Skip to main content
Log in

Age at disease onset and peak ammonium level rather than interventional variables predict the neurological outcome in urea cycle disorders

  • Original Article
  • Published:
Journal of Inherited Metabolic Disease

    We’re sorry, something doesn't seem to be working properly.

    Please try refreshing the page. If that doesn't work, please contact support so we can address the problem.

A Correction to this article was published on 12 January 2018

This article has been updated

Abstract

Background

Patients with urea cycle disorders (UCDs) have an increased risk of neurological disease manifestation.

Aims

Determining the effect of diagnostic and therapeutic interventions on the neurological outcome.

Methods

Evaluation of baseline, regular follow-up and emergency visits of 456 UCD patients prospectively followed between 2011 and 2015 by the E-IMD patient registry.

Results

About two-thirds of UCD patients remained asymptomatic until age 12 days [i.e. the median age at diagnosis of patients identified by newborn screening (NBS)] suggesting a potential benefit of NBS. In fact, NBS lowered the age at diagnosis in patients with late onset of symptoms (>28 days), and a trend towards improved long-term neurological outcome was found for patients with argininosuccinate synthetase and lyase deficiency as well as argininemia identified by NBS. Three to 17 different drug combinations were used for maintenance therapy, but superiority of any single drug or specific drug combination above other combinations was not demonstrated. Importantly, non-interventional variables of disease severity, such as age at disease onset and peak ammonium level of the initial hyperammonemic crisis (cut-off level: 500 μmol/L) best predicted the neurological outcome.

Conclusions

Promising results of NBS for late onset UCD patients are reported and should be re-evaluated in a larger and more advanced age group. However, non-interventional variables affect the neurological outcome of UCD patients. Available evidence-based guideline recommendations are currently heterogeneously implemented into practice, leading to a high variability of drug combinations that hamper our understanding of optimised long-term and emergency treatment.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

Similar content being viewed by others

Change history

  • 12 January 2018

    Due to an unfortunate error during the typesetting process, the collaborators were presented incorrectly.

Abbreviations

ARG1:

Arginase 1

ASL:

Argininosuccinate lyase

ASS:

Argininosuccinate synthetase

CPS1:

Carbamylphosphate synthetase 1

E-IMD:

European registry and network for intoxication type metabolic diseases

EO:

Early onset

HHH syndrome:

Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome

IR:

Interquartile range

LO:

Late onset

NAGS:

N-acetylglutamate synthase

NBS:

Newborn screening

OR(s):

Odds ratio(s)

OTC:

Ornithine transcarbamylase

Q1:

First quartile

Q3:

Third quartile

UCD(s):

Urea cycle disorder(s)

References

  • Adam S, Almeida MF, Assoun M et al (2013) Dietary management of urea cycle disorders: European practice. Mol Genet Metab 110:439–445

    Article  CAS  PubMed  Google Scholar 

  • Bachmann C (2003a) Outcome and survival of 88 patients with urea cycle disorders: a retrospective evaluation. Eur J Pediatr 162:410–416

    Article  PubMed  Google Scholar 

  • Bachmann C (2003b) Long-term outcome of patients with urea cycle disorders and the question of neonatal screening. Eur J Pediatr 162(Suppl 1):S29–S33

    Article  CAS  PubMed  Google Scholar 

  • Batshaw ML, Tuchman M, Summar M, Seminara J, Members of the Urea Cycle Disorders Consortium (2014) A longitudinal study of urea cycle disorders. Mol Genet Metab 113:127–130

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Berry SA, Lichter-Konecki U, Diaz GA et al (2014) Glycerol phenylbutyrate treatment in children with urea cycle disorders: pooled analysis of short and long-term ammonia control and outcomes. Mol Genet Metab 112:17–24

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Brassier A, Gobin S, Arnoux JB et al (2015) Long-term outcomes in ornithine transcarbamylase deficiency: a series of 90 patients. Orphanet J Rare Dis 10:58. doi:10.1186/s13023-015-0266-1

  • Brusilow SW, Batshaw ML (1979) Arginine therapy of argininosuccinate deficiency. Lancet 1:124–127

    Article  CAS  PubMed  Google Scholar 

  • Brusilow SW, Valle DL, Batshaw M (1979) New pathways of nitrogen excretion in inborn errors of urea synthesis. Lancet 2:452–454

    Article  CAS  PubMed  Google Scholar 

  • Burgard P, Rupp K, Lindner M et al (2012) Newborn screening programmes in Europe; arguments and efforts regarding harmonization. Part 2.From screening laboratory results to treatment, follow-up and quality assurance. J Inherit Metab Dis 35:613–625

    Article  CAS  PubMed  Google Scholar 

  • Burgard P, Kölker S, Haege G, Lindner M, Hoffmann GF (2015) Neonatal mortality and outcome at the end of the first year of life in early onset urea cycle disorders – review and meta-analysis of observational studies published over more than 35 years. J Inherit Metab Dis. doi:10.1007/s10545-015-9901-1

    Google Scholar 

  • R Core Team (2015) R: a language and environment for statistical computing. R Foundation for Statistical Computing. R version 3.2.1. Vienna, Austria, http://www.R-project.org/

  • Crombez EA, Cederbaum SD (2005) Hyperargininemia due to liver arginase deficiency. Mol Genet Metab 84:243–251

    Article  CAS  PubMed  Google Scholar 

  • Enns GM, Berry SA, Berry BT et al (2007) Survival after treatment with phenylacetate and benzoate for urea cycle disorders. N Engl J Med 356:2282–2292

    Article  CAS  PubMed  Google Scholar 

  • FAO (2001) Human energy requirements: report of a joint FAO/WHO/UNU expert consultation. FAO report series, no. 1. FAO, Rome

    Google Scholar 

  • Foster KJ, Lin S, Turck CJ (2010) Current and emerging strategies for treating hepatic encephalopathy. Crit Care Nurs Clin North Am 22:341–350

    Article  PubMed  Google Scholar 

  • Garbade SF, Greenberg CR, Demirkol M et al (2014) Unravelling the complex MRI pattern in glutaric aciduria type I using statistical models-a cohort study in 180 patients. J Inherit Metab Dis 37:763–773

    Article  CAS  PubMed  Google Scholar 

  • Häberle J, Boddaert N, Burlina A et al (2012) Suggested guidelines for the diagnosis and management of urea cycle disorders. Orphanet J Rare Dis 7:32

    Article  PubMed  PubMed Central  Google Scholar 

  • Heinze G, Schemper M (2002) A solution to the problem of separation in logistic regression. Stat Med 21(16):2409–2419

    Article  PubMed  Google Scholar 

  • Heinze G, Ploner M, Dunkler D, Southworth H (2013) Logistf: firth’s bias reduced logistic regression. R package version 1.21, http://CRAN.R-project.org/package=logistf

  • Heringer J, Boy SP, Ensenauer R et al (2010) Use of guidelines improves the neurological outcome in glutaric aciduria type I. Ann Neurol 68:743–752

    Article  PubMed  Google Scholar 

  • Hothorn T, Hornik K, Zeileis A (2006) Unbiased recursive partitioning: a conditional inference framework. J Comput Graph Stat 15(3):651–674

    Article  Google Scholar 

  • Hothorn T, Hornik K, Strobl C, Zeileis A (2015) Party: a laboratory for recursive partitioning. R package version 1.0-23, http://CRAN.R-project.org/package=party

  • Jamiolkowski D, Kölker S, Glahn EM et al (2015) Behavioural and emotional problems, intellectual impairment and health-related quality of life in patients with organic acidurias and urea cycle disorders. J Inherit Metab Dis. doi:10.1007/s10545-015-9887-8

    PubMed  Google Scholar 

  • Kido J, Nakamura K, Mitsubuchi H et al (2012) Long-term outcome and intervention of urea cycle disoerders in Japan. J Inherit Metab Dis 35:777–785

    Article  CAS  PubMed  Google Scholar 

  • Kimura N, Kubo N, Narumi S et al (2013) Liver transplantation versus conservative treatment for adult-onset type II citrullinemia: our experience and a review of the literature. Transplant Proc 45:3432–3437

    Article  CAS  PubMed  Google Scholar 

  • Kölker S, Garbade SF, Greenberg CR et al (2006) Natural history, outcome, and treatment efficacy in children and adults with glutaryl-CoA dehydrogenase deficiency. Pediatr Res 59:840–847

    Article  PubMed  Google Scholar 

  • Kölker S, Christensen E, Leonard JV et al (2011) Diagnosis and management of glutaric aciduria type I--revised recommendations. J Inherit Metab Dis 34:677–694

    Article  PubMed  PubMed Central  Google Scholar 

  • Kölker S, Garcia Cazorla A, Valayannopoulos V et al (2015a) The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 1: the initial presentation. J Inherit Metab Dis 38:1041–1057

    Article  PubMed  Google Scholar 

  • Kölker S, Valayannopoulos V, Burlina AB et al (2015b) The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 2: the evolving clinical phenotype. J Inherit Metab Dis 38:1059–1074

    Article  PubMed  Google Scholar 

  • Kölker S, Dobbelaere D, Häberle J et al (2015c) Networking across borders for individuals with organic acidurias and urea cycle disorders: the E-IMD consortium. JIMD Rep 22:29–38

    Article  PubMed  PubMed Central  Google Scholar 

  • Loeber JG, Burgard P, Cornel MC et al (2012) Newborn screening programmes in Europe; arguments and efforts regarding harmonization. Part 1. From blood spot to screening result. J Inherit Metab Dis 35:603–611

    Article  PubMed  Google Scholar 

  • Martinelli D, Diodato D, Ponzi E et al (2015) The hyperornithinemia-hyperammonemia-homocitrullinuria syndrome. Orphanet J Rare Dis 10:29

    Article  PubMed  PubMed Central  Google Scholar 

  • McHugh D, Cameron CA, Abdenur JE et al (2011) Clinical validation of cutoff target ranges in newborn screening of metabolic disorders by tandem mass spectrometry: a worldwide collaborative project. Genet Med 13:230–254

    Article  PubMed  Google Scholar 

  • Morioka D, Kasahara M, Takada Y et al (2005) Current role of liver transplantation for the treatment of urea cycle disorders: a review of the worldwide English literature and 13 cases at Kyoto University. Liver Transpl 11:1332–1342

    Article  PubMed  Google Scholar 

  • Msall M, Batshaw ML, Suss R, Brusilow SW, Mellits ED (1984) Neurologic outcome in children with inborn errors of urea synthesis. Outcome of urea-cycle enzymopathies. N Engl J Med 310:1500–1505

    Article  CAS  PubMed  Google Scholar 

  • Nagata N, Matsuda I, Matsuura T et al (1991) Retrospective survey of urea cycle disorders. Part 2. Neurological outcome in forty-nine Japanese patients with urea cycle enzymopathies. Am J Med Genet 40:477–481

    Article  CAS  PubMed  Google Scholar 

  • Nassogne MC, Héron B, Touati G, Rabier D, Saudubray JM (2005) Urea cycle defects: management and outcome. J Inherit Metab Dis 28:407–414

    Article  CAS  PubMed  Google Scholar 

  • Picca S, Dionisi-Vici C, Bartuli A et al (2015) Short-term survival of hyperammonemic neonates treated with dialysis. Pediatr Nephrol 30:839–847

    Article  PubMed  Google Scholar 

  • Richter SJ, McCann MH (2007) Multiple comparison of medians using permutation tests. J Mod Appl Stat Methods 6(2):399–412

    Article  Google Scholar 

  • Rüegger CM, Lindner M, Ballhausen D et al (2014) Cross-sectional observational study of 208 patients with non-classical urea cycle disorders. J Inherit Metab Dis 37:21–30

    Article  PubMed  Google Scholar 

  • Schaefer F, Straube E, Oh J, Mehls O, Mayatepek E (1999) Dialysis in neonates with inborn errors of metabolism. Nephrol Dial Transplant 14:910–918

    Article  CAS  PubMed  Google Scholar 

  • Schubiger G, Bachmann C, Barben P et al (1991) N-acetylglutamate synthetase deficiency: diagnosis, management and follow-up of a rare disorder of ammonia detoxication. Eur J Pediatr 150:353–356

    Article  CAS  PubMed  Google Scholar 

  • Smucker MD, Allan J, Carterette B (2007) A comparison of statistical significance tests for information retrieval evaluation. CIKM’07 Proceedings of the sixteenth ACM conference on information and knowledge management, 623-632

  • Summar ML, Dobbelaere D, Brusilow S, Lee B (2008) Diagnosis, symptoms, frequency and mortality of 260 patients with urea cycle disorders from a 21-year, multicenter study of acute hyperammaemic episodes. Acta Paediatr 97:1420–1425

    Article  PubMed  PubMed Central  Google Scholar 

  • Summar ML, Koelker S, Freedenberg D et al (2013) The incidence of urea cycle disorders. Mol Genet Metab 110:179–180

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Uchino T, Endo F, Matsuda I (1998) Neurodevelopmental outcome of long-term therapy of urea cycle disorders in Japan. J Inherit Metab Dis 21(Suppl 1):151–159

    Article  PubMed  Google Scholar 

  • World Health Organization, Food and Agriculture Organization of the United Nations, United Nations University (2007) Protein and amino acid requirements in human nutrition. Report of a joint WHO/FAO/UNU expert consultation. WHO Press, Geneva, WHO Technical Report Series, No. 935

    Google Scholar 

Download references

Acknowledgments

We are indebted to all patients and their families who have been willing to contribute to this study, to share their experience on living with a rare disease, and for their trust. We are grateful for fruitful collaboration with the following clinical partners, patient support groups and industrial partners (in alphabetical order of countries): Lut de Baere, Nathalie Stroobant (Belgische Organisatie voor Kinderen en Volwassenen met een Stofwisselingsziekte VZW [BOKS], Belgium), Nela Carić (Hrvatska udruga za rijetke bolesti, Croatia), Veronika Dvorakova (Charles University and General University of Prague, First Faculty of Medicine, Prague, Czech Republic), Annika and Kennet Rovsing (PND – Protein Nedbrydnings Defekt Foreningen, Denmark), Samantha Parker (Orphan Europe SARL, France), EURORDIS, European Organisation for Rare Disease (France), Markus Ott, Beate Szczerbak (Nutricia Metabolics GmbH, Germany), Hubertus von Voss, Raimund Schmid (Kindernetzwerk e.V., Germany), Mandy Kretschmer (Glutarazidurie e.V., Germany), Reinhild Link (Wiesbaden, representing the SSIEM Dieticians Group), Persephone Augoustides-Savvopoulou (University A’Pediatric Department, Metabolic Laboratory, ‘Hippocration’ General Hospital of Thessaloniki), Zarifis Dimitroulis (KRIKOS ZOIS – Society for patients and friends of patients with inherited metabolic diseases), Evridiki Drogari (University of Athens, Aghia Sophia Children's Hospital, Unit of Metabolic Diseases, Athens), Renza Barbon Galluppi (UNIAMO FIMR, Italy), Susan Udina (COMETA ASMME – Associazione Studio Malattie Metaboliche Ereditarie – ONLUS, Italy), Hanka Meutgeert (Volwassenen en Kinderen met Stoffwisselingsziekten [VKS], Netherlands), Vanessa Ferreira (Associação Portuguesa CDG, Portugal), Miguel Macedo (Apofen, Portugal), Sérgio Braz Antão (Rarrisimas, Portugal), Sergi Faber (Catalana de Trastorns Metabòlics Hereditaris, Spain), Sofia Nordin (Svedish Orphan Biovitrium AB [SOBI], Sweden), Steven Hannigan (CLIMB, Children Living with Inherited Metabolic Diseases, National Information Centre for Metabolic Diseases, and EMDA, the European Metabolic Disorders Alliance), and Robin Lachmann (National Hospital for Neurology and Neurosurgery, Charles Dent Metabolic Unit, London, United Kingdom).

This publication arises from the project “European registry and network for intoxication type metabolic diseases” (E-IMD; EAHC no 2010 12 01) which has received funding from the European Union, in the framework of the Health Programme. After the end of the EU funding period the E-IMD patient registry will be sustained by funding from the Kindness-for-Kids Foundation (Munich, Germany) and the Dietmar Hopp Foundation (St. Leon-Rot, Germany). M. Baumgartner and J. Häberle (Zurich, Switzerland) are supported by radiz – Rare Disease Initiative Zurich, a clinical research priority program of the University of Zurich. C. Dionisi-Vici (Rome, Italy) is supported by the association “La vita è un dono”.

Individual contributors (additional co-authors to be listed in the PubMed, in alphabetical order)

Jean-Baptiste Arnoux, Ivo Barić, Eric Bauchart, Matthias R. Baumgartner, Javier Blasco-Alonso, Maria Teresa Cardoso, Brigitte Chabrol, Maja Djordjevic, Francois Eyskens, Peter Freisinger, Florian Gleich, Wanda Gradowska, Stephanie Grünewald, Gisela Haege, Wuh-Liang Hwu, Hariklea Ioannou, Anil Jalan, Daniela Karall, Corinne de Laet, Martin Lindner, Pascale de Lonlay, Diego Martinelli, Linda de Meirleir, Karine Mention, Chris Mühlhausen, Elaine Murphy, Hélène Ogier de Baulny, Carlos Ortez, Luis Peña-Quintana, Victoria Riches, Esmeralda Rodrigues, Etienne Sokal, Nicholas Thompson, Frits A. Wijburg, Monique Williams, and Matthias Zielonka also contributed to this work.

Affiliations of all authors are listed on the first pages.

Author information

Authors and Affiliations

Authors

Consortia

Corresponding author

Correspondence to Roland Posset.

Ethics declarations

All procedures followed were in accordance with the ethical standards of the responsible committee on human studies (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000.

Conflict of Interest

None.

Informed consent

All procedures followed were in accordance with the ethical standards of the responsible committee on human studies (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent was obtained from all patients or their legal guardians prior to study inclusion in countries where this was needed by law.

Animal rights

This article does not contain animal subjects.

Additional information

Communicated by: Bridget Wilcken

Additional individual contributors who should be regarded as co-authors are listed on acknowledgements.

A correction to this article is available online at https://doi.org/10.1007/s10545-017-0117-4.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Table S1

(DOCX 51 kb)

Table S2

(DOCX 52 kb)

Table S3

(DOCX 50 kb)

Table S4

(DOCX 56.0 kb)

Table S5

(DOCX 51 kb)

Table S6

(DOCX 50 kb)

Table S7

(DOCX 49 kb)

Table S8

(DOCX 47 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Posset, R., Garcia-Cazorla, A., Valayannopoulos, V. et al. Age at disease onset and peak ammonium level rather than interventional variables predict the neurological outcome in urea cycle disorders. J Inherit Metab Dis 39, 661–672 (2016). https://doi.org/10.1007/s10545-016-9938-9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10545-016-9938-9

Navigation