Israel Medical Association Journal

Background: Antimicrobial resistance is the main determinant for Helicobacter pylori treatment failure. Regional antimicrobial susceptibility testing is essential for appropriate antibiotic selection to achieve high eradication rates.

Objectives: To assess primary and secondary H. pylori resistance in isolates recovered from Israeli naïve and treatment failures. To identify predictors of resistance.

Methods: In this retrospective study, in vitro activity of isolated H. pylori in Israel was tested against metronidazole, clarithromycin, tetracycline, amoxicillin, and levofloxacin in 128 isolates: 106 from treatment failures and 22 from naïve untreated patients. The minimal inhibitory concentration values were determined according to the Etest instructions. Treatment failures previously failed at least one treatment regimen.

Results: No resistance to amoxicillin and tetracycline was detected. Resistance to metronidazole and clarithromycin was high in H. pylori isolates both from treated and untreated patients: 68.9%, 68.2% for metronidazole (P = 0.95); 53.8%, 59.1% for clarithromycin (P = 0.64), respectively. Dual resistance to clarithromycin and metronidazole was seen in 45.3% and 50%, respectively (P = 0.68). Resistance to levofloxacin was detected in two (1.9%) isolates from treated patients. Simultaneous resistance to clarithromycin, metronidazole, and levofloxacin was seen in an isolate from a treated patient. Age was the only predictor of resistance to metronidazole and clarithromycin.

Conclusion: The resistance rates to both single and dual metronidazole and clarithromycin in isolates recovered from both Israeli naïve and treated patients is high. Low resistance renders levofloxacin an attractive option for second or third line treatment. Therapeutic outcome would benefit from susceptibility testing after treatment failure.

Background: Evidence has been emerging that Helicobacter pylori may also impact colorectal cancer (CRC). Positron emission tomography/computed tomography (PET/CT) imaging can predict overall survival in CRC patients.

Objectives: To determine a possible association between H. pylori seropositivity and all-cause mortality among CRC patients evaluated by PET/CT scans.

Methods: This prospective cohort study was comprised of 110 consecutive CRC patients who had undergone a PET/CT evaluation in a tertiary academic medical center. Data included demographics, body mass index (BMI), tumor node metastasis stage at diagnosis, treatment, time from diagnosis to PET/CT, and PET/CT findings. All patients were tested for anti-H. pylori immunoglobulin G (IgG) antibodies and followed for 36 months from the day of the PET/CT scan. Mortality was documented. Univariate and multivariate Cox regression was used to estimate the hazard ratio (HR) of H. pylori serological status.

Results: During the follow-up period, of the 110 CRC patients 41 (37.3%) died and 69 (62.7%) survived. Of the 41 patients, 26 (63.4%) were H. pylori seropositive and 15 (36.6%) were seronegative. Multivariate analysis showed that H. pylori seropositivity was associated with increased mortality (HR 3.46, 95% confidence interval 1.63–7.32), stage IV at diagnosis, metastatic disease found on PET/CT, longer time from diagnosis to PET/CT, lower BMI, and older age.

Conclusions: Our findings suggest that H. pylori infection may be a risk factor for all-cause mortality among CRC patients who are evaluated by PET/CT. Multicenter studies with larger patient groups are needed to confirm our findings.

Background: Empiric treatment for Helicobacter pylori is influenced by antibiotic susceptibility of infecting strains. A rise in the resistance rate to clarithromycin and metronidazole has been reported in pediatric populations.

Objectives: To assess the primary and secondary antibiotic resistance of H. pylori isolates in Israeli children and adolescents.

Methods: A retrospective review of H. pylori isolates cultured from antral biopsies of consecutive children aged 1 to 18 years, who were referred to the Pediatric Gastroenterology Unit, Kaplan Medical Center, over a 2.8 year period, was performed. Antibiotic susceptibility to clarithromycin, metronidazole, amoxicillin, tetracycline, and levofloxacin was determined by E-test. Data on the age of the patient, indication for endoscopy, and antibiotic treatment for H. pylori in previously treated children was collected.

Results: Cultures for H. pylori yielded 123 isolates. In children not previously treated (n=95), the primary global resistance was 38% with resistance to clarithromycin 9.5%, metronidazole 32.6 %, and to both 4.2%. Respective rates of resistance in previously treated children (n=28) were 71% (P = 0.002), 29% (P = 0.02), and 61% (P = 0.007). Simultaneous resistance to both drugs was found in 18% (P = 0.02). All H. pylori strains were susceptible to amoxicillin, tetracycline, and levofloxacin. Past eradication treatment was the only independent risk factor for antibiotic resistance in multivariate analysis.

Conclusions: Significantly higher resistance rates were found in previously treated patients, stressing the need to refrain from empiric treatment using the "test and treat strategy." Culture-based treatment strategy should be considered in all previously treated children.

Objectives: To investigate the association between CAD and H. pylori infection using MPI.

Methods: This prospective study evaluated CAD positivity among consecutive patients referred to a tertiary medical center for a stress/rest MPI. All patients were tested for serum anti-H. pylori and CagA protein immunoglobulin G antibodies. The CAD-positive group included patients with ischemia and/or myocardial infarctions (MI) on a stress MPI, coronary artery bypass graft surgery (CABG) or percutaneous coronary interventions (PCI). CAD-negative subjects were defined as participants with a normal MPI, no pathological Q waves in resting ECG tracing, and no history of CAD. Both groups were compared for H. pylori and CagA seropositivity. Patients’ demographic data, risk factors for CAD, and childhood socioeconomic status were recorded.

Results: The study group consisted of 300 consecutive patients, 170 men and 130 women; 64% (110/173) CAD-positive patients and 47% (60/127) CAD-negative participants were found seropositive for H. pylori infection (P = 0.005). In the adjusted analysis, H. pylori infection was found to be associated with CAD- positive (odds ratio 1.83, 95% confidence interval 1.06–3.17, P = 0.031), and MI (fixed perfusion defects on MPI) (OR 3.36, 95%CI 1.44–7.84, P = 0.005). No association was noted with CagA positivity.

Conclusions: In patients undergoing a stress MPI, serum anti-H. pylori antibodies positivity was found to be associated with CAD, independent of traditional cardiovascular risk factors. 

Background: Recurrent abdominal pain is a common pediatric diagnostic problem.  Endoscopy is sometimes performed as part of the evaluation. Although gastritis and/or Helicobacter pylori infection is often present, it is not known if they contribute to the symptomatology.

Objectives: To evaluate the role of either gastritis or H. pylori infection in the symptomatology of children with RAP.

Patients and Methods: We retrospectively studied two groups of patients, 70 children in each, who had undergone endoscopy. One group was evaluated endoscopically for RAP and the other was a heterogeneous group that underwent endoscopy for indications other than RAP. Biopsies were taken during endoscopy and Giemsa staining was performed for the presence of H. pylori. Triple therapy was given as indicated, and the children were followed for an average of 6 months.

Results: Microscopic gastritis was diagnosed in 39 patients (55.7%) of the RAP group and in 31 of the heterogeneous group (44.2%) (NS), and H. pylori was found in 32 patients of the RAP group and in 16 of the heterogeneous group (45.7% vs. 22.8%, P<0.01). All children with H. pylori, except one in the heterogeneous group, had accompanying gastritis. On the other hand, gastritis without H. pylori infection was seen in 7 children in the RAP group and in 15 of the other. Endoscopy revealed macroscopic abnormalities in 52 of the 70 children with microscopic gastritis. There was a clinical improvement after triple therapy in 28 of 33 children with H. pylori-associated gastritis (84.85%), in 4 of 8 children with gastritis unassociated with H. pylori (50%), and in 8 of 15 without gastritis or H. pylori (53.3%) (P<0.01 between the H. pylori-associated gastritis and each of the other groups).

Conclusions: H. pylori infection and gastritis may be associated with RAP in a selected subgroup of children. We recommend a complete work-up, including endoscopy and invasive or non-invasive diagnostic modalities for H. pylori, and treatment of the infection.

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RAP = recurrent abdominal pain