Endocrine/metabolic snd urinary Flashcards
What biochemistry markers can affect calcium values?
Low albumin - lowers calcium
Elevated phosphate increased complexed fraction of calcium.
The results of FGF-23, decreased calcitriol and reduced calcium absorption:
Increased PTH
Mineralisation in soft tissues including kidney and gastric mucosa
What are the causes of hypercalcaemia in dogs?
Increased PTH activity
Activity of PTH-like substances
Increased vitamin D activity
Osteolysis
Others - hypoadrenocorticism, raisin toxin, idiopathic
Can hypoadrenocorticism cause high or low calcium levels?
Normally mild hypercalcaemia - total calcium
What specific marker is excellent indicator of dietary sufficiency and excess?
25 hydroxy-vitamin D
What marker is implicated in the pathogenesis of renal secondary hyperPTH if low?
1, 25 dihydroxy-vitamin D
What are the general steps to treating hypercalcaemia?
Determine urgency by Ca x P
Fluids, diuresis
Glucocorticoids
Bisphosphonates
What is the short term therapy for hypocalcaemia?
IV calcium and monitor for bradycardia
What are the aims for long term therapy of hypocalcaemia
Aim for subclinical or low/normal hypocalcaemia
Oral calcium supplement if diet insufficient
Vitamin D to promote calcium uptake
What are the clinical signs of diabetic ketoacidosis (DKA)?
Inappetence/nausea/vomiting
Reduced mentation
Hypoperfusion and dehydration
Death
What is the summarised pathophysiology of diabetes ketoacidosis?
Reduced insulin causes a metabolic deficit of glucose. This causes the body to metabolise fatty acids into ketones instead, causing metabolic acidosis.
What findings usually accompany diabetes ketoacidosis?
Anaemia and left shift neutrophilia
Elevated ALP and ALT
Electrolyte derangements
Bacteriuria
What are the general steps to treating diabetes ketoacidosis?
Hartmann’s IVFT
Potassium supplement - monitor
Then achieve normoglycaemia
What is the prognosis for diabetes ketoacidosis?
Good - 70% however risk of relapse
What is hyperglycaemic hyperosmolar syndrome?
Similar to DKA but with a small amount of insulin and glucagon resistance. Reduces lipolysis so ketones aren’t elevated.
What is key with the treatment of hyperglycaemic hyperosmolar syndrome?
Fluid therapies are key however do it slowly to prevent risk of seizures, coma and death. Aim to restore normoglycaemia over 24-48 hours.
Are cases of hyperadrenocorticism more likely to be pituitary or adrenal dependant?
80-90% are pituitary dependant
What are the presenting signs of hyperadrenocorticism?
Middle aged - old female dogs
PU/PD, polyphagia
Muscle wasting and weakness
Skin thinning, calcinosis, pigmentation, bruising
Symmetrical alopecia, reproductive dysfunction.
What are the key diagnostics for hyperadrenocorticism?
Low dose dexamethasone or ACTH stim test
Haematology and biochemistry
Urinalysis
What does the low-dose dexamethasone test aim to show?
Resistance of abnormal pituitary-adrenal axis to suppression by dexamethasone.
What does the ACTH stim test measure?
Measure of adrenocortical reserves
When should urine be collected to measure urinary cortisol/creatinine levels?
One or more morning samples at home in a non-stressed environment
What are the advantages of the low-dose dexamethasone test?
Highly sensitive and may differentiate as well as diagnose
What are the disadvantages of the low-dose dexamethasone test?
Long test (8hrs), poor specificity, non appropriate if a history of exogenous steroids.
What are the advantages of the ACTH stim test?
Short (1hr), more specific, used to monitor trilostane
What are the disadvantages of the ACTH stim test?
Less sensitive, cannot provide differentiation
What are the advantages of the urinary cortisol/creatinine test?
Inexpensive, convenient for owner, highly sensitive
What are the disadvantages of the urinary cortisol/creatinine test?
Very poor specificity
What medical treatments are there for hyperadrenocorticism?
Trilostane (licenced), mitotane, selegilne
What are the clinical signs and findings for phaeochromocytoma?
Pu/PD, panting, weakness, weight loss, hypertension, poor appetite
Adrenal mass, hyperglycaemia
What values of urine indicate polyuria?
> 50ml/kg/day of urine
What values of water intake indicate polydipsia?
> 100ml/kg/day (dogs), >50ml/kg/day (cats)
When should urine be collected to measure urine cortisol/creatinine?
One or more sample in the morning at home in a non-stressful environment.
What are the advantages of the low dose dexamethasone test?
Highly sensitive, may differentiate as well as diagnose
What are the disadvantages of the low dose dexamethasone test?
Long test (8 hours)
Poor specificity
What are the advantages of the ACTH stimulation test?
Short test (1 hour)
More specific than LDDST
More confidence in positive result
What are the disadvantages of the ACTH stimulation test?
Less sensitive than LDDST
Cannot provide differentiation
What are the advantages of the urinary cortisol creatine test?
Inexpensive
Convenient for owner
Highly sensitive
What are the disadvantages of the urinary cortisol creatinine test?
Very poor specificity
What treatment is available for hyperadrenocorticism?
Trilostane (licenced), mitotane, selegiline
Adrenalectomy or hypophysectomy
What disease can be confused with Cushing’s?
Phaeochromocytoma
What are the clinical signs and findings of phaeochromocytoma?
PU/PD
Panting
Weight loss/poor appetite
Hypertension/ tachycardia
Adrenal mass
Hyperglycaemia
What values prove polyuria?
> 50ml/kg/day of urine
What values prove polydipsia?
> 100ml/kg/day intake (dogs)
50ml/kg/day (cats)
What can cause primary polydipsia?
Neoplasia, changes in osmolarity, endocrine disease, compensating other losses
Salt toxicity, exercise, high environmental temperature
What are some causes of primary polyuria?
Osmotic diuresis, medullary solute washout, Interstitial tonicity reduction, increased GFR
What is azotaemia?
Elevated urea and creatinine
What are the four phases of intrinsic acute kidney injuries?
- Asymptomatic phase of initial insult
- Hypoxia and inflammatory responses
- Increased or decreased urine output
- Recovery phase
What clinical signs can be seen with intrinsic acute kidney injury?
Signs associated with fluid loss
Concurrent illness, renal pain +/- palpable enlargement
Uremic halitosis, oral ulceration, jaundice
What are the results of leptospirosis infection?
Renal and hepatic damage
Dyspnoea
DIC
What is the most important treatment in an AKI
Fluid therapy - Hartmann’s
What treatment considerations are required for AKIs?
Suspected UTI - amoxiclav/doxycycline
Metabolic acidosis - Hartmann’s
Tachyarrhythmias - ECG and lidocaine
Hyperkalaemia - Glucose, insulin, bicarb
Hypertension - amlodipine
Nutrition - feeding tube
What are some causes of a blocked bladder?
Stone, stricture, inflammatory debris, UMN bladder, spasmodic
What can be found on the clinical exam of a blocked bladder?
Enlarged, pain, non-expressible
What is the common signalment for a blocked bladder?
Male animals - cats
Pugs, dalmations
What is the initial treatment for a blocked bladder?
Pain relief - methadone
What are the biggest worries with a blocked bladder?
Potassium causing bradycardia
Acidosis
Post-renal azotaemia/AKI
What medications should be used to sedate and place a catheter in an AKI?
Midazolam or diluted alfaxalone (1:4)
What are the three types of urinary catheter?
Jackson Tomcat
Slippery Sam
KatKath
What are the common presenting of chronic kidney disease?
PU/PD, pallor, anorexia, v+d, weight loss, mucosal ulcers, dehydration, uraemic breath
What co-morbidities can be associated with chronic kidney disease?
hyperthyroidism, heart disease, cystitis, diabetes
Previous AKI
Nephrotoxic drugs
What is an uraemic crisis?
Build up of urea and other toxins usually excreted in the kidneys to intolerable levels.
How do you treat chronic kidney disease?
IVFT
Treat nausea/GI ulceration
Antiemetics
Nutritional support
What is pyelonephritis?
Bacterial infection of the renal pelvis and parenchyma
What is polycystic kidney disease?
Fluid filled cysts present from birth in the kidney and possibly other organs
What is haematuria?
Red blood cells in urine
What is dysuria?
Difficulty or pain during urination
What can red urine indicate?
Blood and haemoglobin
What can orange urine indicate?
Strong urine
Bilirubin
What can brown urine indicate?
Myoglobin
Methaemoglobin
Copper toxicosis
Poo
What is the diagnostic approach to red or brown urine?
- Dipstick
- Sediment exam
- Haemoglobin/myoglobin
What is the diagnostic approach to orange urine?
- USG >1040
- Urine dipstick
- Blood biochemistry
What are the causes of myoglobinaemia?
Physical: Trauma, burns, strenuous exercise, prolonged immobility
Non-physical: Hypoxia, ischaemic, metabolic disturbances, infectious
What is stranguria?
Prolonged, painful straining
What is urge incontinence?
Involuntary bladder contractions voiding small amounts of urine regularly
What causes a big bladder?
Obstructive disease - detrusor atony, UMN, inflammatory, infectious, iatrogenic
What causes a small bladder?
Non-obstructive disease - anatomical, neuromuscular, inflammatory, infectious iatrogenic, idiopathic, FIC
What are the complications of urinary tract surgery?
Renal pain, haemorrhage, retroperitoneal and peritoneal urine leakage, UTI, compromise of renal function
How does the sympathetic nervous system affect the urinary tract?
Positive stimulus causes urethral smooth muscle contraction and inhibition of detrusor muscle allowing passive filling of the bladder
How does the somatic nervous system affect the urinary tract?
Stimulates urethral striated muscle contraction
How does the parasympathetic nervous system affect the urinary tract?
Stimulate detrusor muscle contraction and urethral sphincter muscles relax.
What are the two broad categories of urinary incontinence?
Neurogenic and non-neurogenic
What does USMI stand for?
Urethral sphincter mechanism incompetence
How does urethral sphincter mechanism incontinence normally present?
Intermittent voluntary leaking of urine when the dog is relaxed or excited. Can occur with ectopic ureters.
What is the most common signalment of ureter sphincter mechanism incontinence?
Female, spayed, older, large breed and overweight
How do you manage ureteral sphincter mechanism incontinence?
Sympathomimetic agents
Phenylpropanolamine, propalin and urolin
Oestrogens
How does detrusor instability present?
Overactive bladder presenting as pollakiuria. Underlying cystitis - urge incontinence
How do patients with urinary retention present?
Stranguria or dysuria and unsuccessful attempts to void urine
What are the two causes of urinary retention?
Detrusor muscle isn’t working well or bladder is contracting against high outflow pressure
What are some examples of lower motor neurone disorders involving the urinary tract?
Cauda-equina syndrome
Sacroiliac luxation
IVDD
Sacrococcygeal trauma
Neoplasia
What treatment/care should be undertake to manage lower motor neurone disorders?
Bethanechol (parasympathomimetic)
Manual bladder expression 3-4x a day
Cleaning
Monitor for UTI
How does the bladder typically present with upper motor neurone disorders?
Large, firm and difficult/impossible to empty
What is idiopathic reflex dyssynergia?
Loss of coordination between the detrusor muscle contracting and the relaxation of the urethra causing a spurting urine flow.
What does idiopathic reflex dyssynergia result in?
Bladder not emptying properly, overstretched bladder
What are struvite crystals composed of?
Magnesium ammonium phosphate (MAP)
What are struvite crystals normally associated with?
UTIs caused by urease producing bacteria
What are the risks for calcium oxalate crystals?
Acidifying diets, oral calcium supplements given outside of mealtimes, excessive dietary protein, formation of concentrated urine
What are urate crystals composed of?
Uric acid, sodium urate or ammonium urate
What breeds are pre-disposed to urate crystals?
Dalmatian and Black Russian terries
What are urate crystals commonly associated with?
Porto-systemic shunts
What signalment is related to cysteine crystals?
Intact male dogs
What are the risk factors for calcium phosphate crystal formation?
Excessive dietary calcium, primary hyperparathyroidism, UTI
What are the risk factors for xanthine crystals?
Genetic predisposition, acid urine, highly concentrated urine, urine retention, allopurinol treatment
Which urinary crystals are radiopaque?
Calcium oxalate, struvite, calcium phosphate
Which urinary crystals are radiolucent?
Xanthine
Which urinary crystals vary in opacity on radiographs?
Urate and cysteine
Which urinary crystals have a high rate of recurrence?
Calcium oxalate
What is the most common malignant renal tumour?
Renal carcinoma
What signalment is common with nephroblastoma?
Young male dogs less than <1year of age
What are the clinical signs of renal neoplasia?
Haematuria, dysuria, Stranguria and pollakiuria
Abdominal pain, palpable, enlarged kidney
Thickened bladder, cord-like urethra
What breed is predisposed to cystic transitional cell tumours?
Scottish terriers
