This is a 55 yo female of Irish descent with a history of psoriasis and psoriatic arthritis on Enbrel, who presented with a 3-day history of indurated erythematous plaques on the buttocks.  The patient reported that the eruption was preceded by 1-2 days of fever and flu-like symptoms.  She has had 2 prior episodes of similar symptoms, lasting a few days to a week followed by spontaneous resolution.  She has had no recent change in medications.

Dr. Moschella saw the patient and suggested a diagnosis of hibernian fever...