Coxiella burnetii (Q fever)
[Clin Infect Dis 2011;52:1431, Lancet Infect Dis 2010;10:527, European Heart J 2009;30:2369-2413, J Antimicrob Chemother 2012;67:269-89.]
Clinical
Associated with previous valve disease, prosthetic valve, or immunosuppression and contact with cattle, sheep, goats, cats, and dogs.
Endocarditis most common manifestation of chronic (> 6 months) infection.
Peripheral manifestations common: splenomegaly, digital clubbing, purpuric rash, hepatomegaly, immune complex glomerulonephritis, pulmonary/pleural emboli.
Treatment success predicted if: IgG titre < 1:200, IgA and IgM titres < 1:50.
Diagnosis
Serology - phase 1 IgG antibody titre > 1:800
Culture, immunohistology and PCR of surgical material.
If possible, at least 3 weeks of therapy should be given prior to valve surgery.
Therapy | Dose | Duration |
---|---|---|
Doxycycline | 100mg PO bid | ≥ 18 months |
+ | ||
Hydroxychloroquine | 200mg PO tid | ≥ 18 months |
Alternative
Therapy | Dose | Duration |
---|---|---|
Doxycycline | 100mg PO bid | 36 months |
+ | ||
[Ciprofloxacin | 750mg PO bid | 36 months |
or | ||
Levofloxacin] | 750mg PO daily | 36 months |