Serum cytokine responses during acute human granulocytic ehrlichiosis

Human granulocytic ehrlichiosis (HGE) is caused by obligate intracellular bacteria in the Ehrlichia phagocytophila group. The disease ranges from subclinical to fatal. We speculated that cell-mediated immunity would be important for recovery from and potentially in the clinical manifestations of HGE; thus, serum tumor necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta), gamma interferon (IFN-gamma), IL-10, and IL-4 concentrations were studied. IFN-gamma (1,035 +/- 235 pg/ml [mean +/- standard error of the mean]) and IL-10 (118 +/- 46 pg/ml) concentrations were elevated in acute-phase sera versus convalescent sera and normal subjects (P