RT Book, Section A1 Shah, Ankoor A1 St. Clair, E. William A2 Kasper, Dennis A2 Fauci, Anthony A2 Hauser, Stephen A2 Longo, Dan A2 Jameson, J. Larry A2 Loscalzo, Joseph SR Print(0) ID 1120813173 T1 Rheumatoid Arthritis T2 Harrison's Principles of Internal Medicine, 19e YR 2014 FD 2014 PB McGraw-Hill Education PP New York, NY SN 9780071802154 LK accesspharmacy.mhmedical.com/content.aspx?aid=1120813173 RD 2021/03/08 AB Rheumatoid arthritis (RA) is a chronic inflammatory disease of unknown etiology marked by a symmetric, peripheral polyarthritis. It is the most common form of chronic inflammatory arthritis and often results in joint damage and physical disability. Because it is a systemic disease, RA may result in a variety of extraarticular manifestations, including fatigue, subcutaneous nodules, lung involvement, pericarditis, peripheral neuropathy, vasculitis, and hematologic abnormalities.