Human granulocytic ehrlichiosis in the United States

Human granulocytic ehrlichiosis (HGE) is a tick-borne, acute, nonspecific febrile illness that was first described in 1994; 142 cases from 10 states had been diagnosed by April 1996. Characteristic inclusions (morulae) have been observed in the cytoplasm of neutrophils in 80% of patients from the upper Midwest. Polymerase chain reaction of acute-phase blood or a 4-fold or greater convalescent antibody seroconversion confirms the diagnosis. Tetracycline or doxycycline provide effective treatment and should be administered for 2 weeks to ensure sufficient treatment for HGE as well as possible Lyme borreliosis coinfection.