In this report we describe a case of severe chronic infantile neurologic, cutaneous, articular (CINCA) syndrome with a novel G307V cryopyrin mutation and all of the characteristic clinical and laboratory features of this autoinflammatory disease. There was no clear response to standard therapies, including human interleukin-1 (IL-1) receptor antagonist (anakinra) and soluble tumor necrosis factor receptor (etanercept). The patient finally had a partial clinical response (reduction in fever and irritability) and complete laboratory response (improved C-reactive protein and serum amyloid A levels) to humanized anti–IL-6 receptor antibody (MRA), but died from congestive heart failure and interstitial pneumonia 2 months after initiation of therapy. We serially measured the serum cytokine levels and expression of NF-κB activation in the patient's peripheral blood mononuclear cells before and during consecutive therapies. Pathologic examination of autopsy specimens was also performed. This case illustrates the continued difficulty in management of patients with CINCA syndrome and the complexity of the inflammatory pathways in this disorder.