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128 Urinary Tract Infections 1195

VetBooks.ir Box 128.1 Ideal steps to follow in the management of UTIs in dogs and cats
1) Diagnosis should be determined on the basis of his-
4) Examine urine sediment 3–4 days before discontinuing
tory, urine sediment, and, ideally, urine culture and
antibiotic treatment.
sensitivity results. Rule out contamination in voided/ 5) Repeat urinalysis and culture 5–7 days after cessation of
catheterized samples with quantitative culture. antibiotic therapy. (Steps 4 and 5 are especially impor-
Cystocentesis is the ideal way to collect urine for culture. tant for recurrent UTI.)
2) Select an antimicrobial agent based on culture and sen- 6) Patients with recurrent UTIs should undergo imaging
sitivity. Without culture and sensitivity results, use air‐ studies (e.g., plain and/or contrast‐enhanced radiography
dried sediment findings to guide antibiotic choice (e.g., and/or ultrasonography), a complete blood count, and
cocci vs rods). serum biochemistry profile to determine whether they
3) Reculture urine (or at least examine the urine sediment) have local/systemic underlying predisposing factors.
in 3–5 days to ascertain effectiveness of selected antimi- 7) Frequent reinfections may need to be treated with low‐
crobial agent. Urine culture should be negative and/or dose nighttime antibiotic regimes or cranberry extract
there should be no white blood cells in the urine after the initial inflammation has been cleared up in
sediment. response to standard‐dose antibiotic treatment.

Box 128.2 Reasons for poor therapeutic response in dogs and cats with UTI

Use of ineffective drugs or ineffective duration of therapy an inaccessible site (e.g., prostate, neoplasia, or
●
(relapse). uroliths) (relapse).
Failure of owner to administer prescribed dose at proper Failure to recognize and eliminate predisposing causes
● ●
intervals (relapse). (reinfection).
Gastrointestinal tract disease, concurrent intake of food Presence of mixed bacterial infections in which only one
● ●
and drug resulting in decreased drug absorption, or of the pathogens is eradicated by antimicrobial therapy
impaired renal concentrating ability resulting in decreased (relapse).
antibiotic concentrations in the urine (relapse). ● Iatrogenic reinfection caused by catheterization
Impaired action of drugs, either because bacteria are (reinfection)
●
not multiplying or because they are sequestered in ● Development of drug resistance in bacteria (relapse).

Prognosis tance to correct underlying defects in host defenses
whenever possible to achieve the best outcome with a
Most UTIs are uncomplicated and appropriate antibiotic complicated UTI. Following protocols for ideal UTI
treatment rapidly clears the infection, resulting in a management and monitoring will improve treatment
good prognosis. However, the prognosis for a compli- success and decrease the incidence of recurrent UTI
cated UTI may be guarded. It is of the utmost impor- (Boxes 128.1 and 128.2).