Proteinuria

Abstract

Proteinuria is not only a cardinal sign of primary and secondary nephropathies, but also an independent pathogenic factor of progression of these diseases. Along with the serum creatinine level, red blood cell urine test, and renal ultrasound, qualitative and quantitative data on proteinuria belong to the basic nephrological evaluation. In routine practice, the dipstick test is used for the screening of proteinuria; this, however, cannot detect microalbuminuria, Bence-Jones proteinuria (free light chains, for instance, in multiple myeloma), and signs of tubulointerstitial diseases. For a more precise evaluation of albuminuria and/or proteinuria, the urine albumin/creatinine ratio test or 24-hour urine protein excretion test can be recommended.