[Clinical usefulness of newly developed urine protein dipstick (URINE-TP)]

We assessed the clinical usefulness of a newly developed urine protein dipstick (URINE-TP; U-TP) which can detect gamma-globulin and other proteins as well as albumin. Semiquantitative values of urine protein evaluated with U-TP were compared with those evaluated with ordinary urine protein dipsticks (BM-TEST) in 966 urine samples. The two tests showed the same semiquantitative values in 572 of 966 samples (59.2%; Group A). However, U-TP showed a more positive reaction two gradations higher in 89 samples (9.2%; Group B), and showed a more positive value with one gradation higher in 283 samples (29.3%; Group C) compared with BM-TEST. We then measured total protein, alpha 1-microglobulin (alpha 1-M), NAG and beta 2-microglobulin (beta 2-M) in urine, and serum beta 2-M, urea nitrogen (UN) and creatinine (CRE) in both Group A and Group B. In BM-TEST negative patients, urinary total protein, tubular proteins (alpha 1-M, beta 2-M) and NAG were significantly higher (p < 0.01) in Group B than in Group A. Moreover, among patients who had trace or positive results by BM-TEST, serum UN was significantly higher (p < 0.01) in Group B than in Group A. These results suggest that U-TP, a newly developed urine protein dipstick, can detect tubular proteins which cannot be detected by ordinary dipsticks. U-TP may be useful for early detection of renal tubular damage, especially when use is the combined with conventional dipsticks.