Severe serum sickness after H1N1 influenza vaccination.

In this study, the case of a 48-year-old man with severe serum sickness reaction in response to H1N1 influenza immunization is reported. He presented with renal failure and several of the classic signs reported in early descriptions of serum sickness by Clemens von Pirquet and Bela Schick including lymphadenopathy, urticarial skin eruption and facial edema. Serum immunologic studies and tissue histology/immunohistochemistry assisted in firmly establishing the diagnosis in this case. With appropriate therapy, the patient's rash, edema and lymphadenopathy resolved and normal renal function returned. This first reported case of severe serum sickness to H1N1 vaccine is particularly important in light of the Centers for Disease Control and Prevention's recommendation for universal vaccination against influenza, including H1N1, in patients 6 months and older. With increasing numbers of patients receiving this vaccine, even rare adverse reactions may be experienced by numerous individuals. It is imperative that clinicians remain vigilant about possible reactions and quickly institute appropriate therapy.