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Review
. 2014 Mar 13;2(1):22.
doi: 10.1186/2052-0492-2-22. eCollection 2014.

Hyperammonemia due to urea cycle disorders: a potentially fatal condition in the intensive care setting

Marcel Cerqueira Cesar Machado  1 , Fabiano Pinheiro da Silva  1
Affiliations
Review

Hyperammonemia due to urea cycle disorders: a potentially fatal condition in the intensive care setting

Marcel Cerqueira Cesar Machado et al. J Intensive Care. .

Abstract

Disorders of the urea cycle are secondary to a defect in the system that converts ammonia into urea, resulting in accumulation of ammonia and other products. This results in encephalopathy, coma, and death if not recognized and treated rapidly. Late-onset urea cycle disorders may be precipitated by acute disease and can be difficult to recognize because patients are already ill. Diagnosis of urea cycle disorders is based on clinical suspicion and determination of blood ammonia in suspected patients with neurological symptoms in the intensive care setting. Treatment is based on the removal of ammonia by dialysis or hemofiltration, reduction of the catabolic state, abolishment of nitrogen administration, and use of pharmacological nitrogen scavenging agents.

Keywords: Hyperammonemia; Intensive care unit; Neurological disorders.

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Figures

Figure 1
Figure 1
The urea cycle. CPS-1 cabamoyl phosphate synthetase 1, OTC ornithine transcarbamylase, ASS argininosuccinic acid synthetase, ASL argininosuccinic acid lyase, ARG arginase.
See this image and copyright information in PMC

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