Albuminuria and proteinuria in hospitalized patients as measured by quantitative and dipstick methods

Abstract

We tested patients' urines for albumin, protein, and creatinine by quantitative and dipstick methods. The concentrations of these analytes were established by quantitative, cuvet-based chemistry methods that we assumed gave the "correct" values. There was good to excellent agreement of the dipstick results with the quantitative methods for the above three analytes. We found many patients who excreted pathological amounts of albumin and/or protein who did not have a diagnosis of kidney disease or other likely causes of proteinuria, suggesting that albuminuria and/or proteinuria were underdiagnosed in our group of patients. Those with cardiovascular disease, kidney disease, or diabetes showed the greatest predictive value of a positive test for albumin or protein by dipstick. Dipstick testing for albumin, protein, and creatinine had good or excellent agreement with quantitative methods. The dipstick tests were easy to use, simple, and low in cost, and can serve well for point-of-care testing.