栄養性ビオチン欠乏症と先天性ビオチン代謝異常症の疫学

抄録

Biotin is a water-soluble vitamin and a cofactor of several types of carboxylases. Insufficient intake of biotin and a congenital deficiency of enzymes requiring biotin as a cofactor in cells cause clinical symptoms called multiple carboxylase deficiency (MCD). In recent years, several reports have shown that infants with food allergy and/or atopic eczema have developed MCD after being fed with peptide formulas. Peptide formulas available in Japan contain very little biotin because biotin has not been permitted to be added to regular foods as an additive. This, however, may lead to nutritional biotin deficiency in some infants fed with such a peptide milk. We investigated the incidence of nutritional biotin deficiency and congenital enzyme deficiency in Japan. We sent a questionnaire to 921 hospitals with a pediatric department to cover all areas of Japan. The response rate was 64%. The rate of hospitals that use peptide milk in the therapy of allergic diseases was 49%. The estimated incidence of biotin deficiency was at least 70 cases in the last 10 years. Since the first diagnosis of holocarboxylase synthetase deficiency (HCSD) in 1982, HCSD and biotinidase deficiency have been confirmed in 28 and 2 cases, respectively. These data suggest that the incidence of congenital enzyme deficiency is about 1 case per year. Supplementation of biotin is highly recommended when infants are fed with peptide milk in Japan.