with each other is intended to provide analyte concentration profiles that interpret metabolic disorder in newborn screening.