Determination of amino acid profile for argininosuccinic aciduria disorder using High-Performance Liquid Chromatography with fluorescence detection

Argininosuccinic aciduria is an autosomal, recessive amino acid disorder that is caused by a deficiency of the argininosuccinate lyase enzyme. Citrulline is the most significant marker to detect this disorder. We used the High-performance liquid chromatography with fluorescence detection with 450 nm emission and 330 nm excitation wavelengths, 15 mmol/L potassium dihydrogen phosphate and 5 mmol/L dipotassium hydrogen phosphate as Mobile Phase A, and 50 mL water, 250 mL acetonitrile, and 200 mL methanol as Mobile Phase B in gradient mode with flow rate of 1.2 mL/min. The citrulline concentration was 22 µmol/L in healthy infants and 220 µmol/L in infants suffering from the disorder.

A Severe Neonatal Argininosuccinic Aciduria Case Investigated by 1H NMR Spectroscopy

The NMR urine analysis of a term newborn with severe general deterioration of the clinical state revealed the presence in high concentrations of orotic and argininosuccinic acids. The newborn was suspected for an intoxication-like inborn error of metabolism, and the urine samples were followed up by NMR spectroscopy for several days in order to assess the metabolic pattern. The identified markers led to a definitive biochemical diagnosis of argininosuccinic aciduria.