MT 2 Flashcards
What faeces tests are useful for EPI determination/diagnosis?
- Faecal elastase test (by ELISA method)
- Determine whether the faecal sample contains elastase or not. In case of EPI; no elastase - Examining undigested particles in faecal sample.
Three faecal smears should be prepared.
a) One smear is stained with Giemsa
b) Second with Lugol-solution
c) Third with Sudan III.-solution.
Results:
a) Giemsa: undigested striated muscle fibers (from meat)
b) Lugol: undigested starch particles as bluish patches
c) Sudan III: undigested lipid particles as red droplets.
If EPI is suspected to be complicated with severe bacterial enteritis, Gram-staining of one faecal smear can help us choosing the right antibiotic before bacterial culture of the faeces is ready (it takes some days, but severe enteritis should be treated immediately).
How can urine specific gravity be measured? When is the urine hypo-, normo- and hyperstenuric?
- Measured by:
1. Urinometer: Most accurate, easy and cheap. Urine poured into glass cylinder, urinometer placed inside. Requires a lot of urine.
2. Refractometer: Easy and one drop enough. Not reliable when urin is not transparent.
3. Test strip: not very useful for SG meas. in animals.
a) Hyposthenuria: <1,008. - Physiol. if incr. water intake.
- Hyperadrenocorticism
- Decreased ADH-prod. (CDI)
- Resistance to ADH (PDI or NDI)
- Renal tubular damage and PP.
- Also hypoadrenocorticism, liver disease and prolonged fluid therapy - due to medullary washout.
b) Isosthenuria: 1.008-1.012 - Physiol. if incr. water intake
- Severe tubular damage
- Medullary washout
- CDI, NDI or PP
c) Hypersthenuria: >1.012 (normal urine) - Decreased water intake
- Substantial water loss (vomiting, diarrhoea, excessive exercise: panting-dog, sweating-horse)
- Acute kidney failure (oliguria).
- May also be incr. in DM.
What is ALT? Causes of increased activity?
Alanine-aminotranferase -Liver cell (parenchymal) enzyme -Location: liver cells, RBCs in cytoplasm -Liver specific in Ca, not herbivores -Determination: piruvic acid (converted from L-alanine by ALT) is converted to lactic acid by LDH in the reagent -> discoloration of a chromophor. Causes of increased activity: -liver cell damage (esp Ca) -chronic active hepatitis -cholangiohepatitis -virus hepatitis (human) -hepatic lipidosis -cirrhosis -bile duct obstruction, -liver neoplasm, -pancreatitis, -septicaemia, -some drugs -copper storage disorder: Doberman pincher, West highland white and Bedlingtone terrier.
Proximal and distal ileus
Distal ileus: (jejunum and more distal parts):
-Metabolic acidosis due to dehydration, anaerobic GL and LA form.
-Animals do not eat, stomach is empty
-Vomit contains small intestinal fluid (because of reflux - miserere) w. high pH
Proximal ileus (stomach, prox. duodenal part):
-Metabolic alkalosis in beginning, then metabolic acidosis
-Irritant (foreign body) is in/near the stomach, and there is obvious gas and fluid accum. in stomach -> tensor receptors in gastric wall are activated causing incr. HCl prod.
-Vomit contains HCl -> metabolic alkalosis.
-As the process becomes more severe, dehydration and anaerobic GL develops (lactic acid form) -> metabolic acidosis
-Clinical signs (severe vomiting, dehydration, anorexia, depression, etc.) are more prominent, and the general state of the animal is worsening more quickly.
List and group the liver enzymes. What information is gained about the liver in case of enzyme deviations?
LIVER CELL (PARENCHYMAL) ENZYMES:
Incr. of cytoplasmic enzymes: mild liver cell damage
Incr. of mitoch. enzymes: more severe liver cell damage
- AST (Aspartate-aminotransferase) (mitochondria)
- ALT (Alanine-aminotranferase) (cytosol)
- GLDH (glutamate-dehydrogenase) (mitoch.)
BILE DUCT OBSTRUCTION ENZYMES:
- ALKP (AP-Alkaline-phosphatase) (every cell membr.)
- GGT (gamma glutamyl-transferase)
OTHER LIVER SPECIFIC ENZYMES:
(parenchymal enzymes)
Increase: liver cell damage
- OCT (ornityl-carbamyl-tranferase,
- Ar (arginase)
- SDH (sorbite dehydrogenase)
What is AST, where is it found? When is it increased? In what species is it useful?
-AST (Aspartate-aminotransferase)
-Liver cell (parenchymal) enzyme
-Location: mitoch. of liver cells, muscles (incl. heart), RBCs
-Liver specific in herb.
Causes of increased activity:
-Muscle cells: intensive exercise, training, muscle necrosis, myositis, muscle injury (im. inj.), myocarditis, muscle neoplasm.
-Liver cells: ethanol consumption (Hu), hepatopathy (Herb.), severe parenchymal damage (Ca)
-from RBCs: haemolysis
Species it is useful: all (not routinely in dogs+cats)
WHAT TO MEASURE of liver enzymes?
Dog: ALT, (AST, GLDH), ALKP, GGT Cat: ALT, (AST, GLDH), GGT, (ALKP in acute processes) Ruminants: AST, GLDH, (GGT) Horse: AST, GGT, (Arg) Swine: AST, GGT, ALKP, OCT, SDH
What is GGT? Causes of increased activity?
GGT (gamma glutamyl-transferase)
- Bile duct obstruction enzyme
- Location: prod. by different organs (kidney, pancreas, intestines and liver)
- Endothelial cells of bile duct conc. it.
- GGT of liver origin appears in blood.
- Liver specific in horses (and cats).
- Increased: biliary stasis, cholangiohepatitis, cirrhosis, neoplasm (hepatic, pancreatic), hepatic lipidosis, barbiturates, ethanol (human)
- Measured in all animals (not routinely in Ru)
Detecting protein from urine?
- Test strip: brome-phenol-blue (semi-quant. in-house test). Most sensitive to albumin, not Bence-Jones proteins. Physiological result: negative. Not specific,
- Sulphosalicylic acid test: (semi-quant. in-house test, by side of animal) coagulation: higher prot. cc. -> more opaque. Not specific.
- Heller/Gmelin test: HNO3 (rough inhouse test). Show bile-pigment metabolites and proteins the urine. Semi-quantitative scale.
- Spectrophotometric method: objective and quantitiative. Can measure TP content. Not specific.
- Urine protein : creatinine ratio (UPC): gives info about the severity of proteinuria if there is no sign of inflam. or macrohaematuria.
- Specific methods: Alb and/or glob can be evaluated using spectroscopy, (immune)electrophoresis, western-blot etc.
- Determination of Bence-Jones proteins: (heat labile) heat urine to 40-60o -> the proteins are coag., but 80-100o -> dissolved (unlike other proteins). Precise and quantitative detection using urine electrophoresis or HPLC
List the laboratory tests which allow us to evaluate the impairment of glomerulus-function.
1) Urea-colour test
NH3 in water forms NH4+. NH4+ forms green colour in alkalytic pH with Na-hypochloride and salycilic acid. Measured spectrophotometrically on 600 nm wave length.
(End point reaction, linear till 24.97 mmol/l urea cc.)
2) Enzymatic urea method: Change of NADH + H+ -> 2 NAD+ causing light emission change, measurable on 340 nm wave length. After 30 seconds of preincubation, the extinction change is measured within 1 min.
(Kinetic reaction, linear till 65 mmol/l urea cc.)
- Normal value: 8-10 mmol/l
Causes of increased blood urea concentration?
- ) Prerenal factors:
- Increased Nitrogen (protein) intake
- In ruminants: poor Energy status in the rumen.
- Increased Intestinal protein catabolism
- Intestinal or gastric bleeding
- Haemolysis
- Decreased blood perfusion of the kidneys - ) Renal factors:
- Kidney function, decreased amount of functionally active nephrons, decreased tubular function - ) Postrenal factors:
- Inhibition of urine flow through the lower urinary tract
- Rupture of the kidneys, urether, urinary bladder, or urethra: “uroperitoneum”
Causes of decreased blood urea concentration?
- Impaired liver function: decr. urea synthesis in liver cells from NH3, leading to incr. NH3 level.
- Haemodilution (hyperhydration)
- Decreased protein intake (starvation, anorexia)
Causes of increased blood creatinine concentration?
(normal value : 50-200 µmol/l)
- inflam. of muscles (myocarditis, rhabdomyolysis)
- rhabdomyosarcoma
- muscle trauma
- increased meat intake
Causes of decreased blood creatinine concentration?
(normal value : 50-200 µmol/l)
- cachexia
- chronic muscle atrophy
What is proteinuria? General causes? Non renal causes?
-Presence of abnormal quantities of protein in the urine.
-Caused by glomerulonephropathy, tubular transport defect, inflammation, infection or marked haematuria within the urogenital tract.
Pre-renal (non-renal) causes of proteinuria:
(1) physiologic or benign: in neonates below 40 hours of age, after strenuous exercise/heat or cold exposure/stress.
(2) pathologic: incr. protein catabolism: in fever, seizures, incr. BP, dysproteinaemias, haemoglobinuria, severe intravascular haemolysis and severe muscle injury.
What info is provided by the urine TP/creatinine ratio? Where can it be used?
-Provides valuable info about the severity of proteinuria if the evaluation of the sediment does not show evidence of inflammation or macrohaematuria. Calculation of UPC allows correction for variation in urine SG, due to the fact that creatinine excretion is relatively stable and after
excretion it is not reabsorbed in the tubules.
-Interpretation: normal: <0.5; grey zone, equivocal result: 0.5-1.0; proteinuria: >1.0; significant proteinuria: >2.0.
Proteinuria is indicative of glomerular disease (glomerulonephritis, PLN, amyloidosis).
Water deprivation test - What is the goal of this test, its method and interpretation.
- Goal: to assess concentrating ability of tubules, to differentiate bw CDI, NDI and PP.
- Principle: artificial induction of 5% dehydration in controlled environment and repeated meas. of urine SG.
- Indications: persistent PU/PD, more than one
urine SG meas. result in the range of hyposthenuria. - Procedure:
A) Partial water restriction for 2-3 days prior to test.
B) Bladder emptied by catheterisation, urine SG and BW recorded. Water and food withheld.
C) In 1-2 h. intervals BW monitored and bladder emptied (urine SG meas.) by catheterisation.
D) Procedure continued until BW reache 5% decr. or urine SG>1.025 or animal becomes depressed/azotaemic.
Interpretation:
a) in case of PP urine SG will become > 1.025.
b) In case of CDI or NDI urine SG will be ≤1.010
c) Values bw. 1.010-1.020 are equivocal and may suggest suboptimal cc. ability in tubules.
(differen. bw CDI and NDI: desmopressin response test) - Contraindications: severe endocrine disturbance, dehydration, azotaemia, uraemia, liver dysfunction, pregnancy, lactation, growth and inflam. disease.
What is the goal of Enzymuria Evaluation? How is it performed/tested?
Tubular cells contain enzymes (ALKP, GGT). Their release into the urine is incr. in case of acute/peracute tubular damage. The values must be referred to the creatinine levels in order to exclude the misdiagnosis caused by the high enzyme level in concentrated urine.
- Alkaline phosphatase (U/l) / Creatinine (µmol/l)
normal value: 0.02
- Gamma-glutamyl transferase (U/l) / Creatinine (µmol/l)
normal value: 0.01
Causes of abnormal urine pH (increased, decreased).
Increased:
1. Feeding in Ca: transient postprandial alkalization of urine.
2. UTI caused by urease-prod. bacteria like Proteus spp. and Staphylococcus spp.
3. Metabolic and respiratory alkalosis
4. Alkalizing substances, overload of bicarbonate- or lactate containing infusion
5. Long storage time: causes urea decomposition
to ammonia - eg. urinary tract obstruction
Decreased:
1. Metabolic and respiratory acidosis
2. Vomiting (paradoxical aciduria)
3. Hypokalaemia
4. Treatment with acidifying drugs (e.g. ammonium chloride).
5. Distalis renalis tubularis acidosis
6. Abomasal displacement
7. Toxicosis with acidifying substances (ethylene glycol, metaldehyde)
What is the goal of the electrolyte clearance, evaluation? How is it performed?
- Goal: Analysis of kidney tubular function (basic test)
- Generally in case of tubular damage, Na+ reabs. decr. (increased urinary sodium cc., and hyponatreamia), and usually K+ reabs. incr. (decr. urinary potassium cc., hyperkalaemia).
- Fractional electrolyte clearance %: (urinary Na+/plasma Na+) / (urinary creatinine/plasma creatinine) x 100
What can be seen in the physiological urine sediment? List the pathological abnormalities in the urine sediment.
ORGANIC sediments:
-RBCs and WBCs. Normal: <5 /hpf. Abnor: haematuria.
- Cells from lower urogenital tract: urothelium cells,
renal tubular cells, prostatic acinar, ductal epithelial cells, squamous cells from penis or vagina, sperm cells, tumour cells. Normal: 0-2/hpf. Abnor: inflam. or infection of upper/lower urinary tract, genital tract inflam., neoplasm.
-Viral inclusion bodies
-Microbes: bacteria, parasites, fungi
-Mucin, fat droplets (normal in cats), starch and pollen grains - contaminants.
-Casts: Abnormal: incr. number of casts
INORGANIC sediments:
-Large number of crystals and persistent crystalluria may lead to stone formation.
-Mostly in alkaline urine: struvite, calcium-carbonate, amorphous phosphate, ammonium-ureate/biurate
Mostly in acidic urine: calcium oxalate, uric acid, cystine, tyrosine, leucine, bilirubin crystals, sulphonamides
How can the presence of blood or haemoglobin be shown in the urine? How can the two be distinguished from each other?
-Benzidine test, urinary test-strip or microscopic evaluation
1. Benzidine test: Qualitative quick-test to show the presence of blood, haemoglobin or myoglobin. Use benzidine powder, H2O2 and acetic acid.
2. Urine test strip: (reagents of benzidine)
-Speckled appearance: haematuria
-Diffuse colour: haemoglobin- or myoglobinuria.
How to distinguish the two from each other:
1. Urine sediment analysis can diff. haematuria from haemoglobin- and myoglobinuria.
2. Centrifucation: Haematuria diff. from the other, since RBCs sediment, the supernatant clears up after centrifugation. In haemoglobinuria and myoglobinuria the urine supernatant remains reddish. While in haemoglobinuria usually concurrent reddish discolouration of plasma and anaemia are also observed, in myoglobinuria the plasma is clear and muscle damage indicator enzyme activities are elevated.
How can the presence of pus be shown in the urine? What are the causes?
-Pus is the accumulation of neutrophil granulocytes, some tissue cells, and microbes.
-Can be shown by Donne-test, microscopic evaluation of the sediment or using urine test-strip.
Causes:
-Physiological in horses
-Kidney pelvis inflammation
-Cystitis (inflam. in the urine bladder)
-Inflam. in genital tract, e.g. balanitis (inflam. of the glans penis) or prostatitis in males or vaginitis/endometritis in females.
What is TLI? Describe its usefulness in the diagnosis of EPI.
- Trypsine like immunoreactivity
- EPI if; TLI conc. is less than 2,5 µg/l
- Species specific parameter, which can be determined by RIA-method (radioimmunassay).
- Feature: antibodies are produced against one part of trypsinogen. ABs marked by radioisotopes are bound to trypsinogen of the sample. The marked AB-trypsinogen cause incr. radioactivity that can be measured by specific analyser.
- ELISA methods can also determine TLI.
