76  Anemia

76.1 Introduction

Anaemia is one of the most common haematological disorders in children worldwide, particularly in low- and middle-income countries. It is a major public health problem that contributes to growth retardation, impaired cognitive development, increased susceptibility to infection, and elevated morbidity and mortality. In Ghana and much of sub-Saharan Africa, anaemia frequently results from nutritional deficiencies, infections (such as malaria and helminthiasis), and genetic haemoglobin disorders.

76.2 Definition

Anaemia is defined as a reduction in the concentration of haemoglobin (Hb) in the blood below the normal range for age, sex, and altitude, resulting in decreased oxygen-carrying capacity.

76.2.1 WHO Haemoglobin Cut-offs for Anaemia in Children

Age group	Hb (g/dL) threshold
6–59 months	< 11.0
5–11 years	< 11.5
12–14 years	< 12.0
≥15 years (females)	< 12.0
≥15 years (males)	< 13.0

76.2.2 Classification by Severity (6 months–5 years)

Severity	Hb (g/dL)
Mild	10–10.9
Moderate	7–9.9
Severe	< 7

76.3 Classification

Anaemia can be classified in several ways:

76.3.1 1. Based on Pathophysiology

• Decreased production of red blood cells (e.g., iron deficiency, aplastic anaemia, bone marrow suppression).
• Increased destruction of red blood cells (haemolysis) (e.g., sickle cell disease, G6PD deficiency, malaria).
• Blood loss (acute or chronic haemorrhage, intestinal parasites).

76.4 2. Based on Red Cell Indices (Morphological Classification)

Type	MCV (fL)	Common Causes
Microcytic hypochromic	< 80	Iron deficiency, thalassaemia, anaemia of chronic disease
Normocytic normochromic	80–100	Acute blood loss, haemolysis, chronic disease
Macrocytic	> 100	Folate or vitamin B12 deficiency, hypothyroidism

77 Epidemiology

• Global prevalence: About 40% of children under 5 years are anaemic (WHO 2023).
• Sub-Saharan Africa: Up to 60% prevalence in under-fives.
• Ghana: Nationally, ~45% of children under five are anaemic (GDHS 2022).

Anaemia contributes to impaired learning ability, stunted growth, and increased risk of death from infectious diseases.

77.1 Aetiology

Anaemia in children is multifactorial and may be grouped under three broad mechanisms:

77.1.1 1. Decreased RBC Production

• Iron deficiency anaemia (IDA): Most common cause globally.
• Folate or vitamin B12 deficiency: Due to poor intake or malabsorption.
• Chronic disease: Reduced erythropoietin response and iron sequestration.
• Bone marrow suppression: Viral infections (parvovirus B19), drugs, or malignancy.

77.1.2 2. Increased RBC Destruction (Haemolysis)

• Inherited haemoglobinopathies: Sickle cell disease, thalassaemia.
• Red cell enzyme defects: G6PD deficiency.
• Immune-mediated haemolysis: Autoimmune haemolytic anaemia.
• Infections: Malaria, sepsis.

77.1.3 3. Blood Loss

• Parasitic infestations: Hookworm, schistosomiasis.
• Gastrointestinal bleeding: Meckel’s diverticulum, ulcers.
• Trauma or surgery.

77.2 Pathophysiology

Haemoglobin synthesis requires: - Iron — essential component of haem. - Globin chains — produced by bone marrow. - Vitamin B12 and folate — necessary for DNA synthesis.

Deficiency of any of these components leads to impaired erythropoiesis and reduced Hb concentration.

In anaemia, tissue hypoxia develops, stimulating increased cardiac output and erythropoietin release. Chronic anaemia leads to compensatory mechanisms such as: - Increased 2,3-DPG in RBCs (enhances oxygen delivery). - Reticulocytosis in haemolytic anaemias.

77.3 Clinical Features

77.3.1 General Symptoms

• Fatigue and weakness.
• Pallor (conjunctival, palmar, mucosal).
• Dizziness, headache.
• Tachycardia, dyspnoea on exertion.
• Poor concentration and irritability.

77.3.2 Signs

• Pallor (best seen in conjunctiva, tongue, palms).
• Systolic flow murmur.
• Bounding pulse.
• Signs of cardiac failure in severe cases.

77.3.3 Specific Features Based on Cause

Cause	Additional Features
Iron deficiency	Koilonychia, angular stomatitis, pica
Folate/B12 deficiency	Glossitis, hyperpigmentation, neurological deficits (B12)
Haemolytic anaemia	Jaundice, splenomegaly, dark urine
Sickle cell disease	Painful crises, leg ulcers, hepatosplenomegaly
Malaria	Fever, splenomegaly, hepatomegaly

77.4 Evaluation of a Child with Anaemia

77.4.1 1. History

• Dietary intake (iron-rich foods, cow’s milk overuse).
• Chronic illnesses or infections.
• Drug history (antimalarials, sulpha drugs).
• Family history of haemoglobinopathies.
• Stool characteristics (for parasitic or GI blood loss).

77.4.2 2. Physical Examination

• Pallor and jaundice.
• Growth assessment.
• Splenomegaly or hepatomegaly.
• Lymphadenopathy.
• Cardiac signs (murmurs, gallop rhythm).

77.4.3 3. Laboratory Investigations

Test	Purpose
Full blood count (FBC)	Hb, RBC indices (MCV, MCH, MCHC)
Peripheral blood film	Morphology and clues to cause
Reticulocyte count	Distinguishes decreased production vs. haemolysis
Serum ferritin, iron, TIBC	Assess iron status
Serum folate, vitamin B12	For macrocytic anaemia
Malaria test (RDT or smear)	Detect malaria parasitaemia
Stool examination	Detect ova, parasites, occult blood
Haemoglobin electrophoresis	Diagnose sickle cell or thalassaemia
Direct antiglobulin test (Coombs)	Immune haemolysis

77.5 Iron Deficiency Anaemia (IDA)

77.5.1 Epidemiology

IDA accounts for more than half of anaemia cases in African children.

77.5.2 Aetiology

• Low dietary intake (mainly cereal-based diets, little meat).
• Poor absorption (intestinal infections, celiac disease).
• Chronic blood loss (hookworm, schistosomiasis, menstruation in adolescents).
• Increased requirements (rapid growth, infection recovery).

77.5.3 Pathophysiology

Iron depletion progresses through three stages: 1. Iron depletion: Reduced ferritin stores. 2. Iron-deficient erythropoiesis: Low transferrin saturation. 3. Iron deficiency anaemia: Low Hb and microcytosis.

77.5.4 Clinical Features

• Pallor, fatigue, irritability.
• Koilonychia (spoon nails).
• Pica (craving for non-food substances).
• Glossitis and angular cheilitis.

77.5.5 Laboratory Findings

• Low Hb, MCV, MCH.
• Low serum ferritin and iron.
• High total iron-binding capacity (TIBC).
• Hypochromic microcytic RBCs.

77.5.6 Management

1. Treat underlying cause (e.g., worms, dietary deficiency).
2. Iron supplementation:
   • Elemental iron 3–6 mg/kg/day orally for 3 months after Hb normalization.
   • Ferrous sulphate preferred; give with vitamin C-rich juice.
3. Dietary advice: Encourage iron-rich foods (meat, beans, green leafy vegetables).
4. Prevent reinfection: Deworming, malaria prevention.

78 Haemolytic Anaemias

78.1 Sickle Cell Disease (SCD)

• Pathophysiology: Substitution of valine for glutamic acid at the 6th position of the β-globin chain causes HbS polymerization when deoxygenated.
• Complications: Vaso-occlusive crises, anaemia, infections, stroke.
• Management:
  • Folic acid 5 mg/day.
  • Penicillin prophylaxis (until age 5).
  • Vaccinations (pneumococcal, Hib, meningococcal).
  • Hydroxyurea to reduce crises.
  • Transfusion for severe anaemia or stroke.

78.1.1 G6PD Deficiency

• Mechanism: Lack of G6PD enzyme → inability to handle oxidative stress → RBC lysis.
• Triggers: Certain drugs (sulpha, antimalarials), fava beans, infections.
• Features: Jaundice, pallor, dark urine.
• Management: Avoid triggers, treat infections, supportive transfusion if severe.

78.2 Anaemia due to Infections

78.2.1 Malaria

• Common cause of acute severe anaemia in endemic regions.
• Mechanisms: RBC destruction, bone marrow suppression, splenic sequestration.
• Management:
  • Artemisinin-based combination therapy.
  • Blood transfusion for Hb <5 g/dL or symptomatic severe anaemia.

78.2.2 Hookworm and Schistosomiasis

• Chronic intestinal blood loss.
• Prevention: Periodic deworming, sanitation improvement.

78.3 Megaloblastic Anaemia

78.3.1 Causes

• Folate or vitamin B12 deficiency.

78.3.2 Features

• Pallor, glossitis, hyperpigmentation.
• Neurological signs (B12 deficiency only).

78.3.3 Laboratory Findings

• Macrocytosis (high MCV), hypersegmented neutrophils.

78.3.4 Management

• Oral folic acid 1–5 mg/day.
• Vitamin B12 1000 µg IM weekly × 6, then monthly if deficient.

78.4 Aplastic Anaemia

78.4.1 Definition

Bone marrow failure leading to pancytopenia.

78.4.2 Causes

• Idiopathic, viral (hepatitis, EBV, parvovirus), drugs (chloramphenicol), radiation.

78.4.3 Features

• Pallor, bleeding (petechiae), infections.

78.4.4 Management

• Stop offending agent, supportive transfusion, bone marrow transplant if severe.

78.5 Severe Anaemia — Emergency Management

78.5.0.1 Indications for Blood Transfusion

• Hb < 4 g/dL regardless of symptoms.
• Hb < 6 g/dL with respiratory distress, heart failure, or shock.

78.5.0.2 Protocol

• Packed red cells 10 mL/kg over 3–4 hours (max 15 mL/kg).
• Furosemide 1 mg/kg IV if signs of overload.

78.6 Prevention of Anaemia

1. Exclusive breastfeeding for 6 months.
2. Complementary feeding with iron-rich foods.
3. Routine deworming every 6 months after 1 year.
4. Malaria control: ITNs, chemoprevention.
5. Iron and folate supplementation in high-risk groups.
6. Control of haemoglobinopathies: Premarital screening, genetic counselling.

78.7 Public Health Approaches

• Integrated Management of Childhood Illness (IMCI): includes anaemia screening and management.
• School health programs: periodic deworming and iron supplementation.
• Maternal health interventions: prevent maternal anaemia.
• Nutrition education: balanced diet promotion.

78.8 Prognosis

• Depends on cause and severity.
• Nutritional anaemias respond well to treatment.
• Haemolytic anaemias and marrow failure syndromes require specialized care.
• Chronic anaemia impairs growth and learning outcomes.

78.9 Key Takeaways

• Anaemia in children is common, preventable, and treatable.
• Iron deficiency and malaria are leading causes in sub-Saharan Africa.
• Classification and morphological assessment guide diagnosis.
• Management requires identifying underlying causes and addressing nutrition and infections.
• Prevention strategies are essential at individual and public health levels.

78.10 Suggested References

1. World Health Organization. Haemoglobin concentrations for the diagnosis of anaemia and assessment of severity. WHO/NMH/NHD/MNM/11.1, 2023.
2. Ghana Health Service. Child Health Record Book and Treatment Guidelines, 2022.
3. Osungbade KO, Oladunjoye AO. Preventive treatments of iron deficiency anaemia in children in developing countries: What works? Afr Health Sci. 2021;21(3):1120–1130.
4. Ministry of Health, Ghana. Standard Treatment Guidelines, 2022.
5. Kassebaum NJ et al. The global burden of anaemia. Lancet Haematol. 2020;7(9):e690–e701.