MT 1 Flashcards
What different kinds of polycythaemia do we have?
- Normovolaemic polycythaemia: can be false, physiological (species, breed, age characteristics) or pathological. These are absolute polycythaemias e.g.
non-EPO or EPO dependent, true or false - Hypovolaemic polycythaemia: most frequent form of polycythaemia: relative polycythaemias: e.g. vomiting, diarrhoea, polyuria, loss of plasma e.g. burns)
- Hypervolaemic polycythaemia: acute stress, where vasoconstriction occurs together with spleen contraction (strenuous exercise, hyperthermia, fever etc.)
How do we examine the acute phase proteins and why is it important?
- Glutaric aldehyde test: fibrinogen (APP) and globulin
- ESR: APP attach to surface of RBCs - sediment quicker
- CRP: C-reactive protein (APP)
- Important because: The very first laboratory sign of inflammation is the increase of APPs in the blood and the decrease of negative APPs.
Causes of metabolic and respiratory alkalosis?
METABOLIC alkalosis causes:
- Incr alkaline intake: overdose of bicarbonates, feeding rotten food
- Incr ruminal alkaline prod: high protein intake, low carb intake, anorexia, hypomotility
- Decr hepatic ammonia catabolism (liver failure)
- Incr acid loss: vomiting, gastric dilatation volvulus syndrome, abomasal displacement
- Ion exchange: hypokalaemia: due to Henle loop diuretics
RESPIRATORY alkalosis causes:
-Increased loss of CO2: hyperventilation
*excitation
* forced ventilation (anaesthesia)
* epileptiform seizures
* fever, hyperthermia
* interstitial lung disease
Pathological RBC types
- RETICULOCYTE: appearance; incr prod, chronic Fe def anaemia, haemolysis, acute/chronic blood loss
- SPHEROCYTE: appearance; sensitive RBC membrane, IHA
- STOMATOCYTE: appearance; incr RBC prod
- ACANTOCYTE: (w. spikes) appearance: RBC membr failure – lipid metabolism disorder, hepatopathies
- SCHYSOCYTE: (RBC fragment) appearance: traumatic or toxic damage
- ANULOCYTE: appearance: iron def anaemia
- CODOCYTE: (Target cell) appearance: regenerative process
- ECHYNOCYTE: (Burr cell, spikes) appearance: lab error
- SICKLE CELL: appearance: RBC damage, Hb globin chain malformation in humans
- INCLUSION BODIES in RBCs:
- HEINZ BODY: (denaturated Hgb) appearance: O2 effect, oxidative damage to RBCs
- HOWELL-JOLLY BODY : (nuclear membr remnants), appearance: vit.B12 def, incr prod of red cells, splenectomy
- BASOPHILIC PUNCTUATES: (nuclear remnants) appearance: regenerative process, young RBCs of cat, physio. in Ru, lead poisoning
- HB INCLUSIONS: appearance: Hb damage, incr RBC prod, regenerative anaemia
Protein determination methods
- Total protein conc in blood (TP)
- Biuret test (usually photometrically)
- Ultrasensitive total protein analysis
- Refractometry
- Electrophoresis: examines globulins
- TT - Thrombin time: fibrinogen conc.
Laboratory evaluations for acute stress
-Physiological leukocytosis: on the effect of adrenalin, noradrenalin (epinephrine, norepinephrine), neutrophilia and/or lympocytosis, without left shift
Laboratory evaluations for chronic inflammation
- Right shift: many segmented and hypersegmented, old neutrophils are seen in the smear. Incr. WBC count.
- Haematology of Addison’s disease
- Pelger-Huet anomaly: Normocytaemia, and left shift
- Cyclic neutropenia: inhertitable disease of Grey Collies. Due to cyclic BM activity, neutropenia occurs in weekly, monthly intervals.
- Bone marrow damage: Leukopenia, and neutropenia occurs. Thrombocytopenia and aplastic anemia is often accompanied.
Addison’s disease
(hypoadrenocorticism)
- There is no inhibitory effect of glucocorticoids, as there is hypoplasia or necrosis of adrenal gland.
- The typical changes are increase in WBC (due to the polyuria caused increased PCV), increase in young neutrophils, left shift (no inhibition of cell proliferation), lymphocytosis and eosinophilia.
Lipid fractions and their transport
Lipid fractions : apolipoproteins :
- triacil-glycerols - VLDL
- phospholipids - HDL
- cholesterol - LDL/HDL
- cholesterol-ester - (HDL)
- free fatty acid - albumin
Lipid changes during starvation
-Decreased lipid content
-Increased FFA content
Total lipid (TL) conc decr because liver can not produce enough apolipoproteins for transporting lipids, however FFA conc is incr, because it is transported by albumin.
What are the methods for clotting time?
-Appearance of the first fibrin strand
-CT on watch glass
-CT in plastic syringe
-CT in glass tube
.CT in ACT (activated clotting time) tube
Thrombocytopenia
- Definition
- Tests
- Causes
- Decreased amount of thrombocytes in the blood
- Test: BT, BMBT
- Major causes:
1. decr prod in bone marrow
2. incr utilisation: DIC
3. incr destruction: autoimmune thrombocytopenia (AITP)
4. incr sequestration: in case of (chronic) splenomegaly
5. incr loss: subacute/chronic bleeding
Gammopathies
- Defintion
- Their graf
- Their causes
POLYCLONAL gammopathy: beta and gamma globulins derived from different clones
-Broad-based peak in beta and/or gamma region
-Causes:
*various chronic inflam. dis. (infectious, immune-mediated)
*liver disease
*FIP
*occult heartworm disease
*Ehrlichiosis.
*Beta-gamma bridging occurs in disorders with incr IgA and IgM such as lymphoma, heartworm disease and chronic active hepatitis.
MONOCLONAL gammopathy: one protein fraction derived from one clone
*Sharp spike in beta or gamma region
-Causes:
*during immune mediated or neoplastic conditions
*both neoplastic and non-neoplastic disorders
Ketone bodies
- Appearance
- Causes
- Test
- Appearance is due to energy deficiency in liver cells.
- Causes:
- Decr intake of carbohydrates
- Decr insulin prod. (diabetes ketoacidosis; incr. hepatic prod. of KBs)
- Ross reaction: estimate conc. of acetone, and acetoacetic acid: colour from white(grey) to purple. The depth of colour depends on ketone conc.
Hyperglycaemia – list the causes
(incr glucose conc)
-Transient increase:
o laboratory errors (haemolysis, lipaemia, icterus)
o stress (cats)
o food intake (dogs and humans)
o xylazin effect
o cranial trauma or inflam. (Rabies, Aujeszky disease)
o after/during adm. of glu-containing fluid therapy
-Constant hyperglycaemia:
o diabetes mellitus
o hyperadrenocorticism and glucocorticosteroid therapy
o progesterone effect (iatrogen or endogenous-insulin resistance)
o enterotoxaemia (sheep)
Hypoglycaemia - list the causes
(Decreased glucose concentration)
- lab error (incorrect storage/transport of sample)
- decr energy status (ketosis of Ru, growing pigs, etc.)
- insulin overdose
- insulinoma
- anabolic steroid effect
- liver failure, terminal stage
- acute liver failure
- hypoadrenocorticism
- septicaemia
- hyperthyroidism
- paraneoplastic syndrome
Reticulocytes
- Defintion
- Appearance
- How to count them
-Young, immature RBC w/ø nucleus
-Same functional properties as mature RBCs, so they are able to carry oxygen.
-Appearance: incr. prod. (regenerative anaemia) - chronic Fe def anaemia, haemolysis, acute or chronic blood loss
- No reticulocytes appear in horses and Ru (only in BM, not in the peripheral blood)
-Appearance is a sign of regenerative function of BM
-How to count reticulocytes:
*CRC-Corrected reticulocyte count:
CRC = reticulocyte % x RBC count
normal: <0,06 x 1012/l (w/ø anaemia)
-CRP-Corrected reticulocyte percentage:
CRP = (Htpatient / Htaverage (0,45 dog, 0,37 cat)) x reticulocyte %
normal: <1-2 % (w/ø anaemia)
List reasons for increased PCV
• False: long sample storage w. EDTA
• Physiological:
o Congenital
o Age: new borne animals
o Phys. long-term hypoxia: living in high altitude, regular intensive long training/work…
• Relative polycytaemia: decr plasma volume, e.g. lack of drinking water, vomiting, diarrhoea
• Absolute polycythaemia (normovolaemic): incr RBC prod
o Primary: without incr EPO
o Secondary: incr EPO
a) true: caused by long term hypoxia, due to chronic resp./circ. disorders
b) not true: without hypoxia: autonomous incr of EPO
• Complex problem: hypervolaemic polycythaemia – life threatening acute stress or extreme physical exercise
List reasons for decreased PCV
• False: microcytosis, inappropriate sample homogenization etc.
• Physiological: incr. plasma volume in the 3rd trimester of pregnancy
• Relative: pathological incr in plasma volume i.e. overdose of fluid therapy, terminal phase of chronic kidney insufficiency
• Absolute: normovolaemic oligocythaemias
o several hours after acute bleeding
o decr life-span in circulation e.g. IHA, ectoparasitosis
o sequestration of RBCs in spleen due to hypersplenismus
o decr RBC prod:
a) suppression of BM e.g. heavy metal poisoning, mycotoxins, drug side effect, viral infections
b) lack of nutrients e.g. iron, copper, B6, B12 vit, folic acid
• Complex problem: the abs. oligocyt. listed above frequently cause refusal of water, vomiting or diarrhoea leading to hypovolaemic oligocythaemia
Acid base evaluation
- Routine test in emergency patients.
- Gives info about acid-base status, and function of vital buffer systems.
- Acid-base analyzers are complex devices; measure also blood-gas parameters, electrolytes and eventually Hgb, Ht, lactate, glucose etc.
- Ionselective electrodes (ISE): measure pH and CO2
List methods for primary haemostasis tests
- Tests performed by side of the animals:
- Signs of incr bleeding tendency
- Capillary resistance (humans)
- Bleeding time BT, buccal mucosal bleeding time test, BMBT
- Appearance of the first fibrin strand (clotting time)
- Appearance of the clot
- Clot retraction time
Erythrocyte sedimentation rate (ESR) -Theory -Causes of increase -Samples -Phys.ESR value -
- Theory: there is incr sedimentation of RBCs due to inflam processes, as the APPs and other globulins tend to attach onto the surface of RBCs.
- Cause of incr. ESR:
- Incr globulin conc, due to inflam or neoplastic processes.
- Decr albumin conc and as a consequence relatively incr globulin conc causes incr ESR, too.
- Samples: Westergreen tubes (glass) - contains Na-citrate, and there is mm scale on it, and holes on the bottom and top
- Sedimentation rate of RBCs should be checked after 1h, horses every 20m (very fast in horses)
- Physiologically ESR: 0,5-3 cm/hour
pH of rumen
- Normal pH: bw 6.3–7 (slightly acidic)
- cows fed grain can have slightly lower, those fed hay or green slightly higher pH
- Abnormal pH:
- Elevated pH (Rumen alkalosis): Simple indigestion or reduced feed intake for greater than 2 days, urea indigestion, putrefaction of ruminal content from prolonged rumen stasis, saliva contamination
- Lowered pH 5.5.-6 (Rumen acidosis): Grain overfeeding, chronic ruminal acidosis
Left shift
- More young WBCs appaear in the circulating blood.
- Young metamyelocytes and band forms are visible in greater proportion and abs. nu. in blood smear.
- Two different types of left shift:
1. Regenerative left shift: Incr WBC count, neutrophilia, and left shift (younger neutrophils). Mature neutrophils outnumber the immature neutrophils. Sign of favourable prognosis, because BM have time to respond to the inflam. stimulus.
2. Degenerative left shift: Low, or normal WBC, neutrophil count and left shift (younger forms). Abs. nu. of band- or immature neutrophils are greater than the abs. nu. of mature/segmented neutrophils. Sign of poor prognosis; the disease is very serious and needs immediate treatment.
Thrombocytopathies
- Definition
- Causes
-Decreased ability of platelets to aggregate and adhere to the site of injury, and formation of the primary thrombocyte-thrombus, the second step of haemostasis
Major causes:
-improper development of platelets, for example because of hereditary glucoprotein deficiencies, etc.
-von Willebrand’s disease
-uraemia
-liver failure
-myelo-, and/or lymphoproliferative diseases
-NSAIDs
-etc.
Types of anaemia
=Oligocythaemia (decr RBCs or heamoglobin)
- REGENERATIVE a.: Incr. reticulocytes, macrocytic, hypohromic: MCV incr, MCHC decr, appearance of young RBCs, stomatocytes and Hb inclusions
- Hemorrhage, hemolysis
- Usually diseases with favourable prognosis, because enough new RBCs are prod in the BM to regenerate the anaemia and to reach normal RBC count quickly. - NON REGENERATIVE a.: normocytic, normochromic; MCV same , MCHC same, normal or decreased MCH
- Chronic anaemia diseases, chronic kidney dis., primary BM dis. - IRON DEF. a.: high TIBC, decr MCHC, appearance of anulocytes,
Normal range of electrocytes
- Sodium (Na+): 140-150(-160) mmol/l
- Potassium (K+): 3.5-5.5 mmol/l
- Chloride (Cl-): 100-125 mmol/l
- Calcium: 2.1- 3.0 mmol/l (Ca2+ is 45-50% of this), in poultry laying eggs tCa may be even double (~5.8 mmol/l)
- Magnesium: 0.8-1.5 mmol/l
- Inorganic phosphate (Pi): dog, horse: 0,8-1,8 mmol/l, cat, cattle, sheep: 1-2,4 mmol/l, swine, goat: 1-3 mmol/l.
Routinely used acid-base parameters
-pH: Actual pH of the blood: 7.35-7.45
-pCO2 - partial CO2 pressure (mmHg, kPa)
*respiratory parameter
* 40 mmHg
-HCO3 - standard bicarbonate (HCO3-) conc (mmol/l)
*In plasma, if the blood is equilibrated to 40 mmHg pCO2 on 37 °C - it`s value depends on pCO2
*metabolic parameter
* 21-24 mmol/l
-ABE - actual base excess/demand/residue (mmol/l)
*Titratable acidity or basicity; the amount of acid or base
needed to equilibrate blood to pH: 7.4
*metabolic parameter
* ±3.5 mmol/l
-TCO2 - total CO2 conc in plasma (mmol/l)
*i.e. CO2 content of blood liberated by strong acid.
*TCO2 is 5% higher than plasma HCO3-.
*gives no direct info about resp function.
*may be ignored, when HCO3- result is presented
* 23-30 mmol/l
-SBE standard or in vivo base excess/demand, residue in
the whole extracellular space
*metabolic parameter
* ±3 mmol/l
Hypokalaemia: causes and effects
Causes:
-decreased intake (anorexia)
-long term polyuria (e.g. chronic kidney insufficiency)
-adm of loop-diuretic drugs (e.g. furosemide)
-enteral potassium loss (e.g. diarrhoea, enteral bleeding)
-primary or secondary hyperaldosteronism, alkalosis and insulin
Effects:
-decreased neuromuscular irritability
-muscular weakness
-paresis
-glucose intolerance
-decreased insulin secretion
-decreased conductance of electrical stimuli in heart (bradycardia, arrhythmia)
-polyuria
-polydypsia
-Na+-retention
-alkalosis
Spectrophotometric Method (Drabkin-method)
- Usage
- Sample
- Reagent and it´s method
- Colour
- Wave length
- Calculation
- Normal value
- Haemoglobin (Hgb) Measurement
- Whole blood sample
- Reagent: K3Fe(SCN)6: hemolyses RBCs and forms
Fe3+, from Fe2+ in the haemoglobin molecule - Orange coloured end product
- 540 nm wave length.
- (Esample/Estandard) x standard conc = result (E=extinction)
- Normal: 18-20 mmol/l or 12-18 g/dl (g%)