Drug reaction with eosinophilia and systemic symptoms (DRESS): A histopathology based analysis.

ABSTRACT

Background: The data on the histology of cutaneous lesions of drug reaction with eosinophilia and systemic symptoms (DRESS) is limited. Aims: To study the histopathology of cutaneous lesions of drug reaction with eosinophilia and systemic symptoms (DRESS) and to identify any features with diagnostic or prognostic signifi cance. Methods: All patients admitted to the dermatology ward of government medical college, Kozhikode from January 1, 2014 to December 31, 2014 with probable or defi nite DRESS as per the RegiSCAR scoring system and who were willing to undergo skin biopsy were included in this prospective study. Results: The study population comprised of nine patients. The consistent histological fi nding documented was the predominantly lymphocytic dermal infl ammatory infi ltrate. Four of the fi ve patients whose histology revealed focal interface dermatitis and keratinocyte vacuolation with or without apoptotic keratinocytes, had elevated liver transaminases. Tissue eosinophilia was associated with disease fl ares. The presence of atypical lymphocytes in peripheral smear and histological evidence of dense dermal infl ammatory infi ltrate showed an association with hepatic involvement. Limitations: The main limitations of our study were the small sample size and our inability to carry out a detailed immunohistochemistry work-up. Conclusions: In the appropriate setting, varying combinations of epidermal hyperplasia, spongiosis, parakeratosis and individually necrotic keratinocytes in the background of lymphocyte predominant dermal infi ltrate (with some atypia) favor a diagnosis of drug reaction with eosinophilia and systemic symptoms. Female sex, the presence of atypical lymphocytes in peripheral smear, dense dermal infl ammatory infi ltrate, tissue eosinophilia and interface dermatitis with or without keratinocyte necrosis was associated with a poor prognosis.