Presence of Helicobacter Species in Gastric Mucosa of Human Patients and Outcome of Helicobacter Eradication Treatment

Abstract

The genus Helicobacter is composed of bacteria that colonize both the human and animal gastrointestinal tract. Helicobacter pylori infects half of the world’s population, causing various disorders, such as gastritis, duodenitis and gastric cancer. Additionally, non-Helicobacter pylori Helicobacter species (NHPH) are commonly found in the stomach of pigs, dogs and cats. Most of these species have zoonotic potential and prevalence rates of 0.2–6.0%, and have been described in human patients suffering from gastric disorders undergoing a gastric biopsy. The aim of this study was to determine the occurrence of Helicobacter spp. in the stomach of patients with gastric cancer (n = 17) and obese (n = 63) patients. Furthermore, the outcome of the Helicobacter eradication treatment and the current infection status was evaluated. Overall, based on the genus-specific PCR followed by sequencing, DNA from Helicobacter spp. was detected in 46.3% of the patients, including single infections with H. pylori in 43.8% of the patients and mixed infections with H. pylori and canine- or feline-associated H. felis in 2.5%. About 32.5% of the patients had been subjected to previous Helicobacter eradication therapy and the triple standard therapy was the most frequent scheme (42.3%). In 48.0% of the patients who received eradication treatment, bacteria were still detected, including one mixed infection. In 23.1% of the patients who reported that a subsequent test had been performed to confirm the elimination of the bacteria, Helicobacter were still detected. In conclusion, although in a smaller percentage, NHPH may also be present in the human stomach. Thus, specific NHPH screening should be included in the diagnostic routine. The continued presence of H. pylori in the stomach of patients recently subjected to eradication schemes raises questions about the efficacy of the current Helicobacter treatments.

Molecular detection of Helicobacter spp. and Fusobacterium gastrosuis in pigs and wild boars and its association with gastric histopathological alterations

“…Two PCR assays were used for detection of H. pylori DNA, one targeting the ureAB gene and the other one targeting the glmM gene. Although a number of studies have been published diagnosing H. pylori infection based on a ureAB gene PCR only [ 19 , 37 , 38 ], some reports indeed claim that H. pylori identification should include these two different target genes amplification [ 39 – 41 ]. Lu et al compared five PCR methods for detection of H. pylori DNA of 24 culture-positive samples obtained from 50 human gastric samples, including PCRs targeting the ureA and glmM gene.…”

Management of Extranodal Marginal Zone Lymphoma: Present and Upcoming Perspectives

“…For example, Helicobacter heilmannii s.s has been found in patients with H. pylori -negative MALT lymphoma, and in animal models, it has also been shown to cause MALT lymphoma [ 23 , 24 ]. Other species with the potential to trigger MALT lymphoma are Helicobacter suis , Helicobacter felis , Helicobacter suis , Helicobacter bizzozeronii and Helicobacter salomnois [ 25 , 26 , 27 , 28 , 29 ]. Interestingly, H. pylori infection has been shown to activate the p38 MAPK pathway, upregulating PD-1 expression by gastric epithelial cells and reducing immune response [ 30 ].…”

Development of serological assays to identifyHelicobacter suisandHelicobacter pyloriinfections

“…Motos et al have proposed that because NHPH may be present in the human stomach, even if only in very small amounts, a specific NHPH screening should be included in the diagnostic routine. 47 Clearly, a large-scale epidemiological investigation of NHPH infection is urgently needed so that clinical practice guidelines can be established for the treatment of NHPH infection.…”

“…infection has yet been identified in the stomachs of cats and dogs [5][6][7]26,27 . Although H. suis colonizes the hog stomach and is the source of zoonotic infection in a high percentage of human cases of H. suis infection [28][29][30] , the infection rate among hog farmers is not higher than that of individuals with no contact with animals 31,32 . It has been hypothesized that H. suis infects humans via the consumption of contaminated pork 33,34 .…”