The sexual dimorphism of anticardiolipin autoantibodies in acute Q fever patients.

OBJECTIVES

Q fever is a zoonotic disease caused by Coxiella burnetii which affects men more than women (sex ratio men/women: 2.2). Acute Q fever complications are associated with elevation of anticardiolipin (aCL) antibodies. Here, we investigate the sexual dimorphism of aCL antibodies during acute C. burnetii infection.

METHODS

IgG aCL antibodies were evaluated at the time of Q fever serological diagnosis with enzyme-linked immunosorbent assay. Results were analysed according to sex.

RESULTS

Among the 1323 patients with Q fever tested for aCL, 1013 had acute Q fever (692 men/321 women) and 310 had persistent focalized infection (226 men/84 women). In cases of acute Q fever, men presented a significantly higher proportion of positive aCL antibodies (351/692, 50.7%) than women (113/321, 35.2%) (p <0.05). In addition, men had significantly higher aCL antibodies levels than women (p <0.001).

CONCLUSIONS

We highlight a relationship between sex and markers of autoimmunity during Q fever. Further investigations are necessary to better understand the mechanisms of this sexual dimorphism.