Biotin-Responsive Alopecia and Developmental Regression

The document described cases of biotin-responsive alopecia and developmental regression, focusing on a 10-month-old boy with dermatitis, alopecia, and severe hypotonia. Laboratory tests indicated a metabolic disorder, and treatment with oral biotin (5 mg twice daily) led to significant improvements, including hair regrowth and regained motor functions. The study emphasized the importance of biotin in treating certain metabolic disorders and suggested further research into biotin and B vitamins' roles in immune function. It also noted that some patients had a generalized defect in biotin metabolism, which could be restored with biotin, and suggested that the abnormalities might be due to defects in biotin absorption or transport rather than dietary deficiency.