Division of Human Genetics, The Children's Hospital of Philadelphia, Colket Translational Research Building, 3501 Civic Center Blvd, Floor 9, 19104, Philadelphia, Pennsylvania, USA.
Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
J Inherit Metab Dis. 2019 Jan;42(1):140-146. doi: 10.1002/jimd.12035.
Glutamate formiminotransferase deficiency (FTCD deficiency) or formiminoglutamic aciduria is the second most common of the known inherited disorders of folate metabolism. Initial case reports suggested that patients may have severe intellectual disability and megaloblastic anemia. However, these cases were obtained from screening cohorts of patients with developmental delay. Subsequently, patients with milder clinical phenotypes have been reported. The full phenotypic spectrum of this disorder remains unknown.
In many states, FTCD deficiency can be incidentally detected on tandem mass spectrometry-based newborn screening of dried blood spots. In this work, we report the outcomes of infants identified to have FTCD deficiency through newborn screening.
During the study period, 18 patients were identified to have FTCD deficiency and were referred and evaluated at one of the two participating metabolic centers. The overall rate of FTCD deficiency detected through the New Jersey screening program over the study time period was 1:58,982. At a mean age of 56 months at last follow-up: 3/18 (16%) had developmental delays requiring individualized education plans, no patients had profound intellectual disability; 4/16 (25%) had mild self-limited anemia, no patients had profound anemia.
These data suggest that the majority of individuals with FTCD deficiency detected by newborn screening are asymptomatic.
谷氨酸 formiminotransferase 缺乏症（FTCD 缺乏症）或 formiminoglutamic 酸尿症是已知的叶酸代谢遗传疾病中第二常见的疾病。最初的病例报告表明，患者可能有严重的智力残疾和巨幼细胞性贫血。然而，这些病例是从发育迟缓患者的筛查队列中获得的。随后，报道了具有更轻微临床表型的患者。该疾病的完整表型谱尚不清楚。
在许多州，FTCD 缺乏症可以通过基于串联质谱的新生儿筛查从干血斑中偶然发现。在这项工作中，我们报告了通过新生儿筛查发现的 FTCD 缺乏症婴儿的结果。
在研究期间，有 18 名患者被确定为 FTCD 缺乏症，并在两个参与的代谢中心之一接受转诊和评估。在研究期间，通过新泽西州筛查计划检测到的 FTCD 缺乏症的总体发生率为 1:58982。在最后一次随访时的平均年龄为 56 个月：3/18（16%）有需要个别化教育计划的发育迟缓，没有患者有严重智力残疾；4/16（25%）有轻度自限性贫血，没有患者有严重贫血。
这些数据表明，通过新生儿筛查检测到的大多数 FTCD 缺乏症患者无症状。
