Rarely, a spotted rash may appear about one week after onset of the illness, and, unlike that of Rocky Moutain spotted fever, does not usually involve the palms and soles. Some research has indicated that, since the Ehrlichia organisms invade the white blood cells, the body's immune system is adversely affected. The body's ability to fight other infections is reduced, allowing opportunistic infection such as fungal pneumonia to occur. In severe cases other complications may arise, including respiratory problems, blood and kidney abnormalities, meningitis and other central nervous system complications. Ehrlichiosis should be considered in any febrile patient who has been exposed to ticks during the previous three weeks, particularly if low blood counts are present.
Prompt treatment is important.
However, antibodies to E. chaffeensis did not develop in six PCR-confirmed patients during convalescence, suggesting that serologic testing may be less sensitive than generally assumed. For HGE, serologic confirmation requires a four-fold increase in antibody titer to E. equi . In HGE, Ehrlichiae occasionally form clumps called morulae within the leukocytes, which may be seen in a blood smear. Search for morulae of E. chaffeensis in leukocytes is unrewarding. Since prompt treatment is important, the decision to initiate antibiotic therapy must be based on clinical findings and epidemiologic considerations.