Renal Disease Flashcards
(57 cards)
1
Q
Proctodeum
A
- last part of the cloaca where things are stored before being passed out of the body
2
Q
Urodeum
A
- where the urinary and reproductive tract empty into
3
Q
Coprodeum
A
- where the colon and GIT empties into
4
Q
Why is bird and reptile urine not a good representation of the function of kidneys like in mammals?
A
- urine can be modified by the bladder/colon
5
Q
Clinical signs of renal disease in birds
A
- early signs of dz are often subtle
- signs of advanced dz are often non-specific, e.g. fluffed-up, lethargic, anorexic, dehydration
- PUPD
- unilateral or bilateral himblimb paresis/paralysis (due to proximity of nerves)
- haematuria
- feather plucking over kidneys
- articular (& visceral gout) -> swollen painful joints
6
Q
Clinical signs of renal disease in reptiles
A
- early signs of dz often subtle
- signs of advanced dz are often non-specific e.g. lethargy, anorexia, weight loss, dysecdysis, abnormal thermoregulation/behaviour
- hindlimb weakness
- constipation (renomegaly in pelvic canal)
- gout (articular or visceral)
- oedema (nephrotic syndrome)
- PUPD are not usually a feature of reptile renal dz
7
Q
Dysecdysis
A
- problem shedding
8
Q
Clinical exam
A
- assess pt from afar
- inspect cage, droppings, food, etc
- thorough history
- birds may need to be placed in a warm, humidified oxygen cage first
- reptiles: ensure pt is warm
- hr, rr slows, less alert if cold so can misinterpret CE if cold
9
Q
Assume all ‘sick’ birds and reptiles are … dehydrated
A
- 5-10%
10
Q
Signs of dehydration in birds
A
- mouth: can’t do CRT in these spp but may look dry
- skin: skin tent elasticity is not a reliable indicator in birds
- eyes: dull and sunken (wrinkled skin around the eye)
- circulation: basilic wing vein refill time is a good indicator
- weight loss (esp if sudden)
11
Q
Signs of dehydration in reptiles
A
- skin: dry, wrinkled or puckered skin, loss of skin elasticity and flexibility, dysecdysis. skin tent is never an indicator of hydration status in reptiles
- eyes: sunken, receded eyes
- MSK: generalised weakness and lethargy
- mouth: tacky or dry mm, thick saliva
- coelomic: doughy on palpation, constipation or infrequent defaecation
- weight loss (esp if sudden)
- appearance of urates and urine
12
Q
Common causes of primary renal dz in birds
A
- inadequate diet
- hypovitaminosis A
- hypervitaminosis D3
- lipidosis
- heavy metal toxicity
- infection (primary or secondary from a systemic infection causing nephritis)
- neoplasia
- amyloidosis
13
Q
What is hypovitaminosis A thought to cause?
A
- metaplasia of the renal tubules and urethral epithelium
14
Q
What does hypervitaminosis D3 cause?
A
- hypercalcaemia
- soft tissue mineralisation (can be within the kidneys)
15
Q
Causes of lipidosis
A
- high fat, low protein diet
- period of starvation
16
Q
Relevance of lipidosis to the kidneys
A
- lipid deposits happen in the kidneys
17
Q
Which bird spp are renal tumours common in?
A
- budgies
18
Q
How do renal tumours often present?
A
- lameness in 1 leg due to the tumour pressing on the nerve plexus
19
Q
When does amyloidosis generally occur?
A
- after a period of chronic inflammation, e.g. pododermatitis
20
Q
Why does amyloidosis cause renal dz?
A
- amyloid deposits can damage the glomerulus
21
Q
Common causes of primary renal dz in reptiles
A
- inadequate husbandry (low humidity, temperature, diet [high protein], hypovitaminosis A, hypervitaminosis D3)
- chronic dehydration
- bacterial infection (primary or secondary from a systemic infection causing nephritis)
- neoplasia
22
Q
Why can too high temperature cause renal dz in reptiles?
A
- too high temp -> dehydration
- chronic dehydration -> underperfusion of the kidneys
23
Q
Why can low humidity cause renal dz in reptiles?
A
- linked to temperature but also causes dehydration if less droplets are in the environment
24
Q
What is gout a sign of in birds and reptiles?
A
- renal failure
25
Visceral gout
- accumulation of urate (uric acid) deposits in soft tissues, e.g. liver, pericardium & kidney
26
Articular gout
- accumulation of urate (uric acid) deposits in and around joints e.g. often feet and hocks
27
When does gout occur?
- when uric acid secretion is decreased
- +/- when uric acid production is increased
28
Cause of increased uric acid production
- excess dietary protein
29
Causes of decreased uric acid secretion
- pre-renal: dehydration (causing underperfusion of the kidneys)
- renal: renal tubular dz, hypovitaminosis A, infection/inflammation
- post-renal: obstruction e.g. uroliths, egg binding
30
Biochemistry (urea) use in birds and reptiles
- birds: may help assess dehydration but NOT kidney dysfunction
- reptiles: may be elevated in dehydration or anorexia. renal dz likely if uric acid also raised
31
Biochemistry (creatinine) use in birds and reptiles
- not very useful in birds or reptiles
32
Biochemistry (uric acid) use in birds and reptiles
- elevated only when >70% kidney function is lost
- mild to no elevation in dehydration
- post-prandial rise in carnivorous birds and reptiles: fast carnivorous birds for 24h before sample, fast carnivorous reptiles for 24-36h before sample (most presented anorexic)
33
Biochemistry (phosphorous) use in birds and reptiles
- birds: may be elevated in renal failure (& haemolysis)
- reptiles: may be elevated, renal failure more likely if phosphorous higher than total calcium
- hyperphosphataemia is often the 1st biochemistry abnormality
34
Biochemistry (potassium) use in birds and reptiles
- elevated in acute renal failure (& haemolysis)
35
Biochemistry (sodium) use in birds and reptiles
- birds: hypernatraemia in dehydration and hyponatraemia in renal failure
36
Urinalysis use
- difficult to obtain pure/sterile sample (hard to avoid faecal contamination)
- normal urine contains crystals and bacteria
- look for renal casts, abnormal cells, glucose (birds), Hexamita parasite (reptiles)
- urine can be modified after the kidneys in many exotic species therefore not a good indicator of renal function
37
Urinalysis use in birds
- USG range 1.005-1.020 but is species specific
- USG not very helpful in most cases
38
Urinalysis use in reptiles
- pH may change from normal alkaline to acidic in anorexic herbivores and post-hibernation
- USG range 1.003-1.014 may elevate slightly in dehydration
- USG not very helpful in most cases
39
Murexide test
- test used to confirm gout
- sample of material (e.g. joint aspirate) is mixed with nitric acid and dried over flame
- add 1 drop of concentrated ammonia
- if turns mauve = uric acid
- rarely done in practice
40
Radiography in birds
- 2 views: ventrodorsal and lateral (wings and legs extended)
- under GA
- normal kidneys difficult to see esp on VD view
- gonad and pelvic may obscure lateral view
- small rim of air dorsal to the kidneys on lateral view, this is absent in renomegaly
- look for changes in size, density & contour, eggs, cloacaliths, evidence of gout (white deposits within soft tissues / joints) and whole of body
41
Radiography in reptiles
- 2/3 views: ventrodorsal, horizontal-beam lateral +/- horizontal-beam craniocaudal (Chelonia)
- kidneys often difficult to see unless enlarged or increased density
- look for changes in size, density & contour, eggs, uroliths, gout and bone density (MBD)
42
MBD in reptiles radiographic findings
- decreased bone density (look at digits)
- pathological fractures
- constipation secondary to hypocalcaemia
- MBD could be RSHP (renal) or NSHP (nutritional)
43
Tx for birds (what all sick birds require)
- keep warm, quiet, away from predators
- fluid therapy
- commence oral fluids once birds is more stable
- crop feed once birds tolerates oral fluids (build up) (due to increased risk of aspiration in really sick birds)
44
Fluid therapy in birds
- SC, IV, IO depending on severity of dehydration, the birds demeanour and whether the GIT is functional
- use CE, PCV & TP to determine dehydration %
- 50mg/kg/day for maintenance + 50% of the fluid deficit daily
- high risk of fluid overload esp in smaller birds so calculate deficit
45
Antibiotics in birds
- aminoglycosides are nephrotoxic
- TMPS can potentially be nephrotoxic if a bird is severely dehydrated
46
Allopurinol in birds
- = xanthine oxidase inhibitor
- used to reduce uric acid in the blood and body
- care as some animals have a sensitivity to it (red tail hawks)
- don't use in chickens: licensing not allowed for FPA (even if pet)
47
Metoclopramide in birds
- 0.5-1mg/kg IM q8-12h if crop stasis
- don't use in chickens: licensing not allowed for FPA (even if pet)
48
Tx for reptiles (what all sick reptiles require)
- heat: pts should be kept at POTZ
- light: appropriate UVB light for the spp
- ensure correct humidity and appropriate access to water, eg. bath, spray
49
Bathing reptiles
- should be performed daly in all inpatients
- encourages drinking, voiding urine/faeces and some can suck fluid into the cloaca/bladder
- can add meds or supplements to the bath e.g. Reptoboost
- close monitoring is essential to prevent drowning even in aquatic spp
50
Oesophageal/stomach tubing in tortoises
- oesophagus on left side of the neck, stomach also on the left side
- keep upright to prevent immediate regurgitation
51
Antibiotics in reptiles
- most infections are caused by gram-negative bacteria
- aminoglycosides are nephrotoxic
- ceftazadime is commonly used
52
Allopurinol in reptiles
- = xanthine oxidase inhibitor
- may help reduce hyperuricaemia
53
Prevention of renal dz (husbandry)
- correct temp, humidity, lighting, etc
- fed the correct, balanced diet
- correct use of supplements in insectivore reptiles to correct the Ca:P imbalance
- keep hydrated by offering daily fresh water correctly
- bathe reptiles regularly
54
Hypovitaminosis A prevention
- give balanced diet with multivitamins such as Nutrobal by Vetark (calcium, A, C, E, D3, K3 and group B vitamins)
55
Hypovitaminosis A
- typically an issue in omnivore or carnivore species (carnivores have to get vitamin A from animal sources (e.g. liver))
- will generally have other nutritional deficiencies as well due to imbalanced die t- so diet always needs correcting
56
Can herbivores convert vitamin A from plant material/
yes
57
When to use vitamin A to tx hypovitaminosis A
- only use if severe, due to risk of over-dosing (toxicity)
