Citation: JMM Case Reports. 3(4):e005049, 2016 Aug.Journal: JMM case reports.Published: 2016ISSN: 2053-3721.Full author list: Ghidey FY; Igbinosa O; Mills K; Lai L; Woods C; Ruiz ME; Fishbein D; Sampath R; Lowery R; Wortmann G.UI/PMID: 28348772.Subject(s): PubMed-not-MEDLINE -- Not indexedInstitution(s): MedStar Washington Hospital CenterDepartment(s): Medicine/Infectious DiseasesActivity type: Journal Article.Medline article type(s): Journal ArticleOnline resources: Click here to access onlineDigital Object Identifier: https://dx.doi.org/10.1099/jmmcr.0.005049 (Click here)Abbreviated citation: JMM Case Rep. 3(4):e005049, 2016 Aug.Abstract: INTRODUCTION: Prior studies (predominantly from Europe) have demonstrated blood culture-negative endocarditis due to Bartonella. Our objective was to describe three cases of Bartonella quintana endocarditis identified within one year at a large hospital in Washington, DC, USA.Abstract: CASE PRESENTATION: We constructed a descriptive case series from a retrospective review of medical records from April to December 2013 at an 800-bed urban hospital. All three patients (ages: 52, 55 and 57 years) were undomiciled/homeless men with a history of alcoholism. Although they had negative blood cultures, echocardiography demonstrated aortic/mitral valve perforation and regurgitation in one patient, aortic/mitral valve vegetation with mitral regurgitation in the second patient, and aortic valve vegetation with regurgitation in the third patient. The patients had positive Bartonella quintana serum immunoglobulin G (IgG) with negative immunoglobulin M (IgM). PCR on DNA extracted from cardiac valves was positive for Bartonella, and DNA sequencing of PCR amplicons identified Bartonella quintana. Patients received treatment with doxycycline/rifampin or doxycycline/gentamicin.Abstract: CONCLUSION: Clinicians should consider Bartonella endocarditis as a differential diagnosis in patients who fit elements of the Duke Criteria, as well as having a history of homelessness and alcoholism.