The Association Between Helicobacter pylori Infection and Nonalcoholic Fatty Liver Disease.
OBJECTIVE
Helicobacter pylori (HP) infection is known to be a significant risk factor in the development of certain gastric conditions, such as ulcers, gastritis, and malignancy. Recently, however, the systemic effect of HP infection on other organ systems has come to be appreciated. In this review, we will explore the association between HP infection and nonalcoholic fatty liver disease (NAFLD), the hepatic component of metabolic syndrome.


RESULTS
The possible association between HP infection and NAFLD initially stemmed from the isolation of HP bacteria in the livers of patients with NAFLD. Although there have been conflicting results, several subsequent clinical trials have demonstrated a higher rate of fatty liver and NASH in HP-positive patients compared to HP-negative patients; in addition, small trials examining the effect of HP eradication have shown improvement in markers of NAFLD activity, further supporting a link between these two conditions. The pathophysiology behind the possible association between HP infection and NAFLD has yet to be fully elucidated; several possible mechanisms include induction of a pro-inflammatory state that shifts the body toward a more lipogenic profile, and a hormonal shift that favors progression toward insulin resistance and fibrosis. The association between HP infection and NAFLD has been demonstrated in several clinical trials, including small trials evaluating the effect of HP eradication on NAFLD. Future studies examining the pathophysiology behind this association are the next step in characterizing the relationship between these two conditions.
Division of Gastroenterology, Southern California Permanente Medical Group, Kaiser Permanente, Orange County, Anaheim, CA, USA.
Derek M
DM
Tang
Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Drive, Building 10, Room 9C-101, Bethesda, MD, 20892, USA. sheila.kumar@nih.gov.
Sheila
S
Kumar
D016481:Helicobacter Infections / Q000150:complications* / Q000503:physiopathology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D065626:Non-alcoholic Fatty Liver Disease / Q000382:microbiology* / Q000503:physiopathology
Helicobacter pylori; Nonalcoholic fatty liver disease; Nonalcoholic steatohepatitis