Abstract

Iododerma is a skin eruption attributable to an accumulation of systemic iodine, commonly caused by renal dysfunction. Most commonly, iododerma presents as acneiform eruption; however, edematous, bullous, or hemorrhagic lesions can develop and evolve to vegetative nodules in advanced disease. Histopathological findings are typically nonspecific but can include a polymorphonuclear cell infiltrate with a few eosinophils, mast cells, and plasma cells. We present a case of bullous eruption in a patient with a history of end-stage renal failure and recent contrast angiogram. A few days following contrast angiogram, patient presented with a large, firm nodule with central ulceration on the lateral aspect of her tongue and a violaceous, tender, flat-topped bullous plaque with surrounding erythema on her right hand overlying the fifth metacarpophalangeal joint. The biopsy of the hand lesion showed neutrophilic infiltrate with haloed structures resembling cryptococcus. However, fungal stains were negative. Such haloed artifacts have been previously reported in cases of iododerma and represent degenerating histiocytes. While iododerma is a diagnosis of exclusion, this case is a reminder to suspect iododerma when these artifacts are encountered.