Israel Medical Association Journal

Background: Antibiotic resistance is a worldwide problem associated with increased morbidity and mortality.

Objectives: To evaluate multidrug resistant (MDR) bacteria carriage in selected populations.

Methods: Data were collected from all patients under 18 years who met our internal guidelines from 2015–2016. They were screened for carbapenem-resistant Enterobacteriaceae (CRE), extended spectrum beta-actamase (ESBL), methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Indications for screening were non-resident non-Israeli patients (from the Palestinian Authority, Syria, and foreign patients), internal transfers from intensive care units, admission to high-risk departments, recent carriage of MDR bacteria, transfer from other hospitals, and recent hospitalization. Data were analyzed for MDR bacteria from at least one screening site (rectal, nasal, axillary, groin, throat). All data were analyzed per patient and per sample.

Results: During the study period 185/2632 positive screening sets (7%) were obtained from 725 patients. Of these, 165 patients (22.7%) were positive for at least one pathogen. Significantly fewer Israeli residents (120/615, 19.5%) tested positive compared to non-Israeli residents (45/110, 40.9%; P < 0.001). Past MDR bacteria carriage was the only significant screening indication (25/61, 41%; P < 0.001). CRE, VRE, MRSA, and ESBL prevalence rates were 0.6% (5/771), 0.5% (3/560) 0.5%, 4.2% (37/888), and 33.7% (139/413), respectively. Among non-ESBL carriers, MRSA was predominant with 38 positive cultures (n=34).

Conclusions: Non-Israeli non-residents and patients with previous positive MDR screening are at higher risk for MDR bacteria. Indications used to identify high-risk patients for drug resistant pathogens were efficacious. More effort is needed to reduce excessive sampling.

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.