In the present case, the diagnosis was established by integrating proposed clinical features from established classification systems such as the Eurofever/PRINTO criteria (36), the presence of the classic triad (urticarial rash, aseptic meningitis, and arthropathy), rigorous exclusion of alternative diagnoses, and definitive genetic confirmation of a pathogenic NLRP3 mutation (37). The gene discussed is NLRP3; the disease is aseptic meningitis.