A survey of Japanese patients with mitochondrial fatty acid β-oxidation and related disorders as detected from 1985 to 2000

A clinical survey of Japanese patients with mitochondrial fatty acid P-oxidation and related disorders (FAODs) was performed with questionnaires sent to 187 institutions, where inborn errors of metabolism could be managed in Japan, including a search of related literature published between 1985 and 2000. Sixty-four patients with ten types of FAODs were found. Carnitine palmitoyltransferase 2 deficiency and glutaric aciduria type 2 were most common (17 and 14 patients, respectively). As of 2000, there were no patients with medium-chain acyl-CoA dehydrogenase deficiency, which is common in Caucasians. Age at onset was under 2 years in 38 (59%) of the patients. Eight (13%) patients had neonatal onset. Twenty-one (55%) of the 38 children with an initial attack under 2 years of age had acute encephalopathy or a Reye syndrome-like illness. Half of the patients presented within 2 years of birth died or were handicapped. On the other hand, 19 (79%) of the 24 with onset after 2 years of age had muscle symptoms and 23 (96%) of the 24 grew and developed normally. Though the precise incidence of FAODs in Japan is still unknown, as a consequence of the development of diagnostic procedures the number of FAOD cases being diagnosed appears to have increased. Mass screening for FAODs during the neonatal period will greatly aid in prevention of attacks and related effects. (C) 2002 Elsevier Science B.V. All rights reserved.