Diagnostic accuracy of single-voided urine protein/ creatinine ratio for proteinuria assessment in children with nephrotic syndrome
Abstract
Background Measurement of protein excretion is not onlyused for diagnostic purpose but also to monitor disease severity
and prognosis in children with nephrotic syndrome (NS).
The common method to measure proteinuria is 24-hour urine
collection. However, 24-hour urine collection is cumbersome,
time consuming, and tedious. An alternative simplified method
is the measurement of protein/creatinine ratio in single-voided
urine specimens.
Objective The aim of this study was to determine whether urine
protein/creatinine ratio is accurate to predict pathologic (> 100
mg/m2/day) and massive proteinuria (> 1 g/m2/day).
Methods Seventy single voided and 24-hour urine specimens
were collected from children aged 3-18 years. The relationship
between urinary protein/creatinine ratio and total daily protein
excretion was calculated using correlation and linear regression
analysis. Diagnostic test was conducted to estimate the accuracy
of protein/creatinine ratio for the diagnosis of pathologic and
massive proteinuria in NS.
Results Correlation coefficient between quantity of protein in
24-hour urine specimens and protein/creatinine ratio in singlevoided urine specimens was 0.96 (R2=0.93). Both sensitivity and specificity of urinary protein/creatinine ratio were 87% in diagnosing pathologic proteinuria, whereas the sensitivity and specificity of the ratio to predict massive proteinuria were 88% and 91%, respectively.
Conclusion The urinary protein/creatinine ratio in single voided
urine specimen has a good accuracy to predict pathologic and
massive proteinuria in children with NS aged 3-18 years.
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Accepted 2016-09-12
Published 2009-12-31