Lymphomatoid papulosis and its relationship to "idiopathic" hypereosinophilic syndrome.

Persistent hypereosinophilia, endomyocardial fibrosis, and a recurrent self-healing papulonodular eruption with the histologic features of lymphomatoid papulosis are described in three patients. One patient died after developing an acute myeloblastic transformation in the eosinophil series. Immunocytochemical studies of cutaneous lesions in two of the patients suggested a mature T-cell phenotype with a predominant population of CD4-positive cells. Immunostaining of cutaneous tissue with monoclonal antibodies BE1 and BE2 yielded negative findings. Because it is now known from in vitro studies that T lymphocytes secrete the eosinopoietic factor, interleukin 5, it is possible that the cutaneous lesions, hypereosinophilia, and associated endomyocardial fibrosis were induced by transformed helper T lymphocytes in these three patients.