Antimicrobial Susceptibility Patterns in Urinary Tract Infections in Dogs (2010–2013)

Abstract

BackgroundUrinary tract infections (UTIs) are common in dogs. The responsible bacterial populations have evolved with increasing resistance to many antimicrobials.ObjectiveTo characterize the antimicrobial susceptibility patterns of canine urinary tract isolates over a 51‐month period.AnimalsOne thousand six hundred and thirty‐six bacterial isolates from 1,028 dogs.MethodsAerobic bacterial isolate growth and susceptibility data from urine cultures of dogs were identified, retrospectively. Medical records were reviewed to obtain signalment, comorbidities, and antimicrobial use in the previous 30 days. The UTIs were further categorized as uncomplicated, complicated, or pyelonephritis.ResultsCommon bacterial isolates identified were Escherichia coli (52.5%), Staphylococcus spp. (13.6%), and Enterococcus spp. (13.3%). In vitro susceptibility among all isolates varied for commonly prescribed antimicrobials (amoxicillin [59%], amoxicillin/clavulanic acid [76%], cephalexin [66%], enrofloxacin [74%] and trimethoprim‐sulfamethoxazole [86%]). For all antimicrobials tested (except aminoglycosides), in vitro susceptibility was higher in uncomplicated versus complicated infections (P < .05). Uncomplicated infection isolate susceptibility rates remained ≤90% for PO administered antimicrobials. Administration of amoxicillin, doxycycline, and enrofloxacin, but not amoxicillin/clavulanic acid in the previous 30 days was associated with resistance to that antimicrobial. Multidrug resistant isolates of E. coli and Staphylococcus spp. were more common in dogs with complicated than uncomplicated UTIs (36% versus 21%, P < .0001).Conclusions and Clinical ImportanceIn vitro susceptibility was highly variable and no PO administered antimicrobial had >90% efficacy among isolates tested. Multidrug resistance was frequent among isolates tested suggesting that routine culture and susceptibility testing is indicated. Previously prescribed antimicrobials may affect empirical choices made pending susceptibility testing.

Update on Urinary Tract Infections in Dogs in a Tropical Island and Antimicrobial Susceptibility of Escherichia Coli Isolates for the Period 2010-2016

“…These findings are in agreement with the observation that UTIs in dogs are generally caused by a single bacterial species, the predominant being E. coli. 15 Several recent studies on UTI in dogs in temperate countries [6][7][8][9] have shown that E. coli is the predominant cause of UTI as seen in the present study and our previous study for the period of 2004-2009 in Grenada. 10 UTI is more common in female dogs, which is in agreement with the results of the previous study in Grenada.…”

“…5 In a study in the U.S, over 80% of urinary tract isolates were found to be susceptible to enrofloxacin. 5 Despite several recent publications on bacterial UTI in dogs from Europe and the United States, [6][7][8][9] there is scanty information from tropical areas. The results of a study on the canine urine samples from cases suspected of UTI in Grenada, a tropical Caribbean island nation during the period of 2004 to 2009 were published recently by Hariharan et al 10 E. coli was the predominant species associated with UTI, followed by Proteus mirabilis and Staphylococcus intermedius/Staphylococcus pseudintermedius.…”

Antimicrobial Resistance & ‘Man's best Friend’: What they give to us we might be giving Right Back

“…Drugresistant pathogens have been documented in animals as they have in humans. For example, Wong et al reported on susceptibility of bacterial pathogens causing urinary tract infections in dogs with data collected between 2010 and 2013 [17]. Multidrug-resistant E. coli strains were found more commonly in complicated UTI than in uncomplicated cases.…”

Preventing canine urinary tract infection (UTI) using an asymptomatic bacteriuria (ASB) Escherichia coli strain

“…Many reports have shown that bacterial UTI are more common in older female dogs, indicating that this is an important risk factor (Kivisto et al, 1977;Bush et al, 1978;Thomsen et al, 1986;Cavana et al, 2008;Sidjabat et al, 2009;Hall et al, 2013;Wong et al, 2015). The mean age at diagnosis regardless of sex is approximately 7-8 years (Ling et al, 2001;Cohn et al, 2003).…”

“…In addition, persistent and recurrent urinary tract infections are regularly diagnosed in small animal referral practice (Norris et al, 2000;Seguin et al, 2003). Norris et al (2000) suggested that recurrent or persistent UTI are present in up to 4.5% of dogs with UTI or 0.3% of the canine hospital population, and recurrent or persistent UTI was identified in 27.1% of dogs included in a recent study reporting on urinary bacterial isolates from dogs presenting to a veterinary teaching hospital (Wong et al, 2015). Whilst the conventional view has been that the majority of bacterial cystitis episodes resolve with a 7-14 day course of oral antimicrobials, it is now apparent that assumption of microbiologic cure may be ill advised.…”