Q Fever Endocarditis

Abstract

Q fever endocarditis is described in a man aged 48 years, known to have had a rheumatic fever-like illness in 1960. He had evidence of aortic valve disease when seen with mumps infection in 1963. He was again seen in 1966 with suspected subacute bacterial endocarditis, but later, Q fever infection was shown to be present by serological tests. He survived for just over one year from the presumed onset of Q fever, in spite of prolonged intensive antibiotic therapy. Necropsy examination showed chronic congestive cardiac failure with pleural and pericardial effusions, and calcific aortic stenosis with tiny vegetations along the edges of the cusps. Rickettsia burneti was isolated only from the damaged aortic valve, and histology revealed colonies of cocco-bacillary bodies between the collagen bundles. Immuno-fluorescence studies suggested that the rickettsiae were heavily coated with 7S gamma globulin (presumably the patient's own specific antibody). It is important to consider Q fever endocarditis in all cases presenting as bacterial endocarditis.