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Abstract in developing world, where infection may appear early in life in childhood, and may arise to an incidence of 80% among young adults. In developed countries, childhood infection is uncommon, but prevalence arise after the age of 40. It was suggested that the eradication of H.pylori does play an important role in the reduction of non ulcer dyspepsia symptoms in the long term, and that the persistence of infection with H.pylori results in more dyspeptic symptoms. It was now recognized that H.pylori infection can cause acute gastritis. Studies from many regions of the world have confirmed the association of H.pylori infection with chronic antral gastritis; H.pylori infection specifically associated with type B gastritis. H.pylori cause chronic inflammation, gastritis which does not generally resolve until the bacterium is eradicated by antimicrobial treatment. It is now well established that H.pylori is associated with more than 90% of duodenal ulcers and 70-80% of gastric ulcers and the cure of this infection results in long term remission. 164 It has been shown that eradiation of H.pylori speeds up gastric ulcer healing with a 6 weeks healing rate of 85%. Recently H.pylori has been designated a class I carcinogen by the world health organization. H.pylori is present up to 92% of patients of gastric MALT lymphoma compared with 50% of control. H.pylori is the major cause of chronic atrophic gastritis and is likely to be an important etiological factor in the development of gastric cancer. The role of H.pylori in the pathogenesis of esophageal reflux has not been elucidated; gastric acid hypersecretion may be implicated and isolation of the organism in patients with reflux- induced gastric metaplasia of the esophagus has been reported in 0-25%of patients. Also GERD may develop de novo or it may be unmasked after successful eradication of H.pylori; on the other hand another study had shown that H.pylori may play a protecting role against GERD.So the role of H.pylori in GERD is still under study to show whether it is positive or negative role. We can say that colorectal carcinoma over express gastrin; and receptors for gastrin (CCKB-R) and (Cox-2), increased plasma level of gastrin should be considered as suitable biomarker of CRC; H.pylori infection may contribute to colonic carcinogenesis by enhancing expression of gastrin and Cox-2, they may account for stimulation of the tumour growth, angiogenesis, and reduction in a apoptosis as evidenced 165 by an increased ratio of mRNA expression for anti-apoptotic Bcl2 over proapoptotic Bax proteins. H.Pylori positive patients who developed CRC should be subjected to H.Pylori eradication; this is expected to reduce hypergastrinemia and to attenuate Cox-2 expression. so treatment of patient with CRC with Cox-2 selective inhibitors now gained a strong support as a preventive measure. However, recent reports have shown that Crohn’s disease patients have lower prevalence of H.pylori infection it was also observed that previous use of sulphasalazine is associated with reduced risk of Helicobacter pylori infection in IBD patients. We can say that the clinical course of Crohn’s disease may be ”sui genesis” connected with H.pylori infection but the exact mechanisms remain to be discovered. H.pylori DNA has been found within the livers of patients with HCC;however culture results have been negative, and a causative association remains unproven. Helicobacter genus bacterium may take part in the pathogenesis of primary biliary cirrhosis and primary sclerosing cholangitis, but its role in the pathogenesis of gallstones is still unknown and needs more clinical trials. Further studies are warranted to illustrate this possibility and whether Helicobacter pylori is involved in the development of malignant liver and biliary tract diseases or not. 166 Among the various tests described for diagnosis of H.pylori, histological examination seems to be the best. It could detect not only the causative agent (H.pylori), but also the disease without significant false positive results. Biopsy is 99% sensitive-99% specific, serology is 95% sensitive-90% specific and ureabreath test is98% sensitive-100% specific. Patient noncompliance and antibiotic resistance are two of the most important reasons for failure of H.pylori therapy. Patient compliance is influenced by a variety of factors including the duration of therapy and severity of treatment associated side effects. There is emerging evidence that sequential therapy may be superior to clarithromycin triple therapy in the eradication of clarithromycin – resistant H.pylori, studies also confirms superiority of 10 days of levofloxacin triple therapy to 7 days of bismuth quadruple therapy. Finally, an effective, safe vaccine that prevents infection with H.pylori would clearly be the optimal intervention strategy in those countries where gastric cancer remains a major problem. Within the next five years, a few vaccines will most likely to be tested in humans. |