A comparison between two screening methods for detection of microproteinuria

OBJECTIVE: We compared two screening tests for microproteinuria with 24-hour quantitative measurements to determine which method is better at predicting clinically significant proteinuria. STUDY DESIGN: We obtained 690 24-hour urine collections from both low- and high-risk patients seen for prenatal care. Qualitative screening for microproteinuria on the basis of the protein-error-of-indicators principle (Ames Multistix 10SG and Micro-bumintest, Miles Diagnostic Division, Elkhart, Ind.) was done by the same investigator (C.S.). Quantitative assay was done by use of pyrogallol red-molybdate for total protein and by radioimmunoassay for albumin. RESULTS: The Micro-bumintest had a sensitivity of 87% compared with 36% for the Multistix 10SG. It also had a higher specificity and higher positive and negative predictive values. The Micro-bumintest was a better screening test in patients with significant protein excretion (>300 mg/24 hours). CONCLUSION: The Micro-bumintest has a much higher sensitivity and a lower false-negative rate than does the Multistix 10SG. Our data support the Micro-bumintest as a better screening test for clinically significant proteinuria.