Asymptomatic faecal carriage of vancomycin-resistant Enterococci among inpatients and outpatients in a Kenyan hospital: a cross-sectional study

This was a cross-sectional study design among adult patients (≥ 18) at the Kiambu County Referral Hospital outpatient department (OPD) and patients in the inpatient department (IPD) from June to September 2022. A systematic random sampling technique was employed to recruit 155 participants from the OPD, excluding patients presenting with histories of diarrhoea, antibiotics use (≤ 48 h), and ≤ 90 days previous admission. In IPD, 155 patients admitted for ≥ 48 h, were consecutively enrolled, excluding diarrhoea cases. The participants’ sociodemographic and clinical data were collected using a structured questionnaire, with stool samples collected in sterile containers and transported in an icebox to Kenya Medical Research Institute, Nairobi, for analysis within 4–6 h, using standard and automated bacteriological methods.

The overall faecal carriage of VRE was 5.2%, 95% confidence interval (CI): 2.98–8.25% (16/310), highest among the outpatients (3.9%; 12/310), 95% CI: 2.02–6.66%) where Enterococcus faecium predominated (overall: 62.5%, 10/16; IPD: 18.8%, 3/16; OPD: 43.8%, 7/16). VRE isolates were 100% resistant to erythromycin and tetracycline, with 31.3% (5/16) non-susceptible to teicoplanin, but remained sensitive to linezolid, tigecycline, and nitrofurantoin. Sixty-three per cent (62.5%, 10/16) of VRE isolates were multidrug-resistant, predominated by E. faecium (80%, 8/10). The multiple antibiotic resistance index (MARI) was > 0.2. The independent predictors of VRE carriage were female gender (aOR = 10.8, 95% CI 1.1-110.1, p = 0.045) and antibiotic dose completion behaviour (aOR = 0.122, 95% CI 0.0002-1.0, p = 0.046) among the outpatients.

We report asymptomatic faecal carriage of VRE strains that are MDR predominately among outpatients, whereby females and patients with a history of not completing an antibiotic prescription were at increased risk of colonization. To inform infection prevention interventions, establishing the transmission mechanisms and sustained AMR surveillance are warranted to mitigate VRE spread in our study area.