Pretty Good News
One of D-boy's kidneys is larger than the other (but not beyond a standard deviation). He has minor reflux from his bladder to one kidney (I didn't think to ask if it was the big or little one) which is causing his infections. Apparently this is almost entirely a male problem--with female plumbing, things just work themselves out.
He's going to a specialist soon but unless he gets another dose of bacteria, he should be fine.
He hasn't slept more than fifteen minutes at a time for the last three nights so it's nice to know that at least one part of his body is working half-way decently.