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Updated: May 17, 2026
13:13
Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Reference values for methemoglobin concentrations in children.
Kely Francini Rechetzki1, Railson Henneberg, Paulo Henrique da Silva
1Pharmaceutical Sciences, Universidade Federal do Paraná - UFPR, Curitiba, PR, Brazil.
Revista Brasileira De Hematologia E Hemoterapia
|October 11, 2012
Summary
Children aged 6-10 have higher methemoglobin levels (3.61-6.44%) than adults. These elevated methemoglobin concentrations highlight the need for pediatric-specific reference ranges.
Area of Science:
- Pediatric Hematology
- Clinical Chemistry
Background:
- Methemoglobinemia is a condition where hemoglobin is oxidized, reducing oxygen transport.
- Establishing accurate reference ranges is crucial for diagnosing methemoglobinemia in pediatric populations.
Purpose of the Study:
- To determine reference values for methemoglobin levels in children aged 6 to 10 years.
- To provide a basis for interpreting methemoglobin measurements in pediatric patients.
Main Methods:
- Studied methemoglobin concentrations in clinically healthy children.
- Utilized a laboratory-feasible method for methemoglobin measurement, avoiding toxic chemicals and expensive enzymes.
Main Results:
- Reference values for methemoglobin in children (3.61% to 6.44%) were found to be higher than in adults (1.9% to 3.8%).
Conclusions:
- Higher methemoglobin concentrations in children may be due to lower levels of cytochrome b5 and reduced cytochrome b5 reductase activity.
- Pediatric reference values are necessary, as adult ranges are inappropriate for interpreting methemoglobinemia in children.
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