Center for Child and Adolescent Medicine, Division of Pediatric Neurology and Metabolic Medicine, University Hospital Heidelberg, Heidelberg, Germany.
Department of General Pediatrics, Adolescent Medicine and Neonatology, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Orphanet J Rare Dis. 2019 Apr 8;14(1):80. doi: 10.1186/s13023-019-1055-z.
Neonatal manifestation of life-threatening hyperammonemic encephalopathy in urea cycle disorders (UCD) is often misdiagnosed as neonatal sepsis, resulting in significantly delayed start of specific treatment and poor outcome. The major aim of this study was to identify specific initial symptoms or signs to clinically distinguish hyperammonemic encephalopathy in neonates from neonatal sepsis in order to identify affected individuals with UCD and to start metabolic therapy without delay. Furthermore, we evaluated the impact of diagnostic delay, peak plasma ammonium (NH) concentration, mode of emergency treatment and transfer to a tertiary referral center on the outcome.
Detailed information of 17 patients (born between 1994 and 2012) with confirmed diagnosis of UCD and neonatal hyperammonemic encephalopathy were collected from the original medical records.
The initially suspected diagnosis was neonatal sepsis in all patients, but was not confirmed in any of them. Unlike neonatal sepsis and not previously reported blood pressure increased above the 95th percentile in 13 (81%) of UCD patients before emergency treatment was started. Respiratory alkalosis was found in 11 (65%) of UCD patients, and in 14 (81%) plasma NHconcentrations further increased despite initiation of metabolic therapy.
Detection of high blood pressure could be a valuable parameter for distinguishing neonatal sepsis from neonatal manifestation of UCD. Since high blood pressure is not typical for neonatal sepsis, other reasons such as encephalopathy and especially hyperammonemic encephalopathy (caused by e.g. UCD) should be searched for immediately. However, our result that the majority of newborns with UCD initially present with high blood pressure has to be evaluated in larger patient cohorts.
尿素循环障碍（UCD）患者发生危及生命的高氨血症性脑病的新生儿表现常被误诊为新生儿败血症，导致特异性治疗明显延迟，预后不良。本研究的主要目的是确定特定的初始症状或体征，以便从临床上区分新生儿高氨血症性脑病与新生儿败血症，从而识别出 UCD 患者，并立即开始代谢治疗。此外，我们还评估了诊断延迟、血浆铵（NH）峰值浓度、紧急治疗方式和转至三级转诊中心对结局的影响。
从原始病历中收集了 17 名（1994 年至 2012 年出生）确诊为 UCD 和新生儿高氨血症性脑病患者的详细信息。
所有患者最初的疑似诊断均为新生儿败血症，但均未得到证实。与新生儿败血症不同，在开始紧急治疗前，13 名（81%）UCD 患者的血压高于第 95 百分位，这在之前并未报道过。11 名（65%）UCD 患者存在呼吸性碱中毒，14 名（81%）患者尽管开始代谢治疗，但血浆 NH 浓度仍进一步升高。
检测高血压可能是区分新生儿败血症与 UCD 新生儿表现的有价值参数。由于高血压并非新生儿败血症的典型表现，因此应立即寻找其他原因，如脑病，特别是高氨血症性脑病（例如由 UCD 引起）。然而，我们的研究结果表明，大多数患有 UCD 的新生儿最初表现为高血压，这需要在更大的患者队列中进行评估。
