Pediatric reference intervals determined in ambulatory and hospitalized children and juveniles

Area of Science:

• Clinical Chemistry
• Pediatric Laboratory Medicine
• Biomarker Analysis

Background:

• Accurate laboratory reference intervals are essential for diagnosing and monitoring pediatric health conditions.
• Established reference ranges for many laboratory methods, particularly newer ones, require periodic validation in pediatric populations.
• Age and gender are known factors influencing many biochemical markers in children.

Purpose of the Study:

• To determine pediatric reference intervals for nine widely used laboratory methods.
• To establish age- and gender-specific reference ranges for clinical use in children and juveniles.
• To compare newly derived reference intervals with previously reported values, especially for novel biomarkers.

Main Methods:

• Analysis of over 800 pediatric patients (1 day to 17 years) with diverse clinical statuses.
• Selection of a reference group with balanced gender and age distribution across five age classes.
• Utilized enzyme methods (ALT, AST, LDH, GGT, ALP) and biomarkers (sTfR, ferritin) standardized to IFCC guidelines where applicable.

Main Results:

• Confirmed typical age-related concentration patterns for most measured analytes.
• Identified distinct differences in reference limits for soluble transferrin receptor (sTfR) and ferritin compared to prior studies.
• Statistical analysis revealed significant gender-specific differences for certain laboratory parameters.

Conclusions:

• Proposed reference intervals based on the central 95th percentile values.
• The findings provide updated, clinically relevant reference ranges for pediatric laboratory testing.
• Highlights the need for method-specific and age-stratified reference intervals in pediatrics.