Urinary System I and II

what are the three things affecting RPF

blood volume

cardiac output

number of functioning glomeruli

local BP control - afferent and efferent arteriole haemodynamics

what substances does the kidney sometimes secrete

prostaglandins

kallikreins

endothelins

adrenomedullins

function of distal tubule

consrve sodium with chloride

remove potassium to conserve sodium

water

what is the word for urine that is too dilute

hyposenthuria

what is the definition of azotaemia

increase in urine or creatinine or both in the blood, so lower in the urine

how does renal ischaemia manifest, and how does it cuase azotaemia

poor renal perfusion

infarction

destrucitono f tubules due to no blood

post renal reasons for azotaemia

obstruction of the urinary tract

bladder rupture/uroperitoneum

when does urine volume start to increase

stages 2 and 3 ddue to less concentrating ability - hyposenthuric urine

what could oliguria and anuria indicates (2)

obstruction

ESKD

why might urea decrease before creatinine

caught renal insufficiency

pre-renal azotaemia

how is creatinine produced

endogenously by muscles at a constant rate

what are the two methods of measuring creatinine

enzymatic reaction - coloured complex

picric acid reaciotn - coloured complex

why is SDMA a better substance to use when looking for renal failure

it increases in the blood at 25-40% loss of function, so is more sensitive and catch earlier

what produces FGF-23 and why

osteocytes due to high phosphorus in teh blood

what three ocnditions increase phosphorus int eh blood other than renal failure

uncontrolled hypothyroidism

severe anaemia

severe inflammation

why don’t cattle have increased phosphorus levels with renal issues

more is excreted into the rumen and by saliva than with the kidneys

what causes hypercalcaemia

horse diet rich in calcium

how is amylase and lipase measured

DGGR lipase

what is anuria

no urine produced

what does yellow-green urine mean

biliverdin

what does supernatant red

haemoglobin in urine

how much should you fill the refractometer

full

what is 1.025

adequate concentrating ability in large naimals - more water in plants

what cuases hyposenthuric urine

with azotaemia - DI so central or nephrogenic

otherwise could be normal

what level is isothenuric urine

1.007-1.012-15

what are other cuases of nephrogenic DI

hypercalcaemia

polydipsia

diuretic therapy

uterine pyometra

hypoparathyroidism

psychogenic

liver failure and so on

what causes acidic cow urine

drinking milk

how does UPCr work

creatinine isn’t secreted or reabsorbed so is GFR - renal clearance of a subsstance and then compare with protein levels - don’t concentrate urine

how to measure Ig in the urine

Bence Jones protein test - light chian protein precipitation

protein electrophoresis - concentrate the urine

how many reasons for glucosuria

3

causes of bilirubinuria

pre-hepatic, hepatic or psot-hepatic disease

haemolytic anaemia

dogs can conjugate bilirubin a bit and excrete so 1+ in males

how many ml of sample to use for sediment analysis

5ml

calcium oxalate shape and colour

colourless

dipyramidal/octahedral/envelope

2 possible shapes of bilirubin

reddish-brown needles

flashlight/lollipop

which one is a thornapple

ammonium urate

which one indicates acidic urine

cystine

what stain to use with hyaline casts so they are visible

sedistain

how are epithelial casts attached

hyaline matrix by fibrin bands

what is a high WBC count

10 per x40 HPF

what if bacteria are present with inflammatory cells

bacterial infeciton - cystitis or pyleonephritis so consider clinical signs and culture and sensitivity with sterile sample if recurrent

two other tests

fractional excretion test

analysis or urinary enzymes test