HPI: The patient describes mild acne before leaving for college in late August 2012. He did being a new electric razor with him. Shortly after arriving at school, he developed an inflammatory process on his chin. He was treated with Keflex for > one month without relief.
O/E: Papules + pustules on the chin. Rest of exam unremarkable.
Discussion: This young man had acne which had been treated with cephalexin for one to two months. It has not improved and the presentation with pustules suggested gram negative acne. His college health center's provider wisely performed a bacterial culture which grew Serratia. Initially, I was thinking of prescribing ciprofloxicillin, but the literature suggests that isotretinoin may be the treatment of choice.
Followup after five months isotretinoin:
|Photo from James and Leyden's article, above|