Gastric juice levels of lactoferrin and Helicobacter pylori infection.

Background: Recently, in vitro studies suggested that lactoferrin (Lf) might play an important role in the physiopathology of Helicobacter pylori-associated gastritis. However, whether Lf is present in the gastric juice and its relationship with H. pylori infection have not as yet been reported. In the present investigation the presence of Lf in gastric juice and its correlation with H. pylori infection were assessed.

Methods: This study comprised 30 H. pylori-positive and 14-negative patients with chronic gastritis. Gastric juice levels of Lf were measured with enzyme-linked immunoassays. Gastric juice concentration of Lf was also investigated in accordance with the histologic findings of biopsy specimens in the gastric body and antrum.

Results: Lf concentration in gastric juice was significantly higher in H. pylori-positive than in -negative patients (P = 0.033). The pH values are known to influence the levels of Lf. However, intragastric Lf levels were also significantly increased in H. pylori-positive patients as compared with H. pylori-negative patients after correcting the Lf levels for pH values (P = 0.029) or after adjusting the pH values of the gastric juice with NaHCO3 solution in both groups of patients (P = 0.0007). In addition, the gastric juice levels of Lf correlated significantly with the gastric mucosal concentrations of Lf in the gastric body (P < 0.005, r = 0.568) and the antrum (P < 0.05, r = 0.401).

Conclusions: This study showed for the first time that Lf is present in gastric juice and that it correlates with H. pylori infection. Lf may constitute a good marker for H. pylori-associated gastritis. Although correlation does not prove causation, this study suggests that Lf might play an important role in the physiopathology of H. pylori-associated gastritis.