During febrile attacks in patients with HIDS [8] or MKD [2], there is a strong acute-phase response, with substantially elevated concentrations of white blood cell (WBC) count, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR), especially CRP and ESR (Table 1). The gene discussed is CRP; the disease is hyperimmunoglobulinemia D with periodic fever.