Disorders of blood

Common Disorders of Blood Cells

Definition of Blood Cell Disorder

Blood cell disorder is a disorder which affects the red blood cells, white blood cells and smaller circulating cells called platelets

Common Disorders of the Blood & blood Cells

• Classification of Common Disorders of the Blood Cells
• Anaemia
• o Iron-deficiency anaemia
• o Sickle-cell disease (anaemia)
• o Aplastic anaemia
• o Haemolytic anaemia
• Haemophilia
• Leukaemia

Vitamin K deficiency

Anaemia

Anaemia is a deficiency of red blood cells, or insufficient haemoglobin within the red blood cells.

• There are many different types of anaemia.

Iron-deficiency anaemia

It is caused by a lack of dietary iron, and there is not enough of this mineral to form sufficient haemoglobin.

A person with this type of anaemia may have a normal RBC count and a normal haematocrit, but the haemoglobin level will be below normal.

A deficiency of vitamin B12, which is found only in animal foods in which the RBCs are large, misshapen, and fragile.

Pernicious anaemia is type of anemia due to lack of the intrinsic factor which carries vitamin B12 due to autoimmune destruction of the parietal cells of the stomach lining.

Sickle-cell disease (anaemia)

It is a genetic disorder of haemoglobin (Hb-S), which causes RBCs to sickle, clog capillaries, and rupture.

Even though erythropoiesis is stimulated by the loss of the cells, it cannot keep pace with haemolysis.

Aplastic anaemia

It is suppression of the red bone marrow, with decreased production of RBCs, WBCs, and platelets.

This is a very serious disorder that may be caused by exposure to radiation, certain chemicals such as benzene, or some medications.

• Haemolytic anaemia
• It is any disorder that causes rupture of RBCs before the end of their normal life span.

Sickle-cell anaemia and Rh disease of the new-born are examples.

Another example is malaria, in which a protozoan parasite reproduces in RBCs and destroys them.

Haemolytic anaemias are often characterized by jaundice because of the increased production of bilirubin.

Haemophilia

Haemophilia is an inherited deficiency of clotting factors (VIII, IX and XI) in which bleeding may occur spontaneously or after only minor trauma.

It is X-linked recessive disorder.

Different types of haemophilia have varying degrees of severity, ranging from mild to severe bleeding tendencies.

Haemophilia A (due to deficiency of factor VIII) is more severe than Haemophilia B (-IX ) and Haemophilia C (XI)

Leukaemia

The term leukaemia refers to a group of red bone marrow cancers in which abnormal white blood cells multiply uncontrollably The accumulation of the cancerous white blood cells in red bone marrow interferes with the production of red blood cells, white blood cells, and platelets As a result the oxygen-carrying capacity of the blood is reduced, an individual is more susceptible to infection, and blood clotting is abnormal The cause of most types of leukaemia is unknown

Vitamin K deficiency

Vitamin K is not involved in actual clot formation but it is required for the synthesis of four clotting factors (II,VII,IX, and X) It is a fat-soluble vitamin that can be absorbed through the lining of the intestine and into the blood if absorption of lipids is normal People suffering from disorders that slow absorption of lipids (for example, inadequate release of bile into the small intestine) often experience uncontrolled bleeding as a consequence of vitamin K deficiency

Thrombosis and Embolism

Thrombosis

It is the formation of a clot in the blood that either blocks, or partially blocks a blood vessel.

The thrombus may lead to infarction or death of tissue, due to a blocked blood supply.

The pathologic form of haemostasis is thrombosis. It involves blood clot (thrombus) formation in uninjured vessels or thrombotic occlusion of a vessel after relatively minor injury.

Both haemostasis and thrombosis involve three components: the vascular wall, platelets, and the coagulation cascade.

• Risk factors for thrombosis
• Age (as the age increases so the risk)
• Obesity
• Varicose veins
• Immobility
• Pregnancy
• High estrogenic levels
• Previous history of DVT

Surgery and trauma of the pelvis, lower limbs

Risk factors cont……

• Heart failure
• Recent myocardial infarction
• Lower limb paralysis

Cigarette smoking

Embolism

An embolism is an obstruction in a blood vessel due to a blood clot or other foreign matter that gets stuck while travelling through the bloodstream.

Emboli have moved from the place where they were formed through the bloodstream to another part of the body, where they obstruct an artery and block the flow of blood.

The emboli are usually formed from blood clots but are occasionally comprised of air, fat, or tumour tissue.

• Embolic events can be multiple and small, or single and massive.

They can be life-threatening and require immediate emergency medical care

Key points

Anaemia is a deficiency of red blood cells, or insufficient haemoglobin within the red blood cells.

It is divided into iron deficiency anaemia, sickle cell anaemia, aplastic anaemia and haemolytic anaemia Haemophilia is inherited deficiency of clotting factors

Evaluation

• What is blood cells disorder?
• What is the cause of iron deficiency anaemia?

What is the consequence of vitamin K deficiency?

assignment

Classify common disorders of the blood cell