Document Detail

Amino acid challenge in patients with cirrhosis: a model for the assessment of treatments for hepatic encephalopathy.
MedLine Citation:
PMID:  11434611     Owner:  NLM     Status:  MEDLINE    
BACKGROUND/AIMS: To mimic episodic hepatic encephalopathy after gastrointestinal bleeding under controlled conditions, cirrhotic patients were challenged with an amino acid mixture of comparable composition to haemoglobin. METHODS: Basal EEG, psychometric score (HE test), reaction times and venous blood ammonia were recorded. Following a 54 or 108 gm oral amino acid challenge, blood ammonia levels and EEG were recorded at 30-min intervals, and psychometric testing was repeated at 180 min. Ten controls (57 +/- 2) and 31 cirrhotics (52 +/- 2) of which 21 were Child's grade A or B and 10 grade C underwent the challenge. Nine had a transjugular intrahepatic porta-systemic shunt in situ. RESULTS: Seventeen patients had abnormal baseline HE scores. Basal blood ammonia and reaction time A were significantly greater in patients (52 +/- 5 micromol/l and 478 +/- 20 ms, respectively) than controls (19 +/- 2 micromol/l and 372 +/- 14 ms) (P < 0.001). Following the challenge, in patients with advanced liver disease (Child's grade B and C) the slowing of reaction time A (+85 +/- 38 and +71 +/- 31 ms, respectively; P < 0.03) and EEG (ratio of slow to fast wave activity +0.31 +/- 0.12 and +0.58 +/- 0.19; P < 0.02) were significantly greater than in controls (-3.3 +/- 8 ms and 0.00 +/- 0.03, respectively). Patients with an abnormal basal HE score had the most pronounced changes (reaction time A +110 +/- 39 ms, P < 0.01, EEG +0.52 +/- 13, P < 0.01, respectively). The change in EEG ratio correlated with the dose of amino acid administered (r = 0.96; P < 0.008). CONCLUSION: The amino acid challenge constitutes a reproducible human model of episodic, Type C hepatic encephalopathy unaffected by the complications usually encountered in clinical practice.
A Douglass; H Al Mardini; C Record
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of hepatology     Volume:  34     ISSN:  0168-8278     ISO Abbreviation:  J. Hepatol.     Publication Date:  2001 May 
Date Detail:
Created Date:  2001-07-03     Completed Date:  2001-12-05     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  8503886     Medline TA:  J Hepatol     Country:  Denmark    
Other Details:
Languages:  eng     Pagination:  658-64     Citation Subset:  IM    
Department of Medicine, University of Newcastle upon Tyne, UK.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Amino Acids* / administration & dosage,  chemistry
Ammonia / blood
Dose-Response Relationship, Drug
Hemoglobins / chemistry
Hepatic Encephalopathy / blood,  chemically induced*,  etiology*,  psychology
Liver Cirrhosis / complications*
Middle Aged
Portasystemic Shunt, Transjugular Intrahepatic
Reaction Time / drug effects
Reg. No./Substance:
0/Amino Acids; 0/Hemoglobins; 7664-41-7/Ammonia

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Hepatopulmonary syndrome in candidates for liver transplantation.
Next Document:  Sequence of events in the assembly of Mallory body components in mouse liver: clues to the pathogene...