ABH and Lewis antigen distributions in blood, saliva and gastric mucosa and H pylori infection in gastric ulcer patients.

AIM: To investigate the ABH and Lewis antigen expression in erythrocytes, saliva and gastric epithelium, as well as the association between H pylori and the presence of gastric epithelial lesions. METHODS: The distribution of ABH and Lewis blood group antigens in erythrocytes, saliva and gastric mucosa of H pylori-infected gastric ulcer patients was analyzed. Forty-two patients with gastric ulcer were studied, and fifty healthy individuals were used as control group. The blood group antigens were determined by direct hemagglutination, dot-ELISA and immunohistochemical methods in erythrocytes, saliva and gastric mucosa specimens, respectively. Diagnosis for H pylori infection was performed by conventional optical microscopy and ELISA. RESULTS: A higher seroprevalence of IgG H pylori specific antibodies was observed in gastric ulcer patients (90%) compared to the control group (60%). We observed a significant increase of phenotypes O, A2 and Lewis b in H pylori-infected patients. The expression of these antigens had progressive alterations in areas of ulcerous lesions and intestinal metaplasia. CONCLUSION: ABH and Lewis blood group antigens are a good indicator for cellular alterations in the gastric epithelium.

[Seroprevalence of antibodies against Helicobacter pylori CagA antigen in patients with gastric ulcer in the North region of Brazil]. / Soroprevalência de anticorpos contra o antígeno CagA do Helicobacter pylori em pacientes com úlcera gástrica na região Norte do Brasil.

Helicobacter pylori is a pathogenic agent with a worldwide distribution and is involved in the development of many gastrointestinal diseases. Nowadays infection with the virulent strain CagA+ of H. pylori is considered one of the main etiological factors in the development of gastric ulcer. Based on this information, we investigated the seroprevalence of virulent strains among patients with gastric ulcer from one region, using serologic tests to detect antibodies against H. pylori and CagA protein. Infection by the virulent strain was found in 82% (40/55) of the patients, and among these, 89% (40/45) presented an increased degree of inflammation in the gastric mucosa, with a dense infiltration of leukocytes in the tissue, which probably favored the formation of gastric ulcer. We concluded that the presence of the virulent strain is related to the development of an increased inflammation in the gastric mucosa.

Soroprevalência de anticorpos contra o antígeno CagA do Helicobacter pylori em pacientes com úlcera gástrica na regiÒo Norte do Brasil / Seroprevalence of antibodies against Helicobacter pylori CagA antigen in patients with gastric ulcer in the North region of Brazil

Helicobacter pylori is a pathogenic agent with a worldwide distribution and is involved in the development of many gastrointestinal diseases. Nowadays infection with the virulent strain CagA+ of H. pylori is considered one of the main etiological factors in the development of gastric ulcer. Based on this information, we investigated the seroprevalence of virulent strains among patients with gastric ulcer from one region, using serologic tests to detect antibodies against H. pylori and CagA protein. Infection by the virulent strain was found in 82 (40/55) of the patients, and among these, 89 (40/45) presented an increased degree of inflammation in the gastric mucosa, with a dense infiltration of leukocytes in the tissue, which probably favored the formation of gastric ulcer. We concluded that the presence of the virulent strain is related to the development of an increased inflammation in the gastric mucosa.