2021 Volume 70 Issue 2 Pages 308-311
Measurement of proteinuria is vital for diagnosing renal disease and determining severity. The urine dipstick test is the most widely used screening method. However, the proteinuria interpretation is affected by urine specific gravity (SG). We collected the medical records of patients (aged < 19 years) from January 2014 to December 2019 at our hospital. This study included 508 patients whose protein levels measured by the dipstick test, urinary protein-to-creatinine ratio (Up/Ucr), and SG were determined concomitantly. These patients were stratified according to their protein levels measured by the dipstick test (5 groups) and SG (4 groups). The percentages of pathological proteins determined using Up/Ucr were calculated for all 5 × 4 cells. Normal Up/Ucr ratios were defined as less than 0.5 for younger than 2 years and less than 0.2 for older than 2 years. In the group whose dipstick test was negative and SG was ≤ 1.010, 25/106 (23.6%) of the patients were considered as having pathological proteins. In children, the urine SG is often low since their kidneys are premature. Hence, the combination of dipstick test results and SG is considered to be more important for children than for adults. Adding SG to urine protein screening should decrease the underestimation of proteinuria.
