PREVALENCE AND RISK FACTORS FOR COLONIZATION AND INFECTION WITH EXTENDED-SPECTRUM β-LACTAMASES PRODUCING Enterobacteriaceae IN HOSPITALIZED NEONATAL FOALS

Introduction: Multidrug-resistant bacteria are a worldwide concern in human and veterinary medicine. In human neonates, Extended-Spectrum β-Lactamases producing Enterobacteriaceae (ESBL-E) were identified as a cause of infections outbreaks. In neonatal foals, bacterial infection, leading to sepsis, is a major cause of death. Thus, early treatment with appropriate antimicrobials is crucial. Aims: To determine prevalence and risk factors for ESBL-E colonization and infection in neonatal foals on admission to hospital and during hospitalization.

M&M: A prospective study (December 2015- June 2016) was performed in the veterinary medicine teaching hospital. Paired rectal swabs were sampled from mares and their neonate foals (≤ one month old). ESBL-E were recovered from enriched swabs, after plating onto CHROMagarESBL plates. Bacterial species and antibiotic susceptibility profiles were determined using Vitek2. Medical records were collected and assessment of risk for individual variables was performed by univariate analysis (SPSS).

Results: 59 foals and 54 mares were samples on admission, 60% (36/59) of foals and 56% (30/54) of mares were re-sampled during hospitalization. On admission, 36% (n=21/59) of foals were colonized with ESBL-E. During hospitalization, 80% (29/36) of foals were colonized. Foals` colonization was significantly connected to umbilical infection on admission (P=0.026) and not connected to mares` colonization. Main bacterial species were E. coli and K. pneumonia. Species diversity increased during hospitalization. Resistance rates increased during hospitalization for amoxicillin-clavulanate, aminoglycosides, trimethoprim-sulfa and chloramphenicol. ESBL-E were also recovered from clinical samples, including umbilicus and wounds.

Conclusion: ESBL-E colonization in neonatal foals is connected to umbilical infection. Colonization rate increases during hospitalization and might be connected to clinical infections.