Criteria for cure of Q fever in a patient with vascular infection:
(1) antibiotic therapy for >= 3 years
(2) titer of IgG antibody to Phase I antigen < 1:800 (microimmunofluorescence assay)
(3) clinical examination unremarkable (asymptomatic) during followup
Both endocarditis and chronic vascular infections require prolonged therapy, sometimes indefinitely. Other forms of chronic Q fever are treated for 1.5 to 3 years.
Acute Q fever requires therapy of 14-21 days, but may be extended to 1 year if the patient has valvular heart disease.
Maurin and Raoult monitor patients with endocarditis after discontinuation of antibiotic therapy with:
(1) serologic testing monthly for the first 6 months, then every 6 months for 2 years, then annually
(2) echocardiography every 6 months for the first 2 years
