Serum IFN-γ-inducible chemokines CXCL9 and CXCL10 are elevated in non-immediate drug hypersensitivity reactions

The recruitment to the skin of drug-responsive T cells is responsible for the inflammatory profiles of non-immediate drug hypersensitivity reactions (niDHRs). Maculopapular exanthema (MPE) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) have quite distinct T cell infiltrating patterns.

To investigate serum levels of CXCL9, CXCL10 and IFN-γ in patients with niDHRs, including MPE and SJS/TEN, to evaluate correlations between the cytokines, and to determine whether the inflammatory factors correlate with clinical severity in patients with SJS/TEN.

Twenty-four patients with SJS/TEN, 24 patients with MPE, and 24 healthy donors with good tolerance to the drugs involved in the drug reactions were recruited into the study. The modified severity-of-illness score for TEN (SCORTEN) and detachment of body surface area (dBSA) were used to assess the clinical severity of SJS/TEN. Serum levels of CXCL9, CXCL10 and IFN-? were determined by ELISA.

The niDHRs group, SJS/TEN and MPE subgroups all exhibited significantly higher levels of CXCL9, CXCL10 and IFN-γ compared with the control group (P < 0.001). Serum IFN-γ levels were positively correlated with CXCL9 levels and CXCL10 levels in patients with niDHRs (rs = 0.576, rs = 0.449, P < 0.05). None of the levels of CXCL9, CXCL10 and IFN-γ had any correlation with modified SCOTEN index or dBSA in SJS/TEN group.

The results suggest Th1 cytokine IFN-γ and chemokines CXCL9 and CXCL10 may play roles in the pathogenesis of niDHRs.