How does proteinuria cause edema?

Question

Quizplus · Accepted Answer

Proteinuria results in the loss of plasma albumin, which contributes significantly to the plasma oncotic pressure that keeps water within the capillaries. Hence, the decrease in the plasma oncotic pressure leads to the movement of fluid into the interstitial spaces, causing edema. A and B are not correct as loss of plasma albumin from the urine does not obstruct the collecting tubules or interfere with ADH stimulation. C is also incorrect as the renin-angiotensin-aldosterone system is activated as a response to decreased blood volume, rather than the loss of plasma albumin specifically.

How Does Proteinuria Cause Edema