Protein and casts in the urine

Under normal circumstances, due to the filtration effect of the glomerular filtration membrane and the reabsorption effect of the renal tubules, the content of protein (mostly proteins with small molecular weight) in the urine of healthy people is very small (less than 150 mg per day ), When the protein is qualitatively examined, it is negative. In pathological conditions, such as those with kidney disease, the filtration effect of the filtration membrane will change. One of the typical diagnostic criteria for chronic nephritis, purpuric nephritis, lupus nephritis, and diabetic nephropathy is that during routine urine tests, proteinuria and hematuria are abnormal at the same time, and kidney disease is highly suspected.