Urine dipstick for screening plasma glucose and bilirubin in low resource settings: a proof-of-concept study

The purpose of this proof-of-concept study was to investigate whether a commercially available urine dipstick may provide potentially useful information for screening plasma glucose and bilirubin in human plasma samples.

Glucose and bilirubin were assayed in 60 anonymized lithium-heparin residual plasma samples using the Roche COBAS 8000 or after pipetting 10 µL of plasma onto the pads of a commercial urine dipstick. Semiquantitative urine test results obtained with the dipstick were directly compared to paired test results obtained with COBAS.

Median plasma glucose values between COBAS and dipstick were slightly different (5.8 vs. 5.6 mmol/L; p=0.040), while no significant difference was found in bilirubin values between COBAS and dipstick (11.2 vs. 8.6 μmol/L; p=0.090). The Spearman's correlation between COBAS and dipstick was 0.83 (95% CI, 0.73-0.90; p<0.001) for plasma glucose and 0.78 (95% CI, 0.66-0.87; p<0.001) for plasma bilirubin, respectively. Cumulative agreement between COBAS and dipstick was high for both glucose (88%; kappa statistic statistics, 0.75; 95% CI, 0.58-0.92; p<0.001) and bilirubin (88%; kappa statistics, 0.76; 95% CI, 0.60-0.92; p<0.001).

The results of this proof-of-concept study indicate that the commercial urine test strip used in our study provides acceptable performance for screening plasma glucose and bilirubin levels compared with reference laboratory assays.