Anaemia in Children 

Lesson Objectives

By the end of this lesson, learners should be able to:

1. Define anaemia and identify age-specific normative red blood cell (RBC) values.

2. Describe the major causes of anaemia in children.

3. Recognize the clinical signs and symptoms of anaemia.

4. Outline the key investigations required to diagnose and classify anaemia.

5. Explain the treatment strategies for iron deficiency, megaloblastic, and haemolytic anaemia.

6. Understand when to escalate care or refer to higher-level facilities.

Description

Anaemia is defined as a haemoglobin (Hb) concentration or hematocrit two or more standard deviations below the mean for age and sex. Causes include decreased red cell production due to deficiencies of iron, folate, or vitamin B12; bone marrow failure; or increased red cell destruction (haemolysis).

Haemolytic anaemia may result from extra-corpuscular defects (often immune-mediated) or intra-corpuscular defects (e.g., enzyme deficiencies such as G6PD, membrane defects such as hereditary spherocytosis, or globin defects such as sickle cell disease and thalassemia).

Age-Specific Normative RBC Values

Causes of Anaemia

1. Decreased red cell production

   • Nutritional deficiencies: iron, folate, vitamin B12

   • Bone marrow failure: aplastic anaemia, malignant infiltration, congenital defects

2. Increased red cell destruction (haemolysis)

   • Extra-corpuscular defects: Immune-mediated (autoimmune hemolysis)

   • Intra-corpuscular defects:

     • Enzyme defects: G6PD deficiency, pyruvate kinase deficiency

     • Membrane defects: hereditary spherocytosis, elliptocytosis

     • Globin defects: sickle cell anemia, thalassemia

Signs and Symptoms

• Pallor

• Fatigue, palpitations, dizziness, poor concentration

• Headache

• Jaundice

• Pica

• Koilonychias (spoon-shaped nails)

• Bruising, bleeding episodes, petechiae, purpura

• Fever

• Tachycardia, edema

• Hepatosplenomegaly, lymphadenopathy

Investigations

Key Tests:

• Full blood count (FBC)

• Peripheral smear

• Reticulocyte count

• Total and direct serum bilirubin

Other Tests:

• ESR, LDH

• Coombs test (direct and indirect)

• Sickling test

• Bone marrow aspiration/biopsy

• Coagulation studies (APTT, PT/INR, D-dimers, FDPs)

• Stool for occult blood, parasites, ova

• Urinalysis (dipstick, microscopy)

Treatment

1. Treat the underlying pathology.

2. If anaemia persists without identifiable cause, refer to higher-level care.

3. Replace deficient blood products:

   • Packed RBCs (mL) = body weight × Hb deficit × 4

   • Whole blood (mL) = body weight × Hb deficit × 6

   • Max 20 mL/kg/day

Mild anaemia:

• Treat with haematinics (Hb rises ~1 g/dL per month)

• Avoid routine iron in sickle cell disease unless iron deficiency confirmed

Iron Deficiency Anaemia

• Causes: poor nutrition, chronic blood loss, malabsorption, hookworm

• Signs: fatigue, palpitations, dizziness, glossitis, pica, koilonychias

• Investigations: low Hb, MCV, MCHC, raised RDW, microcytic hypochromic red cells

• Treatment:

  • Address underlying cause

  • Life-threatening cases: blood transfusion

  • Oral ferrous sulphate 5 mg/kg PO every 8 hrs; continue for 3 months after normal Hb achieved

Megaloblastic Anaemia

• Cause: vitamin B12 or folate deficiency → large abnormal RBCs (megaloblasts)

• Signs: pallor, depression, hair loss, paraesthesia, tremors, palsies, beefy tongue, ataxic gait

• Investigations: FBC (may show pancytopenia), peripheral smear (oval macrocytes, hypersegmented neutrophils), serum B12, folate, electrolytes, LFTs, urea, creatinine, reticulocyte count, bone marrow if indicated

• Treatment:

  • Vitamin B12 deficiency without neuro signs: Hydroxycobalamine 1 mg IM 3×/week for 2 weeks, then 1 mg every 3 months

  • With neurological signs: Hydroxycobalamine 1 mg IM on alternate days until improvement, then 1 mg every 2 months

  • Always start folic acid 5 mg PO daily for ≥2 months

  • Iron supplementation: Ferrous sulphate 200 mg PO 8-hourly for ≥3 months

Haemolytic Anaemia

Signs: pallor, jaundice, splenomegaly

Investigations: FBC, reticulocyte count, bilirubin (direct/indirect), peripheral smear

Treatment:

• Supportive: treat underlying cause, blood transfusion if severe, plasmapheresis if indicated

• Pharmacological: immunosuppressants for autoimmune hemolytic anemia (prednisolone, cyclophosphamide, cyclosporin, azathioprine, IVIG), folic acid 5 mg PO daily

• Surgical: splenectomy if unresponsive to pharmacologic treatment