I'd love to help with your question!
During the daytime, I'm a pediatric nephrologist (kidney doctor), so I see kids like your grandson every day. My suspicion is that you don't have anything to worry about... but let me explain what I think you should do and why.
First, let me explain why we worry about protein in the urine.
As you know, our kidneys are basically big filters: blood goes to the kidneys, and it's the kidney's job to keep things that we need to save in the bloodstream while filtering waste products into the urine.
Our blood is filled with useful proteins, and so under normal circumstances, our kidneys want to keep those things in the blood. That means that they should stay on the blood side of the filter and never get into the urine in the first place.
When there is protein in the urine, it makes us worry that something is wrong with the little filters (called glomeruli) that make up the kidney. (You can make an analogy to a coffee filter. If the coffee filter is intact, no coffee grounds end up in your coffee... but if there is a little tear in the filter, you'll have some grounds in your coffee.)
However, sometimes when children are sick with fever
, they'll leak small amounts of protein into the urine. When they're well, that goes away - so there's no problem with the filters. (As a rule of thumb, any kind of protein in the urine that goes away is not a problem, because if the filters are damaged or broken, they'll leak protein all the time - think back to the coffee filter analogy!)
The amount of protein in your son's urine is pretty small, so between that and the fact that we obtained the urine samples when he was sick, I'm optimistic that it's going to go away on its own.
What I would recommend is that your son's pediatrician quantify the amount of protein in the urine. The urine dipstick test that we use in the office is okay for getting a rough idea of the amount of protein in the urine, but before we embark on more diagnostic workup, we need to be more precise. What his pediatrician should do is have the lab measure (in miligrams) the amount of protein in the urine, and compare that to the amount of creatinine (a waste product) in the urine. (This is called the protein-to-creatinine ratio, and allows the protein to be standardized to the amount of "urine" in the urine. Trust me, his pediatrician will know what I'm talking about!)
If his protein-to-creatinine ratio is abnormal, then he should see a nephrologist. If it's normal, then you don't need to worry about the protein any more.
I should also point out that protein in the urine shouldn't cause your grandson any symptoms - that is, protein won't make him say that his privates hurt. So if he's still complaining about that, we need to seek another explanation for it. (If that is an ongoing issue, I'd be happy to make some additional recommendations, but probably the first thing to do would be get a kidney ultrasound to be sure that his anatomy is normal and that he doesn't have something unusual like a stone.)
The botXXXXX XXXXXne is this:
I doubt that the protein in the urine is a major issue, and I don't think it's something you need to worry about. I think it deserves a bit more evaluation before we pass it off, but I honestly don't think we're going to find anything serious.
I hope that this information is helpful to you. If I've answered your original question, please be sure to rate the quality of my response - your feedback does matter! And if you have any more questions - now or in the future - please do not hesitate to ask.
Best wishes to you and your grandson...