PATHOLOGY & PATHOPHYSIOLOGY

Transcription

1 PATHOLOGY & PATHOPHYSIOLOGY DISORDERS OF BLOOD

2 DISORDERS OF BLOOD Disorders of Blood Infections Tumours Nutritional disorders Coagulation disorders Congenital disorders Septicaemia Leukemia Iron deficiency anaemia Inadequate platelets Sickle cell anaemia Malaria Pernicious Inadequate clotting factors anaemiars Haemolytic anaemia Vitamin K deficiency

3 TERMINOLOGY penia = too little, e.g. leukopenia cytosis = excess, e.g. leukocytosis

4 ANAEMIA Definition: Low number of RBC s in circulation or a low level of haemoglobin Aetiology: Deficient RBC production Excessive destruction of RBC in the body Excessive loss of RBC from the body

5 ANAEMIA Signs and symptoms: Fatigue Weakness Dyspnoea Faintness Dim vision Pale skin, mucous membranes, conjunctiva and nail beds Tachycardia Palpitations Sometimes angina There may be signs and symptoms of the underlying cause of the deficiency, e.g. if the anaemia is due to iron deficiency there may be sores in the corners of the mouth or spoon shaped nails

6 AETIOLOGY OF ANAEMIA Deficient RBC production: Aplastic anaemia (bone marrow depression), e.g. due to chemotherapy or leukaemia Deficiency of iron or folic acid or vitamin B12. These nutrients are necessary to make haemoglobin and RBC s. Anaemia of chronic diseases

7 AETIOLOGY OF ANAEMIA Excessive destruction of RBC s: Malaria Sickle cell disease Thalassaemia Reactions to medicine Transfusion reactions

8 AETIOLOGY OF ANAEMIA Excessive loss of RBC s: Acute loss of blood Chronic loss of blood, e.g. heavy or too frequent menstruation, peptic ulcers, Crohn s disease, ulcerative colitis, cancer of the GIT, cancer of the bladder

9 DISORDERS OF WHITE BLOOD CELLS

10 LEUKOPENIA Definition: A decrease in the number of white blood cells in the circulating blood Aetiology: Inflammation and infections Drugs, e.g. cancer therapy Neoplasms involving the bone marrow

11 LEUKAEMIA A malignant tumour of the white blood cell precursors in the bone marrow The most common cancer in children Leads to excessive amounts of immature and abnormal WBC s in the blood Decrease in platelets and RBC s

12 LEUKAEMIA Types of leukaemia: Acute myeloid leukaemia Chronic myeloid leukaemia Acute lymphocytic leukaemia Chronic lymphocytic leukaemia

13 LEUKAEMIA Aetiology of leukaemia: Mostly unknown Some factors may contribute: Genetics (slight familial tendency) - an increased incidence in Down s syndrome children Radiation Chemotherapy Infection with HTLV-1 or HTLV-2 virus infection

14 LEUKAEMIA Signs and symptoms of leukaemia: Anaemia Thrombocytopenia Decrease in normal WBC s Bone pain Lymphadenopathy Hepatomegaly Splenomegaly Treatment: Repeated chemotherapy Intensive blood transfusions Bone marrow transplants

15 BLEEDING DISORDERS To prevent bleeding and bruising your body needs: Adequate amounts of normal platelets All clotting factors in sufficient quantities Strong capillary walls

16 BLEEDING DISORDERS Deficiency of platelets: This is called thrombocytopenia May be due to: Decreased production of platelets - occurs in leukaemia, radiation therapy and chemotherapy Some drugs may cause thrombocytopenia, e.g. quinine

17 BLEEDING DISORDERS Defective platelets: Can occur when, e.g. aspirin interferes with the function of the platelets A single dose of aspirin can have an effect that lasts for 7 to 10 days

18 BLEEDING DISORDERS Coagulation factors: Liver makes coagulation factors Vitamin K is necessary to activate some of these factors Deficiency of coagulation factors: Could be due to: Liver disease/damage Vitamin K deficiency Haemophilia

19 VITAMIN K DEFICIENCY Vitamin K is required for the activation of certain clotting factors Deficiency can occur in neonate/later in life Sources of vitamin K: Green leafy vegetables, produced by bowel bacteria Causes of vitamin K deficiency: Inadequate diet, lack of good bacteria in the intestines, malabsorption diseases, medicines (warfarin is a vitamin K antagonist) Neonates are often deficient because they are only starting to grow bowel bacteria and breast milk does not contain enough vitamin K.

20 HAEMOPHILIA A group of hereditary disorders where an insufficient amount of one of the clotting factors is produced Mainly found in males

21 VASCULAR DISORDERS A vitamin C deficiency will cause a weak vessel wall which can lead to bleeding Cushing s disease or cortisone therapy will also cause weak vessel walls

22 QUESTIONS