Pathology Quiz 2

Plasma

Liquid portion of circulating blood.

Haemopoiesis

Process of formation and development of blood cells.

Three main types of blood cells

Erythrocytes, Leucocytes, and Thrombocytes.

The first phase of haematopoiesis begins in which organ?

Yolk sac

Main site of haematopoiesis in the adult human

Marrow of the flat bones and the proximal ends of long bones.

Major component of a RBC

Haemoglobin

Number of oxygen molecules one molecule of haemoglobin can carry

Four

Haemopoietic cells that can differentiate into different cell types

Progenitor cells.

Physiological programmed cell death

Apoptosis.

Where macrophages remove old erythrocytes

Spleen.

Large cells from which platelets arise

Megakaryocytes.

Platelet adhesion

Platelets sticking to substances such as subendothelial collagen.

Erythropoietin (EPO)

Hormone produced in the kidney which controls the production of RBC.

Haemoglobin

Main cytoplasmic component of the mature RBC accounting for ~90% of the cell’s contents.

Platelets

Cell fragments that arise in the bone marrow from large cells called Megakaryocytes, via a process called thrombopoiesis.

Information required to label specimens

Full name, date of birth, and hospital UR number.

Responsibilities of specimen reception staff

Check for correct specimens and proper labeling, enter patient demographics, process specimens, and prepare specimens for specialized testing.

Common pathology tests for blood specimens

Full blood count (FBC), Coagulation Profile (coags), Erythrocyte Sedimentation Rate (ESR)

Responsibilities of the scientist in the haematology laboratory

Check patient details, specimen integrity, load specimens onto analysers, and inform medical staff of critically abnormal results.

Erythrocyte Sedimentation Rate (ESR)

The rate at which red blood cells sediment in a period of one hour and is a non-specific measure of inflammation.

Overriding standard precaution in the lab

All blood and body fluids should be handled as though they are potential carriers of infectious disease.

Standard PPE

Lab coat, Disposable gloves, Eye protection, Covered footwear.

Duty of all laboratory personnel

Ensure that the confidentiality of all information relating to patients is maintained at all times.

Oncogene

A mutated gene capable of causing malignant transformation of normal cells.

Haemostasis

The process by which a series of platelet, endothelial cell, and plasma enzyme systems work to minimize blood loss from a damaged blood vessel.

Thrombocytopenia

A condition characterized by a deficiency of platelets in the blood, leading to a tendency to bleed and bruise easily.

Splenomegaly

Enlargement of the spleen.

Abnormal sequestration of PLT

Refers to the abnormal sequestration (holding) of platelets, leading to thrombocytopenia.

Haematocrit

The volume of packed red blood cells that occupies a given volume of whole blood; also known as packed cell volume (PCV).

Erythrocyte Sedimentation Rate (ESR)

A general screening test used to detect inflammation in the body.

ESR Measurement

The distance (in mm) that red blood cells fall in 1 hour when anticoagulated blood is allowed to stand undisturbed at room temperature.

Haemoglobin level

The most important and most frequently requested test in the haematology lab

Cyanmethaemoglobin method

Reference method for haemoglobin determination

RBC Replenishment

The process by which the bone marrow continually replaces the supply of red blood cells.

Haematinics

Nutritional factors required for adequate RBC production, including iron, Vitamin B12, and folate.

Insufficient Erythropoiesis

A decrease in the production of red blood cells in the bone marrow.

Ineffective Erythropoiesis

Production of defective erythroid progenitor cells, often destroyed in the bone marrow.

Haemolysis

Disintegration of a cell by rupture of the cell wall or membrane.

Haemolysis

Increased RBC destruction.

Reticulocytes

Immature RBC that lack a nucleus but still contain residual RNA.

Innate Immunity

Non-specific and relatively rapid immunity involving monocytes and granulocytes.

Adaptive Immunity

Highly specific immunity involving antibody production by B lymphocytes and direct killing by T lymphocytes.

Diapedesis

The ability of neutrophils to extravasate and enter tissues.

Chemotaxis

The process by which neutrophils are recruited to a site of infection.

Eosinophils

Cells that destroy helminths (worms) and parasites, associated with allergic disorders.

Basophils

Granulocytes associated with hypersensitivity (allergic) reactions and autoimmune diseases.

Monocytes

Cells that move into tissues and mature into macrophages, involved in phagocytosis and antigen presentation.

Phagocytosis

Ingestion of foreign particles, including bacteria.

Hereditary Spherocytosis

An inherited RBC membrane defect leading to transfusion dependent haemolytic anaemia.

Sickle Cell Anaemia

An inherited haemoglobin defect leading to transfusion dependent haemolytic anaemia.

Vitamin B12 or Folate Deficiency

Oval macrocytosis and hypersegmented neutrophils on a blood film are signs of…