collagen disease

Definition of collagen disease
National Cancer Institute

collagen disease

(KAH-luh-jen dih-ZEEZ)
A term previously used to describe chronic diseases of the connective tissue (e.g., rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis), but now is thought to be more appropriate for diseases associated with defects in collagen, which is a component of the connective tissue.

Source: NCI Dictionary of Cancer Terms