Acute kidneys injury, Urinary tract infections

Question 1

What can cause acute kidney injury?

Answer 1

• Decreased renal blood flow
• Toxins = Antibacterials (aminoglycosides), NSAIDs, Ethylene glycol, lilies(cat), Grapes(dog), others
• Intrinsic renal diseases = leptospirosis, pyelonephritis
• Systemic diseases

Question 2

What is the pathophysiology of AKI? (4 stages)

Answer 2

• Initiation phase = damage start (no CS)
• Extension phase = ischaemia, hypoxia, inflammatory response, ongoing cellular injury, cell death (maybe no CS)
• Maintenance phase = stabilisation of GFR,
  -typically see azotaemia, uraemia, variable urine production
• Recovery phase = azotaemia improves + tubules undergo repair, can have marked polyuria during this stage

Question 3

What history is needed for recognising AKI?

Answer 3

• Recent onset of anorexia, polydipsia, vomiting
• May get CNS signs in ethylene glycol ingestion
• Toxin exposure/ nephrotoxic drugs?
• Ischaemic episode?
• Vaccination status? – Leptospirosis

Question 4

What is seen on physical exam with AKI?

Answer 4

• Uraemic breath
• Hypothermia (unless infection)
  ± Kidney pain or enlargement
• Tachycardia - dehydration, pain
• Bradycardia - hyperkalaemia

Question 5

How would you diagnose AKI?

Answer 5

• HX + CS
• Blood sample = azotaemia, hyperphos, hyperkalaemia
• Urine sample = isothenuric, look at sediment for casts, WBCs, bacteria + crystals

Question 6

What are differences between AKI + CKD?

Answer 6

• AKI =
  -Good BCS
  -Acute onset
  -+/-history of toxin exposure
  -Kidneys may be enlarged / painful
  -May be disproportionately sick for degree of azotaemia
  -+/-hyperkalaemia
  -Urine sediment may show casts
  -Good hair coat
• CKD =
  -Weight loss
  -Previous history of PUPD/poor appetite/ GI signs
  -non-regenerative anaemia
  -Kidneys small, firm/irregular
  -Often well for degree of azotaemia
  -Normal / low potassium
  -poor hair coat

Question 7

If a dog is hypotensive for several minutes under GA, what does it indicate?

Answer 7

• Acute kidney injury

Question 8

How can you treat specific cause?

Answer 8

• Induce vomiting if recent toxic ingestion
• Give ABs if leptospirosis suspected ( or until pyelonephritis ruled out)

Question 9

How do you manage AKI?

Answer 9

1. specific Tx to eliminate cause
2. Supportive tx = IVFT (based on degree of hydration)
   -don’t flush kidneys, give excess fluid (overload failing kidney)

Question 10

How would you manage anuria / oliguria?

Answer 10

• Rehydrate - if urine flow <2ml/Kg/hr = oliguria =
  -reassess hydration ,BP
  -Reduce IVFT
  -Place urinary catheter
  -Start Tx to increase urine output (furosemide)

Question 11

How can you treat other problems related to AKI?
(vomiting,hypertension, nutrition)

Answer 11

• Vomiting = maropitant
• Hypertension = reduce IVFT, give diuretics
• Nutrition = AKI = highly catabolic disease

Question 12

What should be done if renal function worsens, fails to improve, or does not improve sufficiently for animal to be managed medically?

Answer 12

• Dialysis - RVC
• Euthanasia

Question 13

What pets are predisposed for urinary tract infections?

Answer 13

• Female > Male
• Dogs > Cats

Question 14

What are different UTIs in dogs / cats?

Answer 14

• Sporadic bacterial cystitis
• Recurrent bacterial cystitis
• Pyelonephritis
• Bacterial prostatitis
• Sub clinical bacteriuria

Question 15

What are clinical findings with UTIs?

Answer 15

• Cystitis = dysuria, pollakiuria, haematuria + urinary incontinence
• Pyelonephritis = abdominal pain, AKI, septicaemia
  -+/- PUPD
• Bloods = lower UTI = no changes
  -Upper UTI = bloods consistent with septicaemia / AKI

Question 16

How are UTIs diagnosed?

Answer 16

• Urinalysis
• Urine sediment examination (WBC + bacteria)
• Urine culture (cystocentesis = best)

Question 17

How are different uti’s treated?

Answer 17

• Sporadic bacterial cystitis = ABs 3-5d, NSAIDs, amoxicillin, cephalexin / trimethoprim
• Recurrent bacterial cystitis = look for predisposing factors
  -treat for 3-5d, longer if impaired response
• Pyelonephritis = treat for 10-14d
• Bacterial prostatitis = Ab that penetrates blood-prostate-barrier (sulphonamide/fluoroquinoloes) - Tx = 4wks
• Subclinical bacteriuria = no Tx

Question 18

If an entire male has an UTI what would you assume?

Answer 18

• Bacterial prostatitis

Question 19

Is it normal for dogs to have bilirubin in their urine?

Answer 19

• Normal in dogs
• Abnormal in cats