IFNG and cutaneous mastocytosis: The median concentration of IFN-γ (Fig. 1A; see also Table S1 in the supplemental material) was significantly (P = 0.0019) higher in acute CM cases (17.3 pg/ml) than in controls (2.32 pg/ml) and in acute SMA (P = 0.0248) and acute UCM (P = 0.0295) cases, and these levels then decreased significantly (P < 0.001) in convalescence (Fig. 2A).