Abstract: The patient, a 43-year-old man, had paroxysmal headache three months ago, and he had complained the left occipital sharp pain, which could be alleviated by itself, with alalia and the right side of the upper limb numbness. Head computed tomography (CT) revealed a left temporal lobe intraparenchymal hemorrhage with the left side of the subarachnoid hemorrhage in small quantities. Digital subtraction angiography (DSA) revealed a suspicious aneurysm on the left internal carotid artery siphon. He had intermittent fever 1 month ago, with maximum body temperature 39 ℃. He suffered headache again 20 days ago, with pain nature, duration and the way of easing up similar to the earlier onset. General examination demonstrated 2/6 grade blowing systolic murmurs at apex area. Neurological examination revealed that Babinski’s sign was positive on the right side. Echocardiographic found an anterior mitral valve ve-getation on the 4th day in hospital. So his clinical diagnosis was infective endocarditis with cerebral embolism. He received vancomycin treatment immediately. His three blood cultures remained negative in hospital. His blood specimens were sent to Chinese Center for Disease Control and Prevention, indirect immunofluorescence method (IFA) IgG antibody detection revealed that the Bartonella henselae IgG antibody was positive. Therefore the clinical diagnosis was Bartonella endocarditis complicated with subarachnoid hemorrhage and cerebral embolism. Bartonella, an intracellular fastidious, gram-negative bacilli, was first documented as a cause of endocarditis in 1993 and since then has been increasingly recognized as an important etiology of infective culture-negative endocarditis. In cases of documented Bartonella endocarditis, the Infectious Diseases Society of America (IDSA) guidelines recommended 2 weeks of gentamicin plus 6 weeks of doxycycline treatment, to achieve a higher cure rate.

Key words: Subarachnoid hemorrhage, Endocarditis, Bartonella infections