Abstract
Interstitial pneumonias in RA have wide range of diversity. Among them, OP and DAD are acute/subacute types and trace similar clinical course to idiopathic counterparts. UIP and NSIP are chronic fibrosing types. The rate associated with chronic IP in RA is 5-15%. UIP of RA has poor prognosis than NSIP of RA, and has similar poor prognosis compared with idiopathic one. Unlike IPF, lung cancer and infection are major cause of death than IP itself.