Yonsei Med J.  2013 Jul;54(4):832-838. 10.3349/ymj.2013.54.4.832.

Association of Helicobacter pylori with Elevated Blood Ammonia Levels in Cirrhotic Patients: A Meta-Analysis

• Jiang HX
• Qin SY
• Min ZG
• Xie MZ
• Lin T
• Hu BL
• Guo XY

• KMID: 2158215
• DOI: http://doi.org/10.3349/ymj.2013.54.4.832

Abstract

PURPOSE
The association between Helicobacter pylori (H. pylori) and blood ammonia levels in cirrhotic patients is controversial. We aimed to clarify this controvercy by performing a meta-analysis of published studies.
MATERIALS AND METHODS
We searched PubMed, EMBASE and Cochrane library for studies which explored the association between H. pylori and blood ammonia levels in cirrhotic patients before May 2012. Six cohort studies involved in 632 H. pylori positive and 396 H. pylori negative cirrhotic patients were eligible for our analysis. The summary estimates were presented as standard means differences (SMD) and 95% confidence intervals (CI) from individual studies.
RESULTS
Overall, there was significant association between H. pylori infection and the elevated blood ammonia levels in cirrhotic patients (SMD=0.34, 95% CI=0.21-0.47, I2=42.1%). Sensitivity analysis further confirmed this association. Subgroup analysis showed that the association was found only in Asian ethnicity, but not in Caucasian ethnicity.
CONCLUSION
H. pylori infection is associated with elevated blood ammonia levels in cirrhotic patients, and more large scale studies and stratify analysis are warranted in order to further evaluate this association.

Keyword

Helicobacter pylori; blood; ammonia; meta-analysis

MeSH Terms

Ammonia/blood
Asian Continental Ancestry Group
European Continental Ancestry Group
Helicobacter Infections/*blood
Helicobacter pylori/pathogenicity
Humans
Liver Cirrhosis/*blood/*microbiology
Publication Bias
Regression Analysis
Ammonia

Figure

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  Fig. 1 Flow diagram of the study selection process.

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  Fig. 2 Meta-analysis of nine included studies. SMD, standard means differences; CI, confidence intervals.

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  Fig. 3 Funnel Plot of the Meta-Analysis (Begg's test). SMD, standard means differences.

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