Rôle de Bartonella quintana dans les endocardites infectieuses en Algérie

In Algeria, retrospective studies showed Streptococci and Staphylococci were the leading causes of infective endocarditis. A high percentage of blood culture negative cases was reported even without previous antimicrobial therapy, however, no study has evaluated fastidious agents as possible etiologies of infective endocarditis. In our study, we collected samples from 110 patients with suspected cases of endocarditis. Among them, there were 62 blood culture negative cases (56,3 %) witch we tested retrospectively in France by serologic or molecular methods or both. By using these tools, the etiology of 28 cases was clarified. 18 of those were due to zoonoses or arthropodborne bacterial diseases, which represent nearly one quarter of the performed diagnoses (25 %) Of these, Bartonella quintana, was identified as the causative agent of 14 cases (13% of al cases). This bacteria accounts for only 1 to 3 % of the etiologies of infective endocarditis in Europe and in the USA and is often related to homeless people and alcoholic. Body louse seems to be the vector for the bacteria. In our series, Bartonella quintana endocarditis cases are in majority poor and live in promiscuity, but are neither SDF, nor alcoholics. Indeed, Rickettsia prowazeki, the agent of epidemic typhus, is also transmitted by body lice and those who live in extreme poverty are the persons most often infested. The recent report of typhus cases in Algeria confirms that poor socioeconomic conditions exist in this country and can explain the emergence of Bartonella quintana as one of the common causative agent of infective endocarditis in our series (19,5 % of agents identified). Our study un- derlines the need to perform serologic and molecular tools to determine the etiology of blood culture-negative endocarditis in Algeria.