An approach to the diagnosis of overwhelming metabolic disease in early infancy.

Heritable metabolic disease is a significant cause of overwhelming illness in the very young infant. It appears that most patients with well recognized disorders are not being diagnosed, and it is our conviction that there are new, as yet unidentified, inborn errors of metabolism in this population of patients. We have attempted to develop a systematic approach to the seriously ill newborn as a candidate for an early diagnosis of metabolic disease. There are some clinical clues that suggest the presence of disordered metabolism. The laboratory can be useful in confirming initial clinical suspicions and in screening for the presence of abnormality. The complexity of laboratory evaluation increases as one proceeds to definitive diagnosis and modern organic analysis.