Anaemia

Question 1

Define anaemia

Answer 1

Haemoglobin (Hb) level two standard deviations below the mean for the age and sex of the patient

Question 2

Aetiology of microcytic anaemia

Answer 2

Defect in haem synthesis:
Iron deficiency (most common)
Anaemia of chronic disease (often normocytic)

Defect in globin synthesis (thalassaemia)
Sideroblastic anaemia
- X-linked
- Secondary to alcohol, drugs (isoniazid, chloramphenicol), lead, myelodysplasia
- Lead poisoning e.g. in scrap metal or smelting workers

Question 3

Causes of iron deficiency anaemia

Answer 3

Bleeding e.g. menstrual/GI
Increased use e.g. growth/pregnancy, malignancy
Dietary deficiency e.g. vegetarian
Malabsorption e.g. coeliac, IBD

Question 4

Aetiology of normocytic anaemia

Answer 4

Either a decreased blood volume or decreased erythropoeisis
Anaemia of chronic disease
(early IDA)
Haemolytic anaemia
Blood loss
Hypothyroidism
Renal failure
Bone marrow failure

Hypoproliferative
Haematological malignancies
Aplastic anaemia
Chronic renal failure
Hypothyroidism

Hyperproliferative
Haemolytic anaemia: MAHA, AIHA, drugs, infection, inherited conditions, transfusion reactions, burns

Question 5

Aetiology of macrocytic anaemia

Answer 5

Megaloblastic:
- vit B12 deficiency
- folate deficiency
- Drugs e.g. methotrexate, hydroxyurea, azathioprine, zidovudine

Non-megaloblastic:
Alcohol excess
Haemolysis
Liver disease
Myelodysplasia
Multiple myeloma
Hypothyroidism
Drugs e.g. imatinib

Question 6

Symptoms and signs of anaemia

Answer 6

Lethargy/fatigue
Light-headedness/dizziness
Shortness of breath
Issues concentrating
Easy bruising
Night sweats
Weight loss
Fever

Pallor
Pale conjunctivae
Tachycardia, tachypnoea

Question 7

Investigations for anaemia

Answer 7

FBC: Hb reduced, Assess MCV
- MCV <80 - microcytic
- MCV 80-100 - normocytic
- MCV > 100 - macrocytic
Iron studies:
Blood film
Vit B12/folate levels
LDH and haptoglobin
DAT or Coombs
Bilirubin
U&Es
G6PD level

> 60yo → 2WW ?colonic malignancy

Question 8

What blood results would be found in iron deficiency anaemia

Answer 8

• Serum iron ↓
• Iron binding capacity ↑
• Serum ferritin ↓
• Transferrin ↓

Question 9

What do the following suggest if found on blood film

Answer 9

Target cells: IDA, haemoglobinopathies
Eliptocytes/pencil cells: IDA, haemoglobinopathies
Spherocytes: hereditary spherocytes/autoimmune haemolysis
Fragmented red cells: haemolysis
Bite cells: G6PD deficiency
Nucleated red blood cells
Nucleated red blood cells: bone marrow infiltration/haemolysis
Sickle cells: sickle cell anaemia
Tear drop: vit B12 deficiency/bone marrow infiltration

Question 10

Management for iron deficiency anaemia

Answer 10

1. Exclude any underlying cause of anaemia e.g. GI bleeds, malignancy, thalassaemia
2. Diet and advice

First line: iron supplementation e.g. 200mg ferrous sulphate tablets 2 or 3x daily (empty stomach with a drink containing vitamin C)
Second line: parenteral iron supplements
± Oral folic acid if the cause is not known (can exacerbate B12 deficiency symptoms if given)
→ recheck FBC within 4 weeks of treatment
→ treatment should be continued for 3 months after iron deficiency is corrected to allow iron stores to be replenished

Question 11

What dietary advice should be given for iron deficiency anaemia

Answer 11

Increase iron intake - green leafy vegetables (broccoli, spinach), nuts, beans, seeds, red meat, liver, kidney, oily fish, fortified breakfast cereals
Vit C enhances absorption of iron, whereas tea and coffee inhibit iron absorption
Avoid cow’s milk, tea, and high fibre foods

Question 12

Side effects of iron supplementation

Answer 12

Diarrhoea
Constipation
Black stools
Abdominal pain
Nausea