Lack of Reinfection after Helicobacter Pylori Eradication in Duodenal Ulcer Disease: A Prospective Study from Turin, Italy

Abstract

Turin, Italy. 1999; 19(4): 376-377 Helicobacter pylori (H. pylori) infection plays an important role in the cause of duodenal ulcer (DU). Successful cure of the infection modifies the natural history of the disease, leading to a dramatic reduction of recurrence. 1 In the event of a recurrence, DU can be due to reinfection or recrudescence by H. pylori, therapy with nonsteroidal anti-inflammatory drugs (NSAIDs), or rare and less clear pathogenetic mechanisms. Differences in H. pylori reinfection rates have been reported in several studies, 2-4 and a comparison of strains obtained prior to and after therapy by fingerprint analysis was rarely possible. Therefore, it remains speculative whether true reinfection occurred, or whether it was simply a recrudescence of the previous bacterial infection. 5 The objective of our study was to assess the incidence of reinfection and new ulceration events after demonstrated Helicobacter pylori eradication, in a cohort of patients with recurrent duodenal ulcers. Materials and MethodsWe followed up the natural history of duodenal ulcer disease in 115 patients (83 males, mean age 54.8 years). All of them had a previous diagnosis of recurrent duodenal ulcer documented by endoscopy, and associated H. pylori infection as shown by histology and serology.The starting point of the study was considered the confirmed eradication of the bacterium and DU absence at three months after the end of antibiotic treatment. Each patient underwent the monitoring scheme at 6, 12 and 24 months after the starting point.The presence of Helicobacter pylori infection was judged: 1) by histology (Giemsa staining) on biopsies obtained during endoscopy from the antrum and the fundus; and 2) by measuring specific IgG antibodies against H. pylori by a commercial enzyme-linked immunosorbent assay (ELISA).The infection was considered eradicated when: 1) histology did not demonstrate the bacterium either in the antrum or in the fundus; and 2) the level of circulating anti-Helicobacter pylori antibodies decreased in titer by at least 50% of the initial value. The patients whose levels of specific antibodies did not decrease were offered, independent of the histologic result, a 13 C urea breath test ( 13 C-UBT), using the European Standard Protocol. 6The 13 C-UBT was administered to every patient in case of an ulcer recurrence. We defined reinfection, the positivity for H. pylori infection, as a significant increase of specific IgG antibodies, confirmed by evidence on histology and/or positivity on 13 C-UBT at 12 or 24 months after a demonstrated eradication at six months. Patients were excluded from the study if they were on ulcerogenic drugs, or were taking long-term maintenance antisecretory therapy with proton pump inhibitors or H 2 -receptor blocker drugs. ResultsSeven of the initial 115 patients were lost to follow-up. None of the 108 patients followed up during the average period of 24 months (range 20-27) had a reinfection. Five patients (4.6%) had a duodenal ulcer recurrence, and their mean age was 57...

Management of Helicobacter pylori in Piedmont, Italy

“…82 These findings provided further evidence that the cure of H. pylori infection allows for a dramatic reduction in the frequency of DU recurrences, and that the reinfection in adults is unlikely in their population. The different results of these two studies 81,82 could be explained by the potential relapse risk in the former and the exclusion of reinfection in the latter. The robustness of the second is witnessed by the fact that reinfection should be confirmed by the positivity of at least two tests.…”