- 期刊
Holocarboxylase Synthetase Deficiency: Report of One Case
全脫羧酶｜合成酶｜缺乏症：一病例報告
摘要
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.
並列摘要
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.