Three sites have the word disease in the description, not a lot. Two of those have the word Disease in the title.
Those ODP titles represent the title of the site according to ODP standards - so if you do not like the use of the word disease, I think you have to talk to the site/group owner and get them to change the title of the site / Yahoo Group
Addison's disease is the correct medical name for a rare endocrine disorder that affects 1 in 100000 people.