Pediatric Anemia

Comprehensive guide to diagnosis and management of anemia in children

Overview Iron Deficiency Diagnosis Treatment

Anemia Overview

Definition & Epidemiology

Anemia is defined as a hemoglobin concentration below the 5th percentile for age and sex. It affects approximately 25% of children worldwide, with iron deficiency being the most common cause.

Age-Specific Hemoglobin Thresholds

  • • 6-59 months: <11.0 g/dL
  • • 5-11 years: <11.5 g/dL
  • • 12-14 years: <12.0 g/dL
  • • 15+ years: <12.0 g/dL (F), <13.0 g/dL (M)

Common Types of Pediatric Anemia

  • Iron deficiency anemia (most common)
  • Anemia of chronic disease
  • Nutritional deficiencies (B12, folate)
  • Hemolytic anemias
  • Thalassemias
  • Sickle cell disease

Clinical Presentation

Mild Anemia (Hb 9-11 g/dL)

  • • Often asymptomatic
  • • Subtle fatigue
  • • Decreased exercise tolerance

Moderate Anemia (Hb 7-9 g/dL)

  • • Fatigue and weakness
  • • Pallor (conjunctiva, nail beds)
  • • Irritability
  • • Decreased appetite

Severe Anemia (Hb <7 g/dL)

  • • Tachycardia, tachypnea
  • • Heart murmur
  • • Restless leg syndrome
  • • Pica (ice, starch, dirt)
  • • Growth retardation

Iron Deficiency Anemia

Pathophysiology

Iron deficiency anemia develops in three stages:

Stage 1: Iron Depletion

Decreased iron stores (↓ ferritin), normal Hb and MCV

Stage 2: Iron Deficient Erythropoiesis

↑ TIBC, ↓ transferrin saturation, ↑ FEP, normal Hb

Stage 3: Iron Deficiency Anemia

↓ Hemoglobin and hematocrit with microcytosis

Risk Factors

Infants & Toddlers

  • • Exclusive breastfeeding >6 months without iron supplementation
  • • Excessive cow's milk intake (>24 oz/day)
  • • Low birth weight or prematurity
  • • Early introduction of cow's milk (<12 months)

School Age & Adolescents

  • • Rapid growth spurts
  • • Menstrual losses (adolescent girls)
  • • Poor dietary iron intake
  • • Vegetarian diets without adequate planning

Pathological Causes

  • • Gastrointestinal bleeding
  • • Malabsorption disorders
  • • Chronic kidney disease
  • • Inflammatory bowel disease

Daily Iron Requirements by Age

Diagnostic Approach

Laboratory Studies

Initial Testing

  • • Complete Blood Count (CBC) with differential
  • • Reticulocyte count
  • • Peripheral blood smear
  • • Iron studies (ferritin, TIBC, transferrin saturation)

Iron Deficiency Anemia Lab Values

Parameter Finding
Hemoglobin ↓ Decreased
MCV ↓ <80 fL (microcytic)
RDW ↑ >14% (increased)
Ferritin ↓ <12 ng/mL
TIBC ↑ >450 μg/dL
Transferrin Saturation ↓ <16%

Differential Diagnosis

Microcytic Anemia (MCV <80 fL)

  • • Iron deficiency anemia
  • • Thalassemia trait
  • • Anemia of chronic disease
  • • Lead poisoning
  • • Sideroblastic anemia

Normocytic Anemia (MCV 80-100 fL)

  • • Acute blood loss
  • • Hemolytic anemia
  • • Bone marrow failure
  • • Chronic kidney disease
  • • Anemia of chronic disease

Macrocytic Anemia (MCV >100 fL)

  • • B12 deficiency
  • • Folate deficiency
  • • Hypothyroidism
  • • Liver disease
  • • Reticulocytosis

Clinical Pearl

In children with concurrent thalassemia trait and iron deficiency, the MCV may be disproportionately low relative to the degree of anemia.

Treatment & Management

Iron Supplementation

Oral Iron Therapy

Dosage: 3-6 mg/kg/day of elemental iron divided into 1-2 doses
Duration: Continue for 2-3 months after normalization of hemoglobin

Iron Preparation Options

Preparation Elemental Iron Notes
Ferrous sulfate 20% Most cost-effective
Ferrous gluconate 12% Better tolerated
Ferrous fumarate 33% Highest iron content
Polysaccharide-iron 100% Fewer GI side effects

Administration Tips

  • Give on empty stomach if tolerated (increases absorption)
  • Administer with vitamin C to enhance absorption
  • Avoid with milk, tea, coffee, or calcium supplements
  • Use dropper or syringe for liquid preparations
  • Brush teeth after liquid iron to prevent staining

Response to Treatment

Expected Response Timeline

1
3-5 days

↑ Reticulocyte count

2
1-2 weeks

↑ Hemoglobin (1-2 g/dL)

3
4-6 weeks

Normalization of Hb

4
2-3 months

Iron stores replenished

Poor Response Indicators

  • • No reticulocyte response within 1 week
  • • Hemoglobin increase <1 g/dL after 4 weeks
  • • Consider: non-compliance, malabsorption, ongoing blood loss

Side Effects & Management

Common Side Effects (20-25%)
  • • Nausea, vomiting, abdominal pain
  • • Constipation or diarrhea
  • • Dark stools (normal, reassure parents)
  • • Metallic taste
Management Strategies
  • • Start with lower dose, gradually increase
  • • Take with food if GI upset (↓ absorption)
  • • Switch to different iron preparation
  • • Consider alternate-day dosing

Prevention Strategies

Infants (0-12 months)

  • • Iron supplementation for exclusively breastfed infants >4 months
  • • Iron-fortified formula if not breastfeeding
  • • Iron-fortified cereals at 4-6 months
  • • Avoid cow's milk before 12 months

Toddlers (1-3 years)

  • • Limit cow's milk to 16-24 oz/day
  • • Iron-rich foods (meat, poultry, fish)
  • • Iron-fortified cereals and breads
  • • Vitamin C with iron-rich meals

School Age & Teens

  • • Balanced diet with iron-rich foods
  • • Screening for menstruating adolescents
  • • Supplement for vegetarians if needed
  • • Address underlying causes of blood loss