Four clinical chemistry analyses for pediatric patients: glycosylated hemoglobin, free bilirubin, sweat electrolytes, neonatal thyroxine.

Laboratory methods evaluating pediatric patients for diabetes mellitus, cystic fibrosis, kernicterus and congenital hypothyroidism lack standardization of analyte and/or methodology. While these are the more common metabolic disorders of children the problems of the methods may result in improper diagnosis and treatment. In addition to standardization problems, glycosylated hemoglobin, free bilirubin and blood spot thyroxine have problems in analyte stability, critical testing steps and/or result interpretation. Sweat electrolytes and blood spot thyroxine require very regimented specimen collection. Other pediatric onset diseases may alter the results of glycosylated hemoglobin and free bilirubin. This review article discusses each of these analytes, methodology, problems and usefulness.