Dorek Syndrome is a rare and deadly Ferengi disease. Only one in five million Ferengi are diagnosed with Dorek Syndrome, and diagnosis can come with only a few days to live.
Quark was mistakenly diagnosed with Dorek Syndrome in 2372 by Doctor Orpax. Upon learning this, Quark wanted to sue Orpax for malpractice. (DS9: "Body Parts")