%0 Case Reports
%T Holocarboxylase synthetase deficiency: report of one case.
%A Chou IC
%A Wang CS
%A Lin WD
%A Lin HC
%A Tsai CH
%A Wang TR
%A Tsai FJ
%J Acta Paediatr Taiwan
%V 47
%N 6
%D Nov-Dec 2006
%M 17407983
暂无%X Holocarboxylase synthetase (HCS) is an enzyme that catalyzes biotin incorporation into carboxylases, and its deficiency causes biotin-responsive multiple carboxylase deficiency. We report a patient who had his first episode at 32 months of age. The main clinical findings were a characteristic rash, projectile vomiting, progressive consciousness loss, organophosphate order, and hypotension. Laboratory examinations showed metabolic acidosis with ketolactic acidosis, hyperammonemia, and urine organic acid profile suggestive of a biotin utilization abnormality consistent with multiple carboxylase deficiency. Nucleotide sequence analysis of the biotinidase gene of the patient revealed negative finding, however, analysis of HCS gene found a homozygous 1809C->T (R508W) mutation. R508W is a rare mutation in Taiwanese HCS deficiency patients, which is associated with the late-onset phenotype. The patient responded dramatically to biotin, and has remained normal growth and development during more than three years of follow-up. Therefore, a high index of suspicion for timely diagnosis and treatment could prevent severe complications.