urinary 2 Flashcards
routes of infection for UTI - which are common
- Ascending – most common
- Descending (hematogenous) – less common
Urinary Tract Infections
* pathogenesis depends on what? what are some common possibilities?
- Type of bacteria, virulence factors, quantity of “inoculated” bacteria, source of bacteria & other factors, such as trauma.
- Trauma: difficult calving, obstetrical manipulations or catheterization
- Bladder dysfunction may lead to reflux into the ureters, causing ascending spread of bacteria and infection. Vulvar conformation, pneumovagina and metritis are important factors.
Bacteria commonly implicated in bovine UTI – ascending infections
- Corynebacterium renale
- Escherichia coli
- Other Enterobactericae
- Other Corynebacterium spp.
Bacteria commonly implicated in bovine UTI – descending infections
- Salmonella species
- Trueperella pyogenes
- Corynebacterium pseudotuberculosis (sheep & goats)
Corynebacterium renale
- characteristics
- survival in environment
- virulence factor important for UTI, and other factors
- transmission
- occurence
- eradication
- Gram-positive, club-shaped bacterium
- Adapted to the bovine and ovine urinary tract
- Thought to survive for a short period in the environment
- Pili which attach to the urinary or vaginal epithelium is a virulence factor
- Attachment is enhanced in an alkaline environment and inhibited in an acidic environment.
- Cattle & sheep can be carriers & cause horizontal spread
- Venereal and iatrogenic spread also occur
- Occurrence not as often these days due to decreased bladder catheterization by veterinarians!
- Very difficult to eradicate once the organism becomes established on a farm
cystitis clinical signs
- Pollakiuria, dysuria
- Agitation - treading, twitching tail
- Thickened bladder on rectal examination
- Abnormal urine - red, yellow, white (although may appear normal)
- Systemic signs of disease usually not apparent (ie. fever, inappetance)
pyelonephritis clinical signs
- Fever, depression, inappetance, decreased milk production
- Mild colic
- Other signs as for cystitis
- Rectal examination - left kidney - painful to palpation, loss of lobulation
- Ultrasound examination - enlarged kidney, loss of lobulation, abnormal shape, enlarged calyces, presence of echogenic, flocculent material.
- NB: chronic disease - signs are vague
UTI - Differential Diagnosis
- Gastrointestinal disease - causing colic (normal urinalysis)
- Urolithiasis
- Trauma
- Vaginitis or perivaginal abscesses
- Enzootic hematuria (access to bracken fern, anemia, lack of pyuria, bacteriuria)
UTI - Dx and Treatment
- Gram-stain
- Bacterial culture & antibiotic sensitivity
- Repeat 1 week after therapy is finished.
- C. renale: high doses of penicillin or ampicillin for
at least 3 weeks - E. coli and other coliforms - penicillin, ampicillin, ceftiofur, trimethoprim sulfonamide
- Adequate withdrawal times
UTI - Prognosis
Depends on severity & duration of disease
* Levels of tract affected
* Unilateral or bilateral
* Antimicrobial sensitivity
* Azotemia will decrease prognosis
* Case fatality and culling: 18 - 33% of treated cases (however many variables)
Acute Tubular Necrosis
- causes
Altered perfusion
* Hypovolemia
* Disseminated intravascular coagulation
* Renal vein thrombosis
Acute Tubular Necrosis common causes
- Antibiotics
- Metals
- Plants
- Endogenous compounds
- Other exogenous compounds
antibiotics implicated in acute tubular necrosis
- Aminoglycosides > Neomycin, Gentamicin, Amikacin
- Tetracyclines
- Sulfonamides
metals implicated in acute tubular necrosis
- Arsenic
- Mercury
- Lead
- Cadmium
plants implicated in actute tubular necrosis
- Quercus (oak)
- Amaranthus species
- Rumex spp.