Sweet's syndrome associated with myelodysplasia: possible role of cytokines in the pathogenesis of the disease.

The clinical course of a 56-year-old female patient with Sweet's syndrome (SS) preceded by a myelodysplastic syndrome (MDS) is described. During the acute phase of the disease with high remittent fever, painful skin lesions and maximal leucocytosis IL-6 and G-CSF serum levels were extremely high, while TNF-alpha was only slightly elevated and gamma-interferon and IL1-beta were not increased. On clinical improvement IL-6 serum levels rapidly fell, whereas G-CSF values already slightly elevated before the manifestation of the disease slowly declined. High G-CSF levels triggered by a yet unknown factor could explain the leucocytosis, neutrophilic dermatosis and skin lesions in SS, while IL-6 probably induced the associated clinical symptoms of fever and pain.