Normal values for haemoglobin concentration and red cell indices in preschool children on the Highveld

Area of Science:

• Pediatrics
• Hematology
• Environmental Medicine

Background:

• Standard reference values for blood parameters are typically established at sea level.
• Children living at high altitudes may exhibit physiological differences due to chronic hypoxia.
• Accurate reference ranges are crucial for diagnosing anemia and other hematological conditions.

Purpose of the Study:

• To establish normal reference ranges for key hematological parameters in healthy children aged 1-4 years residing at high altitude (1400-1800 m).
• To compare these high-altitude ranges with established sea-level values.
• To provide updated guidelines for clinical assessment of children on the Highveld.

Main Methods:

• Collected data on haemoglobin concentration, red cell count, packed cell volume, mean cell volume, mean cell haemoglobin, and mean cell haemoglobin concentration.
• Studied a cohort of children aged 1-4 years living on the Highveld.
• Defined 'normal' based on growth attainment and adequate iron, folate, and vitamin B12 nutrition.

Main Results:

• Hematological values in children at 1400-1800 m altitude differed significantly from standard sea-level reference values.
• Mean (+/- 2 SD) ranges for parameters like haemoglobin concentration and red cell count were established for yearly age groups.
• These findings highlight the impact of altitude on pediatric hematology.

Conclusions:

• The presented mean (+/- 2 SD) ranges should be adopted as the normal reference ranges for the studied high-altitude population.
• Clinicians should consider altitude-specific reference values when evaluating the hematological status of children on the Highveld.
• Further research may explore the long-term hematological adaptations to high-altitude environments in children.