What is the recommended initial evaluation and treatment approach for a pediatric patient presenting with anemia, considering their age, medical history, and severity of anemia?

Anemia in Children: Initial Evaluation and Treatment

Immediate Action for Presumptive Iron Deficiency Anemia

For children presenting with anemia who are hemodynamically stable, confirm the diagnosis with a repeat hemoglobin/hematocrit test, and if both tests agree and the child is not acutely ill, make a presumptive diagnosis of iron deficiency anemia and begin treatment immediately with oral iron supplementation at 3 mg/kg per day of elemental iron administered between meals. 1, 2, 3

Age-Specific Screening and Risk Assessment

Universal Screening Recommendations

• Screen all children before 12 months of age for anemia, as recommended by the American Academy of Pediatrics, despite the US Preventive Services Task Force noting insufficient evidence for universal screening 2, 4, 5
• Repeat screening at 24 months for high-risk children 5

Critical Risk Factors to Identify

• Excessive cow's milk intake (>24 ounces daily) - the single most common modifiable risk factor 1, 2, 3
• Limited iron-fortified foods in diet 1
• History of prematurity or low birth weight 1
• Introduction of cow's milk before 12 months of age 1
• Breastfed infants without iron supplementation after 4-6 months 2

Initial Laboratory Evaluation by Mean Corpuscular Volume (MCV)

Microcytic Anemia (Most Common - 90% of Cases)

• Iron deficiency is the presumptive diagnosis - begin treatment immediately without waiting for confirmatory tests in stable, non-acutely ill children 1, 2, 3
• Reserve serum ferritin (≤15 μg/L confirms iron deficiency) for non-responders at 4-week follow-up 2, 3
• Consider lead levels and hemoglobin electrophoresis only if patient fails to respond to iron therapy 6, 7

Normocytic Anemia

• Obtain reticulocyte count to assess bone marrow function 6, 7
• Elevated reticulocyte count suggests hemolysis or blood loss - evaluate for hemoglobinopathies, membranopathies, or acute bleeding 6, 7
• Low reticulocyte count indicates bone marrow suppression - requires immediate pediatric hematology referral 4, 6

Macrocytic Anemia (Uncommon in Children)

• Check vitamin B12 and folate levels, thyroid function tests 6, 7
• Consider bone marrow disorders if nutritional deficiencies excluded 5, 7

Treatment Protocol for Iron Deficiency Anemia

Dosing by Age and Severity

• Standard dose for all ages: 3 mg/kg per day of elemental iron (ferrous sulfate preferred) administered between meals 1, 2, 3
• Preterm/low birthweight infants: 2-4 mg/kg/day (maximum 15 mg/day) from 1 month until 12 months 2
• Breastfed term infants <12 months: 1 mg/kg/day if insufficient dietary iron 2
• Even with hemoglobin as low as 6.2 g/dL, oral iron remains first-line in hemodynamically stable children 1, 3

Critical Administration Instructions

• Administer between meals - food reduces absorption by up to 50% 2, 3
• Never give with milk or meals - this is the most common cause of treatment failure 1, 2, 3
• Add vitamin C-rich foods with iron doses to enhance absorption 1, 2, 3
• Ferrous sulfate is preferred over other iron salts because it is most cost-effective and provides known amounts of elemental iron 2

Mandatory Dietary Modifications

• Limit cow's milk to maximum 24 ounces daily - this is non-negotiable and must be addressed immediately 1, 2, 3
• Introduce iron-fortified cereals (two or more servings daily starting at 4-6 months) 2
• Add iron-rich foods appropriate for age 1, 2, 3

Monitoring and Treatment Duration

4-Week Follow-Up (Mandatory)

• Repeat hemoglobin or hematocrit at exactly 4 weeks 1, 2, 3
• Treatment response criteria: Increase of ≥1 g/dL in hemoglobin OR ≥3% in hematocrit confirms diagnosis and adequate response 1, 2, 3

Duration of Therapy

• Continue iron for 2-3 additional months after hemoglobin normalizes to replenish iron stores 1, 2, 3
• Premature discontinuation leads to rapid recurrence 3

Management of Non-Responders at 4 Weeks

If hemoglobin fails to increase by ≥1 g/dL:

• Measure serum ferritin to confirm iron deficiency 1, 3
• Obtain MCV and red cell distribution width (RDW) to evaluate for thalassemia 1, 3
• Check lead levels in high-risk populations 6
• Assess compliance with between-meal dosing and milk restriction 3
• Consider gastrointestinal blood loss if severe or refractory 6

Indications for Blood Transfusion (Rare)

Blood transfusion is reserved exclusively for hemodynamic instability - tachycardia, hypotension, or signs of heart failure 3

• Do not transfuse based on hemoglobin level alone, even with severe anemia (Hgb <7 g/dL), if the child is hemodynamically stable 1, 3

Indications for Pediatric Hematology Referral

• Failure to respond to appropriate iron therapy after 4 weeks 4
• Any evidence of bone marrow suppression (low reticulocyte count with normocytic anemia) 4, 6
• Suspected hemoglobinopathy or thalassemia 4
• Macrocytic anemia without clear nutritional cause 4

Critical Pitfalls to Avoid

• Do not administer iron with meals or milk - absorption decreases by 50% 1, 2, 3
• Do not discontinue treatment when hemoglobin normalizes - continue for 2-3 months to replenish stores 1, 2, 3
• Do not overlook dietary counseling - failure to limit milk intake leads to rapid recurrence 1, 3
• Do not transfuse stable patients - this carries unnecessary risks 1, 3
• Do not delay treatment waiting for confirmatory tests in stable children with presumptive iron deficiency 1, 2, 3

Long-Term Consequences of Untreated Anemia

Iron deficiency anemia causes irreversible neurodevelopmental delays, decreased motor activity, impaired social interaction, and reduced attention span that may persist beyond school age if not fully reversed with early treatment 1, 2, 3