pathologocal and physiological Disoders of RBCs and WBCs.pptx

the different disorders that affect different blood cells and the pathogenesis of those disorders

1. BLOOD AND BODY FLUIDS

2. ANAEMIA Anaemia is defined as a haemoglobin concentration in blood below the lower limit of the normal range for the age and sex of the individual. In adults, the lower extreme of the normal haemoglobin is taken as 13.0 g/dl for males and 11.5 g/dl for females

3. CLASSIFICATION OF ANEMIA Anemia is classified by two methods: Morphological classification Etiological classification

4. Morphological classification

5. ETIOLOGICAL classification On the basis of etiology (study of cause or origin ), anemia is divided into five types Hemorrhagic anemia Hemolytic anemia Nutrition deficiency anemia Aplastic anemia Anemia of chronic diseases

6. Hemorrhagic Anemia After rapid hemorrhage, the body replaces the fluid portion of the plasma in 1 to 3 days, but this leaves a low concentration of red blood cells. If a second hemorrhage does not occur, the red blood cell concentration usually returns to normal within 3 to 6 weeks .

7. Hemorrhagic Anemia cont’d In chronic blood loss, a person frequently cannot absorb enough iron from the intestines to form hemoglobin as rapidly as it is lost Red cells are then produced that are much smaller than normal and have too little hemoglobin inside them, giving rise to microcytic, hypochromic anemia

8. Hemolytic Anemia Hemolysis means destruction of RBCs Anemia due to excessive hemolysis which is not compensated by increased RBC production is called hemolytic anemia Extrinsic hemolytic anemia Intrinsic hemolytic anemia

9. Extrinsic hemolytic anemia It is the type of anemia caused by destruction of RBCs by external factors Healthy RBCs are hemolized by factors outside the blood cells such as antibodies, chemicals and drugs. Extrinsic hemolytic anemia is also called autoimmune hemolytic anemia

10. Extrinsic hemolytic anemia cont’d Common causes of external hemolytic anemia Liver failure Renal disorder Infections like hepatitis, malaria and septicemia Drugs such as penicillin, antimalarial drugs and sulfa drugs Poisoning by chemical substances like lead, coal and tar

11. Erythroblastosis Fetalis In erythroblastosis fetalis , Rh-positive red blood cells in the fetus are attacked by antibodies from an Rh-negative mother These antibodies make the Rh-positive cells fragile, leading to rapid rupture and causing the child to be born with serious anemia.

12. Erythroblastosis Fetalis cont’d The extremely rapid formation of new red cells to make up for the destroyed cells in erythroblastosis fetalis causes a large number of early blast forms of red cells to be released from the bone marrow into the blood.

13. Intrinsic hemolytic anemia It is a type of anemia caused by destruction of RBCs because of the defective RBCs. Intrinsic hemolytic anemia is often inherited it includes: Sickle cell anemia Thalassemia

14. Sickle Cell Anemia In sickle cell anemia, the cells have an abnormal type of hemoglobin called hemoglobin S , containing faulty beta chains in the hemoglobin molecule

15. Sickle cell anemia cont’d When this hemoglobin is exposed to low concentrations of oxygen, it precipitates into long crystals inside the red blood cell These crystals elongate the cell and give it the appearance of a sickle rather than a biconcave disc

16. Sickle cell anemia cont’d The precipitated hemoglobin also damages the cell membrane, so that the cells become highly fragile , leading to serious anemia.

17. Sickle c ell anemia cont’d Such patients frequently experience a vicious circle of events called a sickle cell disease “crisis,” in which low oxygen tension in the tissues causes sickling, which leads to ruptured red cells, which causes a further decrease in oxygen tension and still more sickling and red cell destruction

18. Sickle c ell anemia cont’d Once the process starts, it progresses rapidly, eventuating in a serious decrease in red blood cells within a few hours and, often, death.

19. Thalassemia In thalassemia, the number of α and β polypeptide chains is unequal because of defective synthesis of globin genes

20. Thalassemia cont’d This causes the precipitation of the polypeptide chains in the immature RBCs, leading to disturbance in erythropoiesis. The precipitation also occurs in mature red cells, resulting in hemolysis

21. NUTRITION DEFICIENCY ANEMIA Anemia that occurs due to deficiency of a nutritive substance necessary for erythropoiesis is called nutrition deficiency anemia The substances which are necessary for erythropoiesis are iron, proteins and vitamins like C , B12 and folic acid.

22. Iron deficiency anemia Iron deficiency anemia develops due to inadequate availability of iron for hemoglobin synthesis. RBCs are microcytic and hypochromic. Etiology Loss of blood Decreased intake of iron Poor absorption of iron from intestine Increased demand for iron in conditions like growth and pregnancy.

23. Iron deficiency anemia cont’d Signs and symptoms Brittle nails Spoon shaped nails (koilonychias) Brittle hair Atrophy of papilla in tongue Dysphagia (difficulty in swallowing )

24. Protein deficiency anemia Due to deficiency of proteins, the synthesis of hemoglobin is reduced. The RBCs are macrocytic and hypochromic

25. Pernicious anemia It is also called Addison’s anemia Pernicious anemia is the anemia due to deficiency of vitamin B12 It is due to atrophy of the gastric mucosa

26. Pernicious anemia Atrophy of the gastric mucosa results in decreased production of intrinsic factor and poor absorption of vitamin B12, which is the maturation factor for RBC. RBCs are larger (macrocytic) and immature with almost normal or slightly low hemoglobin level (normochromic/hypochromic)

27. APLASTIC ANEMIA Aplastic anemia is due to the disorder of red bone marrow Red bone marrow is reduced and replaced by fatty tissues In aplastic anemia, the RBCs are normocytic and normochromic

28. Aplastic Anemia cont’d Bone marrow disorder occurs in the following conditions: Repeated exposure to X – ray or gamma ray radiation . Presence of bacterial toxins, quinine, gold salts, benzene , radium, etc. Tuberculosis . Viral infections like hepatitis and HIV infections

29. ANEMIA OF CHRONIC DISEASES Anemia of chronic diseases is characterized by short lifespan of RBCs, caused by disturbance in iron metabolism or resistance to erythropoietin action. RBCs are normocytic and normochromic

30. Anemia of Chronic Diseases cont’d Chronic renal failure, in which the erythropoietin secretion decreases Noninfectious inflammatory diseases such as rheumatoid arthritis Chronic infections like tuberculosis and abscess Neoplastic disorders such as Hodgkin’s disease and cancer of lung and breast

31. Symptoms of anemia Tiredness Easy fatiguability Generalised muscular weakness Lethargy and headache

32. Symptoms of anemia cont’d In older patients, there may be symptoms of cardiac failure Angina pectoris Intermittent claudication Confusion Visual disturbances

33. Signs of anemia Color of the skin and mucous membrane becomes pale in buccal , pharyngeal mucous membrane, conjunctivae, lips, ear lobes , palm and nail bed. Skin looses the elasticity and becomes thin and dry. Thinning , loss and early grayness of hair occur. The nails become brittle and easily breakable .

34. Signs of anemia cont’d There is an increase in heart rate (tachycardia) and cardiac output. Heart is dilated There is an increase in rate and force of respiration. It leads to breathlessness and dyspnea

35. Signs of anemia cont’d Anorexia, nausea, vomiting, abdominal discomfort and constipation In pernicious anemia, there is atrophy of papillae in tongue and necrotic lesions appear in mouth and pharynx In females, disturbances such as menorrhagia, oligomenorrhea or amenorrhea

36. DISORDERS OF WHITE BLOOD CELLS

37. DISORDERS OF WHITE BLOOD CELLS White blood cells also called leucocytes are cells of the immune system that are involved in protecting the body against infectious disease and foreign invaders All WBCs are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells

38. Disorders of WBCs cont’d Leukocytes are found throught the body, including the blood and lymphatic system They are of two types: Granulocytes Agranulocytes

39. Disorders of WBCs cont’d Some Physiological factors may cause variations in the number of WBCs Age Sex Diurnal variations Exercise Emotional conditions Pregnancy Sleep

40. Disorders of WBCs cont’d Disorders of blood cells Leukocytosis Agranulocytosis Neutropenia Leukemias

41. LEUKOCYTOSIS Leukocytosis is an abnormal increase in the number of circulating WBCs Its a manifestation of the body’s reaction to a pathological situation

42. Leukocytosis cont’d Non pathological causes of leukocytosis include Exercise Convulsions such as epilepsy Emotional stress Pregnancy Anesthesia Epinephrine administration

43. Leukocytosis cont’d Types of leukocytosis Neutrophilia Lymphocytosis Monocytosis Eosinophilia basophilia

44. Neutrophilia Neutrophilia is an increase in the number of neutrophils Normal range 1,500 – 8,000/ μ L

45. Neutrophilia cont’d Physiologic causes of neutrophilia New borns During labor After exercise After convulsions

46. Nuetrophilia cont’d Pathological causes of nuetrophilia Acute infections especially pyogenic bacterial infections, viruses and parasites Inflammatory conditions such as gout, burns, vascular diseases and hypersensitivity reactions Intoxications such as uremia

47. Nuetrophilia cont’d Poisoning by chemicals and drugs such as lead and mercury Acute hemorrhage Acute hemolysis Polycythemia Myelotic leukemia

48. Eosinophilia Eosinophilia is an increase in the number of eosinophils in blood It can also be defined as a condition in which the eosinophil count in the peripheral blood exceeds 500/ μ L or 5.0×10 8 /l

49. Eosinophilia It occurrs in response to some allergens, drugs, parasites and in some types of leukemia

50. Eosinophilia cont’d Aetiology Allergic disorders such as bronchial asthma and hay fever Skin diseases such as pemphigus , erythema multiforme and scarlet fever Parasitic infections such as malaria

51. Eosinophilia – aetiology cont’d Diseases of the hemopoietic system such as chronic myeloid leukemia, polycythemia vera , hodgkins disease and pernicious anemia Following irradiation Sarcoidosis Rheumatoid arthritis

52. Basophilia This is a condition of having greater than 100/ μ L basophils in peripheral blood

53. Basophilia cont’d Aetiology Splenectomy Blood diseases such as polycythemia vera , hodgkin’s anemia and chronic myelogenous leukemia (CML) Infections such as smallpox and chicken pox After injection of foreign protein

54. Lymphocytosis Lymphocytosis  is an increase in the number of lymphocytes in the blood In adults, lymphocytosis is present when the lymphocyte count is greater than 4000/ μ L  (4.0 x 10 9 /L), in older children greater than 7000/ μ L and in infants greater than 9000/ μ L

55. Lymphocytosis cont’d Etiology Acute infections such as infectious mononucleosis Chronic infections such as tuberculosis, syphilis, lymphocytic leukemia and lymphosarcoma Hemopoietic disorders such as lymphocytosis , Mumps, german measles and thyrotoxicosis

56. Monocytosis Monocytosis  is an increase in the number of  monocytes circulating in the blood. Normal range in males: 0.2-0.8 x 10 3 / μ L Monocytes give rise to macrophages and dendritic cells in the immune system. Monocytosis has sometimes been called mononucleosis

57. Monocytosis cont’d Etiology Bacterial infections such as tuberculosis, Subacute bacterial endocarditis and syphilis Protozoal and rickettsial infections such as malaria, typhus and multiple myeloma

58. Monocytosis cont’d Granulomatous disease such as sarcoidosis , ulcerative colitis Collagen vascular disease such as lupus erythematosus , rhematoid arthritis

59. Agranulocytosis Disease involving WBCs and is characterized by decrease in the number of circulating granulocytes Agranulocytosis , neutropenia , and granulocytopenia are used interchangeably to denote reduced number of leukocytes

60. Agranulocytosis cont’d Types Primary agranulocytosis – whose etiology is unknown Secondary agranulocytosis – with a known etiology

61. Agranulocytosis cont’d Etiology Antineoplastics Antibiotics Anticonvulsants Antiinflammatories Antithyroid agents Duiretics Phenothiazines

62. Agranulocytosis cont’d Signs and symptoms May be asymptomatic Sudden fever  Rigors and sore throat  Infection of any organ may progress rapidly e.g. pneumonia, UTIs  Sepsis may also progress rapidly Regional lymphadenitis

63. Leukemia Leukemia is a disease characterised by the progressive overproduction of WBCs which usually appear in the circulating blood in an immature form

64. Leukemia cont’d Leukemic cells multiply at the expense of normal hematopoietic cell lines, resulting in marrow failure, altered blood cell counts, and, when untreated, death from infection, bleeding, or both

65. Leukemia cont’d Classification Lymphoid (lymphoblastic, lymphocytic) leukemia This involves the lymphocytic series

66. Leukemia cont’d Classification cont’d Myeloid ( myelogenous ) leukemia This involves progenital cells that give rise to terminally differentiated cells of the myeloid series (erythrocytes, granulocytes, monocytes and platelets)

67. Leukemia cont’d Classification based on the course of the disease Acute – survival is less than 6 months Sub acute – survival is between acute and chronic Chronic – survival of over 1 year

68. Leukemia cont’d Etiology Chromosome abnormalities Exposure to pesticides, benzene and ionizing radiations Epstein Barr virus (EBV), Human T – cell leukemia virus – 1 (HTLV -1)

69. Leukemia cont’d Clinical features Weaknes Fever and headaches Generalized swelling of lymph nodes

70. Leukemia cont’d Clinical features cont’d Petechial or ecchymotic hemorrhages in the skin and mucous membranes Anemia Spleen, liver and kidney become enlarged owing to leukemia infiltration hemorrhage