L.S.
At this age it is a problem for the doctor. Aside from the sheets and hygeine, that is normal. All 3 of my boys have to be told to take a shower, and USE SOAP, and WASH your hair, AND put on clean clothes. That doesn't bother me. What bothers me about this situation is his age. That is not normal for a 10 year old to wet the bed. He definately needs to go to the doctor. Studies have shown that it is probably because his bladder is not growing as fast as he is. But there is medicine that can help.
I would hesitate to punish him for something that he cannot control. Especially if he is in a deep sleep. However, I would definately make him responsible for getting up, stripping the bed, starting the washer and showereing every moring to start his day. He probably would not be so secretive if he knew he was not going to get in trouble. It's not like he wants to pee the bed and make you mad. He just can't help it. Even whether he sneaks drinks, he should be able to hold his urine. Or wake himself up with the urge to void. He doesn't wake up with the urge to void because he has already emptied the bladder in this sleep. I don't think a deep sleep would be the culprit either. At this age continued bed wetting is a sign to go to the doctor. Especially, if what you already do isn't working.
Good luck,
L.