Excess protein in the urine is called as
proteinuria and usually it is albumin that is lost through urine. Some protein is normal
in the urine. A 24 hour estimation of protein loss in urine would be optimal to estimate the level of proteinuria.
Conditions which can cause proteinuria are nephrotic syndrome, glomerulonephritis, dehydration, collagen vascular diseases, strenuous exercises, diabetes mellitus, infections, multiple myeloma etc.