Churg-Strauss Syndrome Following Vaccination Against 2010 Influenza A (H1N1): A Case Report.

PURPOSE AND BACKGROUND: Churg-Strauss syndrome (CSS) is a systemic inflammatory disorder characterized by asthma, transient pulmonary infiltration, hyper-eosinophilia, and systemic vasculitis. Reported triggering factors include infections, drugs, allergic desensitization, and vaccinations, although cases involving the latter two are extremely rare. Herein, we describe a patient who developed CSS after receiving an H1N1 vaccination. CASE REPORT: A 55-year-old woman presented with fever, skin eruptions, and sensory impairment of her feet within one week after an H1N1 vaccine injection. A chest X-ray showed pulmonary infiltrations in both lower lung fields. Eosinophilia was noted in a hematological test, and an electrophysiological study revealed a pattern of mononeuritis multiplex. A skin biopsy was performed which revealed palisading necrotizing granuloma around a degenerated dermis and eosinophilic infiltration of the blood vessel walls. These findings combined with the hematological and electrophysiological findings met the criteria of CSS according to the American College of Rheumatology. The patient recovered well after steroid treatment. CONCLUSION: This case highlights the possibility that the H1N1 vaccination can trigger CSS. Due to the rarity of reported autoimmune events after vaccine administration and the obscure causal association between autoimmunity and a vaccine, further post-marketing surveillance and research are necessary to clarify the relationship and identify risk factors.