Helicobacter pylori Western cagA genotype in Egyptian patients with upper gastrointestinal disease

Helicobacter pylori and oral-gut microbiome: clinical implications

More than half of the world's population are colonized with H. pylori; however, the prevalence varies geographically with the highest incidence in Africa. H. pylori is probably a commensal organism that has been associated with the development of gastritis, ulcers, and gastric cancer. H. pylori alone is most probably not enough for the development of gastric carcinoma, but evidence for its association with the disease is high and has, therefore, been classified by the International Agency for Research on Cancer as a Class 1 carcinogen. Bacteroidetes and Fusobacteria positively coexisted during H. pylori infection along the oral-gut axis. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Therefore, therapy regimens integrated with probiotics may abolish the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient's compliance. The eradication therapy not only affects gut microbiome but also affects the oral microbiome with robust predominance of harmful bacteria. However, there have been reports of a protective role of H. pylori in Barrett's esophagus, esophageal adenocarcinoma, eosinophilic esophagitis, IBD, asthma, and even multiple sclerosis. Therefore, eradication therapy should be carefully considered, and test to treat policy should be tailored to specific communities especially in highly endemic areas. Supplementation of probiotics, prebiotics, herbals, and microbial metabolites to reduce the negative effects of eradication therapy should be considered. After failure of many eradication attempts, the benefits of H. pylori eradication should be carefully balanced against the risk of adverse effects especially in the elderly, persons with frailty, and intolerance to antibiotics.

Frequency and risk factors of H. pylori infection among dental students: an observational cross-sectional study

Despite Helicobacter pylori infection remains asymptomatic in most people, it is associated with an increased risk of gastric cancer. Considering Egypt had the highest prevalence of H. pylori in healthy asymptomatic population in adults and pediatric age in past studies and currently salivary ELISA could be used for diagnosis of Oral H. pylori infection. Moreover, some researchers speculated that dentists and dental students might be at a higher risk for oral H. pylori infection because they are the most frequently exposed ones to saliva and dental plaque. This study aimed to determine risk factors associated with frequency of H. pylori among a sample of dental students for better management of the disease. 83 participants, with age (21-25 years), attending Faculty of Dentistry, Fayoum University were recruited. A structured questionnaire was used to collect information on sociodemographic parameters and risk factors for H. pylori. Direct inquiry about dyspeptic symptoms were done. Saliva samples were collected and tested for H. pylori antibodies. Overall seroprevalence was 22.9%. Participants in internship were more prone to be positive (p = 0.005). 32.6% of urban residents versus 10.8% of rural were H. pylori positive (p = 0.019). 75.0% of previous history of H. pylori infection versus 14.1% of those with no history were H. pylori positive p < 0.001. 70% of positive H. pylori participants reported positive clinical symptoms that were statistically significant. This study suggests that middle income, previous history of H. pylori and clinical symptoms of dyspepsia are risk factors of oral H. pylori with a decline in its prevalence in Egypt.

Regulatory B cells (Bregs) in Helicobacter pylori chronic infection

BACKGROUND

Helicobacter pylori (H. pylori) infection is linked with a wide variety of diseases and was reported in more than half of the world's population. Chronic H. pylori infection and its final clinical outcome depend mainly on the bacterial virulence factors and its ability to manipulate and adapt to human immune responses. Bregs blood levels have been correlated with increased bacterial load and infection chronicity, especially Gram-negative bacterial infection. This study aimed to identify prevalence and virulence factors of chronic H. pylori infection among symptomatic Egyptian patients and to examine its possible correlation to levels of regulatory B cells (Bregs) in blood.

MATERIALS AND METHODS

Gastric biopsies and blood samples from each of 113 adult patients, who underwent upper endoscopy, were examined for the detection of H. pylori by culture and PCR methods. Conventional PCR was used to determine various virulent genes prevalence and association to clinical outcome. Flow cytometry was used to evaluate Bregs levels.

RESULTS

Helicobacter pylori prevalence was 49.1% (55/112). Regarding virulence genes incidence, flaA gene was detected in 73% (40/55), vir B11 in 56.4% (31/55), hopZ1 in 34.5% (19/55), hopZ2 in 89% (49/55), babA2 in 52.7% (29/55), dupA jhp917 in 61.8% (34/55), vacA m1/m2 in 70.9% (39/55), and vacA s1/s2 in 69% (38/55) strains. Bregs levels were significantly lower in H. pylori-infected patients (p = 0.013), while total leukocyte count (TLC) showed no significant differences.

CONCLUSION

Helicobacter pylori infection prevalence was almost 49%, and the infection was found to be related to inflammatory conditions as gastritis and ulcers rather than malignant transformations. Also, we found that CD24⁺ CD38⁺ B cells were downregulated in H. pylori-infected patients.

Associations between seroprevalence of Helicobacter pylori and ABO/rhesus blood group antigens in healthy blood donors in southwest Iran

OBJECTIVE

To investigate correlations between ABO/rhesus (Rh) blood group antigens and anti-Helicobacter pylori and anti-cytotoxin-associated gene A (CagA) seropositivity in blood donors.

METHODS

A total of 311 blood donors were enrolled. ABO and Rh blood groups were determined using hemagglutination tests. Specific anti-H. pylori IgG and anti-CagA IgG antibodies in sera were quantitated by enzyme-linked immunosorbent assay. Correlations between blood groups and anti-H. pylori and anti-CagA seropositivity were evaluated using the Chi-square test.

RESULTS

O+ was the most frequent blood type (38%, n = 118). Anti-H. pylori IgG seropositivity was observed in 240 (77.2%) blood donors, while anti-CagA IgG seropositivity was observed in 132 (42.5%) blood donors. Although seropositivity rates for both anti-H. pylori and anti-CagA IgG were higher in individuals with blood type O, no statistically significant associations were observed between seropositivity and any ABO/Rh blood groups.

CONCLUSION

Individuals with blood type O may have higher rates of H. pylori seropositivity.

Synthesis and characterization of amoxicillin-loaded polymeric nanocapsules as a drug delivery system targeting Helicobacter pylori

BACKGROUND AND STUDY AIMS

Helicobacter pylori (H. pylori) is well known as the main cause of gastritis, gastroduodenal ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Approximately 50% of the world's population is infected with H. pylori. In Egypt, a high prevalence of H. pylori infections has been reported in the general population. This study aimed to prepare amoxicillin-loaded poly (ɛ-caprolactone) nanocapsules to increase its gastric stability and therapeutic activity of the molecule against H. pylori.

MATERIALS AND METHODS

In this study, we used the water-oil-water double-emulsion technique to prepare spherical-shaped polymeric nanocapsules containing amoxicillin trihydrate as the core substance and biodegradable biocompatible poly (ɛ-caprolactone) as the shell material.

RESULTS

The encapsulation efficiency obtained was 97.2% ± 0.8%. The hydrodynamic diameter of the prepared nanocapsules was 287 ± 8 nm with a positive zeta potential. In vitro release studies indicated that the polymeric nanocapsules showed decreased release percentages at pH 1.2, simulating the gastric fluid while relatively increased release at pH 7.0 where the H. pylori reside. The in vitro antibacterial assay showed better efficiency for amoxicillin nanocapsules than for the uncapsulated free amoxicillin, no efficiency was detected for the PCL nanocapsules indicated that the antibacterial due to amoxicillin alone. Cytotoxicity studies demonstrated less cytotoxicity for the polymeric nanocapsules in comparison with amoxicillin.

CONCLUSIONS

In conclusion, we have demonstrated that biodegradable polymeric nanocapsules are useful drug delivery agents for increasing the gastric stability and therapeutic activity of amoxicillin trihydrate against H. pylori.

Helicobacter pylori Infection in Africa: Update of the Current Situation and Challenges

BACKGROUND

The burden of Helicobacter pylori infection (HPI) in Africa remains high with varying levels of prevalence among children and adults reported in different regions of the continent. Persistent and uneradicated HPI could result in gastric cancer, although less severe pathological outcomes have been reported among Africans - the so-called "African enigma."

SUMMARY

Analysis of endoscopic findings of the upper gastrointestinal tract demonstrates similarities with that of patients from the West. Thus, it could be asserted that the true picture of HPI in Africa is yet to be unveiled due to several challenges including inadequate health-care system, lack of treatment guidelines and standardized protocol for diagnosis, and lack of data. This review explores the prevalence, diagnosis, treatment, and health-care system in Africa as it relates to HPI, thus providing an update and highlighting the need for an African HPI guideline.

KEY MESSAGES

There is high prevalence of Helicobacter pylori infection (HPI) in Africa with an increasing burden of antibiotic resistance. Various methods including invasive and noninvasive methods are deployed in the diagnosis of HPI in Africa. There is a need for consensus on diagnosis and treatment of HPI in Africa.

Diagnosis of Helicobacter pylori Infection in a Routine Testing Workflow: Effect of Bacterial Load and Virulence Factors

Reliable diagnostic methods are mandatory for effective management of Helicobacter pylori infection. Histology and culture are the most common invasive methods in current practice, even if molecular methods are gaining in importance. The performance of these conventional methods varies significantly. We conducted a retrospective study of 1540 adults and 504 children with gastric biopsies taken during endoscopy to assess the impact of bacterial load and the cagA virulence factor on the performance of H. pylori infection testing. The association between virulence and histology findings was also investigated. With 23S rRNA qPCR confirmed by glmM amplification as the gold standard, culture and histology had lower sensitivity, 74.4% and 73.3%, respectively. However, their sensitivity was enhanced (>90%) in biopsies with high bacterial load (qPCR Ct < 30). Positive cagA status of the strain was associated with high bacterial load (94.9%), thus resulting in more frequent positive culture (94.3%) and H. pylori histology detection (91.7%) and more severe lesions on histology (p < 0.001). Conversely, the cagA status of the strains was negative in 110/119 (92.4%) of biopsies with low bacterial load (qPCR Ct < 30), 82/90 (91.1%) with negative H. pylori histology detection and 119/131 (90%) with negative culture findings (p < 0.001). This study highlights the low sensitivity of conventional culture and histology that may lead to false negative diagnosis if used alone. H. pylori quantification associated with cagA genotyping in routine workflow are essential for a sensitive and reliable diagnosis, to identify patients at high risk and to manage eradication therapies.