Anaemia

Question 1

What is the definition of anaemia? and what are the cut offs for men and women?

Answer 1

Low Hb concentration and may be due to:

• low red cell mass
• or, increased plasma volume

Men: <13.5g/dl

Women: <11.5g/dl

Question 2

What are the symptoms of anaemia?

Answer 2

Asymptomatic if slow onset - patient able to compensate

Generalised:

Fatigue, dyspnoea, headache/faintness, papitations, tinnitus, anorexia, angina

Question 3

What are the general signs of anaemia?

Answer 3

May be absent

Pallor, hyperdynamic circulatory signs - tachycardia, ejection systolic murmur, cardiac enlargement → heart failure and peripheral oedema

Question 4

What is Microcytic anaemia? and what are the causes?

Answer 4

Low Mean Cell Volume (≤ 27pg)

Iron deficiency anaemia

Thalassaemia - abnormal Hb formation

Sideroblastic anaemia

Question 5

What is normocytic anaemia and what are the causes?

Answer 5

Normal MCV

Acute blood loss

Anaemia of chronic disease (can ↓MCV)

BM failure - ↓WCC or ↓Plateletes

Renal failure, Hypothyroidism (can ↑MCV)

Haemolysis (can ↑MCV)

Pregnancy

Question 6

What is a combination of normocytic anaemia with ↓WCC and ↓plateletes likely to be?

Answer 6

Bone Marrow Failure

Question 7

What is macrocytic anaemia?

Answer 7

High MCV

Vitamin B12/Folate deficiency

Alcohol excess/liver disease

Reticulocytosis, cytotoxics (hydroxycarbamide), myelodysplastic syndromes, marrow infiltration, hypothyroidism, antifolate drugs - Phenytoin

Question 8

What is haemolytic anaemia and what would lead to its suspicion?

Answer 8

Normocytic/Macrocytic

Reticulocytosis,

Mild macrocytosis

↓Haptoglobin

↑Bilirubin and ↑Urobilinogen

Mild Jaundice

Question 9

What factors can cause decreased marrow production?

Answer 9

Stem cell defects/dysfunction

Hypoproliferation

Marrow infiltration

Nutritional deficiencies

Question 10

What are the intrinsic and extrinsic causes of stem cell dysfunction?

Answer 10

Intrinsic - Stem cell aplasia, stem cell abnormalities (e.g. Leukaemia)

Extrinsic - Drugs, viruses, chemicals, radiation - kill/impair stem cell function

Question 11

What are the causes of hypoproliferation which cause anaemia?

Answer 11

Hypostimulation - renal insufficiency → low EPO; endocrinopathies

Extrinsic inhibition of proliferation - Cytokine inhibition (anaemia of chronic disease), Viral infections, Autoimmune reactions

Question 12

What causes marrow infiltration?

Answer 12

Functional marrow space reduced by cancers (metastasis, lymphomas, myelomas, or leukaemias), or fibrosis

Question 13

What nutritional deficiencies can cause anaemia?

Answer 13

Iron

Folate and B12

Protein malabsorption

Question 14

What are the intrinsic factors which cause Haemolysis?

Answer 14

Abnormal Hb

HbS (Sickle) polymerises → Damage to RBCs

β-Thalassaemia causes excess α-globin chain precipitation, binding and damage to cell membranes

Membrane protein defects

• Hereditary spherocytoses/elliptocytoses cause abnormally shaped cells → less compressible and more readily lysed in spleen etc.

Question 15

What extrinsic factors may lead to haemolysis?

Answer 15

Autoimmune reactions - destroy RBCs. (Alloimune - destory transfused RBCs)

Hypersplenism - ↑RBC lysis rates

Microangiopathic disorders - TTP, DIC

Infections - Malaria, Clostridia may lyse RBCs

Question 16

What are the causes of iron deficiency anaemia?

Answer 16

Blood loss - menorrhagia

Poor diet - babies or children, specific diet/poverty

Malabsorption - Coeliac’s

GI blood loss - parasites such as hookworm

Question 17

What are the signs of iron deficiency anaemia?

Answer 17

Koilonychia

Atrophic Glossitis

Angular Cheilitis

Question 18

What investigations should be done for iron deficiency anaemia?

Answer 18

FBC

• Microcytic, hypochromic anaemia
• Ferritin decreased (but increased in inflammation)
• Decreased serum iron
• Increased Total Iron Binding Capacity

Question 19

What is the treatment for Iron deficiency anaemia?

Answer 19

Treat the cause

Oral iron e.g. Ferrous Sulphate 200mg/8h

S/E: Nausea, abdominal discomfort, diarrhoea/constipation, black stools

Question 20

What is anaemia of chronic disease?

Answer 20

Associated with many diseases, including chronic infection, vasculitis, RA, malignancy, RF

• Cytokine driven inhibtion of RBC production

Question 21

What would the FBC show for anaemia of chronic disease?

Answer 21

Mild, normocytic anaemia

Normal/increased ferritin

Question 22

What is the treatment for anaemia of chronic disease?

Answer 22

Treat underlying disease

• Treat inflammatory condition
• Treat renal failure with EPO