Page 525 - WSAVA2017
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T.M. Sørensen1
1University of Copenhagen, Dept Vet Clin Scien, Frederiksberg, Denmark
Lisbeth Rem Jessen, DVM, Dipl. ECVIM-CA (lrmj@sund.
Tina Møller Sørensen, DVM, PhD student (
University of Copenhagen, Dept. of Veterinary Clinical Sciences, Dyrlægevej 16
Dogs with clinical signs of lower urinary tract disease are commonly encountered in veterinary practice, and UTI is a common indication for antibiotic prescription. Clinical signs of lower urinary tract disease are characteristic, but unspecific for infection and the prevalence of cystitis in dogs with compatible clinical signs is reportedly around 50 % (1, 2). Only dogs with bacterial infection (cystitis) will benefit from antimicrobial treatment and rational clinical decision-making is therefore a prerequisite to ensure proper case management and prudent use of antibiotics.
Clinical decision-making can be divided in two phases; (i) the decision to treat with an antimicrobial and the (ii) choice of antimicrobial class (drug-dose- duration)
Several studies have investigated the sensitivity and specificity of available point-of-care diagnostic tests (table 1) for identification of clinically relevant bacterial growth (significant bacteriuria). The studies were performed in tertiary facilities or university settings, and results are therefore not necessarily representative of the accuracy obtained in veterinary primary practice.
Table 1:Accuracy of currently available point-of- care diagnostic tests.
Quantitative bacterial culture (QBC) is still the gold standard for diagnosing UTI, although new and faster
methods to discriminate cases with and without infection are emerging (3). When performed by trained personnel, microscopy of stained sediment can be a useful point- of-care test and is recommended along with bacterial culture to diagnose sporadic cystitis in dogs (4, 5). Complete urinalysis is part of the standard diagnostic work up and can provide information with regard to underlying or concomitant disease processes.
The purpose of susceptibility testing is dual; to target choice of treatment to the individual patient and to monitor susceptibility trends in practice. In areas of low resistance to first line agents, susceptibility testing of bacteria from first episodes of canine sporadic cystitis may be redundant, however regular susceptibility
testing of primary cases are necessary for surveillance
at practice level. In-house susceptibility testing is generally not adequate for surveillance purposes or for diagnostic work-up of recurrent cystitis or upper UTI. When applied for sporadic cystitis one must ensure use of validated point of care tests only, and performance of regular quality control. Susceptibility testing can easily be performed following in-house culture by sending swabs of colonies, or the entire agar plate, to a specialized laboratory.
Timing of treatment
Appropriate clinical decision making is not only dependent on accurate diagnostic tools, it also depends on timing. A recent prospective study in Denmark showed that 88% of dogs with clinical signs of UTI
were diagnosed with UTI according to the veterinarians, although only 49% of the dogs had significant bacteriuria on the gold standard QBC (2). As a consequence there was a high proportion of antibiotic over-prescription in dogs with suspected UTI. This resulted not only from lower accuracy of diagnostic tests when applied in practice, but mainly from a disconnection between test results and clinical decision making. In particular for bacterial culture, the decision to treat was made prior to reading of the test result. Preliminary results from an on- going randomized controlled diagnostic study suggest that use of point of care culture promotes appropriate antibiotic use if treatment is withheld for one day until test results are available.
Management of sporadic cystitis
Antimicrobial treatment of sporadic cystitis first of all aims at solving the clinical signs, more than completely eradicating the bacteriuria.
To avoid inappropriate overtreatment a “test – read – treat” strategy should be applied whenever possible. Withholding empiric antimicrobial treatment for 24 hours while awaiting the result of point of care culture is an
An Urban Experience

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