title: "Grey zone" patterns of unexplained endocarditis: still a challenge for clinical decision making.
abstract: The authors report two cases of unexplained active inflammatory endocarditis with totally different clinical presentations. The patients had undergone previous mitral repair surgery and were referred for multiple soft mobile masses on the mitral ring without clinical or laboratory signs of endocarditis. Serologic screening and blood culture results were negative, including those for specific fastidious bacteria, as well as immunologic tests to rule out "nonbacterial thrombotic endocarditis." Before new surgery, both patients were treated with long-term antibiotic and anticoagulant therapy, with no significant changes in clinical setting and echocardiographic patterns. In neither case was it possible to characterize a specific microorganism: the intraoperative findings were highly evocative of active endocarditis with a macroscopic infiltration of the mitral ring, and culture results from surgical material and valvular tissue were negative.
authors.affiliation: Cardiovascular and Thoracic Department, San Raffaele University Hospital, Milan, Italy. antonio.grimaldi@hsr.it
authors.forename: Antonio
authors.initials: A
authors.lastname: Grimaldi
authors.forename: Maurizio
authors.initials: M
authors.lastname: Taramasso
authors.forename: Francesco
authors.initials: F
authors.lastname: Maisano
authors.forename: Giovanni
authors.initials: G
authors.lastname: La Canna
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Pala
authors.forename: Stefano
authors.initials: S
authors.lastname: Benussi
authors.forename: Giorgio
authors.initials: G
authors.lastname: Viganò
authors.forename: Ottavio
authors.initials: O
authors.lastname: Alfieri
mesh_terms: D001424:Bacterial Infections / Q000000981:diagnostic imaging* / Q000382:microbiology*; D003937:Diagnosis, Differential; D004696:Endocarditis / Q000000981:diagnostic imaging* / Q000382:microbiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography