CA 1

What can influence reference intervals?

• Geographic location

• Season

• Species

• Breed

• Age

• Physiological factors (pregnancy)

• Technical factors (poor and incorrect sample submission, haemolysis, lipaemia, storage conditions, stability of analytes)

• Iatrogenic factors (drugs)

What are the stimulants for Haematopoiesis?

• Bone Marrow

• Haematopoietic Growth Factors (Poietins, Colony Stimulating Factors, Interleukins)

State the three main functions of Haematopoietic Stem Cells.

• Pluripotent

• Self-renewing

• Daughter HSCs (myeloid and lymphoid) cannot self-renew

What are the possible causes of anemia?

• Renal failure

What is the main stimulus for Erythropoiesis?

Tissue Hypoxia

What are the components that form an erythroblast/rubriblast?

GM-CSF, G-CSF, IL-3, Epo stimulate BFU-E to differentiate into CFU-E to form the Rubriblast

State the sequence of Erythrocyte maturation

Rubriblast → Prorubricyte → Rubricyte → Metarubricyte → Reticulocyte (Polychromatophil) → Erythrocyte

At what stages does cell division stop?

Rubricyte

Which blood cell is stained bluish-grey with Wright Giemsa?

Reticulocytes

At what stage is the nucleus extruded from the red blood cell?

Metarubricyte

How long does it take for the maturation sequence of Red Blood Cell?

4-7 days

What structures are stained with New Methylene Blue?

• Heinz Bodies

• Punctate Reticulocytes

What are indications of regenerative anemia?

• Macrocytes (Horses) with increased RDW and MCV (Horses)

• Appropriate Response: Nucleated Red Blood Cells (Rubricytes & Metarubricytes) in the peripheral blood

• Basophillic Stippling in cats and ruminants

• Howell Jolly Bodies

• Reticulocytosis (appearance 3-4 days)

• Low plasma protein (external bloodloss)

Which type of blood cell is not commonly in the standard reticulocyte count of cats?

Punctate Reticulocyte

What is the meaning of inappropriate rubricytosis and state the causes?

1. Increase in rubricytes without increase in reticulocytes.

2. Spleen removes nucleated rbc, an increase means splenic dysfunction, neoplasia or bone marrow disease.

What are seen in iron deficiency anemias?

• Hypochromasia with <MCHC (dogs)

• Microcytosis with <MCV

• Schistocytes

• Increase Total Iron Binding Capacity (TIBC)

An animal with spherocytes possibly possess?

• IMHA

• Coral Snake Bite

• Zinc Toxicity

Schistocytes are usually present when there is?

• Mechanical injury

• DIC

• Glomerulitis

• Vasculitis

• Portosystemic shunts

• Vascular Neoplasms (hemangiosarcoma)

• Iron deficiency anemia

A blood smear possessed, Echinocytes (Crenated cells), what does it suggest?

• Electrolyte Abnormalities

• Uremia

• In vitro changes

An animal’s blood smear showed several Acanthocytes, what does it suggest?

• Hemangiosarcoma

• Liver Disease

• DIC

• Iron deficiency anemia

What are the two types of Keratocytes and state their meaning.

1. Blister → Helmet

2. - DIC and Microangiopathic Hemolytic Anemia
   

A blood smear possess several codocytes (target cells), what might be a possible diagnosis?

• Liver disease

• Regenerative anemia

Dacrocytes (tear drop) are seen on blood smears. What might it suggest?

• Myelofibrosis

• Pure red cell aplasia

• Myeloproliferative disease

A malamute contains stomatocytes in their blood smear, what does it signify?

• Chronic anemia

• In vitro changes

Which type of iron forms an integral part of enzyme systems e.g. catalase, peroxidase, xanthine oxidase?

Tissue iron

What differentiates Haemosiderin from Ferritin?

• High iron:protein

• Not water-soluble

• Stained with Prussian Blue

Glucose entering RBC is catabolized via which pathway and state its end product.

Glycolytic pathway (Classic Anaerobic Embden-Myerhof) with lactate as the end product.

Pyruvate Kinase deficiency in the Glycolytic pathway is commonly seen in?

Basenji, Beagle, West Highland white terriers, Abyssinian and Somali cats

Phosphofructokinase deficiency in the Glycolytic pathway is commonly seen in?

English Springer Spaniels, American Cocker Spaniels

What is the purpose of the Pentose Phosphate Pathway (phosphogluconate pathway)?

Prevents oxidative injury to the red blood cell

Which pathway produces 2,3 DPG, which stabilizes Hb, thereby decreasing its affinity for O2 to promote O2 tissue delivery?

Diphophoglycerate pathway (Rapoport - Luebering pathway)

What are the two routes of old RBC removal?

1. Extravascular: Phagocytosis by MPS in the spleen

2. Intravascular lysis

State the sequence of Biliverdin to be excreted in urine.

Biliverdin -(Bilirubin reductase) → Bilirubin → Bilirubin Diglucuronide → Bile excretion in intestines → Urobilinogen OR Stercobilinogen

What is the end product of Biliverdin in birds?

Biliverdin due to lack of Biliverdin Reductase

What parameters are used to assess the mass of erythroid cells in the body (Erythron)?

• Hematocrit

• Hemoglobin (automated analyzer or spectrophotometer)

• RBC count

What two parameters are commonly used to classify anemias?

• MCV (cytic)

• MCHC (chromic)

State the cause of regenerative anemias and what type of anemia it is classified as.

1. Hemorrhage and Hemolysis

2. Macrocytic, Hypochromic

What are some changes in parameters from a patient suffering from acute blood loss?

• Hypovolemia

• Hypoproteinemia

• <PCV

• No change in Hct (only increased in horses due to splenic contraction)

• No change in reticulocytes or MCV

What are some changes in parameters from a patient suffering from chronic blood loss?

• Hypochromic, Microcytic

• Hypoproteinemia

What are some changes in parameters from a patient suffering from hemolytic anemia?

• <PCV

• Normal protein

• Regenerative

• Extravascular hemolysis: Icterus, bilirubinuria

• Intravascular hemolysis: Hemolysis, hemoglobinemia, hemoglobinuria

State the possible etiologies of Hemolytic Anemias.

• Immune-mediated (assess Ab using Coombs test)

• Toxin/chemical: Acetaminophen, Zn, Cu, Lepto, Clostridia, Snake/Spider venom, Onion, Garlic

• Infectious: Mycoplasma, Babesia, Cytauzoon, Equine Infectious Anemia, Leptospirosis, Bacillary Hemoglobinuria (Clostridia), Trypanosoma

• Mechanical Injury

• Inherited RBC defects: PK, PFK

• Hypophosphatemia

What are definitive signs of IMHA in dogs without the use of the Coombs test?

• Auto Agglutination

• Regenerative anemia

• Spherocytosis

• Anisocytosis

• Neutrophilia

• Left shift with monocytosis

What can cause non-regeneratve anemias?

• Chronic Inflammatory Disease

• Chronic Renal Disease

What parameters suggest non-regenerative anemias?

• Normocytic and Normochromic with normal neutrophils: FeLV, IMA, Liver disease, Hypothyroidism, Hypoadrenocorticism

• Normocytic and Normochromic with decreased neutrophils: Pancytopenia, FeLV, Parvo, Ehrlichia

• Microcytic and Hypochromic: Iron deficiency anemia, portosystemic shunts, liver insufficiency

• Macrocytic and Normochromic: B12 and B9 Deficiency, FeLV, Erythroid Neoplasia

What can cause Relative Erythrocytosis (no change in erythrocyte mass in the body)?

• Dehydration → <plasma volume → >RBC count

• Splenic Contraction

What can cause Absolute Erythrocytosis?

1. Primary: Neoplasia

2. Secondary:

   1. Appropriate: chronic hypoxia of cardiac/pulmonary disease

   2. Inappropriate

What is the half-life of neutrophils in circulation and state the period of time it takes for a mature neutrophil to enter circulation.

• 7 hours

• 4-9 days

What can cause decrease bone marrow efficiency?

• Age

State the sequence of granulopoiesis.

Stem cell → Myeloblast → Progranulocyte → Myelocyte → Metamyelocyte → Band Neutrophil → Segmented Neutrophil

What factors influence granulopoiesis?

IL-1,3,6, GM-CSF, G-CSF

What are the four indicators of toxic change of neutrophils?

• Dohle bodies

• Cytoplasmic basophilia

• Vacoulated or foamy cytoplasm

• Toxic granulation

What diseases cause intracellular inclusions?

Histoplasmosis, Ehrlichia, Hepatozoon, Distemper

What is the difference between a Regenerative and Degenerative left shift?

• Regenerative: Neutrophilia with segmented neutrophils

• Degenerative: Immature granulocytes =/> than segmented neutrophils

What can cause a Neutrophilia?

• Epinephrine: leuko/lymphocytosis, MNP → CNP

• Corticosteroids: Stress leukon (leukocytosis, neutrophilia, monocytosis, lymphopenia, eosinopenia)

• Inflammation/Infection: Leukaemoid reaction (pyometra, hepatozoon, canine leukocyte adhesion deficiency)

What can cause a neutropenia?

• Defective production

• CNP → MNP

• Emigration of blood

• Immune mediated destruction

What can cause a lymphocytosis?

• Epinephrine (cat): MLP → CLP

• Ag-induced lymphocyte proliferation: Ehrlichia, Babesia, FeLV

• Hypoadrenocorticism

• Lymphoid Neoplasia: FeLV, BLV

What can cause a lymphopenia?

• Corticosteroid

• CDV, Parvo, EIA

What is the largest cell in the blood?

Monocytes

What can cause a monocytosis?

• Infection/Inflammation with Neutrophilia

• Hyperadrenocorticism

• Myelomonocytic leukemias

What cells are recognized as bright red-orange granules in Romanowsky - stained blood and bone-marrow smears?

Eosinophils

1. What growth factor mediates eosinophil generation?

2. Where does mature eosinophils reside?

1. IL-5

2. Skin, GIT, Respiratory Tract

What can cause an eosinophilia?

• Parasitism

• Inflammatory/Hypersensitivity reactions: IgE

• Hypereosinophilic syndromes: Rottweilers

• Mast cell tumors

• Hypoadrenocorticism

What can cause an eosinopenia?

• Acute infection

• Corticosteroids

What cells possess a round-oval lobulated nucleus?

Basophils

A leukocytosis is characterized by?

• Neutrophilia without left shift

• Normal Eosinophils, basophils, monocytes, lymphocytes

Pseudothrombocytopenia is commonly seen in?

Cats

What can cause thrombocytopenia?

• Estrogens, phenylbutazone toxicity, myelosuppressive drugs

• Neonatal viral diseases: Parvo, FeLV

• Myeloproliferative disease

• Blood loss; rodenticide toxicity

• DIC, vasculitis, endocarditis

• Anaplasma platys (cyclic thrombocytopenia in dogs)

What can cause thrombocytosis?

• Epinephrine induced splenic contraction

• Iron deficiency, Vinca alkaloids

• Increase serum K

• Neoplasia

What are some characteristics of Extravascular fluids?

• Contains Interstitial fluids

• Composed of Na, Cl, HCO3

• Contains plasma

What are some characteristics of Intravascular fluids?

• Contains Transcellular fluids

• Composed of K, Mg, P, Proteins

1. What contributes to oncotic pressure?

2. What is the main determinant of plasma volume/osmolality?

1. Albumin

2. Na

What is the purpose of ADH (vasopressin)?

• Regulate blood volume and plasma osmolality (with Na)

• Arterial vasoconstrictor

What lab results are expected for dehydration?

• increased PCV(HCT)

• increased plasma protein

• azotemia (increased urea and creatinine)

• increased urine specific gravity

When an animal experiences hyperosmolality, what does it signify?

• Hypernatremia, Hyperglycemia, Azotemia, Ketonemia, Diabetes Insipidus

• Water shifting from ICF → ECF

When an animal experiences hypoosmolality, what does it signify?

• Hyponatremia, Hypoadrenocorticism

• ECF → ICF

What can cause Hypernatremia?

• Iatrogenic Anticoagulants: Na Citrate

• Salt poisoning

• CHF

• Hyperaldosteronism

• Inadequate water intake

• Water loss

  • Pure H2O: DM, Dyspnoea, Skin burns, fever, heat stroke

  • Hypotonic: diarrhea, vomiting, renal disease, pancreatitis

What can cause Hyponatremia?

• Hypoadrenocorticism

• Renal disease

• Prolonged diuresis, e.g., glucosuria, administration of diuretics, e.g., thiazides, furosemide, spironolactone

• Non-absorbable anions in tubules; ketones

• Vomiting, diarrhea, excess salivation, fluid loss from hypernatremia, third space loss (pleuritis, peritonitis, chylous effusions)

• Uroabdomen

• Sweating in horses

• Lactation

• Hyperglycemia

• IV fluids; Hypotonic

What does the term NOKIA stand for? (Abbreviation)

Na Outside

K Inside

What can cause Hyperkalemia?

• Inorganic metabolic acidosis

• Diabetes Mellitus

• Muscle damage or tissue necrosis

• Intravascular hemolysis

• Hypoadrenocorticism

• Decrease GFR = Decrease renal excretion

• Urinary Tract Obstruction

• K EDTA

What can cause hypokalemia?

• Metabolic alkalosis

• Insulin Therapy

• GIT losses: Salivation, vomiting, diarrhea

• Glucosuria

• Ketonuria

• Sweating in horses

What can cause Hyperchloremia?

• Secretory metabolic acidosis; loss of HCO3 due to renal tubular acidosis

• K bromide therapy

• Dehydration

• Salt poisoning

• Chloride therapy (KCl, NH4Cl), hypertonic saline

What can cause Hypochloremia?

• Vomiting, Abomasal fluid displacement, Upper GI Obstruction → metabolic alkalosis

• Hypovolemia + Hypochloremia + Hypokalemia → Paradoxical aciduria

• Concurrent loss of Na

• Furosemide/ Thiazide diuretic therapy

• Na HCO3

• Overhydration

Volatile acids (respiratory) involves?

Metabolism of carbs, proteins, fats for energy resulting in CO2 formation

Fixed acids (metabolic) involves?

Not excreted by the lungs and referred to by their anion (lactate, phosphate, sulphate, acetoacetate or b-hydroxybutyrate)

A patient experiencing hypoventilation will display?

Retention of CO2 → left shift of H+ (increase) + acidosis

Viceversa with hyperventilation; right shift of H+ (decrease) + alkalosis

What are the requirements for blood gas analysis?

• Heparin blood tube

• Na-heparin anticoagulant

• i-STAT anticoagulant analyzers are forbidden

• NH4 and EDTA affect pH

• Sample should be 37°C

• Immersed in ice bath and read in 1hr

• Air destroys the sample

• Venous blood: pH (H+ ion concentration), pCO2 and HCO3

• Arterial blood: pO2

• Acid base balance: pH, pCO2 and HCO3-

• High cost and rapid analysis

State the meaning of acidosis, alkalosis, acidemia, alkalaemia, base excess, anion gap

1. Acidosis: strong acid is gained or base is lost

2. Alkalosis: strong base is gained or acid is lost

3. Acidemia: decrease in blood pH

4. Alkalaemia: increase in blood pH

5. Base excess: assess metabolic changes

6. Anion gap: classify metabolic acidosis (titrational/secretory)

What can cause metabolic acidosis (<pH + <HCO3-)?

• secretional or hyperchloremic metabolic acidosis; diarrhea, salivation, renal loss

• titrational metabolic acidosis; diabetes, starvation, dehydration, shock, uraemic acids, grain overload, distal tubular necrosis

What can cause metabolic alkalosis (>pH + >HCO3-)?

• vomiting, low Cl intake, excessive HCO3- intake

What can cause respiratory acidosis (<pH + >CO2)?

• Hypercapnia (increase CO2 in blood)

• Anesthesia

• Intrathoracic/Intrapulmonary disease

• CNS disorder with depression

• Cardiopulmonary arrest

What can cause respiratory alkalosis (>pH + <CO2)?

• Tachypnoea (hyperventilation), Hypocapnia

• Extrathoracic: fear, pain, heat stroke

• Intrathoracic: ventilation

What are unmeasured cations and provide examples.

1. Charge of other cations in blood except Na and K

2. Mg, Ca, لا- globulins

What are unmeasured anions and provide examples.

1. Charge of other anions in blood except HCO3 and Cl

2. organic anions (lactate, pyruvate, ketones), inorganic anions (phosphate, sulfate), proteins (albumin, α and β globulins), exogenous anions (salicylates, methanol, ethylene glycol, paraldehyde)