IL-18 is uniquely elevated in autoinflammatory patients referred for MAS. (A) IL-18, (B) IL-18BP, (C) CXCL9, and (D) free IL-18⁴²  were measured in serum samples from a broad referral cohort of patients with autoinflammatory disease. Acronyms, genetic associations, and statistical testing can be found in supplemental Table 1 and Data supplement B. Patients per group are indicated in parentheses, with multiple samples gathered longitudinally from some patients (eg, Figure 3; supplemental Figure 3). Gray bars, range of values measured in HC samples. CANDLE, chronic atypical neutrophilic dermatosis, lipodystrophy, elevated temperature; CNO, chronic nonbacterial osteomyelitis; DADA2, deficiency of ADA2; DIRA, deficiency of IL-1 receptor antagonist; FMF, familial Mediterranean fever; PAAND, pyrin-associated autoinflammation with neutrophilic dermatosis; SAVI, STING-associated vasculopathy of infancy; TRAPS, TNF receptor–associated periodic syndrome; undiff, undifferentiated; XIAP-def, XIAP-deficiency.