Lower urinary tract infection, feline idiopathic/interstitial cystitis Flashcards
(39 cards)
Lower urinary tract infection is usually caused by
E.coli bacteria. Infecting bacteria typically originate from the enteric flora and ascend through the distal urogenital tract into the proximal urethra and urinary bladder.
Other organisms like fungi account for only ∼1% of dog and cat bladder infections.
Lower urinary tract infection leads to bacterial…
cystitis.
Meaning infection causes inflammation (cystitis) followed by clinical signs.
- Caudal abdominal pain, pollakiuria, stranguria, dysuria
Difference between pollakiuria, stranguria, dysuria.
Pollakiuria = Increased frequency of urination with normal or low volume.
Stranguria = Slow, painful, dribbling urination, often due to blockage.
Dysuria = General pain or discomfort during urination, often a burning sensation.
Each symptom may overlap with others but points toward different underlying issues in the urinary tract.
Lower urinary tract infection typical patient signalment.
Spayed female dogs (2x higher risk compared to males)
Dogs>cats
the gold standard for identifying bacteriuria
Quantitative aerobic culture from aseptic cystocentesis.
However, the lower urinary tract is not a sterile environment, and the microbiological documentation of bacteriuria is not equivalent to diagnosing a UTI.
Potentially benign explanations for detecting bacteriuria include technical errors, sample contamination, and subclinical bacteriuria.from
diagnostic cut-off for non-contaminant bacteriuria
Using >100,000 colony-forming units/mL as a diagnostic cut-off, voided urine samples have a 94% sensitivity and specificity for non-contaminant bacteriuria.
Subclinical bacteriuria Treatment
not recommended, assess patient (comorbidities?) and bacteria.
Untreated: monitor clinical signs, urine (blood, protein, inflammatory cells)
Diagnosis of Lower urinary tract infection includes:
Bacteriuria + cystitis
Interpret together: clinical signs, urinalysis, urine sediment examination, aerobic urine culture
The standard therapy for UTIs is
antimicrobials.
Therapeutic plans vary depending on previous UTI history (sporadic vs persistent reinfeciton), concurrent diseases, neutering status, sex, and species.
Broadly, treatment strategies for UTI fall into 2 categories, depending on whether bacterial cystitis is sporadic or recurrent.
Sporadic bacterial cystitis is defined as
a clinical bladder infection occurring <3 times in a 12-month period, regardless of the patient’s species, sex, neuter status or co-morbidities.
Treatment of sporadic bacterial cystitis.
Empiric in dogs with limited previous antibiotic therapy but Urine culture and sensitivity still recommended, especially in cats.
Consider local resistance patterns, urine antibiotic concentrations, adverse effects, cost.
Typically used:
Amoxicillin, cephalexin, trimethoprim-sulfonamide
Duration of treatment 3-5 days
NSAID While waiting for culture and sensitivity results in an otherwise healthy dog.
Recurrent bacterial cystitis or recurrent UTI is said to be present when…?
Recurrent infections indicate that…?
Recurrent bacterial cystitis or recurrent UTI is said to be present when a dog or cat has 3 or more documented clinical infections within 12 months.
Recurrent infections indicate that an underlying anatomic, functional, or metabolic abnormality or comorbidity is present, either preventing the clearance of an infection (persistence and relapse) or allowing for reinfection.
Persistent infections occur when appropriate antimicrobial therapy fails to sterilize the urine.
Treatment of persistent bacterial cystitis.
If Systemic disease (immune, GI, hepatic, renal) - MUC/mean urinary concentration of AB ↓
- Treat dz if possible
- If Not possible to treat: antibiotic dose adjustment/alternative antibiotic.
If Resistant UTI
- High-dose amoxicillin/clavulanic acid
- Directly instilling aminoglycoside antibiotics into the bladder.
If Encrusted cystitis e.g. Corynebacterium urealyticum
- Antibiotic + urine acidification + surgical debridement
A relapsed UTI differs from a persistent infection in that during relapse,
urine can be cleared of infection but bacterial reservoirs remain.
These allow for urine recolonization with the same organism within a few days to weeks.
Sites that may harbor bacterial colonies include the kidneys, prostate, uroliths, vagina, urothelial cells.
Treatment of relapsed UTI.
Identify the site of infection and eradicate bacterial reservoir.
longer AB course - 7-14 d to 4-6 w
Reinfection occurs when
there is an alteration to host defenses that allow new bacterial strains to colonize the urinary bladder weeks to months after an initial UTI.
In both reinfection and relapse, a time period exists when the patient’s urine is sterile.
This makes it challenging to differentiate between the two when similar bacterial species are isolated in subsequent infections.
Prevention of urinary tract infections. (2)
Adherence blockade
- Cranberries and proanthocyanidins (PAC)
- D-mannose
- Glycosaminoglycans (GAGs)
Bacterial interference
- Probiotics - intravesical/oral/vaginal
Adherence blockade options for LUT infections? (3)
- Cranberry and proanthocyanidins (PAC)
- D-mannose
- Glycosaminoglycans (GAGs)
How does cranberry help toward UTIs?
Pproanthocyanidins/PACs in cranberries have anti-biofilm properties and can prevent pyelonephritis-inducing P-fimbriated uropathogenic E. coli from binding to uroepithelial cells.
In dogs, PAC consumption reduces E. coli adherence in vitro but evidence of an in vivo clinical benefit is actually lacking.
How does D-mannose help toward UTIs?
D-mannose aims to disrupt bacterial adhesion to the urothelium by blocking the ability of lectins on the tips of type 1 fimbriae to interact with carbohydrate moieties located on urothelial cells.
Several rodent studies have demonstrated decreased uropathogenic E. coli colonization after incubation of bacteria with D-mannose, although it is unclear whether oral administration of D-mannose achieves urinary concentrations sufficient to provide a clinical benefit in dogs and cats.
How do Glycosaminoglycans/GAG help toward UTIs?
GAG therapy theorizes that exogenously administered GAG may augment the urothelial GAG layer or bind to invading bacteria, preventing bacteria-induced injury.
In people, several independent studies have demonstrated that direct instillation of the GAGs hyaluronic acid and chondroitin sulfate into the urinary bladder reduces UTI recurrence rates.
In veterinary medicine, the efficacy of GAG bladder instillations to prevent UTI remains unproven.
What’s the idea behind probiotics helping combat UTIs?
The idea is Bacterial interference.
In people with disorders of urine retention causing reinfection, instilling the ASB strain E. coli 83972 into the urinary bladder reduced reinfection by up to 50%. In dogs, intravesical instillation of a similar biotherapeutic, E. coli 2-12, also resulted in near clinical cure in 4 of 9 dogs by day 14.
Probiotics may also be used for altering the urinary microenvironment and to decrease the vaginal pH, thereby inhibiting uropathogenic bacterial colonization.
In people, oral and vaginal administration of Lactobacillus has been shown to effectively increase the population of lactic acid producing bacteria within the vagina, reduce the number of uropathogenic bacteria isolated, and reduce the recurrence of UTI.
The most common cause of chronic lower urinary tract signs in cats?
+ Etiopathogenesis?
Feline idiopathic/interstitial cystitis
Etiopathogenesis:
Persistent activation of the central threat response system →
persistent activity in nervous, endocrine, immune systems
→ changes in behavior, bladder, skin, GIT, other organ function.
Genetic, epigenetic, environmental factors.
Recurrence common, cannot be assumed to result from the same etiology.
Clinical signs of FIC.
Intermittent, wax and wane, triggered by stressful situations.
LUTS signs:
Dysuria
Stranguria
Pollakiuria
Hematuria
Periuria (house soiling)
Other signs associated with stress:
Overgrooming
Hiding
Biting, scratching