I'm a 36 year old male, and about 2 months ago I had a positive proteinuria test, which I received after experiencing edema in my feet, one day. I did a follow up test at my doctor's office a couple days later and had no detectable protein in my urine. What I've noticed since then is if I urinate after laying down for an hour or more (mostly to reduce the edema in my feet) I have much less to no bubbles in my urine. If I urinate after sitting for a couple hours or walking around I have a significantly increased amount of foam. I'm currently waiting to see a nephrologist, which I won't get into for another month. Does the decrease in foam suggest orthostatic proteinuria? If I have that what could be the cause of my edema? Any tests I should run prior to seeing the nephrologist to confirm this?