Haematology 410 - Clinical Pathology
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the main function of the erythron?

  • Formation of blood clots
  • Defense against pathogens
  • Transport of oxygen to tissues (correct)
  • Regulation of body temperature

    • Which component is NOT a part of the haematopoietic system?

  • Liver
  • Lymphoid organs
  • Bone marrow
  • Lungs (correct)

    • Haemostasis involves the interaction between which of the following components?

  • Erythrocytes, leukocytes, and plasma
  • Blood vessels, platelets, and clotting factors (correct)
  • Blood vessels, platelets, and respiratory gases
  • Platelets, clotting factors, and leukocytes

    • What is the significance of the Complete Blood Count (CBC)?

    <p>It is the most frequently requested laboratory test reflecting physiological processes.</p> Signup and view all the answers

    Which cellular structure is crucial for maintaining red blood cell shape and integrity?

    <p>Cytoskeleton proteins</p> Signup and view all the answers

    What alteration in red blood cells can arise from changes in the lipid composition of their membrane?

    <p>Formation of abnormal cell shapes</p> Signup and view all the answers

    Which statement about leukocytes is correct?

    <p>They serve as the body’s defense mechanism.</p> Signup and view all the answers

    What is the primary role of the haematopoietic system in the body?

    <p>Serving as a host defense system and maintaining homeostasis</p> Signup and view all the answers

    What happens to the ratio of platelets to red cells when a patient is markedly anaemic?

    <p>One platelet per ten red cells</p> Signup and view all the answers

    What is the platelet count classification for normal levels?

    <p>≥ 200 ×10^9/L</p> Signup and view all the answers

    What is required for a newborn to have adequate IgG levels post-birth?

    <p>Normal birth and good health</p> Signup and view all the answers

    What distinguishes absolute polycythaemia from relative polycythaemia?

    <p>Total red cell mass is increased in absolute polycythaemia</p> Signup and view all the answers

    How is platelet count determined when counting platelets per white blood cell?

    <p>Multiply the count of platelets per WBC by the WBC</p> Signup and view all the answers

    What is the appropriate treatment for foals or calves diagnosed with Failure of Passive Transfer (FPT)?

    <p>Fresh frozen plasma transfusion</p> Signup and view all the answers

    What does polycythaemia refer to in a blood sample?

    <p>Increased concentration of erythrocytes</p> Signup and view all the answers

    What is the maximum volume of plasma that can be administered to foals with complete FPT?

    <p>40 mL/kg</p> Signup and view all the answers

    What is the primary treatment approach for inappropriate secondary absolute polycythaemia?

    <p>Treat the underlying cause and follow polycythaemia vera protocols</p> Signup and view all the answers

    Which of the following is NOT a type of lymphoproliferative disorder?

    <p>Acute myeloid leukaemia</p> Signup and view all the answers

    What defines lymphosarcoma or lymphoma?

    <p>Neoplasm confined to solid tissues</p> Signup and view all the answers

    Which statement about leukaemia is true?

    <p>It involves the blood and may originate from lymphoid or myeloid cells.</p> Signup and view all the answers

    What characterizes proliferative disorders?

    <p>Involve an increase in hematopoietic cell neoplasms in blood or bone marrow</p> Signup and view all the answers

    Which of the following conditions is associated with the production of a monoclonal immunoglobulin?

    <p>Plasma cell myeloma</p> Signup and view all the answers

    What is the primary cause of dehydration as outlined in the content?

    <p>External water loss due to vomiting or diarrhoea</p> Signup and view all the answers

    Which condition is characterized by a normal or decreased level of plasma proteins despite a decrease in plasma volume?

    <p>Haemoconcentration</p> Signup and view all the answers

    What differentiates lymphoid cells from myeloid cells?

    <p>The types of leukemias they produce</p> Signup and view all the answers

    Which statement about the prognosis of inappropriate secondary absolute polycythaemia is correct?

    <p>The prognosis is variable and often guarded.</p> Signup and view all the answers

    What is a common cause of secondary absolute polycythaemia?

    <p>Chronic pulmonary disease</p> Signup and view all the answers

    Which of the following describes absolute polycythaemia vera?

    <p>Myeloproliferative condition with normal or decreased erythropoietin levels</p> Signup and view all the answers

    What is a characteristic feature of plasma cell myeloma?

    <p>It leads to focal osteolytic lesions.</p> Signup and view all the answers

    Which of the following conditions is commonly associated with FeLV positivity?

    <p>Myeloproliferative disorders</p> Signup and view all the answers

    What does the Red Blood Cell Count (RBC) measure?

    <p>Total number of erythrocytes per unit volume of blood</p> Signup and view all the answers

    What physiological response occurs in animals during fear and excitement that affects hematocrit levels?

    <p>Splenic contraction leading to the release of red blood cells</p> Signup and view all the answers

    Inappropriate secondary polycythaemia is associated with elevated levels of erythropoietin. What is a likely underlying cause?

    <p>Renal lesions or tumours</p> Signup and view all the answers

    In which type of aspirate is plasma cell myeloma least likely to show significant results?

    <p>Lymph node aspirate</p> Signup and view all the answers

    How is the White Blood Cell (WBC) count expressed in SI units?

    <p>n.nn × 109/L</p> Signup and view all the answers

    What is the purpose of calculating the corrected WBC?

    <p>To account for falsely elevated leukocyte counts</p> Signup and view all the answers

    Which clinical sign is indicative of dehydration in animals?

    <p>Increased plasma protein concentration</p> Signup and view all the answers

    How is hyperglobulinaemia clinically significant in plasma cell myeloma?

    <p>It contributes to the symptoms observed.</p> Signup and view all the answers

    What effect does living at a high altitude have on erythropoietin levels?

    <p>Stimulates increased erythropoietin secretion</p> Signup and view all the answers

    What is the method for determining the relative differential leukocyte count?

    <p>Counting a sample of leukocytes and classifying each</p> Signup and view all the answers

    Which type of leukaemia typically shows an increased white cell count (WCC) and prominent bone marrow changes?

    <p>Acute myeloid leukaemia</p> Signup and view all the answers

    Which disorder typically results in a decreased count across all cell types?

    <p>Myelodysplastic syndrome</p> Signup and view all the answers

    To calculate the absolute differential leukocyte count, which formula is used?

    <p>Total WBC × percentage of each leukocyte type</p> Signup and view all the answers

    What is the significance of reporting the percentage of nucleated erythrocytes?

    <p>It is crucial for calculating corrected WBC</p> Signup and view all the answers

    What is true regarding the diagnostic sensitivity of a blood smear for lymphoid leukaemia?

    <p>It has a high sensitivity with an increase in white blood cells.</p> Signup and view all the answers

    Which condition is characterized by abnormal proliferation of non-lymphoid haemopoietic cells?

    <p>Myeloproliferative disorders</p> Signup and view all the answers

    Why is the relative differential leukocyte count necessary?

    <p>It is used in the calculation of absolute differential counts</p> Signup and view all the answers

    What happens to the total WBC count if there is a high number of nucleated erythrocytes?

    <p>It will be falsely elevated</p> Signup and view all the answers

    Study Notes

    Haematology 410 - Clinical Pathology

    • Haematology is the study of the haematopoietic system, which includes erythron, leukon and haemostasis
    • Blood comprises plasma, erythrocytes (red blood cells), leukocytes (white blood cells) and platelets
    • The haematopoietic system is distributed throughout the body (bone marrow, lymphoid organs, liver) and acts as a transport and host defence system
    • Erythron represents red cells and precursors (stem cells in the bone morrow) with oxygen transport as its major function
    • Leukon represents white blood cells and their role is a defence mechanism
    • Haemostasis is a complex interaction between blood vessels, platelets and clotting factors to form and dissolve blood clots as needed
    • Red blood cells transport oxygen via haemoglobin; their membrane composed of lipids, proteins and carbohydrates regulates cell shape and integrity
    • Erythrocyte morphology (shape, size, central pallor) varies amongst species
    • Reticulocytes (immature red blood cells) are a sign of regenerative response to anaemia

    Haematological Methods

    • Quantify cells using a haemocytometer (manual) or automated electronic cell counters
    • Impedance counting (e.g., Heska) uses electrical conductivity to measure cell size; may not accurately measure cells of certain sizes (e.g., goats, sheep)
    • Optical/laser flow cell cytometers (e.g., ADVIA) measures cell light scattering properties, more accurate but needs pre-setting for each species
    • Red Corpuscle Count (RCC)/Red blood cell count (RBC): measure of total erythrocytes per unit volume (litres) of blood
    • White Blood Cell (WBC) count: measure total leukocytes per unit volume (litres) of blood
    • Corrected WBC accounts for nucleated erythrocytes in the differential count

    Quantitative Haematological Methods

    • Differential leukocyte count evaluates the relative proportions of different white blood cell types in circulation.
    • Central venous blood is preferred; mixes blood in tubes before use and avoid letting stand too long for optimal cell evaluation
    • Various counting patterns exist; neutrophils are usually more concentrated at the smear's edges, lymphocytes mostly in red cell area, and monocytes dispersed throughout, with activated monocytes and eosinophils more on the feathered edge
    • Modified Battlement method is the most common technique amongst labs

    Calculation of Absolute Differential Counts

    • The relative count (%) of each leukocyte type is multiplied by the total WBC count to calculate absolute counts, for example Neutrophils 30% and Total WBC 50.0 × 109/L gives 15.0 × 109/L- Absolute Neutrophil Count.

    Platelet Count

    • Used to quantify platelets per unit volume of blood
    • Haemocytometer or electronic counters are methods to measure platelet counts.

    Haematocrit (Hct) Determination

    • Represents the percentage of blood volume filled by erythrocytes, measurement of oxygen-carrying capacity.
    • The process involves centrifuging blood to separate cells and plasma layers with the resultant "buffy coat" layer of platelets
    • PCV and Hct is often used synonymously. These are calculated differently

    Erythrocyte Indices

    • Mean Corpuscular Volume (MCV): Average volume of circulating erythrocytes; provides an indication of the average size of red blood cells
    • Mean Corpuscular Haemoglobin Concentration (MCHC): Average concentration of haemoglobin in the red blood cell; provides an indication of the average concentration of haemoglobin in red blood cells

    Reticulocyte Count

    • Reticulocytes are immature red blood cells containing residual RNA
    • Measured to determine the degree of red blood cell regeneration in response to anaemia
    • Blood smear evaluation using a supravital stain counts the reticulocytes within viewing fields
    • Reticulocytes are more concentrated during blood loss to maintain a certain oxygen carrying capacity

    The Erythron

    • Rouleaux: stacks of erythrocytes resembling coins, usually due to altered surface membrane charge and changes in plasma protein concentration
    • Agglutination: clumping of erythrocytes due to antibodies binding (e.g., in Immune Mediated Haemolytic Anaemia-IMHA)
    • In-saline agglutination: test to differentiate rouleaux and agglutination

    Erythrocyte Evaluation on a Blood Smear

    • Anisocytosis: variation in size of erythrocytes (scored 1+ to 6+)
    • Macrocytes: larger than normal erythrocytes, possibly due to reticulocytosis, or macrocytosis
    • Microcytes: smaller than normal erythrocytes, possibly due to iron deficiency anaemia, inflammatory disorder, or spherocytes (in immune-mediated haemolytic anaemia) or in disorders of haemoglobin production

    Inclusions

    • Nucleated erythrocytes: increased numbers observed in regenerative anaemias, lead poisoning

    The Leukon (White Blood Cells)

    • Neutrophils: Circulating and marginated pools; move slowly in circulation due to adhesion molecules; important in inflammatory reactions and bone marrow replenishment
    • Eosinophils: Circulating and marginal pool; primarily involved in defence against helminth parasites and allergic reactions
    • Monocytes: Circulate a limited time; move to tissues, where they differentiate into macrophages; involved in phagocytosis
    • Lymphocytes: Re-circulate; originate in secondary lymphoid tissues; part of adaptive immune response

    Inflammation and Leukograms

    • Inflammation is the most important response of blood leukocytes
    • Neutrophilia with a left shift is a classical sign of inflammation
    • Lymphopenia is common in inflammatory reactions
    • Monocytosis varies depending on the specifics of the inflammatory reaction
    • Eosinophilia occurs with parasite reactions

    Haematological Responses and Disorders: Anaemia

    • Anaemia involves a decrease in erythrocyte counts; may be relative or absolute
    • Clinical signs include lethargy, pallor, tachycardia, tachypnoea and haemoglobinuria
    • Anaemia can be classified according to MCV/MCHC, bone marrow response, or major pathophysiologic mechanism
    • Regenerative anaemia: bone marrow is actively producing red blood cells
    • Non-regenerative anaemia: bone marrow doesn't respond promptly to increase red blood cell production

    Haematological Responses and Disorders: Polycythaemia

    • Polycythaemia is an increase in erythrocyte concentration
    • Dehydration due to decreased plasma volume
    • Haemoconcentration: decreased plasma volume and increased plasma protein

    Haemoproliferative Disorders

    • These include Lymphomas and Leukaemias
    • Lymphomas - cancer of the lymph tissue, originating from lymph nodes
    • Leukaemias - cancer of the bone marrow, affecting WBCs
    • Diagnosis using bone marrow aspirate, blood smear, WBC counts, and lymph node aspirate

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    CLP 410 Haematology Notes 2023 PDF

    Description

    Explore the fundamentals of haematology in this quiz covering the haematopoietic system, blood composition, and the roles of erythron, leukon, and haemostasis. Understand how these components work together for oxygen transport and immune defense. Test your knowledge on the intricacies of blood cell morphology and functions.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser