Hematology: Immunoglobulins, Anaemia, and Laboratory Measurements

Comprehensive vocabulary flashcards covering immunoglobulin structure and types, specific types of anaemia (B12, Folic Acid, Iron deficiency, Sickle cell, Thalassemia), and key laboratory diagnostic terms in hematology.

Immunoglobulins

Glycoproteins produced by plasma cells with a Y-shaped structure composed of four polypeptide chains.

Fab region

The region of an antibody molecule responsible for antigen binding.

Fc region

The region of an antibody molecule responsible for biological actions such as complement activation and placental transfer.

IgG

The most abundant antibody that provides long-term immunity and crosses the placenta to provide passive immunity to the fetus.

IgA

An antibody found in secretions like saliva, tears, and colostrum that provides mucosal immunity.

IgM

The first antibody formed in a primary immune response and a strong activator of the complement system.

IgE

An antibody involved in allergic reactions and defense against parasites.

IgD

An antibody present on the surface of B-cells that assists in B-cell activation.

Pernicious Anaemia

An autoimmune disorder characterized by a deficiency of Vitamin $B_{12}$ due to the absence of intrinsic factor caused by atrophic gastritis.

Folic Acid Deficiency Anaemia

A nutritional deficiency of folic acid typically caused by poor diet or increased requirements, such as during pregnancy, lacking neurological symptoms.

Glossitis

Inflammation of the tongue often present in both Vitamin $B_{12}$ and folic acid deficiency anaemias.

Megaloblastic Anaemia

A condition where RBCs are macrocytic and the bone marrow shows megaloblastic erythropoiesis; caused by Vitamin $B_{12}$ or folic acid deficiency.

Lymph

A fluid that returns tissue fluid and plasma proteins to blood, transports absorbed fats from the intestine, and helps in immune defense.

Osmotic Fragility of RBC

The ability of red blood cells to withstand hemolysis when exposed to hypotonic solutions.

Hereditary Spherocytosis

A condition in which the osmotic fragility of RBCs is increased.

HbF

Fetal hemoglobin.

HbS

Sickle cell hemoglobin, which causes RBCs to become sickle-shaped under low oxygen tension.

Anaemia

A condition characterized by a decrease in hemoglobin concentration below normal for age and sex, reducing the oxygen-carrying capacity of blood.

Microcytic Hypochromic Anaemia

A morphological classification of anaemia where RBCs are smaller than normal with reduced color, seen in iron deficiency and thalassemia.

Aplastic Anaemia

A type of anaemia caused by bone marrow failure, resulting in pancytopenia.

Hemolytic Anaemia

Anaemia resulting from increased RBC destruction, often characterized by jaundice and splenomegaly.

Hemophilia A

A bleeding disorder caused by a deficiency of clotting Factor VIII.

Hemophilia B (Christmas disease)

A bleeding disorder caused by a deficiency of clotting Factor IX.

Purpura

A condition showing purple or reddish spots on skin and mucous membranes that do not blanch on pressure, caused by platelet or blood vessel defects.

Thalassemia

A genetic disorder characterized by defective synthesis of globin chains, leading to microcytic hypochromic anaemia.

Polycythemia Vera

A primary bone marrow disorder caused by hyperplasia, resulting in increased RBCs, WBCs, and platelets.

Bleeding Time (BT)

The time taken for bleeding to stop after standardized skin puncture, reflecting platelet function and capillary integrity.

Clotting Time (CT)

The time taken for blood to clot after being withdrawn from the body, indicating the efficiency of coagulation factors.

Paresthesia

A neurological symptom, such as a tingling sensation, present in Vitamin $B_{12}$ deficiency but absent in folic acid deficiency.