Lecture 3: Anaemia

Question 1

Define anaemia

Answer 1

Hb concentration falls below defined level

Question 2

What are the normal ranges of Hb?

Answer 2

Children and pregnant women: 110-160
Women: 115-165
Men: 130-180

Question 3

Signs and symptoms of anaemia

Answer 3

Symptoms:

• Lethargy
• SOB
• Palpitations
• Headache
• Often non-specific
• Worse if acute onset

Signs:

• Pallor, pale conductive
• Tachypnoea
• Tachycardia

Question 4

5 broad causes of anaemia

Answer 4

• Bleeding
• Deficiency in necessary components (iron, B12, folate)
• Haemolytic (increased destruction, shortened lifespan)
• Bone marrow dysfunction/infiltration
• Poor O2 utilisation

Question 5

Causes of iron deficiency

Answer 5

Bleeding
Nutrition deficiency
Increased requirements

Confirm with iron studies

Question 6

What are the diagnostic tests for iron?

Answer 6

Serum ferritin - storage form of iron - low if iron deficient

Serum iron - labile so reflects recent intake of iron

Serum transferrin - carrier molecule of iron - homeostatic ally goes up if iron deficient

% transferrin saturation - sensitive measure of iron status - low if iron deficient

Question 7

What causes microcytic anaemia?

Answer 7

Iron deficiency

Beta-thalassaemia

Question 8

What causes macrocytic anaemia?

Answer 8

B12 and folate deficiency

Myelodysplasia

Question 9

What causes normocytic anaemia?

Answer 9

Anaemia of chronic disease

Acute haemorrhage

Renal failure

Question 10

What are the blood film features of iron deficient anaemia?

Answer 10

Hypochromia

Microcytosis

Pencil cells

Target cells

Question 11

What are the causes of B12 deficiency?

Answer 11

Dietary - strict vegans, supplement with B12

Pernicious anaemia - autoimmune deficiency of intrinsic factor - cannot absorb B12

Malabsorption - post gastric surgery or crohn’s disease

Question 12

What are the causes of folate deficiency?

Answer 12

Dietary - common

Malabsorption - Coeliac or Crohn’s

Excess utilisation - chronic haemolysis or pregnancy

Alcohol

Drugs - methotrexate

Question 13

What are the causes of anaemia of chronic disease?

Answer 13

Inflammation

Infection

Autoimmune conditions e.g. rheumatoid arthritis

Cancer

Renal failure

Question 14

What is sickle cell anaemia?

Answer 14

Point mutation in beta globin gene causing HbS (autosomal recessive)

Increased RBC turnover = approx 20 days

Raised retics >10%

Crisis - triggered by low O2, vasoocclusive, ischaemia, pain, necrosis and organ damage

Management - analgesics, hydration and transfusion

Question 15

What happens to RBCs in sickle cell anaemia?

Answer 15

Form long filamentous strands

Insoluble at low O2 tension

RBCs become inflexible and spiky –> crisis

Question 16

What is thalassaemia?

Answer 16

Insufficient production of normal Hb (imbalance of alpha or beta chains)

Inherited autosomal recessive

Enlarged spleen, liver and heart - bones may be misshapen

Question 17

What is does the blood film for beta thalassaemia look like?

Answer 17

Microcytic and hypochromic

Question 18

Give 3 examples of bone marrow infiltration

Answer 18

Leukaemia (non-specific symptoms, bone marrow failure)

Lymphoma (lymphadenopathy, weight loss)

Myeloma (anaemia, hypercalcaemia, renal failure)

Question 19

Where are bone marrow samples obtained from?

Answer 19

Iliac crest

Question 20

What is the management of anaemia?

Answer 20

Acute - use symptoms as a guide as to whether or not to transfuse

Chronic - treat underlying cause (iron supplementation, folic acid or B12)

EPO injections

Long term transfusion