Diagnosis of tick-borne relapsing fever by the quantitative buffy coat fluorescence method

The quantitative buffy coat (QBC) parasite detection method is a sensitive and specific tool for the diagnosis of malaria parasites. It is also useful for the diagnoses of other hemoparasites, including Trypanosoma, Babesia, and Leptospira. We report a case of relapsing fever diagnosed by this techn ique in a short-term traveler from Senegal. The diagnosis was confirmed by the standard Giemsa hemoscopy and by the identification of significant tite rs of antibodies to Borrelia spp. of tick-borne relapsing fevers by specifi c immunofluorescence and Western blot tests. The QBC technique seems to be useful in the diagnosis of tick-borne relapsing fever in blood samples and should be included in the management of fever in the traveler returning fro m tropical regions.