Introduction of serum creatinine for detecting chronic kidney disease in pediatric lifestyle-related disease screening

Abstract

As most children with stage 3–5 chronic kidney disease (CKD) in Japan present with nonglomerular disease, its detection is difficult during annual urinalysis conducted in school. Since 2020, in Uwajma city, Japan, to screen pediatric CKD, the practice of measuring serum creatinine (Cr) levels was introduced in addition to the pediatric lifestyle-related disease checkup, which involved measuring total and HDL cholesterol levels in fourth-grade elementary school children. Decisions regarding positive screening were made according to the Cr-based estimated glomerular filtration rate (Cr-eGFR). Similar screening practice was initiated in Ozu City in 2022 for fourth graders in elementary school (E4) and first graders in junior high school (J1). Till date, 1,900 E4 and 352 J1 have been screened. The criterion for positive screening was Cr-eGFR level of <90 and 85 mL/min/1.73 m² for E4 and J1, respectively. Accordingly, 125 E4 and 19 J1 were selected for further examination, of which 85 E4 and 11 J1 visited our department. We detected five children with stage 2 or higher CKD and one child with stage 3 CKD in association with autosomal recessive polycystic kidney disease who had never shown abnormal findings upon urine analysis in the school. These findings demonstrate the potential prevalence of CKD in the general pediatric population and the clinical implication of measuring creatinine in pediatric lifestyle-related disease checkups.