High blood pressure, a red flag for the neonatal manifestation of urea cycle disorders | Orphanet Journal of Rare Diseases | Full Text

High blood pressure, a red flag for the neonatal manifestation of urea cycle disorders | Orphanet Journal of Rare Diseases | Full Text

Orphanet Journal of Rare Diseases

High blood pressure, a red flag for the neonatal manifestation of urea cycle disorders

• Ulrike TeufelEmail author,
• Peter Burgard,
• Jochen Meyburg,
• Martin Lindner,
• Johannes Poeschl,
• Peter Ruef,
• Georg F. Hoffmann and
• Stefan Kölker

Orphanet Journal of Rare Diseases201914:80

https://doi.org/10.1186/s13023-019-1055-z

©  The Author(s). 2019

• Received: 8 December 2018
• Accepted: 1 April 2019
• Published: 8 April 2019

Abstract

Background

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 (NH4+) concentration, mode of emergency treatment and transfer to a tertiary referral center on the outcome.

Methods

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.

Results

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 NH4+concentrations further increased despite initiation of metabolic therapy.

Conclusion

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.

Keywords

• Neonatal urea cycle disorders
• Hypertension
• Clinical presentation
• Hyperammonemic encephalopathy