Human monocytic ehrlichiosis
Overview
A rare infectious condition caused by infection with a type of bacteria called Ehrlichia (Ehrlichia chaffeensis) which attack monocytes(a type of white blood cell). The infection is transmitted by the Lone Star and American dog tick
Symptoms
* Fever * Headache * Muscle pain * Chills * Anemia
Causes
Ehrlichiosis is caused by Ehrlichia organisms, specifically E. chaffeensis and granulocytic Ehrlichia. Known vectors include the lone star tick (Amblyomma americanum), the American dog tick (Dermacentor variabilis), and deer ticks (Ixodes dammini and Ixodes scapularis).
Diagnosis
Tick exposure is often overlooked. For patients living in high-prevalence areas who spend time outdoors, a high degree of clinical suspicion should be employed.
Treatment
If Ehrlichiosis is suspected, treatment should not be delayed while waiting for a definitive laboratory confirmation, as prompt doxycycline therapy has been associated with improved outcomes. Doxycycline is the treatment of choice. Presentation during early pregnancy can complicate treatment. Rifampin has been used in pregnancy and in patients allergic to doxycycline