Clinical Chemistry 1.txt

Functional unit of the kidney - filtration and reapsorbtion

• 1. Filtration
• 2. Reapsorbtion
• 3. Storage

• Pt's blood pressure
• Amount of blood reaching glomerulus
• Laws of diffusion

• H20
• Electrolytes
• Glucose
• Amino acids
• BUN & Creatinine

Non-protein nitrogenous waste products

Protein breakdown --> ammonia -(liver)-> urea --> urine

Muscle contraction --> creatinine --> urine

• ADG
• Aldosterone

• Released from pituitary
• Tells renal tubules to reabsorb H20

• Released from adrenals
• Controls sodium reabsorption and pottasium excretion

100mg/dl

160-180mg/dl

If blood glucose is ABOVE renal threshold, filtered glucose will not get reapsorbed and glucose will be present in the urine

• Decreased H2O intake
• Most likely to show urine concentration
• Normal color is yellow
• Renal failure, can't concentrate urine
• Increased chance of observing abnormalities like crystals

Poor cytology because urine is "old", "old" cells

• Voided
• Manual
• Catheterization
• Cystocentesis

• Easiest on animal, clients can do, no iatrogentic trauma
• Not best method for culture because of bact. contamination.
• Mid-stream catch decreases contamination, collect into a clean container
• cats = empty litter pan with beads
• female dogs = pie pans
• horses = stimulate urination by rubbing warm wet cloth on lower abdomen
• cattle = stimulate urination by tickling vulva

• Can get bladder out of the way when pt is under anesthesia for abdominal surgery
• may require anesthesia, big dogs with tense muscles are hard
• May cause iatrogenic trauma and cause increased RBCs.
• Could rupture the bladder.
• Large animal = through rectum

• Can usually get sample right away
• Can clear obstruction
• Can monitor urinary output with a foley
• Ok for culture
• May require anesthesia, may produce trauma

• Can usually get sample right away
• Does not require anesthesia, animals usually handle better then catheterization
• Causes iatrogenic trauma --> RBCs
• 22g needle about 1"-1.5" long, 6cc or 12cc syringe, can do in dorsal but also lateral or standing
• Draw as much bladder as possible so hole shrinks, Do NOT redirect to avoid colon contamination

30 mins

6 hours

• Increased bact
• Increased crystals
• Urine gets cloudy
• Cells disintegrate
• Casts break down
• pH changes (tends to increase)

• 1 gtt 40% formaldehyde to 1 oz. urine
• If used, do chemistries first (dip stick)

• 1. Macroscopic eval
• 2. USG
• 3. Urine chemistries
• 4. Microscopic eval

Determines the function of kidneys and other organs

• Note color and concentration.
• Normal = straw - amber
• Dark yellow = increased concentration because of decreased H2O

• RBCS in urine. Red to reddish-brown and cloudy.
• Inflammation
• Trauma
• Urolithiasis
• Neoplasia
• Coagulopathy
• Rough cysto/catheter/manual

• HgB in urine
• Red/reddish-brown and transparent
• Usually with hemolytic plasma
• AIHA
• Incompatible blood transfusion
• toxins/poisons/snake venom
• RBC parasites

• Myoglobin in urine
• Red/reddish-brown
• clear plasma
• Muscle cell lysis:
• Exertional rhabdomyolysis
• Extreme muscle exertion
• Crushing injuries
• Heat stroke
• Electric shock
• Snake bites

• Bilirubin in urine
• Dark yellow/yellowish-orange/yellow brown
• Stains fingers
• Excessive hemolysis
• HBO
• Lover disease

Clear/transparent. Increased concentration = hazy

Cloudy due to crystals and mucus

• Clear if fresh
• Cloudy after standing

Cloudy, almost milky, due to crystals

Cystitis due to urease + bacteria

Pseudomonas or ketones (due to DM)

Protein

• Urine Specific Gravity
• Evaluates renal-tubule function
• (Response to ADH and reabsorption of H2O)

• Average 1.025
• 1.018-1.045

1.008-1.012 (1.015 in the cat)

Same USG as glomerular filtration

• range of 1.008-1.012 (1.015 in cats) that does change regardless of hydration status
• 1/3-3/4 nephrons are non functional
• Renal failure

• Pale/Dilute Urine
• Increased Fluid/Decreased "Stuff":
• Pyometra
• DI
• Cushings
• Diuresis
• IV fluids
• renal failure

• Increased concentration (dark yellow)
• Dehydration
• Acute renal failure/shut down
• Shock
• DM

Acidic

Alkaline

Dependent on diet

• high protein diets
• nursing young
• Protein catabolic states (high fever/starvation)

• Vegetable based diets
• UTI caused by Urease + organism
• Urine retention
• Urine allowed to stand open to air at room temperature

• 0-trace amounts of protein when sample is a cysto
• Slightly higher amounts from voided sample

Usually indicates urinary tract and kidney disease

NO

• Blood glucose exceeds the renal threshold
• 160-180 mg/dl dogs
• 280-300 mg/dl cats
• DM
• Stress/fear/excitement
• High carbohydrate meal

NO

• DM
• Prolonged anorexia/starvation
• ketosis in lactating and pregant cows and ewes (pregnancy toxemia)

1200-1500 rpm for 3-5 minutes

Used on urine sample to show nuclear detail on microscopic eval

• 1. Squamous Epithelial Cells
• 2. Transitional Epithelial Cells
• 3. Renal Tubular Epithelial Cells

• found in distal 1/3 of erethrea, vagina, vulva, and prepuse.
• Largest epithelial cell
• Nucleas is size of an RBC
• Normal in MILD amounts

• Line bladder, ureters, renal peelvis, and proximal part of the urethra
• Vary in size and shape
• Round, pear shaped, caudate
• Large nucleas
• Granular appearance
• normal in MILD amounts
• Seen more with cysto

• Urolithiasis
• Neoplasia
• Trauma

• Originate in the Renal Tubules
• Hard to ID

• Struvites
• Alkaline urine
• Normal in mild amounts
• Increased amounts can indicate Urolethiasis
• Coffin lids
• Coloreless
• Tx = acidify urine with diet

• Acidic urine
• Normal in MILD amounts in dogs, cats, and occ. horses
• Can indicate urolethiasis or ethylene glycol toxicity
• Tx = make urine alkaline with diet

• Form of Calcium Oxalate Monohydrate
• Always pathological
• Indicate Ethylene Glycol toxicity
• Look like picket-fence posts

• Common in horses
• Reason urine is cloudy when combined with mucus

• can be normal in dogs due to renal threshold for bilirubin
• Increased indicates liver disease

• Due to increased excretion of uric acide in urine, this is normal in dalmations and primates
• In all others can indicate portosystemic shunt and liver disease

• Never normal
• Most common in dachshunds

• Never normal
• Usually indicates severe liver disease

• Normal in dalmations
• Very little clinical significance
• Form as urine stands or if temperature fluctuates

• Can be normal
• Can indicate severe kidney disease
• RARE

• Recorded in #/LPF
• Form in lumen of distal renal tubules
• Tamm-Horsfall protein forms a gelatin mold
• Degenerate urine
• Need more acidic urine

• 1-2/LPF normal
• Colorless
• parallel sides and rounded ends, cylinder shaped
• Easily missed
• Increased with fever, strenuous exercise, mild renal irritation

• 1-2/LPF normal
• Increased numbers can indicate nephritis

NEVER normal

• RBCs incorporated into the Tamm-Horsfall protein.
• Deep yello to orange
• Indicates bleeding in kidneys or pathologic

• WBC in the tamm-horsfall protein
• Disorganized arrangement
• Indicates inflammation most likely due to pylonephritis

• Contain renal tubular epithelial cells
• hard to distinguish from WBC casts
• More organized arrangement of granules
• Indicates renal tubule damage

• Contain fat droplets
• DM or high fat diets
• More common in cats

• Rare
• broader, square ends
• more opaque then hyaline casts
• Indicates chronic severe degeneration of renal tubules

Stones.

• Something upon which a stone can form on
• Bacteria, crystals, suture, etc...

Oxalate

Struvite

• Most common in dogs and cats
• Alkaline urine
• Secondary to bacterial infection
• Converts urea to ammonia wich increases pH

• Uric Acid Stone
• Common in dalmations
• Restrict protein

• Hard stones with sharp protrusions
• Can damage the bladder
• Acidic urine

Increase in non-protein nitrogenous wastes in blood (BUN/Creatinine)

Measures level of urea in blood and therefor measures glomerular filtration

• dogs 7-27 mg/dl
• cats 16-36 mg/dl

• Azotemia
• increased protein diet
• increased breakdown of body protein

• liver disease
• Young animals
• Diuresis
• Starvation

Test measures level of creatinine in blood and measures flomerular filtration

• dogs 0.5-1.8 mg/dl
• cats 0.8-2.4 mg/dl

Azotemia

Diuresis

• Problem is BEFORE kidney
• Concentrated urine thus kidney is workin
• Increased BUN
• Increased Creatinine
• Increased USG

• Problem is with kidney
• Dilute urine
• 2/3-3/4 nephrons non functional due to age, nephrotoxins, lead and arsenic, drugs, and snake venome.
• Filtration and function do not work
• Increased BUN and Creatinine
• FIXED USG

• Probles is AFTER kidney
• Increased BUN, Creatinine, and USG
• Concentrated urine
• Urinary obstruction/rupture
• Emergency - can back up and cause primary azotemia