dying disease

a fatal condition consisting of other smaller diseases, prime examples being "shot in a vital organ disease", or "crushed by a flaming helicopter disease".
The symptoms can range from completely underlying to incredibly painful, and the life expectancy for a dying disease patient can range anywhere from 0.5 seconds to 20 years.

"I just came back from the doctor's, and he diagnosed me with dying disease."
"Maybe it's because you've got rebar through your forehead"