Iron deficiency anaemia

Question 1

Define iron deficiency anaemia.

Answer 1

A common microcytic anaemia caused by low insufficient iron in the body to support red blood cell production.

Question 2

Who is most commonly affected?

Answer 2

· Pre-menopausal women (because of periods).
· Infants and adolescents have increased risk due to growth spurts.
· Black women.

Question 3

What is the pathophysiology of iron deficiency anaemia?

Answer 3

· Iron is required for the formation of the haem in haemoglobin and myoglobin.
· Adults lose approximately 1mg (men) to 1.5mg (premenopausal women) a day.
· The haem from destroyed RBC’s is recycled back into new RBCs.
· Iron is absorbed mostly in the jejunum.
· It’s then transported by transferrin, and stored in either ferritin or haemosiderin forms.
· If more iron is lost or needed than can be absorbed, iron stores are used up and the patient becomes deficient.
· Poor iron stores result in impaired haemoglobin synthesis and a hypochromic, microcytic anaemia.
· Anaemia then results in decreased oxygen-carrying capacity and the resultant symptoms.

Question 4

What is the aetiology of iron deficiency anaemia?

Answer 4

· Occurs when iron absorption from the diet is not sufficient to cover iron losses.
· Causes include:

1. Long history or poor iron intake:
   · Inadequate diet, gastric surgery.
   · Malabsoprtion: coeliac disease etc.
2. Excessive iron loss - chronic blood loss:
   · GI bleeding, diverticulosis, neoplasm, UC etc.
3. Increased physiological demand for iron without increased intake - pregnancy, menses, growth spurts.

Question 5

List the most common risk factors.

Answer 5

· Black women. 
· Pregnancy. 
· Vegan diet. 
· Menorrhagia. 
· Haemodialysis. 
· Coeliac disease. 
· Gastrectomy. 
· NSAID use.

Question 6

What are the typical signs and symptoms of iron deficiency anaemia?

Answer 6

· Fatigue, dyspnoea and palpitations = common
· Pica - abnormal craving for non-food items such as dirt, ice, paint or clay.
· Nail changes - koilonychia and spooning.
· Hair loss.
· Impaired muscular performance.
· Glossitis and angular stomatitis.
· Pallor.

Question 7

What investigations would you request if you suspected a patient had iron deficiency anaemia?

Answer 7

· Blood test:

• Haemoglobin and haematocrit.
• Platelet count.
• MCV - <80 (microcytic)
• MCH <27.5 (hypochronic)

· Blood smear - microcytic, hypochromic pencil RBCs.
· Reticulocyte count (young RBCs) - low.
· Serum iron - decreased.
· Serum ferritin - decreased:
· Endoscopy.

Question 8

Differentials?

Answer 8

· Anaemia of chronic disease.
· Disorders of globin synthesis - thalassaemia’s.
· Lead intoxication.

Question 9

What are the treatment options for iron deficiency anaemia?

Answer 9

· 1st line - Oral iron replacement.
· Adjunct - Ascorbic acid - enhances iron absorption.
· 2nd line - Parenteral iron replacement.
· If symptomatic at rest with dyspnoea, chest pain or presyncope - RBC transfusion.

Question 10

What complications can arise?

Answer 10

· Cognitive impairment.
· Impaired muscular performance.
· Preterm delivery.
· High-output cardiac failure.
· Transfusion-transmitted infectious diseases.
· Developmental delay if occurs in childhood.