[Quantification of urinary hemoglobin by an immunological method]

The quantification method of urinary hemoglobin has not been established. We examined whether a reagent (Eiken, Tokyo) used to immunologically assay fecal hemoglobin could be utilized to quantify urinary hemoglobin. The coefficients of variation were 2.2-3.0% in the reproducibility of one-run assays using urine and 4.3-5.7% in that of multiple-run assays using the standard sample of hemoglobin. Urinary hemoglobin was unstable and decreased in a time- and temperature-dependent manner. However, addition of the hemoglobin stabilization buffer (50 mM phosphate buffer, pH 6.4) (Eiken) to urine made urinary hemoglobin stable. Urinary hemoglobin levels did not change significantly when stored at 4 degrees C for 7 days or at -80 degrees C for 30 days. The hemoglobin concentration (mean +/- SD) of urine showing 1+, 2+ and 3+ with a test strip was 385 +/- 165(n = 30), 1070 +/- 499(n = 40) and 4130 +/- 2770 ng/ml (n = 20), respectively. Urinary hemoglobin did not correlate with urinary albumin, transferrin, immunoglobulin G, N-acetyl-beta-D-glucosaminidase nor alpha 1 microglobulin. These results suggest that this immunological method using the hemoglobin stabilization buffer can be utilized for quantification of urinary hemoglobin, which may provide clinically important information.