Enzyme immunoassay for urinary albumin at low concentration in diabetes mellitus

Microalbuminuria, an increased excretion of urinary albumin undetectable by Albustix test strips, appears to predict the late development of diabetic nephropathy at a stage that albuminuria might be reduced by good metabolic control Once albuminuria is detected by Albustix, it indicates the likelihood of diabetic nephropathy. Microalbuminuria is also related to an increased prevalence of proliferative retinopathy, blindness, and peripheral neuropathy. It is therefore important to detect microalbuminuria by a sensitive, rapid and simple method. Microalbuminuria can be measured by radial immunodiffusion, immunoelectrophoresis, radioimmunoassay, enzyme immunoassay, latex-bead immunoagglutination, turbidimetric immunoassay and dye-binding. The disadvantages of radioimmunoassays are: short shelf life, isotope-related health and safety hazards, and the expense of equipment used to measure gamma-emitting isotopes. Our aim in this study was to develop a simple, rapid and sensitive one-step sandwich enzyme immunoassay using anti-human albumin monoclonal antibodies for screening microalbuminuria.