Clinical relevance of virulence genes in Helicobacter pylori isolates recovered from adult dyspeptic patients in Turkey

Purpose: Bacterial virulence factors play a major role in the pathogenesis of Helicobacter pylori infection. The aims of this study were to evaluate virulence genes in H. pylori isolates and to compare the presence of these genes and associated clinical pathologies. Methods: A total of 148 H. pylori isolates, recovered from adult dyspeptic patients, were used. The patients, from whom the isolates were obtained, were assigned to two groups by their endoscopic findings, which manifested as chronic gastritis or peptic ulcer. The presence of gastric atrophy and intestinal metaplasia was recorded for each patient, based on histopathological examination. Analyses of the virulence genes were performed by the polymerase chain reaction technique. Results: The patients had a mean age of 47 ?± ?15 years and 86 (58%) of them were female. Based on endoscopic examination, 103 (69.6%) patients were diagnosed with chronic gastritis and 45 (30.4%) with peptic ulcer. Histopathological examination revealed intestinal metaplasia in 30 (20%) patients and gastric atrophy in 12 (8%) patients. The prevalence rates of cagA, cagE, iceA1, iceA2, and babA2 were determined to be 87%, 74%, 58%, 26%, and 95%, respectively. The most prevalent vacA alleles were s1/s1a (82%/97%) and the least prevalent allele was s2 (20%). A new vacA genotype (s1as1bs1c) was detected, for the first time, in 18 (12%) isolates. No significant difference was found between the patient groups with chronic gastritis and peptic ulcer for the prevalences of the virulence genes (p ?> ?0.05). Furthermore, intestinal metaplasia and gastric atrophy showed no significant correlation with the virulence genes (p ?> ?0.05). Conclusions: It is thoughted that H. pylori isolates with predominant cagA, cagE, VacA (s1, s1a), and babA2 virulence genes are associated with gastroduodenal diseases. However, there is no correlation between gastric premalignant lesions and virulence genes. © 2022 Indian Association of Medical Microbiologist

SAĞLIKLI SIĞIRLARIN DIŞKILARINDAN LİSTERİA SPP. İZOLASYON VE İDENTİFİKASYONU* Isolation and Identification of Listeria Spp. from Faeces Samples of Healty Cattle

In this study, Listeria spp were isolatedand identificated in faecal samples from 100 healthycows in a Private Commercial Dairy ProductsCompany in different periods (January, October,April, July) of the 2003. For the isolation of Listeriaspp., Listeria Selective Broth (Oxoid) and ListeriaSelective Agar (Oxoid) were used on the samples offaeces. Upon the first isolation of the samples, themethod of cold enrichment was used for the sampleson which isolation was not possible. Then theisolation procedure was reapplied to negativesamples after the third and the seventh week. In orderto grow isolates common biochemistry tests wereapplied and API Listeria (Biomerieux, France) TestKit was used. A hundred faeces samples were takenfrom healthy cattle in the months of January, October,April and July. In the first isolation studies carriedout in October, out of 100 faeces, 52 (%52), inJanuary 55 (%55), in April, 31 (%31) and in July 30(%30) were positive for Listeria spp. In the coldenrichment process, no production of Listeria spp wasobserved in the 3&nbsp;rd week. In the seventh week, seven(%14.58) of 48 negative samples in October, six (%13.31) of 45 negative samples in January, seven (%11.59) of 69 samples in April, six (%8.57) of 70negative samples in July were isolated Listeria spp.According to the findings in our research, thespreading, to the nature in the cow faeces of Listeriaspp. which has a wide range of survival temperature,is a potantial danger for the health of humans andanimals.</p

Identification of Campylobacter spp. Isolates with Phenotypic Methods and Multiplex Polymerase Chain Reaction and Their Antibiotic Susceptibilities

The aims of this study were to detect the frequency of isolation of thermophilic Campylobacter spp. from acute gastroenteritis cases by phenotypic and molecular methods and to evaluate the antibiotic susceptibilities of the isolates. A total of 3287 stool samples obtained from diarrheal patients who were admitted to Kayseri Training and Research Hospital, Kayseri, Turkey, between March 2010 - March 2011 and sent to the microbiology laboratory, were included in the study. Cefoperazone, amphotericin B and teicoplanin (CAT) supplemented Campylobacter Blood-free Selective Medium (modified CCDA-Preston, Oxoid CM739, UK) was used for the isolation of Campylobacter spp. The media inoculated with stool samples were incubated at 42 degrees C microaerobically for 72 to 96 hours. The genus and species level identifications of the thermophilic Campylobacter spp. isolates defined by phenotypic tests were carried out with multiplex polymerase chain reaction (mPCR). Antibiotic susceptibilities of the isolates were detected by disc diffusion method and the results were evaluated according to the CLSI guidelines. The thermophilic Campylobacter spp. were isolated from 5.4% (179/3287) of the patients' stool samples. Of Campylobacter positive cases 71% (127/179) were children and 58% (104/179) were male. The prevalence rate was estimated as 7.5% (127/1683) for children and 3.2% (52/1604) for adults. Of the isolates, 146 (82%) were identified as C.jejuni, 24 (13%) were C.coli, 6 (3%) were C.lari and 3 (2%) were C.upsaliensis with phenotypic tests. By using mPCR, 152 (85%) and 27 (15%) of 179 isolates were identified as C.jejuni and C.coli, respectively. Three of the six isolates identified as C.lari by the phenotypic methods were identified as C.jejuni and the remaining three as C.coli by mPCR. Phenotypically identified three C.upsaliensis isolates were shown to be C.jejuni (n=2) and C.coll (n=1). On the other hand one C.coli isolate was found to be C.jejuni by mPCR. The rates of resistance of the isolates were 92.6% for trimethoprim-sulfamethoxazole, 79.5% for nalidixic acid, 75.6% for levofloxacin, 73.9% for ciprofloxacin, 40.3% for ampicillin, 35% for cefotaxime, 33.4% for piperacillin-tazobactam, 24% for tetracycline, 14.6% for clindamycin, 11.2% for amikacin and 6.3% for erythromycin. During the 13 months study period, the highest isolation rates were detected between March-June (mean rate 66%). Our data concerning the prevalence and antibiotic resistance rates revealed the significance of campylobacters in gastroenteritis cases. Therefore, specific microbiological isolation and identification methods should be applied in routine microbiology laboratories to investigate the presence of campylobacters in gastroenteritis etiology. Besides, determination of the antibiotic susceptibilities of the isolates on routine basis should be encouraged to help to guide the antimicrobial treatment approaches in case of gastroenteritis. The results of this study also indicated that phenotypic tests were adequate for the identification of campylobacters at the genus-level, however, for accurate identification at the species level and for reliable epidemiological data molecular analysis might be added to the detailed identification procedures