Antiphospholipid Antibody Syndrome With Valvular Vegetations in Acute Q Fever.
BACKGROUND Coxiella burnetii endocarditis is considered to be a late complication of Q fever in patients with preexisting valvular heart disease (VHD) We observed a large transient aortic vegetation in a patient with acute Q fever and high levels of IgG anticardiolipin antibodies (IgG aCL) Therefore, we sought to determine how commonly acute Q fever could cause valvular vegetations associated with antiphospholipid antibody syndrome, which would be a new clinical entity. METHODS We performed a consecutive case series between January 2007 and April 2014 at the French National Referral Center for Q fever. Age, sex, history of VHD, immunosuppression, and IgG aCL assessed by enzyme linked immunosorbent assay were tested as potential predictors. RESULTS Of the 759 patients with acute Q fever and available echocardiographic results, 9 (1.2% were considered to have acute Q fever endocarditis, none of whom had a previously known VHD. After multiple adjustment, very high IgG aCL levels >100 immunoglobulin G type phospholipid units; relative risk [RR] 24.9 [95% confidence interval {CI} 4.5 140.2] P .002) and immunosuppression (RR, 10.1 [95% CI, 3.0 32.4] P .002) were independently associated with acute Q fever endocarditis. CONCLUSIONS Antiphospholipid antibody syndrome with valvular vegetations in acute Q fever is a new clinical entity. This would suggest the value of systematically testing for C. burnetii in antiphospholipid associated cardiac valve disease, and performing early echocardiography and antiphospholipid dosages in patients with acute Q fever.
Clinical infectious diseases an official publication of the Infectious Diseases Society of America