Transient tyrosinemia presenting as lactic acidosis in a term baby: report of one case.

Tyrosinemia is one of the disorders of aromatic amino acid metabolism. The report describes a male newborn who presented with tachypnea, lethargy, diarrhea and metabolic acidosis at 12 days old, with an elevated level of lactic acid. Tyrosinemia was impressed according to elevated plasma tyrosine level and specific metabolites of tyrosine detected by gas chromatography/mass spectrometry (GC/MS) study. The symptoms/signs subsided within one month after supportive treatment and protein restriction. Transient tyrosinemia of the newborn is indicative of delayed maturation of the liver enzyme systems (i.e. p-hydroxyphenylpyruvate dioxygenase), and is not a true inborn error of metabolism. Lactic acidosis is a rare associated findings in this condition.