Detection and characterization of ESBL-producing Enterobacteriaceae from the gut of healthy chickens, Gallus gallus domesticus in rural Nepal: Dominance of CTX-M-15-non-ST131 Escherichia coli clones.

The surge in the prevalence of drug-resistant bacteria in poultry is a global concern as it may pose an extended threat to humans and animal health. The present study aimed to investigate the colonization proportion of extended-spectrum ß-lactamase (ESBL) and carbapenemase-producing Enterobacteriaceae (EPE and CPE, respectively) in the gut of healthy poultry, Gallus gallus domesticus in Kaski district of Western Nepal. Total, 113 pooled rectal swab specimens from 66 private household farms and 47 commercial poultry farms were collected by systematic random sampling from the Kaski district in western Nepal. Out of 113 pooled samples, 19 (28.8%) samples from 66 backyard farms, and 15 (31.9%) from 47 commercial broiler farms were positive for EPE. Of the 38 EPE strains isolated from 34 ESBL positive rectal swabs, 31(81.6%) were identified as Escherichia coli, five as Klebsiella pneumoniae (13.2%), and one each isolate of Enterobacter species and Citrobacter species (2.6%). Based on genotyping, 35/38 examined EPE strains (92.1%) were phylogroup-1 positive, and all these 35 strains (100%) had the CTX-M-15 gene and strains from phylogroup-2, and 9 were of CTX-M-2 and CTX-M-14, respectively. Among 38 ESBL positive isolates, 9 (23.7%) were Ambler class C (Amp C) co-producers, predominant were of DHA, followed by CIT genes. Two (6.5%) E. coli strains of ST131 belonged to clade C, rest 29/31 (93.5%) were non-ST131 E. coli. None of the isolates produced carbapenemase. Twenty isolates (52.6%) were in-vitro biofilm producers. Univariate analysis showed that the odd of ESBL carriage among commercial broilers were 1.160 times (95% CI 0.515, 2.613) higher than organically fed backyard flocks. This is the first study in Nepal, demonstrating the EPE colonization proportion, genotypes, and prevalence of high-risk clone E. coli ST131 among gut flora of healthy poultry. Our data indicated that CTX-M-15 was the most prevalent ESBL enzyme, mainly associated with E. coli belonging to non-ST131clones and the absence of carbapenemases.

Detection of heterogeneous vancomycin-intermediate Staphylococcus aureus: A preliminary report from south India.

Background & objectives: Although there are reports of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) across the globe, there is a lack of reliable data on hVISA in India. The present study was undertaken to determine the rate of hVISA among the methicillin-resistant Staphylococcus aureus (MRSA) isolates, and to compare the brain heart infusion agar with vancomycin 4 µg/ml (BHIV4) method with population analysis profile-area under the curve (PAP-AUC) method for the detection of hVISA and to study the distribution of mobile genetic element that carries methicillin-resistance gene SCCmec (Staphylococcal cassette chromosome mec) types among these isolates. Methods: BHIV4 and PAP-AUC methods were employed to detect hVISA among 500 clinical isolates of MRSA. SCCmec typing of these isolates was performed by multiplex polymerase chain reaction. The clinical presentation, treatment with vancomycin and outcome was documented for patients with hVISA. Results: The rate of hVISA was 12.4 per cent by PAP-AUC method. Sensitivity, specificity, PPV, NPV and kappa agreement of BHIV4 with PAP-AUC was 58.06, 93.15, 54.55, 94.01 per cent and 0.498, respectively. The isolation of hVISA was significantly (P<0.01) higher in patients admitted to intensive care units and wards than in patients attending the outpatient departments. Only 38 per cent of the patients received vancomycin as therapy. Majority of the hVISA isolates carried SCCmec type V or IV. Interpretation & conclusions: The rate of hVISA isolation in our study was 12.4 per cent. The sensitivity of the BHIV4 screening test was low, and was in moderate agreement with PAP-AUC test. SCCmec type V was the predominant type seen in half of the isolates. More studies need to be done in different parts of the country on a large number of isolates to confirm our findings.

Neonatal sepsis due to glycopeptide resistant Enterococcus faecium from colonized maternal gut- rare case evidence.

Background: Vancomycin-resistant enterococcal infections in the neonatal ICU are growing global problems. We report a case of neonatal septicemia by multidrug-resistant vancomycin-resistant Enterococcus faecium (VRE), the source of infection being the mother's gut. Case presentation: A newborn male child admitted to the neonatal intensive care unit (NICU) was diagnosed to have mild meconium aspiration syndrome, early onset neonatal septicemia, and bacteremia by multidrug and vancomycin-resistant Enterococcus faecium. Screening of gut flora of the baby and the mother were carried out to trace the source of infection. Stool cultures of the mother and the baby yielded Vancomycin-Resistant Enterococcus faecium. All three isolates of Enterococcus faecium had similar antibiogram, harbored the vanA gene and similar pulsed-field gel electrophoresis pattern. Baby responded to the 1 week therapy with oral linezolid suspension 20 mg/kg/day, 1 ml/t.d.s. No VRE was isolated from baby on a repeat stool culture 1 week after the linezolid therapy. He was discharged with the advice for the continuance of linezolid for seven more days. Conclusion: Isolation of MDR-VRE from the blood culture of the baby and stool specimens of the mother and the baby with the same antibiogram profile and clonal similarities reveals that maternal gut colonization was responsible for neonatal sepsis. Optimal infection control measures and the development of guidelines for monitoring VRE colonization in pregnant women might be useful in reducing the occurrence of neonatal sepsis.

Risk factors for intestinal colonization with vancomycin resistant enterococci' A prospective study in a level III pediatric intensive care unit.

PURPOSE: Vancomycin-resistant enterococci (VRE) emerged as one of the major nosocomial pathogens across the globe. Gut colonization rate with VRE is higher in patients admitted to intensive care units (ICUs) due to the higher antibiotic pressure. VRE colonization increases the risk of developing infection up to 5-10 folds. The aim of this study was to determine the rates of VRE colonization among the patients admitted to pediatric ICU (PICU) and risk factors associated with it. MATERIALS AND METHODS: Rectal swabs were collected after 48 h of admission to PICU from 198 patients. The samples were inoculated onto bile esculin sodium azide agar with 6 mg/ml of vancomycin. Growth on this medium was identified by the standard biochemical test, and minimum inhibitory concentration of vancomycin and teicoplanin was detected by agar dilution method. Resistance genes for vancomycin were detected by polymerase chain reaction. Risk factors were assessed by logistic regression analysis. RESULTS: The rates of VRE colonization in patients admitted to PICU was 18.6%. The majority of the isolates were Enterococcus faecium (75.6%) followed by Enterococcus faecalis (24.4%). One patient acquired a VRE bloodstream infection (2.6%) among colonized patients, and none of the noncolonized patients acquired the infection. Consumption of vancomycin was found to be the only risk factor significantly associated with VRE colonization. CONCLUSION: Routine surveillance and isolation of patients found to be VRE colonized may not be possible in tertiary care hospitals; however, educating health-care workers, promoting handwashing with antiseptic soaps or solutions, and antibiotic Stewardship policy may help in the reduction of vancomycin resistance and VRE colonization.

Screening for Intestinal Colonization with Vancomycin Resistant Enterococci and Associated Risk Factors among Patients Admitted to an Adult Intensive Care Unit of a Large Teaching Hospital.

INTRODUCTION: Gut colonization with Vancomycin Resistant Enterococci (VRE) increases the risk of acquiring infection during hospital stay. Patients admitted in the ICU's are the major reservoirs for VRE colonization due to higher antibiotic pressure. AIM: To determine the rate of VRE colonization among patients admitted in the Medical Intensive Care Unit (MICU) and to assess the various risk factors which are associated with VRE colonization. MATERIALS AND METHODS: This was a prospective study carried out over a period of 18 months from September 2013 to February 2015 in the Jawaharlal Institute of Post graduate Medical Education and Research (JIPMER), Pondicherry, South India. After 48 hours of ICU admission rectal swabs were collected from a total of 302 patients, admitted in MICU. The samples were inoculated on to Bile Esculin Sodium Azide agar with 6mg/L of vancomycin. Vancomycin resistance was confirmed by determination of Minimum Inhibitory Concentration (MIC) by agar dilution method. Isolates were identified up to species level by standard biochemical tests. Vancomycin resistance genes such as van A, van B and van C, were detected by Polymerase Chain Reaction (PCR). Risk factors were assessed by multivariate logistic regression analysis. RESULTS: The rates of VRE colonization in patients admitted to MICU was 29%. Majority of the isolates were Enterococcus faecium (77.2 %) followed by Enterococcus faecalis (23.8%). All the VRE isolates were positive for van A gene. Increased duration of hospital stay, younger age, consumption of ceftriaxone and vancomycin were found to be significantly associated with VRE colonization in MICU. Among VRE colonized patients, six (4.5%) acquired VRE infection. CONCLUSION: The rates of VRE colonization in our ICU were similar to other hospitals worldwide. Educating health care workers on the importance of adherence to hand hygiene is essential to bring down VRE colonization rates.