Lecture – 3 Dr. Zahoor Ali Shaikh ANEMIA POLYCYTHEMIA Lecture – 3 Dr. Zahoor Ali Shaikh

ANEMIA What is Anemia? Anemia means - Decreased hemoglobin - Decreased RBC count - Decreased Hematocrit [PCV] Therefore, decreased O2 carrying capacity of blood.

CAUSES OF ANEMIA Nutritional Anemia It is caused by dietary deficiency of factors needed for Erythropoiesis. 1. Dietary Deficiency of Iron Iron deficiency anemia is called microcytic hypochromic anemia as RBC is small with less Hemoglobin.

Nutritional Anemia 2. Megloblastic Anemia It is due to deficiency of vitamin B12 or folic acid. Vitamin B12 is essential for normal RBC maturation. Vitamin B12 deficiency leads to Megloblastic Anemia [RBC size is large].

Anemia Pernicious Anemia - It is due to deficiency of Intrinsic factor produced by Parietal cells of stomach. - Intrinsic factor is necessary for absorption of Vitamin B12. - Vitamin B12 is absorbed from intestinal tract [terminal ileum] when Vitamin B12 is bound to intrinsic factor. - Pernicious Anemia is megloblastic anemia.

ANEMIA 3. Aplastic Anemia It is caused by failure of bone marrow to produce RBC even though all necessary nutrients for Erythropoiesis are available. Causes of Aplastic Anemia -Excessive exposure to X-ray -Exposure to radiation, e.g. bomb blast -Chemotherapy for Cancer -Drugs

ANEMIA 4. Hemolytic Anemia It is caused by rupture [breakdown] of RBC. Causes of Hemolytic Anemia -Malaria -Sickle Cell Anemia [Hemoglobin β chain is defective where valine replaces glutamate at position 6 in this amino acid chain].RBC is sickle shaped -Mismatched blood transfusion -Drugs

ANEMIA 5. Renal Anemia Anemia in Renal [kidney] disease is due to decreased Erythropoietin secretion from the kidney. It leads to decreased RBC production.

ANEMIA 6 .Hemorrhagic Anemia - It is caused by losing a lot of blood. - Acute Loss of blood e.g. car accident. - Chronic Loss of blood e.g. bleeding peptic ulcer, excessive menstrual flow.

ANEMIA How to diagnose microcytic hypochromic anemia [iron deficiency] and macrocytic [megloblastic] which is vitamin B12 deficiency anemia? We see Hemoglobin, RBC, PCV [Hematocrit] MCV [Mean Cell Volume] MCH [Mean Concentration of Hemoglobin] MCHC [Mean Cell Hemoglobin Concentration]

ANEMIA We will define MCV, MCH, MCHC. MCV – it is the volume of average RBC - Normal MCV = 90 fL or 90 μ3 [MCV > 95 fL are called macrocyte] [MCV < 80 fL are called microcyte] MCH – it is mean concentration of Hemoglobin in each RBC. - Normal MCH = 30 picogram [pg] MCHC – it is hemoglobin present per 100ml of RBC. - Normal MCHC = 30 gram/100ml of RBC

Microcytic Hypochromic Anemia Or Iron Deficiency Anemia In iron deficiency anemia Hemoglobin RBC Hematocrit MCV MCH MCHC

ANEMIA Macrocytic [Megloblastic] Anemia Vitamin B12 or folic acid deficiency Hemoglobin RBC Hematocrit MCV MCH Normal MCHC Normal It is called Macrocytic Normochromic Anemia.

NORMAL VALUE & FORMULA FOR CALCULATION OF MCV, MCH, MCHC

CLINICAL EXAMPLE A patient came with a history of fatigue, weakness. His blood analysis was done RBC count 3.6 × 106 / mm3 Hb concentration 7.0 g / 100ml PCV 25% MCV 69.4 fL [femtoliter] Normal 90 fL MCH 19.4 pg [picogram] Normal 30 pg MCHC 28 g / dl Normal 34 g/dl What is Diagnosis ? Microcytic Hypochromic Anemia [Iron deficiency Anemia]

POLYCYTHEMIA Polycythemia is characterized by increased number of RBC and increased Hematocrit. Types of Polycythemia 1. Primary Polycythemia 2. Secondary Polycythemia

Primary Polycythemia Primary Polycythemia is tumor like condition of bone marrow, where, there is increased production of RBC. RBC count may reach 11 million/mm3 (normal is 5 million cells/mm3) . Hematocrit may be 70-80% [normal 42-45%].

Primary Polycythemia Side Effects - As there is increased viscosity of blood, it causes blood to flow very slowly, which may reduce O2 delivery to tissues. - Increased viscosity causes increased peripheral resistance which may cause increased blood pressure.

Secondary Polycythemia Secondary Polycythemia is due to decreased O2 delivery to the tissues. It occurs in people living at high altitude as O2 available in the air is less. It occurs in people with chronic lung disease called Cardiac [heart] failure due to decreased O2 delivery to the tissues. RBC count may be 6 to 8 million/mm3.

Relative Polycythemia Relative Polycythemia occurs when there is body fluid loss e.g. diarrhea, heavy sweating. There is body fluid loss, but no loss of erythrocytes. This is not true Polycythemia as RBC are not increased, but only plasma volume is decreased. As RBC are concentrated in small plasma volume, this condition is called Relative Polycythemia.

APPLIED Effect of Anemia In Anemia, blood viscosity is decreased to 1.5 times of water [normal viscosity 2.5 – 3 times of water]. Therefore, there is decreased peripheral resistance, it causes increased blood flow and increased venous return to heart, therefore, increased cardiac output. Anemia causes hypoxia [decrease O2 delivery to tissues], therefore, increased cardiac output.

APPLIED Effect of Polycythemia In Polycythemia, there is increased viscosity, therefore, blood flow is sluggish [slow]. Increased viscosity leads to increased peripheral resistance, therefore, increased blood pressure can occur [in 1/3rd of polycythemic people].

WHAT YOU SHOULD KNOW FROM THIS LECTURE What is Anemia ? Types of Anemia Difference between Microcytic Hypochromic and Macrocytic Normochromic Anemia Normal Values for RBC, Hb, HCT [PCV], MCV, MCH, MCHC Polycythemia Definition Difference between Primary Secondary Polycythemia Effect of Anemia and Polycythemia on body

THANK YOU