Has anyone considered what the effect on his brain was when his heart stopped in the ICU? My sister drowned and was without oxygen for several minutes before she was resuscitated by the paramedics. This incident had a very negative affect on her motor skills and thought processes. I wonder if when you heart stops if a similar result isn't possible.
My wife has kidney failure. It is not bad enough yet for dialysis, but it still causes a raft of other problems for her. No doubt Derek's health is severely compromised right now. I suspect this is reflected in his face. The stress of being this sick alone would wear on one's appearance.
There been a lot of suggestion here that he is still using drugs and shooting oil into his body. He looks small as compared to how he once looked. The lumpiness could be scar tissue from previous times. If he isn't holding water, which it appears he isn't, this might make those scared areas all the more apparent.
I found myself wondering while looking at these probably recent photos, how he would have looked today, had he not gotten sick. It is also interesting to consider how he might have looked had he not taken bodybuilding and PED's to the level he seems to have. He was a relatively nice looking guy not too many years ago. Everyone ages differently, but he has not aged well at all. It is really very sad.