Ehrlichiosis

Introduction. 

Ehrlichiosis is caused by the intracellular parasite Ehrlichia (4 species). It is a disease of animals and humans, with an animals reservoir (zoonosis). Transmission occurs through vecotrs (ticks) or ingesting raw fish infested with Ehrlichia. 

Summary

• Cause: Ehrlichia spp.
• Microscopy: Gram-negative baciili, tiny, intracellular (WBCs)
• Transmission: Ticks
• Symptoms: high fever, headache, malaise, myalgia, leukopenia, rash in < 20%
• Complications: mortality of 5%, mostly in immunocompromised & elderly
• Pathogenesis: Intracellular replication in monocytes and granulocytes kills WBCs
• Treatment: Doxycycline