Department: Applied Microbiology And Brewing
Helicobacter pylori (H. pylori) is a major cause of antral gastritis, duodenal ulcer disease, gastric ulcers and gastric carcinoma. The aim of these studies were to compare the sensitivities and specificities of various diagnostic tests used in the detection of H. pylori infection and to investigate the effects of using probiotic in the treatment of mice infected with H. pylori. Studies on diagnostic methods, treatment and prevention of Helicobacter pylori infection using probiotics were done in phases which included: the isolation of H. pylori, the infection of mice with the isolate, and the treatment of the mice with a strain of Lactobacillus acidophilus probiotic isolated from the feaces of human. Serum and stool samples from 200 patients (100 males and 100 females) between the ages of 18 and 75 years and enrolled in the gastroenterology unit of Federal Teaching Hospital Abakaliki were tested for H. pylori infection using serum antibody test, stool antigen test, and fecal occult blood test. Stool samples from 71 patients who were positive for H. pylori stool antigen test were cultured. Also, biopsies from 5 dyspeptic patients from Niger Foundation Enugu, were cultured. One hundred and twenty six wistar mice were divided into groups A (negative control), B (positive control) and C (test). The mice in group B and C were inoculated intragastrically with 1 ml suspension of fresh H. pylori in brain heart infusion broth. Group A was inoculated with 1 ml of brain heart infusion broth. Treatment of the mice in group C with a strain of Lactobacillus acidophilus was initiated 1 week post challenge. Six mice from each group were sacrificed for histopathological studies at 10, 14, 21, 28, 35 and 60 days post inoculation. Data were analyzed using SPSS version 20.0. Significant value was taken at p< 0.05. Out of the 200 patients tested, 57 (28.5%) were positive for H. pylori blood antibody test, 71 (35.5%) were positive for H. pylori stool antigen test while 40 (20.0%) were positive for the fecal occult blood test. The result was not statistically significant (p>0.05). Helicobacter pylori was not isolated from the stool samples of the 71 patients who were positive for H. pylori stool antigen test, but was isolated from 1 of the 5 gastric biopsies cultured. Furthermore, the results of the mice in group A showed normal gastric and duodenal epithelium through day 10 to 60, while there were marked changes like dysplasia, necrosis and thinning of the epithelium in group B. With probiotic treatment, the group C mice showed complete regeneration at day 28. However, there was a reversal back to necrotic form at day 35 to 60 showing that the treatment was no longer effective. The result of this study showed that gastric biopsy culture was more reliable than stool culture in the isolation of Helicobacter pylori. The antigen test was more sensitive than the antibody test. Also, the probiotic Lactobacillus acidophilus effectively treated and prevented Helicobacter pylori infection but the beneficial effect terminated after the 28th day. This explains the importance of the duration of treatment using probiotic and the need to add another anti-Helicobacter pylori agent as a synergy or give booster doses of probiotic. Probiotic should be used as a complement in medical practice rather than as an alternative.