α-methylacetoaceticaciduria

α-meth·yl·ac·e·to·ace·tic·ac·id·uria (meth″əl-ə-se″to-ə-se″tik-as″ĭ-duґre-ə) an autosomal recessive aminoacidopathy due to deficiency of α-methylacetoacetyl CoA thiolase, the β-ketothiolase catalyzing the final step in isoleucine catabolism; it is characterized by episodes of severe metabolic ketoacidosis and urinary excretion of several intermediates of isoleucine catabolism, including α-methylacetoacetic acid.