Definition of Iron deficiency anemia

Iron deficiency anaemia is a type of anaemia caused by insufficient iron in the body, leading to reduced haemoglobin production and impaired oxygen transport. Common causes include poor dietary intake, chronic blood loss, malabsorption syndromes, hookworm infestation, and increased physiological demand such as during pregnancy.

Causes

Common causes include:

• Nutritional iron deficiency

• Chronic gastrointestinal blood loss

• Heavy menstrual bleeding

• Hookworm infestation

• Malabsorption disorders

• Pregnancy and lactation

• Repeated pregnancies

• Chronic use of non-steroidal anti-inflammatory drugs (NSAIDs)

Pathophysiology

Iron is essential for haemoglobin synthesis. When iron stores become depleted, the bone marrow cannot produce adequate haemoglobin, resulting in microcytic hypochromic red blood cells. Reduced oxygen delivery to tissues causes symptoms such as fatigue, dizziness, and palpitations.

Clinical Presentation

Patients may present with:

• Fatigue and generalized weakness

• Palpitations

• Dizziness

• Shortness of breath

• Pallor

• Glossitis

• Koilonychia (spoon-shaped nails)

• Pica (craving for non-food substances such as soil or ice)

• Poor concentration

• Headache

Investigations

Important investigations include:

• Full blood picture (FBP)

• Peripheral blood smear

• Iron studies:

  • Serum iron

  • Total iron binding capacity (TIBC)

  • Serum ferritin

• Stool analysis for:

  • Hookworm ova

  • Occult blood

• Oesophagoduodenoscopy (OGD) if stool occult blood is positive to assess upper gastrointestinal bleeding

Non-Pharmacological Treatment

Prevention of Iron Deficiency

Encourage intake of iron-rich foods such as:

• Meat

• Liver

• Eggs

• Legumes (beans, peas, lentils)

• Spinach and dark green leafy vegetables

• Iron-fortified cereals and breads

• Nuts and seeds

Improving Iron absorption

• Avoid tea or coffee with meals because they reduce iron absorption

• Increase vitamin C-rich foods during meals, including:

  • Citrus fruits

  • Guavas

  • Tomatoes

  • Bell peppers

  • Broccoli

  • Cauliflower

  • Strawberries

Pharmacological Treatment

Treat the underlying cause

Management should include treatment of the underlying cause of iron deficiency anaemia.

Adult treatment

Oral Iron therapy

A: Ferrous sulfate 200 mg orally every 8 hours for 3 months.

Children

Oral Iron therapy

A: Ferrous sulphate 5 mg/kg orally every 8 hours.

• Continue treatment for 3 months after haemoglobin normalization to replenish iron stores.

Blood transfusion

B: Blood transfusion is indicated only when anaemia is life-threatening, such as:

• Cardiac failure due to anaemia

• Severe hypoxia

• Haemodynamic instability

Intravenous Iron therapy

Iron sucrose

D: Iron sucrose 200 mg diluted in 100 mL of 0.9% sodium chloride infused over 15 minutes once daily, three times weekly for 2 weeks.

Indications for parenteral Iron

Parenteral iron is indicated in patients who:

• Cannot tolerate oral iron

• Have poor response to oral iron

• Have malabsorption syndromes

• Require rapid iron replacement

Table 3.1: Number of 100mg/ampoules of iron sucrose needed for Hb increase based on the body weight

Title: Increase in Hb required (g/dL) = Target Hb − Actual Hb

Note

Formulations of iron combined with other nutritional supplements (vitamins, 0.4mg-5mg folic acid, zinc and amino acids) are recommended to enhance absorption of iron and correct combined nutritional deficiencies.

Dosage principles

• Total cumulative dose is calculated according to the haemoglobin deficit and body weight

• Use the required number of 100 mg ampoules

• Divide the cumulative dose into 200 mg doses given every 24 hours

Duration of therapy

Treatment duration may extend up to 4 weeks depending on the total cumulative iron requirement.

Monitoring

Patients should be monitored monthly using:

• Clinical assessment

• Haemoglobin levels

• Full blood count

• Reticulocyte response where available

Complications

Untreated iron deficiency anaemia may lead to:

• Heart failure

• Poor pregnancy outcomes

• Reduced physical performance

• Cognitive impairment in children

• Increased susceptibility to infections

Patient Education

Advise patients to:

• Adhere to iron therapy regularly

• Continue treatment even after symptoms improve

• Take iron tablets after meals if gastric irritation occurs

• Expect dark stools while on iron therapy

• Avoid taking iron with tea, coffee, or calcium supplements

• Seek medical review if symptoms worsen or bleeding develops

Special Populations

Pregnancy

Pregnant women are at increased risk because of increased iron requirements. Routine iron supplementation and nutritional counselling are important during antenatal care.

Children

Children with recurrent worm infestations should receive regular deworming and nutritional support.