Possible involvement of partial biotinidase deficiency in alopecia areata

Background: The many factors which appear to be implicated in alopecia areata (AA) include genetic and autoimmune disorders as well as emotional stress. Biotinidase deficiency, an inborn error of metabolism, causes alopecia in infants, children and adults. Subjects and methods: A fluorimetric method was used to evaluate biontinidase activity in 19 patients before and after 40 days treatment with biotin (20 mg/day p.o.). Nineteen members of the medical staff were the controls. Results: The mean biotinidase activities in our patients before treatment (3.0 ± 1.50 mmol/l/min) were statistically significantly decreased compared to those of controls (4.75 ± 0.80 mmol/l/min) as well as to those after treatment (4.40 ± 0.84 mmol/l/min). Consequently, 12 of our 19 patients showed a clinical remission of the disease after treatment, and thin white hair appeared on the frontal area of the scalp. Conclusions: An evaluation of biotinidase activity is suggested in all patients with AA and supplements of biotin are recommended.