Common Causes of Anaemia and Thrombocytopenia Flashcards Preview

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Flashcards in Common Causes of Anaemia and Thrombocytopenia Deck (37):
1

3 common causes of anaemia

Iron, B12, folate deficiencies
Haemolysis
Anaemia of chronic disease

2

2 common causes of thrombocytopenia

Immune thrombocytopenic purpura (ITP)
Thrombocytic Thrombocytopenia Purpura (TTP)

3

When do you get macrocytic anaemia

Larger RBCs than normal, less Hb in the blood

4

Causes of macrocytic anaemia

B12, folate deficiencies
Metabolic abnormalities (thyroid, liver disease)
Marrow damage (alcohol, drugs, marrow disease)
Haemolysis (reticulocytes are bigger than mature RBCs)

5

MCV in macrocytic anaemia

Above normal

6

Normocytic anaemia

A normocytic anemia is defined as an anemia with a mean corpuscular volume (MCV) of 80-100 which is the normal range. However, the hematocrit and hemoglobin is decreased.

7

Causes of normocytic anaemia

Anaemia of chronic disease/inflammatory

8

3 causes of microcytic anaemia

Iron deficiency
Hb disorders
Sometimes chronic disease

9

Describe the iron balance

No excretion, limited absorption
Controlled at the level of the gut mucosa
Most iron is thus recycled
Absorbed in duodenum
Transported by transferrin
Stored in ferritin

10

Lab results of iron deficiency

Microcytic anaemia, small pale RBCs.
Low MCV
Low MCH
Low ferritin
increased hypochromic cell %

11

3 main causes of iron deficiency

Blood loss
Increased demand (pregnancy, growth)
Decreased intake (diet, malabsorption)

12

Usual iron deficiency treatment

IV iron

13

Megaloblastic anemia caused by vitamin B-12 deficiency

Pernicious anaemia

14

RBCs big and few

Megaloblastic anaemia

15

3 main causes of megaloblastic anaemia

B12 deficiency
Folate deficiency
Alcohol

16

Why does B12 or folate deficiency result in megaloblastic anaemia?

Both involved in DNA synthesis- targets rapidly dividing cells

17

Describe B12 absorption

Gastric parietal cells produce acid and intrinsic factor- binds with vit. B12 and internalised in terminal ilium. Well absorbed and stored for years.

18

3 causes of vit. B12 deficiency

Nutritional-vegans
Gastric problems (gastrectomy, pernicious anaemia)
Small bowel problems- Crohn's, TB

19

Describe the absorption of folic acid

Absorbed quite well- good diet requied. 4 month body stores.

20

3 main causes of folic acid deficiency

Diet
Malabsorption
Increased usage (pregancy, haemolysis, inflammatory disorders)

21

Autoimmune disease where you have antibodies targeted against parietal cells/intrinsic factor

Pernicious anaemia

22

An example of an effect severe B12 deficiency can have on the myelination of peripheral nerve, reversible

Subacute combined degeneration of the cord (SADC)

23

3 main causes of haemolytic anaemia

Things go wrong on the inside, membrane or outside of the RBC

24

What causes of haemolytic anaemia affect the inside of the RBC

Sickle cell
Enzyme defects (G6PD)

25

Cause of haemolytic anaemia that targets the RBC membrane

Hereditary spherocytosis

26

Cuases of haemolytic anaemia outside of the RBC

Antibodies
Drugs/toxins
Heart valves
Vasculitis (damaged endothelium)

27

Features of anaemia of chronic disease

Normal MCV
Decreased RBC production due to abnormal iron metabolism
Poor erthropoetin response

28

Describe the pathology of anaemia of chronic disease

Effects are mediated by the release of inflammatory cytokines (particularly IL-6) which affect hepcidin and results in alteration in iron absorption and release from macrophages

29

Diagnosis of anaemia of chronic disease

Normal MCV
Raised inflammatory markers
Normal/high ferritin and low serum iron

30

Causes of thrombocytopenia

Alcohol, drugs
Viral infections
ITP (Immune thrombocytopenia)
Liver disease
Coagulation disorders (DIC)

31

Low platelet disorder-diagnosis of exclusion

Immune thrombocytopenic purpura

32

How does the presentation of immune thrombocytopenic purpura vary between children and adults?

Children-self limiting, usually no treatment
Adults-chronic or relapsing/remitting

33

Small, non blanching subcutaneous haemorrhages

Petechiae

34

Treatment of immune thrombocytopenic purpura

Steroids
Splenectomy (platelets covered with antibiotics are removed in the spleen, without the spleen, no removal and platelet count rises)
Immunosuppressives
Thrombopoetin-stimulate platelet production

35

Thrombocytopenia and fever, neurological symptoms or haemolysis

Thrombotic thrombocytopenic purpura

36

Hb value for anaemia in men and women

Men-

37

In what circumstances would you get an elevated erythrocyte sedimentation rate?

Increased concentration of immuno-globulins and fibrinogen e.g. in inflammatory and neoplastic conditions