Acute Generalized Exanthematous Pustulosis in a Patient With Crohn's Disease Being Treated for Streptococcal Pharyngitis and Sternoclavicular Joint Abscess.

Acute generalized exanthemous pustulosis (AGEP) is a rare skin reaction most commonly due to an adverse drug reaction. The rash is characterized by the sudden onset of diffuse pustules on a maculopapular rash. We present a case of a 62-year-old female treated with cephalexin for streptococcal pharyngitis who was admitted with the characteristic rash over her chest, abdomen, arms, and legs that started four days after starting the antibiotic. The diagnosis was further confirmed with a punch biopsy of the affected skin. The rash quickly resolved after discontinuing cephalexin. The patient's course was complicated by findings of a left sternoclavicular joint abscess requiring surgical debridement and resection along with an extended course of intravenous antibiotics. It was felt the abscess was caused by hematogenous spread from the patient's original streptococcal infection as opposed to being directly due to the AGEP, which further added to the complexity of the patient's case.