His background history included a permanent pacemaker implantation (PPM) and a recent bioprosthetic aortic valve replacement (AVR) with mitral valve repair. Two months following cardiac surgery, a C-reactive protein (CRP) level was found to be over 100 mg/L, with no obvious infectious foci identified. One month later, he was also found to have an abnormal skin rash with tender papules, which was attributed to a diagnosis of erythema nodosum. This evidence concerns the gene CRP and Erythema nodosum.