Equine: Alterations In Urinary Function.

Front 1

How often do horses urinate per day and in what volume? What is considered polyuria?

Back 1

Normal: 2-4 times per day.

10-30 ml/kg/day which is 5-15 litres

Polyuria: >50 ml/kg per day >25 litres

Front 2

How much do horses drink per day normally? What may alter a horses water intake? Polydipsia?

Back 2

50 ml/kg/day.

Temperature.

Feeding salt.

Water content of food.

Polydipsia: is >100 ml/kg/day.

Front 3

Common causes of PUPD?

Back 3

Primary/psycogenic polydipsia--> stabled and bored.

ECDz/PPID--> Aged, hirsute, lamitis, recurrent infections.

Primary Renal disease--> Aged, weight loss, uraemia.

Front 4

Less common reasons for horses developing PUPD?

Back 4

Pyschogenic salt consumption--> bored in stable.

Diabetes insipidus.

Drug induced/iatrogenic like corticosteroids or alpha adrenergic.

Front 5

How can we differentiate PUPD from pollakiuria?

Back 5

Monitoring water consumption.

Front 6

In terms of signalment what are the predispositions to different PUPD conditions?

Back 6

Age: Younger horses pyschogenic/primary polydipsia.

ECDz/PPID--> Older.

No sex or breed predispositions.

Front 7

What type of PUPD is common in stabled horses?

Back 7

Pyschogenic

Front 8

If we have PUPD with weight loss what diseases would you be suspicious of ?

Back 8

Chronic renal failure.

ECDz/ PPID.

Front 9

Diagnostic signs to look for when clinically examining a PUPD horse?

Back 9

PUPD vs Pollakiuria.

Hydration status.

Weight loss?

Any evidence of uraemia? Poor coat.

Ventral oedema.

Laminitis and hirsutism.

Front 10

What baseline tests should be run on a PUPD case?

Back 10

Urinalysis- SG, osmolarity, dipstick test, electrolytes and creatinine.

Haematology and biochemistry- WBC, urea and creatinine, PCV, Protein levels, electrolytes.

Glycaemic status.

Front 11

What are signs on haematology that may occur with kidney disease?

Back 11

Decreased RBCs.

Anaemia of chronic disease or decreased production of erythropoeitin.

Increased WBC due to chronic infections.

Front 12

What does increased urea and creatinine indicate in terms of urinary tract disease?

Back 12

>75% loss of total tubular function or dehydration.

Front 13

What may decreased protein reflect in terms of kidney disease?

Back 13

Glomerular mainly or tubular disease.

Front 14

What electrolyte parameters may indicate renal disease?

Back 14

Decreased sodium, chloride, potassium with acute or chronic renal failure.

Calcium increase with chronic and decrease with acute.

Phosphate decrease with chronic and increase with acute.

Front 15

If we have signs of renal disease what must we do in terms of further examination?

Back 15

Rectal examination--> evaluate kidneys and presence of pain.

Ultrasonography--> Size and echogenicity of kidneys.

Fractional excretion of electrolytes--> sodium.

Renal biopsy..Risk of fatal haemorrhage.

Front 16

If we have no sign of renal disease or cushings ruled out what can we do?

Back 16

Water deprivation test.

ADH stimulation test.

Front 17

What is the cause of PPID/ ECDz?

Back 17

Overproduction of proopiomelanocortin (POMC) peptides from the pars intermedia.

This leads to a increase in ACTH coupled with potentiated effects of other POMC peptides on ACTH leading to dysregulated cortisol secretion.

Front 18

What is found at PMI with most ECDz/PPID horses?

Back 18

Masses of the pituatary.

Front 19

Clinical signs of ECD?

Back 19

Hirsutism, hypertrichosis, change to coat.

Hyperhidrosis.

Laminitis.

Lethargy and poor demeanour.

Fat redistribution .

Predisposition to infetions.

Weight loss.

PUPD.

Polphagia.

Blindness.

Seizures.

Front 20

Why do we get hair coat changes with ECD?

Back 20

Increased cortisol may lead to increased androgen production.

Compression by growth on hypothalmic thermoregulatory centres.

Front 21

Why do we get hyperhidrosis with ECD?

Back 21

Effects of compression on hypothalmic thermoregulatory centres.

MSH involved in temp reg.

Front 22

Why do we get laminitis, fat redistribution and predisposition to infection with ECD?

Back 22

Effects of glucocorticoids on metabolism and immunity.

Front 23

What is pathognomonic for equine cushings?

Back 23

Hypertrichosis is the summer.

Front 24

What resting hormones can we use to help us diagnose equine cushings?

Back 24

Basal glucose >5.5 mmol/l

Basal insulin >36 iu/ml

Basal cortisol >140nmol/l

Basal ACTH over >27 pg/ml in ponies >50 pg/ml in horses.

Basal MSH >91 pmol/l

Front 25

What dynamic tests can we use to help us diagnose a horse with cushings?

Back 25

ACTH stimulation test--> poor sensitivity.

Dexamethasone suppression test overnight--> 50-100% specific and sensitive.

TRH response test.

Combine DST and TRH.

Front 26

What plays a role in the unreliability of diagnostic tests for equine cushings?

Back 26

Seasonality.

Increased false positives in the Autumn.

Front 27

How can we conservatively manage a cushings horse?

Back 27

1) Good attention to feeding, dentistry, antihelmintic regimes and early detection of clinical abnormalities.

2) Clipping excess long haircoat.

3) Regular farriery and monitor for signs of laminitis.

4) Continued exercise in absence of acute or chronic orthopaedic disease.

5) Monitor weight.

6) Treat infections promptly.

Front 28

What medications can we use to treat ECD?

Back 28

Pergolide a dopamine agonist that inhibits release of ACTH.

Cyproheptadine 5HT agonist inhibiting release of ACTH.

Trilostane 3beta HSD inhibitor.

Front 29

Poor prognostic indicators in a ECD horse?

Back 29

Intractable laminitis.

Weight loss.

Secondary diabetes mellitus.

Failure to respond to treatment.

Front 30

What are causes of urinary incontinence?

Back 30

Reflex/UMN bladder--> EHV-1, EPM

Paralytic/LMN bladder--> Polyneuritis equi, EHV-1, trauma.

Non neurogenic:

Inflammatory/irritant e.g. cystitis, urolithiasis.

Myogenic--> detrusor atony.

Neoplasia.

Mechanical--> breeding trauma, ectopic ureter.

Hypo-oestrogenism.

Front 31

In terms of signalment what are findings with incontinence?

Back 31

Age:Foals congenital like ectopic ureter. Neoplasia older.

Breed none.

Sex: Fillies predisposed to ectopic ureters and cystitis, mares breeding trauma.

Front 32

History and clinical signs of a horse with urinary incontinence?

Back 32

Continual dribbling of urine.

Moving/vocalising leading to urination due to increased abdominal pressure.

Urine smell.

Crystals and hair loss on perineum, sheath, hindlimbs.

Ataxia, caudal neurological deficits--> LMN, tail tone poor, anus, sensation.

Front 33

Further investigations we can undertake in a incontinence case?

Back 33

Urinalysis.

Vaginal exam.

Ultrasound.

Cystoscopy.

Cystometry.

Front 34

How can we treat incontinence?

Back 34

Palliative care like drainage and flushing.

Washing and then vaseline.

Antibiotics.

Some mares respond to antibiotics.

A adrenergic blockers to decrease sphincter tone to allow urination with UMN.

Bethanecol for detrusor function.

Front 35

Define uraemia?

Back 35

Clinical signs associated with increase nitrogenous compounds in bloodstream such as anorexia, weight loss, bedraggled hair coat.

Front 36

Define azotaemia?

Back 36

Abnormal increase in biochemical parameters associated with renal disease.

Pre-renal: decreased renal perfusion due to dehydration.

Renal: Acute/chronic renal failure.

Post-renal azotaemia: Obstructive disorder.

Uroperitoneum.

Front 37

When does renal failure occur in the horse?

Back 37

Loss of 75% of nephrons.

Front 38

What crystal is common in horse urine and why?

Back 38

Calcium carbonate as excrete lots of calcium through their kidneys.

Front 39

Causes of ACUTE renal failure in horses?

Back 39

Acute tubular necrosis: Drugs (NSAIDs, aminoglycosides,polymixin B), heavy metals, pigments, acorns, vitamins D and K3.

Vascular: vasomotor neuropathy: dehydration, shock, hypotension, adverse reaction.

Acute glomeruloneuropathy--> immune mediated

Acute interstital nephritis.

Leptospirosis.

Front 40

DDX for chronic Chronic renal failure in horses?

Back 40

Glomerular disease.

Chronic interstitial nephritis.

End stage kidney disease.

Amyloidosis.

Neoplasia.

Front 41

Signalment findings with renal failure patients?

Back 41

Age: Older or very young due to congenital.

Breed none.

Sex: males predisposed to bladder rupture and females ectopic ureter.

Front 42

History and clinical exam findings with kidney failure?

Back 42

Depression.

Anorexia.

Dysuria that is isosthenuric.

Front 43

Normal USG of horse? Iso? Hypos?

Back 43

USG normally 1.020-1.050

Iso 1.008-1.014

Hypo <1.008

Front 44

Normal dipstick findings on horse urine?

Back 44

pH- 7-9

Protein +1

Glucose none

Ketones none.

Hb/Mb none.

Bilirubin None

Front 45

What tests would we run for a horse in kidney failure?

Back 45

Haematology (Anaemia) and biochemistry( Urea/creatinine, electrolytes.

Urinalysis- Isosthenuria, increased urinary enzymes, haematuria, increase casts.

Front 46

Other tests we can run with a renal failure case?

Back 46

Ultrasound.

Endoscopy.

Fractional excretion of electrolytes.

Measure GFR.

Biopsy.

Front 47

How do we treat acute renal failure?

Back 47

1) Fluid therapy with regular monitoring of electrolyte status. Be careful not to overhydrate and for oedema formation.

2) Monitor urination. If oliguric after 24 hours address with furosemide, mannitol, dopamine.

3) Peritoneal dialysis.

4) Creatinine should decrease by at least 30% in 24 hours.

5) Slowly wean off fluids and supplement electrolytes short term.

Front 48

Approach to treating a chronic renal failure case?

Back 48

1) Fluids for 24-48 hours

2) Identify and treat abnormality.

3) Diet- correct electrolyte and acid/base abnormalities, small and frequent meals, avoid high calcium feeds like alfalfa, increase cards, anabolic steroids.

4) Blood/plasma transfusion for anaemia etc.

5) Erythropoeitin.

Front 49

DDX list for haematuria?

Back 49

Urethral tear.

Cystitis/UTI/Urolithiasis.

Idiopathic renal haematuria-> arabs

Neoplasia.

Drugs.

Vaginal varicosities--> multiparous mares.

Exercise induced haematuria.

Non specific urinary disease like haemolysis, acute myopathies and coagulopathies.

Front 50

How do we differentiate haematuria from haemoglobinuria or myo?

Back 50

Small amounts scattered on dipstick is blood.

Microscopic exam for cells.

Spin down urine and look for pellet of sells.

Front 51

How do we differentiate glomerular from non glomerular bleeding?

Back 51

Evaluate the morphology of cells. More variable appearance with glomerular disease.

HB casts.

Front 52

How does evaluating timing of haematuria help us tell where it is coming from?

Back 52

Throughout urination: kidneys, ureters, bladder.

Beginning of urination: distal urethra.

End : Proximal urethra and bladder neck.

Front 53

On haematology and biochemistry what would we do with a case of haematuria?

Back 53

Any evidence of haemolysis on PCV.

Muscle disease--> CK, AST.

Coagulation parameters.