title: Biotin deficiency in an infant fed with amino acid formula.
abstract: Biotin deficiency is rarely encountered in an infant on weaning from breast and formula feeding. It is characterized by alopecia and scaly, erythematous dermatitis distributed around the body orifices. We report a 5-month-old Japanese infant with typical skin lesions who had been diagnosed as a neonate with dyspepsia and fed only an amino acid formula. Serum and urine levels of biotin were below the normal range, but zinc and biotinidase were within normal range. Urinary excretion of 3-methylcrotonylglycine, 3-hydroxyisovaleric acid, and methylcitric acid was significantly elevated. Daily oral supplementation with 1 mg of biotin resulted in dramatic improvement of the periorificial dermatitis and hair growth together with a complete disappearance of the organic aciduria. Our case shows that the characteristic skin manifestations are the most important clue to the diagnosis of biotin deficiency and demonstrated that urinary excretion of biotin and organic aciduria, rather than the serum concentration of biotin, are the sensitive indicators for evaluating the patient's status of biotin deficiency.
authors.affiliation: Department of Dermatology, Kawasaki Medical School, Kurashiki, Okayama 701-1092, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Fujimoto
authors.forename: Makoto
authors.initials: M
authors.lastname: Inaoki
authors.forename: Toru
authors.initials: T
authors.lastname: Fukui
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Inoue
authors.forename: Tomiko
authors.initials: T
authors.lastname: Kuhara
mesh_terms: D001710:Biotin / Q000008:administration & dosage / Q000097:blood / Q000172:deficiency* / Q000652:urine; D003677:Deficiency Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D019587:Dietary Supplements; D004890:Erythema / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D005148:Facial Dermatoses / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D006801:Humans; D007223:Infant; D041943:Infant Formula; D008297:Male; D010537:Peritoneum
chemical_list: D001710:Biotin