Conclusions: Measurements of urinary albumin, total protein, and albumin-to-creatinine ratio are minimally affected by storage at ؊70°C for approximately 2.5 yr. Prolonged storage results in small decreases of urinary albumin and protein that do not substantially affect phenotype classification of overt renal disease.

We describe a new portable uric acid (UA) meter, called the UASure (Apex Biotechnology Corp., Hsinchu, Taiwan). The UASure is an electrochemical blood UA meter designed for fast monitoring of UA concentrations in one drop of capillary blood using an electrochemical test strip. We compared the UASure with the standard method, the Hitachi 7600 modular system (Hitachi, Tokyo, Japan), in 146 volunteers (average age 62.5 +/- 12.8 years). Of these, 65 were known hyperuricemic subjects, 17 of whom received medical therapy. The patients donated their capillary and venous blood samples in random order. Capillary blood and one drop of venous blood were tested immediately by the UASure. The venous blood in the test tube was sent to the central laboratory for serum UA measurement by the Hitachi 7600. The intra-assay coefficients of variation (CVs) of the UASure were 4.79%, 5.77%, and 3.08% at UA levels of 5.8, 7.1, and 13.5 mg/dl, respectively. The UA concentrations tested by the UASure correlated well with those by the Hitachi 7600 (r = 0.87 in venous sampling and r = 0.78 in capillary sampling, P < 0.001). The intraclass correlation was good for venous samples by the UASure (rI = 0.84, 95% CI 0.82-0.90), somewhat below the meaningful criterion for capillary samples by the UASure (rI = 0.77, 95% CI 0.69-0.83). UASure with venous sampling is interchangeable with the standard method for UA measurement.

No abstract