Erythema Nodosum: A Manifestation of Salmonella Infection.

Erythema nodosum is a delayed-type hypersensitivity reaction with an unknown trigger in the majority of cases. It is characterized by the development of erythematous tender nodules on the shins. Septal panniculitis without vasculitis is a characteristic histopathological finding. We report the case of a 26-year-old woman who presented with a four-day history of an erythematous swollen left lower limb. She was treated with intravenous clindamycin for suspected cellulitis. However, her symptoms persisted. Punch biopsy revealed findings consistent with erythema nodosum. Two days later, she developed colicky abdominal pain associated with non-bloody diarrhea. Stool culture yielded Salmonella enterica serotype enteritidis. Two days after discharge, she presented again with a right breast abscess for which she underwent incision and drainage along with antibiotic therapy. After discharge, she was symptom-free with complete resolution of the cutaneous lesions. The presented case is unique as it had multiple clinical manifestations of Salmonella infection including erythema nodosum, diarrhea, and presumably a breast abscess. It should be kept in mind that gastrointestinal symptoms are not necessarily the initial presentations of Salmonella infection.