Impact of Helicobacter pylori eradication on refractory thrombocytopenia in patients with chronic HCV awaiting antiviral therapy

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.

Effectiveness of eradication therapy for Helicobacter pylori infection in Africa: a systematic review and meta-analysis

BACKGROUND

The effectiveness of Helicobacter pylori (H. pylori) eradication depends on the treatment protocol. This study investigates the H. pylori eradication rate in Africa using the best available evidence from databases.

METHODS

Databases were searched and results were pooled together. Heterogeneity between studies was assessed using I² test statistics. Stata version 13 software was employed to compute the pooled eradication rate. In the subgroup analysis comparison, the finding is considered significant when the confidence intervals did not overlap.

RESULTS

Twenty-two studies from 9 African countries with a total population of 2,163 were included in this study. The pooled eradication rate of H. pylori was 79% (95% CI: 75%-82%), heterogeneity (I² = 93.02%). In the subgroup analysis by study design, a higher eradication rate was reported from observational studies (85%, 95% CI: 79%-90%), compared to randomized control trials (77%, 95% CI: 73%-82%); by the duration of therapy, higher eradication rate was reported in 10-days regimen (88%, 95% CI: 84%-92%), compared to 7-days regimen (66%, 95% CI: 55%-77%); by country, the highest eradication rate was found in Ethiopia (90%; 95% CI: 87%-93%) and the lowest eradication rate was reported in Ivory Coast (22.3%; 95% CI:15%-29%); by type of H. pylori test, the highest eradication rate was reported when rapid urease test coupled with histology (88%, 95% CI: 77%-96%), and the lowest eradication rate was reported with histology alone (22.3%; 95% CI:15%-29%). Significant heterogeneity was observed with pooled prevalence (I² = 93.02%, P < 0.000).

CONCLUSIONS

In Africa, the first-line therapy showed a variable eradication rate for H. pylori. This study demonstrates the necessity to optimize current H. pylori treatment regimens in each country, taking into account the antibiotic susceptibility. Future RCT studies with standardized regimens are warranted.

Prevalence of CagA and antimicrobial sensitivity of H. pylori isolates of patients with gastric cancer in Egypt

BACKGROUND

Helicobacter pylori (H. pylori) infection has been recognized as a significant threat for gastric cancer. However, studies that investigated the oncogenic factors and antimicrobial resistance of H. pylori in Egyptian isolates with gastric cancer are rare. The current study aimed to examine: (1) The pattern of antimicrobial resistance of H. pylori isolates of Egyptian gastric cancer patients, and (2) the prevalence of Cytotoxin-associated gene A (CagA).

METHODS

Samples were collected from patients with gastric cancer. Isolation of H. pylori was performed using Columbia blood agar supplemented with 10% horse blood, and selective supplement of H. pylori for 3 to 5 days at 37 °C under microaerophilic condition. Isolates were identified by biochemical traits of H. pylori: oxidase, urease and catalase tests. Antimicrobial susceptibility of H. pylori isolates was examined against five antimicrobial agents using disc diffusion method. After that, extraction of DNA and Polymerase Chain Reaction (PCR) were performed to amplify the target genes.

RESULTS

Twelve samples were collected from six males and six females Egyptian patients with cancer with an age range from 22 to 65 years. These cases are scarce and samples were collected over a period of almost eleven months. All isolates were confirmed as positive H. pylori through colony morphology and biochemical tests. The most effective antibiotic found was ciprofloxacin whereas all isolates showed resistance to metronidazole and erythromycin. The target CagA oncogene gene with expected product size was reported and seven (out of twelve) isolates (58%) were identified as CagA positive.

CONCLUSION

The current study is unique in two main aspects. First, it reported the pattern of antimicrobial susceptibility and prevalence of CagA gene in H. pylori from Egyptian patients. Second, it exclusively recruited isolates from gastric cancer patients which were confirmed by clinical and laparoscopic examination. The moderately high prevalence of CagA gene in Egyptian cancer patients calls for more vigilance against that oncogene.

Helicobacter pylori infection among patients with liver cirrhosis

BACKGROUND AND AIM

Inflammatory changes in the stomach caused by Helicobacter pylori indirectly and directly affect liver function. Moreover, the bacteria may worsen the course of the liver cirrhosis. The study aimed at evaluating the incidence of H. pylori infection among patients with liver cirrhosis, depending on the etiology and injury stage, scored according to Child-Pugh classification. Stage of esophageal varices and endoscopic inflammatory lesions in the stomach were evaluated, depending on the presence of H. pylori infection.

PATIENTS AND METHODS

The study included 147 patients with liver cirrhosis: 42 were infected with hepatitis C virus, 31 were infected with hepatitis B virus, 56 had alcoholic liver cirrhosis, and 18 had primary biliary cirrhosis. Diagnosis of H. pylori infection was performed based on the presence of immunoglobulin G antibodies in serum.

RESULTS

H. pylori infection was found in 46.9% of patients. The incidence of H. pylori infection among patients with postinflammatory liver cirrhosis was significantly higher (P=0.001), as compared with patients with alcoholic liver cirrhosis. Ammonia concentration was significantly higher in patients infected with H. pylori, compared with noninfected individuals (129 vs. 112 μmol/l; P=0.002). Incidence of H. pylori infection in patients without esophageal varices was significantly lower compared with patients with esophageal varices (14 vs. 60%; P<0.001).

CONCLUSION

H. pylori infection is significantly more frequent among patients with postinflammatory liver cirrhosis (infected with hepatitis C virus or hepatitis B virus) than in patients with alcoholic liver cirrhosis or primary biliary cirrhosis. H. pylori infection correlates with elevated concentration of blood ammonia and the incidence of esophageal varices.