Familial Protein Intolerance

Abstract

Thirteen cases of "familial protein intolerance," a hereditary defect in ammonium ion metabolism, have occurred in Finland. The nature of the metabolic defect has remained obscure. In a patient displaying clinical and biochemical features of "familial protein intolerance," but without documented familial occurrence, the main clinical features were intellectual impairment, with x-ray evidence of brain atrophy, and marked skeletal fragility. Intolerance to protein-containing foods was moderate. The postprandial blood ammonia concentration was moderately elevated, whereas intravenous L-alanine administration caused marked ammonia elevation as well as marked hyperglycemia.