Proteinuria (Bubble urine) - Polycystic Kidney Disease (PKD)

Due to the filtration of the glomeruli and the re-absorption of the renal tubules, under normal circumstances, the protein in urine is small amount (<150mg/d) and the protein qualitative check is negative. When the protein in urine excess 150mg/d, it is proteinuria and it can be checked out in routine urine test. And if the leaked protein is more than 3.5g/24h, it is massive proteinuria which is the typical symptom of nephrotic syndrome.

Since in the early stage the renal tubules are damaged, therefore the proteinuria is mild and it usually will not develop nephrotic syndrome. There are about 20% to 40% patients among those that are between 20 to 40 have mild and persistent proteinuria, however the urine protein is less than 1g/d. With the continuous enlargement and increase of the cysts, they will oppress and replace normal renal tissues and when the glomeruli are damaged, the proteinuria will be worsened.

Generally speaking, persistent proteinuria indicates renal damages and the amount of proteinuria can to a certain degree reflects the severity of PKD. Long term proteinuria without effective treatment will in turn worsen the kidney functions, therefore positive and proper treatments should be received as early as possible.