Dietary correction of histidinemia in older children possible

It has been shown that dietary restriction of histidine in a nearly 11 years old histidinemic boy resulted in a complete correction of serum histidine and urinary imidazoles, despite histidine is considered to be a non-essential amino acid in man at higher age. Normalization took more time than in younger children and restriction had to be more drastic. Apparently older children are less dependent on exogenous histidine than are younger ones. Serum histidine and urinary histidine, N-acetyl-histidine, imidazolepyruvic, imidazolactic and imidazoleacetic acids were determined throughout the whole period of histidine restriction. The patient's EEG abnormalities did not improve after normalization of serum histidine. The desirability of treatment in histidinemia is discussed.