Accurate reference intervals generated from an apparently healthy population and stratified by crucial variables such as age and gender are required to guarantee appropriate interpretation of test results. Since there were no local reference intervals in the study area, the present study aimed to establish reference intervals on serum lipid profiles and electrolytes for children and adolescents in Addis Ababa.
This community-based cross-sectional study was conducted from April to October 2019. Laboratory analysis was performed using the automatic biochemical analyzer Cobas 6000 (c501) from Roche. According to Clinical and Laboratory Standards Institute (CLSI) guidelines, reference intervals for lipid profile and electrolyte tests for apparently healthy children and adolescents were established. We used a non-parametric method to calculate the 2.5th and 97.5th percentiles with a 90% confidence interval.
In children, the reference intervals for serum potassium, sodium, chloride, calcium, magnesium, and phosphate in mmol/L were 4.37–5.20, 137–145.50, 101.90–107.90, 2.34–2.70, 0.74–0.97, and 1.42–1.85, respectively; and for total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein, the respective values were 100.76–171.70, 44.16–126.36, 60.60–105.60, and 31.60–53.70 in mg/dL, for both genders. For adolescents, the reference intervals were 4.03–5.58, 137–146, 98.90–120.90, 2.39–2.70, 0.73–0.96, and 0.96–1.80 for serum potassium, sodium, chloride, calcium, magnesium, and phosphate in mmol/L, respectively; and 97.20–189.10, 40.50–143.60, 41.70–120.90, and 21.30–57.0 in mg/dL for total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein, respectively, for both genders.
The established reference intervals in the current study revealed that both the lower and upper limits contradicted the manufacturer values as well as the available literature. The study also discovered significant gender differences in reference values for TC, TG, LDL-C, potassium, phosphate, and chloride in the adolescent age groups.