Aim To report the first case of cardiac tamponade related to Infliximab induction therapy in an Ulcerative Colitis patient. Methods Review of published case reports. Results This complication was likely due to a type 3 hypersensitivity immune-complex reaction resulting in a reactive pericardial effusion Discussion Though rare, this case demonstrates how autoimmune reaction to anti-TNF𝛼 therapy can initially mimic infection, as our patient presented with tachycardia, hypotension, raised inflammatory and infective markers and fever.