Biotin Deficiency in an Infant Fed with Amino Acid Formula and Hypoallergenic Rice

An 11-month-old Japanese infant developed biotin deficiency after being fed an amino acid formula and hypoallergenic rice due to allergies to cow milk and soy. The formula, produced in Japan, lacked biotin supplementation because biotin was not allowed as a food additive. Despite normal levels of zinc, essential fatty acids, and biotinidase, the infant's biotin levels were low, leading to symptoms such as skin lesions, lethargy, hypotonia, and alopecia. These symptoms resolved after one week of oral biotin supplementation at 1 mg per day. The study concluded that biotin should be added to the Japanese amino acid formula to prevent deficiency.