FEVER, NEGATIVE BLOOD CULTURE AND ABSENT RESPONSE TO ANTIBIOTICS IN APATIENT AFTER A 2ND AORTIC-VALVE REPLACEMENT

History and clinical findings: A 53-year-old patient had a prosthetic valve (St. jude Medical 25) 9 years ago because of a Staphylococcus au reus endocarditis with severe aortic regurgitation. An initially mild, progressively more severe, aortic regurgitation then developed as a r esult of an empty paravalvar abscess cavity, requiring another valve r eplacement. Fever started on the 3rd postoperative day and persisted d espite combined treatment with p-lactam antibiotics and aminoglycoside . Investigations: At first no infectious focus could be identified rad iologically or by echocardiography. But transoesophageal echocardiogra phy revealed vegetations in the old abscess cavity. Several blood cult ures were negative, while serological tests gave markedly raised antib ody titers against Coxiella burnetii. Diagnosis, treatment and course: Assuming Coxiella burnetii endocarditis the patient was given doxycyc line, 2 x 100 mg daily and cotrimoxazole, 1 x 960 mg daily. The fever subsided and the vegetations had disappeared after four weeks. Because of the high risk of recurrence the antibiotic treatment was to be con tinued for two years. Conclusion: Coxiella burnetii should be consider ed as a possible cause of fever of unknown origin, especially in patie nts with existing or operated cardiac valvar defects, when endocarditi c vegetations have been demonstrated and several blood cultures have b een negative.