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: Urinary tract infection (UTI) is a common bacterial infection in children.

Early treatment may prevent renal damage in pyelonephritis. The choice of empiric antibiotic treatment is based on knowledge of the local susceptibility of urinary bacteria to antibiotics. In Israel the recommended empiric oral antibiotic treatment are First or second generation cephalosporin, trimethoprim-sulfamethoxazole or amoxicillin-clavulanic acid.

Objectives: To describe resistance rates of urine bacteria isolated from children with UTI in the community settings. Identify risk factors for resistance.

Methods: A retrospective cross-sectional study of UTI in children aged 3 months to 18 years diagnosed with UTI and treated as outpatients in a large community clinic between 7/2015 and 7/2017 with a diagnosis of UTI.

Results: A total of 989 urinary samples were isolated, 232 were included in the study. Resistance rates to cephalexin, cefuroxime, ampicillin/clavulanate and Trimethoprim-Sulfamethoxazole were 9.9%, 9.1%, 20.7%, and 16.5%, respectively. Urinary tract abnormalities and recurrent UTI were associated with an increase in antibiotic resistance rates. Other factors such as age, fever, and previous antibiotic treatment were not associated with resistance differences.

Conclusions: Resistance rates to common oral antibiotics were low compared to previous studies performed in Israel in hospital settings. First generation cephalosporins are the preferred empiric antibiotics for febrile UTI for outpatient children. Amoxicillin/clavulanate is not favorable due to resistance of over 20% and the broad spectrum of this antibiotic. Care should be taken in children with renal abnormalities as there is a worrying degree of resistance rates to the oral first line antibiotic therapy.

Background: Extended-spectrum beta-lactamase (ESBL) production is the most common antimicrobial resistance mechanism in the neonatal intensive care unit (NICU), with colonization and blood stream infections being a major threat to this population. Since 2013, all NICU admissions at our facility were screened twice weekly for ESBL colonization.

Objectives: To determine independent risk factors for colonization of infants with ESBL-producing bacteria in the NICU.

Methods: A retrospective case study of ESBL-colonized infants vs. controls (matched by date of birth and gestational age) was conducted in the NICU of Soroka University Medical Center, Israel, between 2013 and 2014. Epidemiological, laboratory, and clinical data were extracted from medical files. Univariable and multivariable analyses were used to assess associations between ESBL colonization and possible clinical risk factors.

Results: Of 639 admissions during the study period, 87 were found to be ESBL-colonized (case infants) and were matched to 87 controls. Five case infants became infected (5.7%) with ESBL strains. Klebsiella pneumoniae was the most common isolated bacteria. The mean time from admission to colonization was 15 days. Univariable analysis showed an association of male gender and highest Apgar score at 1 and 5 minutes with ESBL colonization (P < 0.05). Multivariable analysis yielded only a possible association of higher Apgar score at 1 and 5 minutes (hazard ratio [HR] 1.515, 95% confidence interval [95%CI] 0.993-2.314; HR 1.603, 95%CI 0.958–2.682, respectively) with ESBL colonization.

Conclusions: Future studies should focus on maternal colonization and possible strategies for preventing vertical transmission of ESBL strains to high-risk neonates.

Background: In an era of increasing antimicrobial resistance, knowledge of local antimicrobial susceptibility patterns of common uropathogens is essential for prudent empiric therapy of community-acquired urinary tract infections.

Objectives: To define antimicrobial susceptibility of Gram-negative uropathogens in northern Israel over a 10 year period and to compare it with antibiotic-use patterns in the same community.

Methods: We tested the susceptibility of all Gram-negative urinary isolates from outpatients at HaEmek Medical Center over the years 1995, 1999, 2002 and 2005 to common antimicrobial agents. MIC₉₀ of Escherichia coli to some of these agents was determined and antibiotic consumption data over the years 2000–2005 (DDD/1000/day) were obtained.

Results: We observed a rise in susceptibility rates of E. coli to amoxicillin-clavulanate, trimethoprim-sulfamethoxazole and nitrofurantoin and of other Gram-negative isolates to amoxicillin-clavulanate, ceftriaxone and cephalothin. Susceptibility rates of all Gram-negative uropathogens to ciprofloxacin decreased significantly. MIC₉₀ of E. coli for all drugs tested remained stable. There was a significant decrease in the use nitrofurantoin and TMP-SMX[1] and a significant increase in the use of ampicillin, cephalothin and ceftriaxone.

Conclusions: Antibiotic resistance patterns mostly remained unchanged or improved slightly. There was, however, a constant decrease in susceptibility of all Gram-negative uropathogens to ciprofloxacin. Antibiotic use patterns could not explain the changes seen in antibiotic susceptibility patterns.