Overlap between maculopapular exanthema and drug reaction with eosinophilia and systemic symptoms among cutaneous adverse drug reactions in a dermatology ward

Abstract

In a retrospective study to characterize cutaneous adverse drug reactions (CADR) among in-patients, we experienced cases with overlapping features between maculopapular exanthema (MPE) and DRESS.To characterize a group of patients presenting with exanthema and few systemic symptoms without fulfilling the RegiSCAR criteria for probable DRESS, designated as overlapping MPE-DRESS (MP/DR).Comparative analysis of clinical and laboratory features of patients with MPE, MP/DR and DRESS during 5 years (2008-12).We identified 132 in-patients (85F/47M, mean age 64,0±17,7 years) with CADR, 37 with DRESS (28,0%), 28 with MPE (21,2%), 34 with MP/DR (25,8%) and 33 (25%) with other patterns. There was no significant difference in gender, age or concomitant diseases between MPE, DRESS and MP/DR. Allopurinol was the main culprit for DRESS (40,5%) and MP/DR (29,4%), while antimicrobials were the leading culprit in MPE (35,7%). In MP/DR the latency period (18,06±13.17 days) was significantly longer than in MPE, however shorter than in DRESS. Although hospitalization time was similar to DRESS (13,26±7,41 days), the duration of therapy and follow-up in MP/DR was shorter. Exanthema or erythroderma was frequently associated with facial oedema both in MP/DR and DRESS (73,5% and 89,2%) whereas only in 42.0% of MPE. Histopathology in MP/DR showed keratinocyte vacuolization and a perivascular and interstitial infiltrate of lymphocytes, eosinophils and neutrophils similar but milder than in DRESS with less interface dermatitis, exocytosis or spongiosis. DRESS was associated with liver involvement and eosinophilia in 78.4% for both parameters, whereas these occurred only in 64,7% and 11.8% respectively in MP/DR despite similar severity.We identified and characterized an overlapping pattern between MPE and DRESS, with fewer systemic symptoms than DRESS, but when present with similar severity, suggesting a minor form of DRESS. There may be a continuum spectrum between MPE and DRESS. This article is protected by copyright. All rights reserved.