Association of inflammation and cytotoxin-associated gene a positive strains of helicobacter pylori in cardiac syndrome x

Inflammatory biomarkers in cardiac syndrome X: a systematic review and meta-analysis

INTRODUCTION

In the current systematic review and meta-analysis, we aim to analyze the existing literature to evaluate the role of inflammatory biomarkers, including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP), tumor necrosis factor-a (TNF-a), and interleukin-6 (IL-6) among individuals with cardiac syndrome X (CSX) compared to healthy controls.

METHODS

We used PubMed, Web of Science, Scopus, Science Direct, and Embase to systematically search relevant publications published before April 2, 2023. We performed the meta-analysis using Stata 11.2 software (Stata Corp, College Station, TX). So, we used standardized mean difference (SMD) with a 95% confidence interval (CI) to compare the biomarker level between patients and healthy controls. The I2 and Cochran's Q tests were adopted to determine the heterogeneity of the included studies.

RESULTS

Overall, 29 articles with 3480 participants (1855 with CSX and 1625 healthy controls) were included in the analysis. There was a significantly higher level of NLR (SMD = 0.85, 95%CI = 0.55-1.15, I2 = 89.0 %), CRP (SMD = 0.69, 95%CI = 0.38 to 1.02, p < 0.0001), IL-6 (SMD = 5.70, 95%CI = 1.91 to 9.50, p = 0.003), TNF-a (SMD = 3.78, 95%CI = 0.63 to 6.92, p = 0.019), and PLR (SMD = 1.38, 95%CI = 0.50 to 2.28, p = 0.02) in the CSX group in comparison with healthy controls.

CONCLUSION

The results of this study showed that CSX leads to a significant increase in inflammatory biomarkers, including NLR, CRP, IL-6, TNF-a, and PLR.

Helicobacter pylori Infection—A Risk Factor for Irritable Bowel Syndrome? An Updated Systematic Review and Meta-Analysis

Nowadays, the relationship between Helicobacter pylori infection (HPI) and irritable bowel syndrome (IBS) remains controversial. Objective: The aim of this study is to investigate the relationship between HPI and IBS through a systematic review and meta-analysis based on the current evidence. Methods: We performed a systematic literature search in electronic databases (PubMed, EMBASE, and the Cochrane library) by computer to identify all reports published before 8 August 2021. The odds ratio (OR) and confidence interval (CI) were calculated to evaluate the association between HPI and IBS. Subgroup analyses were conducted for further assessment and exploration of heterogeneity sources. In addition, we assessed publication bias through funnel plots, Egger’s test, and Begg’s test. Finally, we conducted a sensitivity analysis to evaluate the robustness of the results. Results: Thirteen studies with 13,173 participants were included in the meta-analysis. The pooled OR of the association between HPI and IBS was 1.03 (95% CI [0.80,1.31]; p = 0.84). The adjusted OR of the association between HPI and IBS after excluding the studies with confounding factors defined by our team was 1.29 (95% CI [1.03,1.62]; p = 0.03). We found a positive association between HPI and IBS-D (diarrhea subtype) (OR: 1.54; 95% CI [1.22,1.95]; p = 0.0003). The OR of the relationship between cytotoxin-associated gene A (Cag A) positive HPI and IBS was 4.3 (95% CI [0.51,36.17]; p = 0.18). Conclusions: The likelihood of HPI in IBS patients is relatively higher than that of non-IBS participants but not statistically significant, implying that HPI is not significantly associated with IBS, albeit we may underestimate this association. Moreover, we found a positive association between HPI and IBS-D. We also observed an increased likelihood of Cag-A positive HPI in IBS patients than that of non-IBS participants but not statistically significant.

Helicobacter pylori Infection Maybe a Risk Factor for Cardiac Syndrome X

Purpose

Cardiac syndrome X (CSX) is a condition with normal coronary angiography but angina pectoris. Chronic inflammation caused by Helicobacter pylori (H. pylori) infection may play a pathogenic role in CSX. Therefore, we conducted a meta-analysis to explore the relationship between H. pylori infection and risk of CSX.

Methods

A systematic search in the Web of Science, Medline, Embase and Chinese databases (CNKI and Wanfang) was conducted up to October 2021. Articles on the association between H. pylori infection and the risk of CSX were included and were analyzed by R software (version 4.1.0).

Results

Ten case-control studies involving 703 CSX patients and 731 healthy controls were included. H. pylori infection was associated with an increased risk of CSX (OR: 8.29, 95% CI: 4.64–14.82). We also found a significant association in those 25–40 years of age (OR: 1.34, 95% CI: 1.04–1.72), those 40–50 years of age (OR: 11.27, 95% CI: 4.29–29.61), those over 50 years of age (OR: 7.18, 95% CI: 3.59–14.36), those in developing countries [Iran (OR: 12.99, 95% CI: 8.61–19.60) and China (OR: 5.14, 95% CI: 3.09–8.56)]. However, this association was not apparent in a developed country [Italy (OR: 0.93, 95% CI: 0.37–2.33)].

Conclusions

Our study suggested a possible association between H. pylori infection and the risk of CSX. Its pathogenicity is stronger in middle-aged individuals and some developing countries. However, more studies are needed to further investigate whether early eradication of H. pylori can reduce the incidence rate of CSX, especially in middle-aged individuals and some developing countries.

Helicobacter pylori: Commensal, symbiont or pathogen?

This review considers the data on Helicobacter pylori (H. pylori), which have been accumulated over 40 years since its description as an etiological factor in gastrointestinal diseases. The majority of modern publications are devoted to the study of the pathogenic properties of the microorganism in the development of chronic gastritis, peptic ulcer disease, and gastric cancer, as well as methods for its eradication. However, in recent years, there have been more and more studies which have suggested that H. pylori has a beneficial, or potentially positive, effect on the human body. The authors have attempted to objectively analyze the information accumulated in the literature on H. pylori. Some studies consider it as one of the recently identified human bacterial pathogens, and special attention is paid to the evidence suggesting that it is probably part of the composition of the human microbiome as a commensal (commensal from French to English is a table companion) or even a symbiont. The presented data discussing the presence or absence of the effect of H. pylori on human health suggest that there is an apparent ambiguity of the problem. The re-assessment of the data available on H. pylori infection is important in order to answer the question of whether it is necessary to create a program of mass H. pylori eradication or to apply a more personalized approach to treating patients with H. pylori-associated gastrointestinal diseases and to perform eradication therapy.

Receptor for advanced glycation end products gene polymorphisms in cardiac syndrome X

Endothelial and microvascular dysfunction serve important roles in the formation and pathogenesis of cardiac syndrome X (CSX). Expression of receptor for advanced glycation end products (RAGE) is suggested to be increased in several conditions, including diabetes, inflammation and vascular diseases. In the present study, RAGE gene polymorphisms in patients with CSX and healthy controls were investigated. A total of 114 patients, diagnosed with CSX using coronary angiography results following complaints of angina and objective ischemia, and 103 healthy controls participated in the study. Whether there was a difference in genotype distributions of RAGE gene -374T/A, -429T/C and Glys82Ser polymorphisms between patients with CSX and healthy controls was investigated. Following DNA isolation from blood samples of the participants, the polymorphic regions were examined by quantitative polymerase chain reaction, and the genotyping results were statistically analyzed. When the genotypic distributions of -374T/A, -429T/C and Gly82Ser polymorphisms were investigated in patients with CSX and healthy controls, no statistically significant differences were identified between the two groups (P>0.05). Likewise, no statistically significant differences were observed in the allelic distributions of all 3 polymorphic regions (P>0.05). To the best of our knowledge, the present study also investigated the association between CSX and RAGE gene polymorphisms for the first time. No statistically significant differences in RAGE gene polymorphisms between the CSX and control groups were observed. We hypothesized that significant results may be obtained by increasing the numbers of patients and healthy controls in future studies.

Increased levels of angiogenic factors in microvascular angina

Background

Recent studies have suggested that angiogenic factors may affect vascular endothelial integrity. On the other hand, endothelial dysfunction is the main pathological mechanism in microvascular angina (MVA) or cardiac syndrome X. Therefore, we aimed to determine the levels of angiogenic factors in MVA patients. In addition, we investigated the effects of metoprolol, as a beta blocker agent, on the serum levels of these factors.

Methods

Thirty patients with MVA (17 female/13 male; mean age: 55.53±9.18 years) and twenty healthy controls (14 female/6 male; mean age: 51.40±9.16 years) were enrolled.

The serum amounts of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and tyrosine kinase-2 receptor (Tie-2) were measured in healthy controls, MVA patients at baseline and after metoprolol therapy (25 mg for one month) by enzyme-linked immunosorbent assay.

Results

The levels of Ang-2 and Tie-2 were significantly higher in MVA patients at baseline in comparison with controls (Ang-2: 277.02±186.08 vs.164.46±49.83 ng/l, P=0.011; Tie-2: 28.97±18.85 vs. 14.90±4.05 ng/ml, P=0.002; respectively). But this difference in the Ang-1 levels was not significant (P=0.829). Additionally, the levels of angiogenic factors in MVA patients after metoprolol therapy were not significantly changed in comparison with the baseline status (P>0.05).

Conclusion

Our results considered a possible role for angiogenic factors in the pathophysiology of MVA, which need further investigation for elucidation. In addition, this study has not showed an effective role for metoprolol in changing the angiogenic factors levels as a therapeutic agent in MVA.

Helicobacter pylori and extragastric diseases: A review

Helicobacter pylori (H. pylori) infection is very common and affects approximately half of the world population. It causes gastric diseases, but some authors have reported an association of H. pylori infection with other systemic manifestations beginning in 1994. The list of potential effects of H. pylori outside the stomach includes a number of extragastric manifestations and we focused on neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, allergic, and hepatobiliary diseases. This review discusses these important reported manifestations that are not related to the gastrointestinal tract.

The association between cardiac and gastrointestinal disorders: causal or casual link?

Cardiovascular diseases are the leading cause of death worldwide: among them, coronary artery disease and arrhythmias represent the most frequent pathological conditions. Similarly, the gastrointestinal disorders, that is, gastroesophageal reflux and inflammatory bowel diseases, have a high incidence in the general population. Several pieces of evidence have documented a link between cardiac and gastrointestinal disorders as they often share similar risk factors and symptoms. Furthermore, both can simultaneously occur in the same patient, thus creating problems in the correct clinical diagnosis. It is well known that gastrointestinal disorders may present with chest pain and mimic angina pectoris. In contrast, they can also unmask heart disease, such as in the case of the angina-linked ischemia. The aim of this review was to elucidate the mechanisms underlying the relationship between cardiac and gastrointestinal diseases to better understand the causal or casual character of such a linkage.

Association of endothelial dysfunction and cytotoxin-associated gene A-positive Helicobacter pylori in patients with cardiac syndrome X

Background

Existence of coronary endothelial dysfunction has been demonstrated in patients with cardiac syndrome X (CSX). In addition, Helicobacter pylorus (H. pylori) has been associated with CSX. We aimed to assess the possible association of endothelial dysfunction and cytotoxin-associated gene A-positive H. pylori (CagA+) infection in CSX patients.

Methods

Fifty-six patients with CSX (23 male/33 female; age: 51.25 ± 8.86 years) who were anti-H. pylori IgG-positive [H. pylori(+)] and 24 CSX patients (7 male/17 female; age: 52.79 ± 9.88 years) who were H. pylori(−) were included. Also, anti-H. pylori IgG-positive patients were determined by the presence of IgG antibody to CagA. Levels of endothelin-1 (ET-1), E-selectin and intercellular adhesion molecule-1 (ICAM-1) were measured.

Results

Endothelial dysfunction biomarkers were higher in H. pylori(+) than in H. pylori(−) patients (ET-1: 54.60 ± 25.39 vs. 42.59 ± 18.37 pg/ml, p = 0.04; E-selectin: 42.68 ± 14.26 vs. 31.72 ± 8.26 ng/ml, p = 0.001; ICAM-1: 339.68 ± 135.8 vs. 266.51 ± 125.1 ng/ml, p = 0.02). Among H. pylori(+) subjects, 28 cases were CagA(+) and 28 cases were CagA(−). There were significant differences in measured levels of E-selectin between CagA(+) and CagA(−) groups (48.00 ± 16.37 vs. 37.37 ± 9.37 ng/ml, p = 0.004). For ET-1 and ICAM-1 levels, the difference between CagA(+) and CagA(−) was insignificant (p = 0.174 and p = 0.07, respectively).

Conclusion

High levels of endothelial dysfunction biomarkers are found in CSX patients with anti-CagA(+). These findings suggest the infection with CagA(+) H. pylori strain may play a role as a risk factor in development of CSX through provocation of endothelial dysfunction. Therefore, a long term follow up to investigate the outcomes of these patients is proposed.

Human Endothelial Cell-Specific Molecule-1 (Endocan) and Coronary Artery Disease and Microvascular Angina

Endothelial cell-specific molecule-1 (endocan) is an immunoinflammatory marker linked to endothelial activation and dysfunction. We investigated the relationship between obstructive coronary artery disease (CAD), microvascular angina (MVA), and plasma levels of endocan. We included 53 healthy individuals as controls, 40 MVA patients, and 120 patients with obstructive CAD. The severity of CAD was assessed by the Gensini and SYNergy between percutaneous coronary intervention with TAXUS and Cardiac Surgery (SYNTAX) scores. Endocan levels were 382.7 (313.8-470.2) pg/mL in patients with obstructive CAD; 324.3 (277.1-460.7) pg/mL in MVA group, and 268.0 (226.4-336.5) pg/mL ( P < .001) in controls. Endocan levels in obstructive CAD and MVA groups were similar but both were significantly higher than for the control group ( P < .001 and P = .002, respectively). In subgroup analysis, similar to the hypertensive subgroup results, endocan was still an independent predictor of presence of obstructive CAD in normotensives (odds ratio = 1.005, 95% confidence interval = 1.001-1.010, P = .024). There was also an independent positive correlation between endocan levels and SYNTAX score both in the hypertensives (β = 0.414, t = 3.21, P = .002) and in the normotensives (β = .301, t = 2.23, P = .031). In conclusion, endocan could be a common predictor of the endothelium-dependent inflammatory processes, rather than related with specific risk factors.

Lipid Profile in Cardiac Syndrome X: Association with Helicobacter pylori

INTRODUCTION

Chronic inflammation caused by Helicobacter pylori (H.pylori) infection has a pathogenic role in Cardiac Syndrome X (CSX). In addition, it has shown that bacterial infection may affect blood lipids.

AIM

To assess if H.pylori affects the level of lipid profile in CSX.

MATERIALS AND METHODS

Eighty-eight CSX patients and 97 healthy controls were enrolled. The Total Cholesterol (TC), Triglyceride (TG), Lipoprotein A (LP{A}), Low Density Lipoprotein (LDL), High Density Lipoprotein (HDL), Apoprotein A1 (APOA1), and Apoprotein B (APOB) was estimated colorimetrically. In addition, the presence of IgG antibody to H.pylori was tested in plasma samples by using enzyme linked immunosorbent assay method.

RESULTS

TC, LP{A}, LDL, APOA1 and APOB levels in CSX group were significantly higher than those of the control group (p<0.05). But, these parameters in H.pylori positive and H.pylori negative, among CSX and control groups were not significant.

CONCLUSION

Increased plasma level of lipid profile and H.pylori infection were associated with CSX; it seems that plasma lipid disorders have a significant role in the development of CSX.

LACK OF ASSOCIATION BETWEEN HELICOBACTER PYLORI'S VIRULENCE AND INCREASED SERUM C-REACTIVE PROTEIN LEVELS IN FUNCTIONAL DYSPEPTIC PATIENTS

ABSTRACT Background Recently, a great variety of studies aimed to investigate and even suggestHelicobacter pylori as an important key factor in gastrointestinal and non-gastrointestinal events development. The well-established relationship between bacterial virulence and increased risk for peptic ulcer or gastric carcinoma is not so clear when comparing inflammation markers alterations, such C-reactive protein, with the pathogen. Objective The objective of this study was to evaluate the presence of H. pylori, bacterial virulence and C-reactive protein serum levels in individuals diagnosed with functional dyspepsia. Methods Were prospectively included in this study 489 dyspeptic individuals. They fulfill Rome III clinical criteria for the diagnosis of functional dyspepsia with no organic disease at endoscopy. The bacterial infection was established by histology and urease rapid test. The levels of serum C-reactive protein were obtained by immunonefelometry and CagA status ofH. pylori positive individuals was determined through an imunoenzimatic assay. Results Prevalence rate of H. pylori was 66.3% and virulence factor CagA was detected in nearly 43% of positive samples. In addition, it has been noticed an association between Ilex paraguariensis(yerba maté) consumption and pathogen's prevalence. An important effect of bacterial infection on inflammation was only observed in gastric epithelium. Conclusion No systemic response to the pathogen, measured through C-reactive protein levels, was observed, regardless of CagA status. Otherwise, the intake of yerba maté should be considered as a cultural factor possibly related toH. pylori's transmission.

Influence of H. pylori CagA Coupled with Alcohol Consumption on Cytokine Profiles in Men

The aim of this study was to evaluate the effect of Helicobacter pylori (H pylori) cytotoxin-associated gene A (CagA) coupled with chronic alcohol ingestion on cytokine profiles.A total of 215 male subjects were divided into the following 4 groups: 130 alcohol H pylori CagA-negative consumers (CagA-) (group A), 50 alcohol H pylori CagA-positive consumers (CagA+) (group B), 24 nonalcohol H pylori CagA-negative consumers (group C), and 11 nonalcohol H pylori CagA-positive consumers (group D). The serum CagA, C-reactive protein (CRP), interleukin (IL)-6, IL-10, E-selectin, adiponectin (ADP), and tumor necrosis factor-α (TNF-α) levels were measured through enzyme-linked immunosorbent assays (ELISAs).After adjusting for age and mean alcohol drinking history, a multivariable linear regression analysis revealed that the mean daily alcohol consumption, IL-6, TNF-α, and ADP levels were significantly increased with increases in the serum CagA concentrations (P = 0.008, P = 0.000, P = 0.000, and P = 0.006, respectively). The serum IL-6 and IL-10 levels of group A were significantly lower than those of group B (all P = 0.000). Furthermore, the serum IL-6 and IL-10 levels of groups A and C were significantly lower than those of group D (all P = 0.000), and the serum IL-6 and IL-10 levels of group C were significantly lower than those of group B (all P = 0.000). The serum ADP and E-selectin levels of groups B and D were significantly higher than those of group A (P = 0.000). The serum ADP levels of group B were significantly higher than those of group C (P = 0.000), and the serum ADP and E-selectin levels of group C were significantly lower than those of group D (P = 0.000 and P = 0.005, respectively). Finally, the serum TNF-α levels of groups B, C, and D were significantly higher than those of group A (all P = 0.000), and the serum TNF-α levels of group C were significantly higher than those of group D (P = 0.005).In conclusion, H pylori CagA may result in significantly higher levels of several inflammatory markers in both alcohol consumers and nonalcohol consumers. However, chronic alcohol ingestion coupled with H pylori CagA positivity does not result in significant changes in cytokine profiles.

Effect of H. pylori Infection on Cytokine Profiles and Oxidative Balance in Subjects with Chronic Alcohol Ingestion

Different amounts of ingested alcohol can have distinct effects on the human body. However, there is limited research on chronic alcohol consumption with Helicobacter pylori infection. We sought to investigate the relationship between the cytokine profile, oxidative balance and H. pylori infection in subjects with chronic alcohol consumption. A total of 142 subjects were divided into three groups: 59 subjects with chronic alcohol ingestion and H. pylori infection (group A); 53 subjects with chronic alcohol ingestion without H. pylori infection (group B); and 30 control subjects (group C). The serum levels of CagA, interleukin (IL)-10, E-selectin, TNF-α, malondialdehyde (MDA) and superoxide dismutase (SOD) activity were measured by enzyme-linked immunosorbent assay (ELISA). We found that the ages and serum H. pylori CagA levels among the three groups, as well as both the mean drinking age and the mean daily alcohol consumption between groups A and B, were matched and comparable. Comparing the BMIs among the three groups, the BMI differences were found to be statistically significant (F=3.921, P<0.05). Compared with group C, the BMIs in groups A and B were significantly higher (P<0.001 and P<0.01, respectively); however, the BMI differences between group A and group B were not statistically significant (P>0.05). Additionally, no differences in the serum CagA levels were found in comparisons among the groups (all P>0.05). The serum IL-10 and E-selectin levels in group A were significantly lower than those in group B (serum IL-10: P<0.05; E-selectin: P<0.05). The serum IL-10 in group A was significantly higher than that in group C (P<0.01); the serum E-selectin levels in group A did not significantly differ compared with those in group C (P>0.05). Furthermore, the serum IL-10 and E-selectin levels in group B were significantly higher than those in group C (serum IL-10: P<0.001; E-selectin: P<0.05); however, the serum TNF-α levels did not differ among groups (all P>0.05). Although the serum levels of MDA and SOD in groups A and B were slightly lower than those in group C, there were no significant differences among groups (all P>0.05). In conclusion, we believe that H. pylori infection might cause a significant inhibition of certain cytokine profiles in subjects with chronic alcohol ingestion. Moreover, chronically ingested alcohol may exert an adjusted inflammatory effect, but there was no association between H. pylori infection, chronic alcohol consumption and oxidative balance.

Influence of Helicobacter pylori infection on metabolic parameters and body composition of dyslipidemic patients

Helicobacter pylori infection may contribute to the development of extra-gastroduodenal diseases. The aim of this study was to explore whether this infection could influence metabolic parameters and body composition of dyslipidemic patients. In an 8-month period, 155 patients attended our clinic; 110 patients (48 men and 62 women, age 35-55 years) fulfilled inclusion criteria. Metabolic parameters were determined by routine tests and body composition by anthropometry and bioelectrical impedance analysis. The H. pylori and CagA infectious status were examined serologically. Sixty-one patients (55.4%) had serum antibodies to H. pylori and 30 infected patients (49.1%) had anti-CagA antibodies. The mean percentage of fat mass and level of high-density protein cholesterol in seropositive patients were significantly lower than those measured in seronegative ones (P = 0.008 and P < 0.001, respectively). The mean glucose concentration in patients with anti-H. pylori serum IgG was significantly higher than in uninfected patients (P = 0.021). No significant difference was observed regarding the other parameters. The CagA status did not influence any of the considered parameters. Our results are in agreement with those of other studies; however, the level of concordance of results reported in the various publications on this topic is very low, presumably from differences concerning the age, alimentary habits and possible presence of different pathologies in the groups studied. The most plausible hypothesis for the observed alterations may exist in the low-grade systemic inflammatory status of infected individuals, which may influence the fat turnover and support the insulin resistance with consequent alteration of glucose metabolism.

Beyond the stomach: An updated view of Helicobacter pylori pathogenesis, diagnosis, and treatment

Helicobacter pylori (H. pylori) is an extremely common, yet underappreciated, pathogen that is able to alter host physiology and subvert the host immune response, allowing it to persist for the life of the host. H. pylori is the primary cause of peptic ulcers and gastric cancer. In the United States, the annual cost associated with peptic ulcer disease is estimated to be $6 billion and gastric cancer kills over 700000 people per year globally. The prevalence of H. pylori infection remains high (> 50%) in much of the world, although the infection rates are dropping in some developed nations. The drop in H. pylori prevalence could be a double-edged sword, reducing the incidence of gastric diseases while increasing the risk of allergies and esophageal diseases. The list of diseases potentially caused by H. pylori continues to grow; however, mechanistic explanations of how H. pylori could contribute to extragastric diseases lag far behind clinical studies. A number of host factors and H. pylori virulence factors act in concert to determine which individuals are at the highest risk of disease. These include bacterial cytotoxins and polymorphisms in host genes responsible for directing the immune response. This review discusses the latest advances in H. pylori pathogenesis, diagnosis, and treatment. Up-to-date information on correlations between H. pylori and extragastric diseases is also provided.

CagA-positive Helicobacter pylori infection and reduced sperm motility, vitality, and normal morphology

Helicobacter pylori (HP) infection, particularly when caused by strains expressing CagA, may be considered a concomitant cause of male and female reduced fertility. This study explored, in 87 HP-infected males, the relationship between infection by CagA-positive HP strains and sperm parameters. HP infection and CagA status were determined by ELISA and Western blotting; semen analysis was performed following WHO guidelines. The amino acid sequence of human enzymes involved in glycolysis and oxidative metabolism were “blasted” with peptides expressed by HP J99. Thirty-seven patients (42.5%) were seropositive for CagA. Sperm motility (18% versus 32%; P < 0.01), sperm vitality (35% versus 48%; P < 0.01) and the percentage of sperm with normal forms (18% versus 22%; P < 0.05) in the CagA-positive group were significantly reduced versus those in the CagA-negative group. All the considered enzymes showed partial linear homology with HP peptides, but four enzymes aligned with four different segments of the same cag island protein. We hypothesize a relationship between infection by strains expressing CagA and decreased sperm quality. Potentially increased systemic levels of inflammatory cytokines that occur in infection by CagA-positive strains and autoimmune phenomena that involve molecular mimicry could explain the pathogenetic mechanism of alterations observed.