Clinical relevance of cagL gene and virulence genotypes with disease outcomes in a Helicobacter pylori infected population from Iran
Helicobacter pylori infection is common in Iran as in other developing countries. Certain genotypes of H. pylori have been associated with increased occurrence of chronic gastritis, peptic ulcers, and gastric adenocarcinoma. The aim of this study was to investigate the clinical relevance of cagL gene and other virulence genotypes of H. pylori isolates with clinical outcomes in Iranian patients. Totally, 126 symptomatic patients who underwent gastroduodenal endoscopy were enrolled in the study. Sixty-one H. pylori strains were isolated from the patients studied. The presence of the cagL, cagA, vacA, iceA, babA2 and sabA genes in the corresponding H. pylori isolates were determined by polymerase chain reaction and the results were compared with clinical outcomes and histopathology. The cagL, cagA, vacA s1, vacA s2, vacA m1, vacA m2, iceA1, iceA2, babA 2 , and sabA genotypes were detected in 96.7, 85.2, 75.4, 24.6, 29.5, 70.5, 42.6, 23, 96.7, and 83.6 % of the isolates, respectively. The three genotypic combinations, cagL/cagA/vacAs1m1/iceA1/babA2/sabA, cagL/cagA/vacAs1m2/iceA1/babA2/sabA, and cagL/cagA/vacAs1m2/iceA2/babA2/sabA were determined as the most prevalent combined genotypes. There was a significant correlation between the presence of cagL gene and cagA positivity (P = 0.02). No significant correlation was found between the various genotypes and clinical outcomes (P > 0.05). The present study showed a very high prevalence of cagL genotype among the H. pylori isolates from Iranian patients. Our results demonstrated that neither single genotype nor combination genotypes of virulence-associated genes was significantly helpful markers for predicting the severity of gastroduodenal disease associated with H. pylori infection in Iranian patients.
KeywordsHelicobacter pylori cagL Virulence genotypes Clinical outcomes Iranian patients
The authors are thankful to Dr. Mahsa Molaei from the Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences. This study was funded by a research grant from the Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. The project was also partially supported by a PhD grant from the Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Conflict of interest
The authors have no conflict of interest to declare.
- Arents NL, van-Zwet AA, Thijs JC, Kooistra-Smid AM, Van Slochteren KR, Degener JE, Kleibeuker JH, Van Doorn LJ (2001) The importance of vacA, cagA, and iceA genotypes of Helicobacter pylori infection in peptic ulcer disease and gastroesophageal reflux disease. Am J Gastroenterol 96:2603–2608CrossRefGoogle Scholar
- Blaser MJ, Perez-Perez GI, Kleanthous H, Cover TL, Peek RM, Chyou PH, Stemmermann GN, Nomura A (1995) Infection with Helicobacter pylori strains possessing cagA is associated with an increased risk of developing adenocarcinoma of the stomach. Cancer Res 55:2111–2115Google Scholar
- Figueiredo C, Machado JC, Pharoah P, Seruca R, Sousa S, Carvalho R, Capelinha AF, Quint W, Caldas C, van Doorn LJ, Carneiro F, Sobrinho-Simões M (2002) Helicobacter pylori and interleukin 1 genotyping: an opportunity to identify high-risk individuals for gastric carcinoma. J Natl Cancer Inst 94:1680–1687CrossRefGoogle Scholar
- Hosseini E, Poursina F, de Wiele TV, Safaei HG, Adibi P (2012) Helicobacter pylori in Iran: a systematic review on the association of genotypes and gastroduodenal diseases. J Res Med Sci 17:280–292Google Scholar
- Hussein NR, Mohammadi M, Talebkhan Y, Doraghi M, Letley DP, Muhammad MK, Argent RH, Atherton JC (2008) Differences in virulence markers between Helicobacter pylori strains from Iraq and those from Iran: potential importance of regional differences in H. pylori-associated disease. J Clin Microbiol 46:1774–1779CrossRefGoogle Scholar
- Lage AP, Godfroid E, Fauconnier A, Burette A, Butzler JP, Bollen A, Glupczynski Y (1995) Diagnosis of Helicobacter pylori infection by PCR: comparison with other invasive techniques and detection of cagA gene in gastric biopsy specimens. J Clin Microbiol 33:2752–2756Google Scholar
- Lehours P, Ménard A, Dupouy S, Bergey B, Richy F, Zerbib F, Ruskoné-Fourmestraux A, Delchier JC, Mégraud F (2004) Evaluation of the association of nine Helicobacter pylori virulence factors with strains involved in low-grade gastric mucosa-associated lymphoid tissue lymphoma. Infect Immun 72:880–888CrossRefGoogle Scholar
- Mahdavi J, Sondén B, Hurtig M, Olfat FO, Forsberg L, Roche N, Angstrom J, Larsson T, Teneberg S, Karlsson KA, Altraja S, Wadström T, Kersulyte D, Berg DE, Dubois A, Petersson C, Magnusson KE, Norberg T, Lindh F, Lundskog BB, Arnqvist A, Hammarström L, Borén T (2002) Helicobacter pylori SabA adhesin in persistent infection and chronic inflammation. Science 297:573–578CrossRefGoogle Scholar
- Mukhopadhyay AK, Kersulyte D, Jeong JY, Datta S, Ito Y, Chowdhury A, Chowdhury S, Santra A, Bhattacharya SK, Azuma T, Nair GB, Berg DE (2000) Distinctiveness of genotypes of Helicobacter pylori in Calcutta, India. J Bacteriol 182:2327–3219Google Scholar
- Stolte M, Meining A (2001) The updated Sydney system: classification and grading of gastritis as the basis of diagnosis and treatment. Can J Gastroenterol 15:591–598Google Scholar
- Vaziri F, Najar Peerayeh S, Alebouyeh M, Mirzaei T, Yamaoka Y, Molaei M, Maghsoudi N, Zali MR (2013) Diversity of Helicobacter pylori genotypes in Iranian patients with different gastroduodenal disorders. World J Gastroenterol 19:5685–5692Google Scholar
- Yamaoka Y, Kodama T, Gutierrez O, Kim JG, Kashima K, Graham DY (1999) Relationship between Helicobacter pylori iceA, cagA, and vacA status and clinical outcome: studies in four different countries. J Clin Microbiol 37:2274–2279Google Scholar