Dietary management of urea cycle disorders: UK practice.

Abstract

BACKGROUND:

There is no published data describing UK dietary management of urea cycle disorders (UCD). The present study describes dietary practices in UK inherited metabolic disorder (IMD) centres.

METHODS:

Cross-sectional data from 16 IMD centres were collected by a questionnaire describing the management of UCD patients on prescribed protein-restricted diets.

RESULTS:

One hundred and seventy-five patients [N-acetylglutamate synthase deficiency, n = 3; carbamoyl phosphate synthase deficiency (CPS), n = 8; ornithine transcarbamoylase deficiency (OTC), n = 75; citrullinaemia, n = 41; argininosuccinic aciduria (ASA), n = 36; arginase deficiency, n = 12] were reported; 70% (n = 123) aged 0-16 years; 30% (n = 52) >16 years. Prescribed median protein intake decreased with age (0-6 months: 2 g kg(-1) day(-1); 7-12 months: 1.6 g kg(-1) day(-1); 1-10 years: 1.3 g kg(-1) day(-1); 11-16 years: 0.9 g kg(-1) day(-1) and >16 years: 0.8 g kg(-1) day(-1)) with little variation between disorders. Adult protein prescription ranged 0.4-1.2 g kg(-1) day(-1) (40-60 g day(-1)). In the previous 2 years, 30% (n = 53) were given essential amino acid supplements (EAAs) (CPS, n = 2; OTC, n = 20; citrullinaemia, n = 15; ASA, n = 7; arginase deficiency, n = 9). EAAs were prescribed for low plasma quantitative essential amino acids (n = 13 centres); inadequate natural protein intake (n = 11) and poor metabolic control (n = 9). From diagnosis, one centre prescribed EAAs for all patients and one centre for severe defects only. Only 3% (n = 6) were given branch chain amino acid supplements. Enteral feeding tubes were used by 25% (n = 44) for feeds and 3% (n = 6) for medications. Oral energy supplements were prescribed in 17% (n = 30) of cases.

CONCLUSIONS:

In the UK, protein restriction based on World Health Organization 'safe intakes of protein', is the principle dietary treatment for UCD. EAA supplements are prescribed mainly on clinical need. Multicentre collaborative research is required to define optimal dietary treatments.

• Authors: S Adam, H Champion, A Daly, S Dawson, M Dixon, C Dunlop, J Eardley, S Evans, C Ferguson, C Jankowski, S Lowry, A MacDonald, C Maritz, A Micciche, L Robertson, J Stafford, A Terry, R Thom, K van Wyk, D Webster, F J White, J Wildgoose, British Inherited Metabolic Diseases Group (BIMDG) Dietitian’s Group
• Journal: Journal of human nutrition and dietetics : the official journal of the British Dietetic Association (J Hum Nutr Diet) Vol. 25 Issue 4 Pg. 398-404 (Aug 2012) ISSN: 1365-277X [Electronic] England
• PMID: 22594780 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2012 The Authors. Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

Chemical References

• Amino Acids, Branched-Chain
• Amino Acids, Essential
• Dietary Proteins

Topics

• Adolescent
• Adult
• Amino Acids, Branched-Chain (administration & dosage)
• Amino Acids, Essential (administration & dosage)
• Child
• Child, Preschool
• Cross-Sectional Studies
• Dietary Proteins (administration & dosage)
• Dietary Supplements
• Dietetics
• Enteral Nutrition
• Humans
• Infant
• Infant, Newborn
• Nutritional Support (methods)
• Surveys and Questionnaires
• United Kingdom
• Urea Cycle Disorders, Inborn (diet therapy)