A case report of relapsing fever.

Relapsing fever is an acute febrile illness caused by spirochetes of the genus Borrelia. The high fevers of presenting patients spontaneously abate and then recur. Here we report a 50-year-old woman having relapsing fever associated with thrombocytopenia. Giemsa staining of peripheral blood smear revealed spiral organisms morphologically resembling Borrelia. A rare case of relapsing fever which was successfully treated with doxycycline is discussed.