Histopathology of Severe Drug Eruptions

Abstract

In diagnosing cutaneous adverse drug reactions, the histopathological findings must be examined, and those findings provide insight into the pathomechanisms of these disorders. The characteristic histological findings of Stevens–Johnson syndrome and toxic epidermal necrolysis are crucial for diagnosing and discriminating from erythema multiforme. Drug-induced hypersensitivity syndrome and exanthema in drug reaction with eosinophilia and systemic symptoms each shows variable histopathological findings, which may have a partial relationship with the clinical features. Acute generalized exanthematous pustulosis presents spongiform superficial epidermal pustules associated with edema of the papillary dermis and abundant mixed perivascular infiltrates.