African Tick Bite Fever

Physicians may encounter unfamiliar diseases as a result of international travel. Fever with rash is an important sign that usually represents initial manifestation of infectious disorders. A 62-year-old Taiwanese woman presented with multiple eschars, a papulovesicular rash, and fever 5 days after returning from South Africa. A biopsy specimen of an eschar had wedge-shaped tissue necrosis, hemorrhage, necrotizing vasculitis of the small venules and arterioles, and a dense perivascular lymphocytic infiltrate in the dermis. Serologically, there was cross reaction with both Rickettsia conorii and R. rickettsii. DNA sequencing demonstrated R. africae, confirming the diagnosis of African tick bite fever. The patient responded well to minocycline. Recognition of the symptoms and signs, and diagnostic tools for different types of rickettsiosis are essential for correct diagnosis and treatment.