Evaluation of 700 patients referred with a preliminary diagnosis of biotinidase deficiency by the national newborn metabolic screening program: a single-center experience.

Treatment should be initiated promptly in patients who are referred by the newborn screening program. Any mean activity under 59.5 MRU should be considered partial BD, while less than 50.5 MRU should be considered profound BD. It should be kept in mind that clinical manifestations may develop both in profound and partial BD.