Six cases of refractory pruritus and histologic dermal hypersensitivity reaction successfully treated with dupilumab

Dermal hypersensitivity reaction (DHR) is a histopathologic finding that characterizes many different clinical diagnoses, such as chronic pruritus of unknown origin (CPUO), drug reactions, arthropod bite reactions, spongiotic dermatitis, bullous pemphigoid, scabies, urticarial erythema multiforme, dermatitis herpetiformis, eosinophilic folliculitis, and urticarial vasculitis.1 Because DHR is a histologic rather than a clinical diagnosis, no single treatment regimen has been consistently used, and treatment has rather focused on addressing the underlying cause.