What is the iron deficiency cut off in children?

Iron Deficiency Cut-Off Values in Children

The diagnostic cut-off for iron deficiency in children is a serum ferritin concentration of less than or equal to 15 μg/L, which confirms iron deficiency even in the absence of anemia. 1

Age-Specific Hemoglobin Cut-offs for Anemia

Iron deficiency exists on a spectrum from iron depletion (reduced iron stores) to iron-deficient erythropoiesis (depleted stores and reduced transport iron) to iron-deficiency anemia (the most severe form). While ferritin is the primary marker for iron stores, hemoglobin values are used to diagnose anemia, with age-specific cut-offs:

• Children 6-23 months: < 11.0 g/dL
• Children 24-59 months: < 11.0 g/dL
• Children 5-11 years: < 11.5 g/dL
• Children 12-14 years: < 12.0 g/dL

Diagnostic Approach to Iron Deficiency

Initial Screening

• Hemoglobin/hematocrit: First-line screening test for anemia
• Serum ferritin: Most specific test for iron stores (≤15 μg/L confirms iron deficiency) 1

Additional Tests for Confirmation

• Mean Corpuscular Volume (MCV): Decreased in iron deficiency
• Red cell Distribution Width (RDW): Increased in iron deficiency
• Transferrin saturation: Reduced (<20%) in iron deficiency
• Reticulocyte hemoglobin content (CHr): Values <26 pg strongly predict iron deficiency 2

High-Risk Populations Requiring Screening

The CDC guidelines identify specific groups of children who should be screened for iron deficiency:

• Universal screening for high-risk populations:

  • Children from low-income families
  • Children in WIC programs
  • Migrant children
  • Recently arrived refugee children
  • Screen these children between 9-12 months, 6 months later, and annually from ages 2-5 years 1

• Selective screening for:

  • Preterm or low-birthweight infants
  • Infants fed non-iron-fortified formula >2 months
  • Infants introduced to cow's milk before 12 months
  • Breastfed infants with inadequate iron from complementary foods after 6 months
  • Children consuming >24 oz of cow's milk daily
  • Children with special healthcare needs 1

Clinical Significance of Iron Deficiency

Iron deficiency in children, even without anemia, can cause:

• Developmental delays and behavioral disturbances
• Decreased motor activity and social interaction
• Reduced attention to tasks
• Impaired cognitive function that may persist beyond school age if not fully corrected 1

Treatment Protocol

When iron deficiency is identified:

1. Confirm diagnosis with repeat hemoglobin/hematocrit if screening is positive
2. Initiate treatment with 3 mg/kg/day of iron drops between meals
3. Recheck hemoglobin in 4 weeks - an increase of ≥1 g/dL confirms iron deficiency anemia
4. Continue treatment for 2 additional months if confirmed
5. Follow up approximately 6 months after successful treatment 1

Common Pitfalls in Diagnosis

• Relying solely on hemoglobin: Iron deficiency can exist without anemia
• Misinterpreting ferritin: As an acute phase reactant, ferritin may be falsely elevated during infection or inflammation
• Overlooking dietary factors: Excessive cow's milk intake (>24 oz daily) is strongly associated with iron deficiency 3
• Inadequate follow-up: Failure to confirm response to iron therapy may miss other causes of anemia

Early identification and treatment of iron deficiency is critical to prevent long-term neurodevelopmental consequences, as developmental delays may persist even after correction of the iron deficiency 4.