Iohexol-Induced Acute Generalized Exanthematous Pustulosis (AGEP): Case Report

Abstract

Acute generalized exanthematous pustulosis (AGEP) is a rare adverse drug reaction characterized by numerous non-follicular sterile pustules overlying edematous, erythematous plaques. The majority of AGEP cases are associated with antimicrobial medications, although other agents and etiologies have also been implicated. Here, we report a patient with recurrent angioimmunoblastic T-cell lymphoma (AITL) who presented with a pruritic and widespread pustular eruption one week following computed tomography (CT) with iohexol contrast administration. Notably, she had a documented prior mild reaction to contrast medium and was appropriately pre-medicated with diphenhydramine and prednisone before imaging. Biopsy revealed intra-epidermal pustules, epidermal spongiosis, and dermal infiltrate of lymphocytes, neutrophils, and some eosinophils – histological findings consistent with AGEP. Systemic and topical corticosteroids plus topical mupirocin resulted in complete resolution of symptoms. While cutaneous reactions to iodinated contrast are common and often self-limited, severe manifestations such as AGEP must be considered particularly in patients with a history of prior contrast allergy.