Red Cell Characteristics seen in different types of anaemia

1. Red Cell Characteristics seen in different types of anaemia Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

2. Sickle Cell Disease Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

3. Anaemias of Deficient Red Cell Production Iron deficiency anaemia Megaloblastic anaemia (Vitamin B12 deficiency and folic acid deficiency) Anaplastic anaemia

4. Polycythemia Represents an abnormally high total red blood cell count with a hemocrit greater than 50 percent. Relative or Absolute Primary polycythemia (polycythemia vera) is a proliferative disease of the bone marrow with an absolute increase in total red blood cell mass accompanied by elevated white blood cell and platelet counts. Secondary polycythemia results from increased erythropoietin levels caused by hypoxic conditions such as chronic heart and lung disease. Many of the manifestations of polycythemia are related to increased blood volume and viscosity that lead to hypertension and stagnation of blood flow.

5. Assess Your Understanding Explain the cause of sickling in sickle cell disease. Cite common causes of iron deficiency anaemia in infancy, adolescence, and adulthood. Mature RBCs have a life span of approximately __________ months. The ______________ measures the volume of red cell mass in 100ml of plasma volume. _____________ is defined as an abnormally low number of circulating RBC’s or level of haemoglobin.

6. Disorders of the Immune Response

7. Hypersensitivity Disorders Result from immune responses to exogenous and endogenous antigens that produce inflammation and cause tissue damage. Type I mediated hypersensitivity is an IgE-mediated response that leads to the release of inflammatory mediators from sensitized mast cells. Type II involve an antibody mediated response against cell surface or extracellular matrix antigens that results in complement mediated phagocytosis, inflammation and cell injury, or abnormal physiological responses without cell injury. Type III disorders responses result from the generation of circulating antigen-antibody complexes that activate complement resulting in recruitment and activation of inflammatory cells that release tissue-damaging products. Type IV disorders involve tissue damage in which cell-mediated immune responses with sensitized T lymphocytes cause cell and tissue injury.

8. Type I Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

9. Type II Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

10. Type III Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

11. Type IV Porth, C.M. 2011. Essentials of Pathophysiology, 3rd edn.

12. Graft-Versus-Host-Disease Occurs when immunologically competent cells or precursors are transplanted into recipients who are immunologically compromised. Three basic requirements are necessary for GVHD to develop: The transplant must be a functional cellular immune component The recipient tissue must bear antigens foreign to the donor tissue. Recipient immunity must be compromised to the point that it cannot destroy the transplanted cells.

13. Autoimmune Disease Represent a group of disorders that are caused by a breakdown in the ability of the immune system to differentiate between self and non-self antigens. Autoimmune diseases can affect almost any cell or tissue in the body. Some autoimmune disorders such as Hashimoto’s thyroiditis, are tissue specific, whereas others such as SLE, affect multiple organs and symptoms.

14. Immunologic Intolerance Immunologic intolerance is the ability of the immune system to differentiate self from non-self. It results from central and peripheral mechanisms that delete self-reactive immune cells that cause autoimmunity or render their response ineffective in destroying self-cells and self-tissue. Central intolerance involves the elimination of self-reactive T and B cells in the central lymphoid organs. Self reactive T cells are deleted in the thymus and self reactive B cells in the bone marrow. Peripheral intolerance derives from the deletion or inactivation of self reactive T and B cells that escaped deletion in the central lymphoid organs.

15. Assess Your Understanding Allergic ___________ is characterised by symptoms of sneezing, itching and watery discharge from the nose and eyes. Individuals with _________________ allergic conditions tend to have high serum levels of IgE and increased numbers of basophils and mast cells. Loss of self tolerance with development of _____________________ is characteristic of a number of autoimmune disorders. Explain how a patient can become sensitized to an allergen in a type I hypersensitivity reaction.