Trivedi M, Zafar S, Spalding M J, Jonnalagadda S
Division of Gastroenterology, University of Missouri-Columbia, Columbia, Missouri, USA.
J Clin Gastroenterol. 2001 Apr;32(4):340-3. doi: 10.1097/00004836-200104000-00013.
Ornithine transcarbamylase (OTC) is a mitochondrial-matrix enzyme that catalyzes conversion of ornithine and carbamyl phosphate to citrulline, the second step in the urea cycle. The urea cycle is the most important pathway to detoxification of ammonia in human beings. Ornithine transcarbamylase deficiency (OTCD) is the most common urea cycle disorder, inherited as an X-linked disorder that can cause fatal hyperammonemia in male newborns. Women with OTCD have a variable expression of their disease, the variability being determined by lyonization (random inactivation) of the X chromosome. We report a case of a 28-year-old woman who presented with hyperammonemic encephalopathy that was precipitated by a gastrointestinal bleed unmasking OTCD.
鸟氨酸转氨甲酰酶（OTC）是一种线粒体基质酶，催化鸟氨酸和氨甲酰磷酸转化为瓜氨酸，这是尿素循环的第二步。尿素循环是人体氨解毒的最重要途径。鸟氨酸转氨甲酰酶缺乏症（OTCD）是最常见的尿素循环障碍，作为一种X连锁疾病遗传，可导致男性新生儿致命性高氨血症。患有OTCD的女性疾病表现具有变异性，这种变异性由X染色体的莱昂化（随机失活）决定。我们报告了一例28岁女性病例，该患者因胃肠道出血诱发高氨血症性脑病，从而揭示了OTCD。
