eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2020-08-04 8 11 433 434 10.12691/ajmcr-8-11-15 AJMCR202081115 article Nazish Malik namalik@conemaugh.org 1 Munawwar Hussain 1 Cyril Nathanial 1 Department of Internal Medicine, Conemaugh Memorial Medical Center, Johnstown, PA Acute pericarditis is common and often mimics acute coronary syndrome (ACS) in clinical as well as electrographic presentation. It is essential to differentiate between these two conditions, as treatment is different. A rare form of acute pericarditis, regional pericarditis, can be elusive, especially when it presents on EKG as an acute ST-segment elevation MI of a particular wall. We present a case of localized (regional) pericarditis in a 66-year-old female with a history of rheumatoid arthritis who presented to the emergency department with localized left-sided chest pain. Her arrival EKG showed acute anterolateral wall ST-segment elevation. The patient received diagnostic cardiac catheterization, treatment with colchicine and steroid, which produced resolution of symptoms and EKG changes. http://pubs.sciepub.com/ajmcr/8/11/15/ajmcr-8-11-15.pdf pericarditis ST-segment elevation colchicine