Spot urine protein creatinine ratio compared with dipstick proteinuria as a primary screening tool for renal disease in a community setting

Abstract Background Although, the use of manual dipstick urinalysis for proteinuria has been a common practice, the Kidney Disease Improving Global Outcomes (KDIGO) guideline on screening for chronic renal disease least advocate it use. Besides, several studies have assessed the performance of dipstick urinary in screening for proteinuria to be inaccurate, unreliable with a poor predictive values. The goal of this study was to determine and compare the presence of significant proteinuria (SP) in high-risk African children using the spot urine protein creatinine ratio (UPr/UCr) as a primary screening tool besides dipstick proteinuria screening. Methods This cross-sectional study involved 1,316 apparently healthy children recruited through a multi-stage sampling technique in Ogbomoso land, Nigeria. We performed a dipstick urinalysis on early-morning urine samples. Urinary protein content was determined using a turbidimetric method and Jaffe’s reaction to measure the urinary creatinine concentration. Statistical analysis was performed using the IBM Statistical Package for Social Sciences (SPSS)TM, Version 23.0 for Windows. Results The prevalence of SP using spot UPr/UCr (≥ 0.2) and dipstick proteinuria screening (≥1+) were 18% and 0.8%, respectively (p<0.001). Of the 224 subjects determined to have SP using UPr/UCr, the females (140; 20.1%) had a higher proportion compared to males (84; 15.4% -p=0.032). Nephrotic range proteinuria was detected in nine out of 10 subjects (90%) using UPr/UCr but in only three out of ten (30%) using the urinary dipstick method. The biserial correlation coefficient (r= 0.092; p=0.001) and inter-rater-agreement (Cohen’s Kappa = 0.01) were poor, and the McNemar’s test result was (p<0.001). Conclusion The UPr/UCr ratio technique appeared to perform better than dipstick urinalysis as a primary screening tool for renal disease. Hence, it may be adopted for early detection of SP as a kidney disease marker especially among the high risk population.