Acquisition of Antimicrobial-resistant E. coli Isolated
from Dogs admitted to a Veterinary Teaching Hospital
P. Nebbia
1, R. Odore
1, C. Tramuta
1, C. Crocillà
2, R. Zanatta
1, A. Borrelli
1,
L. Tomassone
1, R. Ferrillo
1, P. Robino
1Dip. di Scienze Veterinarie (Università di Torino)
Ospedale Civile di Rivoli (TO) ASL TO3
Introduction. The emergence of bacterial nosocomial infections has
become a major public health concern both for human and veterinary medicine. Commensal E. coli are a reservoir of resistance genes, that may be quickly acquired by pathogen bacteria. Monitoring intestinal E. coli isolated from hospitalized animals can be useful to improve strategies to minimize the development of antimicrobial resistance.
The aim of this work was to evaluate the effect of hospitalization on
antimicrobial resistance in E. coli isolated from dogs admitted to a Veterinary Teaching Hospital; to identify risk factors associated with acquisition and colonization of multidrug-resistant MDR bacteria (such as ESBL E. coli).
Materials and methods. A sample of 27 dogs were included in the study,
and anamnestic data were registered (e.g. sex, age, reason for admission, antimicrobial use, length of hospitalization). Fecal swabs were collected at admission (within 24 hours: T0) and during hospitalization (on day 3: T1). Health dogs (n=8), that remained for a long period in the dog park of the hospital, were included as controls. Standard bacterial culture procedures were used to recover E. coli from swabs. Identification of E. coli , ESBL- E.
coli and antibiotic sensitivity tests were carried out by BD-Phoenixtm. The antibiotics panel included antimicrobials commonly used in both veterinary and human medicine. Data were analyzed by descriptive statistics. McNemar's test was used to evaluate the change in ESBL E. coli over time, and Fisher Exact test to assess the association between risk factors (reason for hospitalization, previous hospitalization, etc.) and the development of antibiotic resistance.
Results. Paired admission (T0) and day 3 (T1) samples were
available for 27 dogs, with a total of 54 isolates of enteric E. coli.
During hospitalization, ESBL E. coli were acquired by 11 (40.5%)
animals. The proportion of ESBL E. coli increased over time (p < 0,01),
but it was not correlated to the use of antibiotics before and during
hospitalization. Control dogs showed high susceptibility to antibiotics
and their isolates were not ESBL producers. Antimicrobial sensitivity
tests carried out at the admission showed that 37% of animals were
already infected with ESBL and 55% were infected with multidrug
resistant strains.
Conclusions. Over the years, studies carried out on dogs admitted to
hospital showed that 7-10 days of residence are sufficient to acquire
MDR bacteria. Our work confirm this trend , but notably we observed
that animals could acquire resistant E. coli in just 3 days. This finding
is of relevance because, in the routine of veterinary hospitals, most of
the dogs are committed for no more than 72 hours.
+ 40.8% MDR-E. coli
References
•Bryan J, Leonard N , Fanning S, Katz L , Duggan V, 2010. Antimicrobial resistance in commensal faecal Escherichia coli of hospitalised horses. Irish Veterinary Journal, 63, 373-379.
•MaddoxT W, Williams NJ, Clegg PD, O’Donnell AJ, Dawson S, Pinchbeck GL, 2011. Longitudinal study of antimicrobial-resistant commensal Escherichia coli in the faeces of horses in an equine hospital. Preventive Veterinary Medicine, 100, 134-145.
•Williams A, Christley RM, McKane SA, Roberts VL, Clegg PD, Williams NJ, 2013. Antimicrobial resistance changes in enteric Escherichia coli of horses during hospitalisation: resistance profiling of isolates. Veterinary Journal, 195, 121-126.
Fig 1 - Dogs hospitalized Fig 2 - Anamnestic form
TAB 1 Antibiotic resistance patterns of 27 dogs at admission (T0) and on the third day (T1) of hospitalization.
