Systemic contact dermatitis following oral neomycin therapy.

Systemic contact dermatitis (SCD) describes a hypersensitivity skin reaction following systemic re-exposure of an allergen in previously sensitized patients. Neomycin is an aminoglycoside antibiotic that, when taken orally, suppresses intestinal bacteria and is used in preoperative bowel surgery to reduce the risk of infection. While oral neomycin has been commonly associated with adverse reactions like nausea, vomiting, and Clostridium difficile-associated colitis, the poor intestinal absorption of oral neomycin makes systemic contact dermatitis an unusual adverse reaction. Herein we present a rare case of systemic contact dermatitis following oral neomycin administration.

Squamoid Eccrine Ductal Carcinoma: An Aggressive Mimicker of Squamous Cell Carcinoma.

Squamoid eccrine ductal carcinoma (SEDC) is an uncommon cutaneous adnexal malignancy that has the potential for an aggressive clinical course. The authors present a case of SEDC that resulted in widespread metastases and death. The clinical, histological, and immunohistochemical features of SEDC and several entities on the differential diagnosis are reviewed.