Elevated protein in urine

[SoloRiver]

Fly had a recent trip to the vet and urinalysis indicated elevated levels of protein in her urine (value was a 2+, normal/trace is 0/1+ and anything over that is considered significant). She had a urinalysis last year that was clear. Other than having poop of inconsistent, er, texture unless she eats one particular food (Natural Balance), she has no obvious health issues and appears, for all intents and purposes, to be "bursting with health." Her bloodwork, taken at the same time, was totally normal.

 

The vet wants to test her again for Lyme. She had a test last year that was apparently positive enough to indicate exposure but not positive enough to indicate disease. Is there anything else I should be panicking about? From what I've read it doesn't appear to be serious renal disease since she has none of the other symptoms.

 

The reason for Fly's vet visit is that she has a small mammary tumor next to one nipple. These are so often benign that I'm not going to start freaking out until someone tells me to. She's getting it removed and biopsied next week.

 

Any comments or advice?

[AK dog doc]

Since her renal values were normal, it seems unlikely that the protienuria is an indicator of significant renal disease. Was the urine sample a free-catch? If so, the source of the protein could be anything from the kidney on down to and including the vaginal vault. If it was a cystocentesis or a catheter collection, then the possible sources would stop at the bladder and/or urethra. Taking urine via cysto does sometimes mean that there's a little protein contamination from the needle stick, though.

 

If she does have a little bit of vasculitis or inflammation from one of the rickettsias (etc), that could be responsible for a little spike in proteinuria, either from leaking from the capillaries or from filtering out immune complexes; and we shouldn't forget that there might be some transient causes that are not likely to have a long-term impact on the dog. I don't think I'd be leaning toward this being of renal origin, myself; I think I'd be looking elsewhere for causes, which you're already pursuing with the serology. It's even possible it's secondary to the mammary mass. You're right that in dogs approximately 50% of mammary tumors are benign, and of the malignancies, many (well better than half, in my experience) are readily curable with a single surgery. However, while they are present, even if they are mild-mannered in general, it's possible that they might alter urine protein excretion on a short-term basis, as a paraneoplastic syndrome. (The most usual tumor to spike protein in the urine in dogs - apart from tumors of the urinary system itself - is probably multiple myeloma, not breast cancer, but tumors can behave in atypical manners if they so choose, the little monsters. :mad: )

 

Besides the serology, you might consider doing a re-check on the urine protein a few weeks after resecting the tumor to see if the proteinuria is persistent. But as far as things to panic about, I'm not coming up with much, at least not at the moment. I hope Fly's surgery is uneventful and the histo report is good news. There's a way better than even chance it will be, but I'll keep my fingers crossed for her anyway.

[ArmyDoc]

Boo-Hiss, Dog Doc said the "M" word.

 

There are some causes of proteinuria in humans that are just plain silly; like benign positional proteinuria. For some reason, some people leak protein after being upright but not supine. You'd think this would select against men (who can pee standing up) but it's benign so no such luck. It's just a factoid, and has no particular consequence... unless you sleep standing up.

 

I imagine that in dogs as well, one could produce a very long list of reasons to have a little proteinuria other than cancer. The "M" word would not be at the top of my list. I betcha this will turn out to be True, True and Unrelated - the dulling of Occam's Razor.

 

-kevin-

[AK dog doc]

The "M" word...? Now, would that be mammary, mass, malignancies, mild-mannered, multiple myeloma, or monsters? (I'll bet it's "monsters". I'll try never to say it again. )