Organic Acid Analysis on Urine Sample Obtaine3d from Dried Filter Paper in Newborns: Development of Screening Method for Organic Aciduria in Neborns

ABSTRACT

PURPOSE: Neonatal screening for inherited metabolic disease is aimed at identifying affected infants early, thus permitting medical intervention to prevent or minimize the effect of the disease. However, organic aciduria, most of which causes severe disease and mental retardation, is not yet screened routinely because of the difficulty of tests, sample collection, and expenditure of time and financial resources. This study was designed to develop a screening method for the detection of multiple organic aciduria and neuroblastoma, using dried urine filter paper. METHODS: The standard markers used for screening of organic aciduria were placed on the filter paper and analysed with the modified organic acid analysis method. The extraction efficiency and stability of standard markers were tested for the purpose of adequacy as screening markers, and the method described herein was evaluated by analyzing filter paper samples obtained from both normal newborns and patients with known organic aciduria. RESULTS: The standard markers in the filter paper left in the room temperature over a period of 5 days were still stable without significant degradation. The level of specific organic acids obtained from known organic aciduria patients were easily detectable-enough to make the diagnosis. CONCLUSION: The filter papers soaked with urines obtained from newborns or patients with suspicious metabolic diseases are adequate for screening of organic acidurias and neuroblastoma. Sample delivery to the laboratory can be handled more easily with this method and even newborn screening could be applied in the future.