A case of eosinophilic pneumonia. Unusual immune complex vasculitis in the skin.

This report concerns a 28-year-old woman with biopsy-proved eosinophilic pneumonia and cutaneous vasculitis. The skin biopsy specimen contained prominent granular deposits of IgM and C3 in dermal vessels, and elevated circulating immune complexes were detected. The association of cutaneous immune complex vasculitis with circulating immune complexes in chronic eosinophilic pneumonia is unusual and to our knowledge has not been previously reported. While the pathogenesis of chronic eosinophilic pneumonia is unknown, circulating immune complexes may represent a mechanism in the development of tissue eosinophilia.