CRP and pericardial effusion: The clinical manifestation during the recurrent event of pericarditis was less prominent or attenuated when compared to the initial event—ECG signs (ST elevation 12% vs. 26%; p = 0.006, Knuckle sign 13% vs. 33%; p < 0.001, ST larger in lead L2 than L3 4% vs. 19%; p < 0.001), pericardial effusion moderate and above (11% vs. 30%; p = 0.02), and inflammatory markers (mean peak CRP levels 66 mg/l vs. 97 mg/l; p < 0.001).