Background: African tick-bite fever is caused by R. africae. All cases reported to date in France have occurred among patients who came from southern Africa, the endemic zone. We report the first case, to our knowledge, of a patient infected in France.
Case report: A 69-year-old white man who had never left France developed fever and 3 "black spots" on the legs with lymphangitis and enlarged nodes. The clinically suspected diagnosis was confirmed by positive serology reactions to R. africae. As cross immunity with R. conorii can occur, the diagnosis was further confirmed by western blot for R. africae and by the persistence of the reaction after adsorption of the R. conorii serum.
Discussion: African tick-bite fever was identified as a clinical entity different from Mediterranean spotted fever by Kelly in 1992 who demonstrated the causal role of R. africae. The typical clinical presentation associates fever, several black spots, lymphangitis and multiple node enlargement. The serological diagnosis is difficult owing to cross immunity with R. conorii. Western blot and polymerase chain reaction are required for definitive diagnosis. In our case, the infection was probably due to a R. africae imported into France in the luggage of the patient's daughter who had spent 3 months in Zimbabwe.