Hematology Basics Quiz

Hematology Basics

• Hematology is the study of blood and its components.
• Blood consists of solid components (red blood cells, white blood cells, platelets) and liquid components (plasma).

Red Blood Cells

• Normal red blood cell count (RBC) is 4-6 million/mm3.
• Erythrocytes are another name for red blood cells.
• Hypoxia (low oxygen levels) stimulates red blood cell production, a process called erythropoiesis.
• The lifespan of a red blood cell is 120 days.

Red Blood Cell Production

• Erythropoiesis is the process of red blood cell production.
• Hypoxia stimulates the kidneys to produce erythropoietin.
• Erythropoietin travels to the bone marrow, where it stimulates stem cells to create red blood cells.

Anemia

• Anemia is a condition characterized by a deficiency of red blood cells.
• Anemia results in a decrease in hemoglobin, impacting the blood's oxygen carrying capacity.

Megaloblastic Anemia

• Characterized by large, poorly functioning, immature red blood cells called reticulocytes.
• These reticulocytes fail to mature and die prematurely.
• Megaloblastic anemia is caused by deficiencies in vitamin B12 and/or folic acid.

Pernicious Anemia

• Pernicious anemia is a type of megaloblastic anemia caused by a lack of vitamin B12.
• It can lead to neurological damage if untreated for longer than 6 months.

Causes of Pernicious Anemia

• Diet:
  • Inadequate intake of vitamin B12, commonly from animal products.
  • Vegetarian diets can contribute if not appropriately supplemented.
• Gastrectomy:
  • Surgical removal of the stomach, which produces intrinsic factor.
  • Intrinsic factor is essential for the absorption of vitamin B12 in the ileum.
• Ileostomy:
  • Surgical opening in the ileum, part of the small intestine.
  • This surgery can disrupt the absorption of vitamin B12.

Vitamin B12 Absorption

• Vitamin B12 binds to intrinsic factor in the stomach.
• The complex of vitamin B12 and intrinsic factor is absorbed in the ileum.
• Any disruption in this process can lead to pernicious anemia.

Signs and Symptoms of Pernicious Anemia

• Fatigue: Individuals feel tired easily, even with minimal effort.
• Anorexia: Loss of appetite.
• Weight loss.
• Palor: A pale complexion due to the low red blood cell count.
• Paralysis: Can occur due to the neurological damage caused by vitamin B12 deficiency.