描述
Biotinidase deficiency (Multiple carboxylase deficiency) is an autosomal recessive disease caused by a mutation in the BTD gene which codes for biotinidase. A deficiency in this enzyme results in accumulation of ammonia and ketone bodies in blood; 3-hydroxyisovaleric acid in plasma, spinal fluid, and urine; hydroxypropionic acid, 2-hydroxybutyric acid, 3-Hydroxybutyric acid, and citric acid in spinal fluid; and 3-methylcrotonylglycine, hydroxypropionic acid, and L and D-lactic acid in urine. Symptoms, which can present from birth into adulthood include hypotonia, ketosis, hyperammonemia, motor retardation, coma, and seborrhoic skin rash. Treatment includes biotin.