[Macrophage migration inhibition factor as a diagnostic aid in drug eruptions]

The diagnostic value of the macrophage migration inhibition factor (MIF) test was evaluated in 90 patients with the clinical diagnosis of drug eruption. There were 40 males and 50 females who ranged in age from 15-84 years (mean 61.0). Controls were 120 patients being treated with drugs without adverse reactions and 21 patients with dermatologic disorders unrelated to drugs. Positive MIF responses for 1 or more drugs were observed in 71.1% of the patients with drug eruptions as compared to 4.2% and 9.5% of the control groups, respectively (p less than 0.001 for both). The proportion of positive MIF responses in those in whom drugs were implicated (45.2%) was significantly greater (p less than 0.0001) than in those with eruptions in whom drugs were not implicated (18%). The MIF test may be of aid in the diagnosis of drug eruptions and in the identification of the offending drugs.