Department of Paediatrics, Rotunda Hospital, Dublin 1, Ireland.
Department of Paediatrics, RCSI, Dublin 2, Ireland.
Eur J Pediatr. 2022 Oct;181(10):3725-3732. doi: 10.1007/s00431-022-04588-4. Epub 2022 Aug 10.
Inborn errors of metabolism are an individually rare but collectively significant cause of mortality and morbidity in the neonatal period. They are identified by either newborn screening programmes or clinician-initiated targeted biochemical screening. This study examines the relative contribution of these two methods to the identification of inborn errors of metabolism and describes the incidence of these conditions in a large, tertiary, neonatal unit. We also examined which factors could impact the reliability of metabolic testing in this cohort. This is a retrospective, single-site study examining infants in whom a targeted metabolic investigation was performed from January 2018 to December 2020 inclusive. Data was also provided by the national newborn screening laboratory regarding newborn screening diagnoses. Two hundred and four newborns received a clinician-initiated metabolic screen during the time period examined with 5 newborns being diagnosed with an inborn error of metabolism (IEM) (2.4%). Of the 25,240 infants born in the hospital during the period examined, a further 11 newborns had an inborn error of metabolism diagnosed on newborn screening. This produced an incidence in our unit over the time described of 6.34 per 10,000 births. This number reflects a minimum estimate, given that the conditions diagnosed refer to early-onset disorders and distinctive categories of IEM only. Efficiency of the clinician-initiated metabolic screening process was also examined. The only statistically significant variable in requiring repeat metabolic screening was early day of life (z-score = - 2.58, p = 0.0098). A total of 28.4% was missing one of three key metabolic investigation parameters of blood glucose, ammonia or lactate concentration with ammonia the most common investigation missing. While hypoglycemia was the most common clinical rationale for a clinician-initiated metabolic test, it was a poor predictor of inborn error of metabolism with no newborns of 25 screened were diagnosed with a metabolic disorder.
Clinician-targeted metabolic screening had a high diagnostic yield given the relatively low prevalence of inborn errors of metabolism in the general population. Thoughts should be given to the rationale behind each targeted metabolic test and what specific metabolic disease or category of inborn error of metabolism they are concerned along with commencing targeted testing.
• Inborn errors of metabolism are a rare but potentially treatable cause of newborn mortality and morbidity. • A previous study conducted in a tertiary unit in an area with limited newborn screening demonstrated a diagnostic yield of 5.4%.
• Clinician-initiated targeted metabolic screening has a good diagnostic performance even with a more expanded newborn screening programme. • Further optimisation could be achieved by examining the best timing and also the rationale of metabolic testing in the newborn period.
本研究旨在探讨这两种方法对代谢缺陷的识别作用，并描述在一个大型三级新生儿病房中这些疾病的发病率。我们还研究了哪些因素可能影响该队列代谢检测的可靠性。
这是一项回顾性单站点研究，纳入了 2018 年 1 月至 2020 年 12 月期间进行了目标代谢检查的婴儿。国家新生儿筛查实验室还提供了有关新生儿筛查诊断的数据。在研究期间，有 204 名新生儿接受了临床医生发起的代谢筛查，其中 5 名（2.4%）被诊断为代谢缺陷（IEM）。在检查期间出生的 25240 名婴儿中，另有 11 名新生儿在新生儿筛查中被诊断为代谢缺陷。这表明在描述的时间段内，我们单位的发病率为每 10000 例出生 6.34 例。这一数字反映了一个最低估计，因为所诊断的疾病仅指早发性疾病和特定类别的 IEM。我们还检查了临床医生发起的代谢筛查过程的效率。需要重复代谢筛查的唯一具有统计学意义的变量是生命早期的天数（z 分数=-2.58，p=0.0098）。有 28.4%的患者缺少血糖、氨或乳酸浓度三种关键代谢检查参数中的一种，其中氨是最常见的检查缺失项目。尽管低血糖是临床医生发起代谢测试的最常见理由，但它并不能很好地预测代谢缺陷，在接受筛查的 25 名新生儿中，没有一人被诊断为代谢障碍。
考虑到代谢缺陷在普通人群中的患病率相对较低，临床医生靶向代谢筛查具有较高的诊断率。应该考虑每次靶向代谢测试背后的基本原理，以及它们具体关注的是哪种代谢疾病或代谢缺陷类别，并开始靶向测试。
·代谢缺陷是新生儿死亡率和发病率的一个罕见但潜在可治疗的原因。·之前在一个新生儿筛查范围有限的三级单位进行的一项研究显示诊断率为 5.4%。
·临床医生发起的靶向代谢筛查具有良好的诊断性能，即使在扩大了新生儿筛查计划的情况下也是如此。·通过检查新生儿期代谢检测的最佳时机和基本原理，还可以进一步优化。
