Association between vitamin B12 level and anti-parietal cells and anti-intrinsic factor antibodies among adult Jordanian patients with Helicobacter pylori infection

OBJECTIVE: Evaluate the association of Helicobacter pylori infection with anti-parietal cell antibodies (APCA) and anti-intrinsic factor antibodies (AIFA) and their impact on vitamin B12 serum level. PATIENTS AND METHODS: One hundred patients (M/F: 43/57; age 46.5 ± 17.5 years) who underwent upper gastrointestinal endoscopy at King Abdullah University Hospital, Irbid, Jordan were enrolled in the study. The patients were grouped as H. pylori-infected (n = 81) or H. pylori negative (n = 19) by histopathological examination. Fasting serum vitamin B12 levels, antiparietal cell antibodies and anti-intrinsic factor antibodies for patients and controls were determined. RESULTS: Anti-parietal cell antibodies and anti-intrinsic factor antibodies were positive in 9.9% and 18.5% of H. pylori-positive patients respectively. None of the H. pylori negative subjects had anti-parietal cell antibodies or anti-intrinsic factor antibodies. Serum vitamin B12 level was lower in the H. pylori-infected patients (275 ± 70.4 pg/mL) than in controls (322.9 ± 60.7 pg/mL; p 0.05). H. pylori was positive in 94% of the low-vitamin B12 group compared with 64.6% of the normal-vitamin B12 group (p 0.5). CONCLUSION: Patients with H. pylori infection are more likely to have anti-parietal cell antibodies and anti-intrinsic factor antibodies. There was an association between H. pylori infection and lower vitamin B12 levels. H. pylori infection might be a significant factor in the pathogenesis of autoimmune gastritis.

Giardia lamblia trophozoites in gastric biopsies.

To assess the prevalence of gastric giardiasis in gastric biopsies of patients with carcinoma stomach and in patients taking treatment for duodenal ulcer. Gastric biopsy specimens from 54 patients of carcinoma stomach and 100 antral biopsies from patients taking treatment for duodenal ulcer were included in the study. Sections were stained with haematoxylin and eosin, methylene blue and May Grunwald-Giemsa stains and examined for presence of Giardia lamblia trophozoites. Eight out of 54 (14.9%) biopsies of gastric carcinoma patients harboured trophozoites of Giardia lamblia. Associated H. pylori infection was present in all biopsies (8/8; 100%). Atrophy and intestinal metaplasia was present in 62.5% (5/8) and 25% (2/8) cases respectively. Sections from seven out of 35 patients (20%) taking treatment for duodenal ulcer showed presence of G. lamblia. H. pylori infection, gastritis and atrophy were found in 85.7% (6/7), 71.4% (5/7) and 28.6% (2/7) cases respectively. First gastric biopsy in these patients was negative for G. lamblia but 2nd and 3rd biopsies were positive. A careful search for G. lamblia trophozoites should be made while examining the gastric biopsies, especially in patients with carcinoma stomach, intestinal metaplasia, atrophic gastritis and those taking treatment for duodenal ulcer. This may help in indirect diagnosis of clinically unsuspected cases of intestinal giardiasis and may explain persistence of vague upper gastrointestinal tract (UGIT) symptoms despite clearance of H. pylori in patients on anti-ulcer therapy.