Urinary Tract Infections

Flashcards about urinary tract infections in dogs and cats

UTI

A common cause of lower urinary tract disease (LUTD) in dogs (14%) but uncommon in cats (1-3%). It isn't synonymous for bladder infection, and may involve kidneys, ureters, bladder, urethra, prostate.

Ascending Infection

The primary route of infection in the urinary tract, requiring adherence and colonization.

Bacterial virulence factors

Motility, adherence, toxin production, iron acquisition, and immune evasion.

Anatomic barriers against UTI

Urethral length, urethral high pressure zone, and urothelium.

Mucosal Barriers against UTI

Glycosaminoglycans, Immunoglobulin production, Cell exfoliation, and Commensal bacteria.

Lower urinary tract clinical signs that could indicate infection

Pollakiuria, Stranguria, Hematuria, Strong odor

Upper urinary tract clinical signs that could indicate infection

Anorexia, lethargy, back pain, PU/PD (chronic)

CBC results to indicate UTI

Normal / “Stress” leukogram or Leukocytosis

Urinalysis components for UTI diagnosis

Bacteria, specific gravity, and casts.

Preferred method for urine collection for culture and sensitivity

Cystocentesis

Imaging techniques to assess UTIs

Radiographs, Ultrasound, and Excretory urogram (EU, IVP)

Sporadic bacterial cystitis (aka “uncomplicated cystitis”)

No predisposing factors found, normal anatomy, no neurological deficits, no immune-suppressive diseases or medications, “Typical” lower UTI clinical signs, and < 3 episodes/year

“Complicated” UTI

Identifiable predisposing factors, Ectopic ureters, Neurologic disease, Hyperadrenocorticism, Neoplasia, and Immune-suppressive medications

Subclinical bacteriuria

Positive culture w/o clinical signs

Recommended duration of antibiotic treatment for uncomplicated (sporadic) bacterial cystitis

3-5 days

Persistence in UTI treatment

Failure to eradicate organisms, demonstrated by positive culture 3-5 days after initiation of antibiotic therapy (same strain)

Relapse in UTI treatment

Positive culture ~5-7 days after discontinuation of antibiotics with same strain

Reinfection in UTI treatment

Culture different organism

Methenamine hippurate

Urinary antiseptic that is converted to formaldehyde and requires acidic urine (pH < 6)

Treating first-time uncomplicated infection

Pick ONE drug (see notes or ISCAID guidelines for bacterial UTI’s – 2019), treat for 3-5 days, and culture if clinical signs persist >3 days, or if rapid recurrence