Immunoglobulin G anticardiolipin antibodies and progression to Q fever endocarditis.

Abstract

BACKGROUND:

Immunoglobulin G (IgG) anticardiolipin (aCL) antibodies are associated with valvulopathy and endocarditis in patients with lupus and other diseases. During acute Q fever, high IgG aCL prevalence has been reported, but the clinical significance remains unknown.

METHODS:

To test if increased IgG aCL at acute Q fever diagnosis is associated with an increased risk of progression to endocarditis, all patients diagnosed in the French National Referral Center for Q fever from January 2007 to December 2011 were included and followed regularly until January 2013 in a 5-year prospective cohort study. Q fever endocarditis was defined according to recently updated criteria.

RESULTS:

Seventy-two patients were followed for a median time of 31 months (interquartile range, 18-47 months). Of these, 13 patients with valvulopathy without antibiotic prophylaxis progressed to endocarditis. IgG aCL levels were highly prevalent (57%) and significantly higher in the presence of a valvulopathy (P = .005). Using Cox regression analysis, highly increased levels of IgG aCL (adjusted hazard ratio [AHR], 12.95; 95% confidence interval, 2.85-58.95; P = .001) and high levels of phase II immunoglobulin M (IgM; AHR, 6.59; 95% CI, 1.37-31.62; P = .018) were the only independent predictors of progression to endocarditis.

CONCLUSIONS:

Rapid progression from acute Q fever to endocarditis is associated with high levels of IgG aCL and high levels of phase II IgM, findings that should be critical in the prevention of endocarditis.

• Authors: Matthieu Million, Gaëlle Walter, Nathalie Bardin, Laurence Camoin, Roch Giorgi, Pierre Bongrand, Frédérique Gouriet, Jean-Paul Casalta, Franck Thuny, Gilbert Habib, Didier Raoult
• Journal: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America (Clin Infect Dis) Vol. 57 Issue 1 Pg. 57-64 (Jul 2013) ISSN: 1537-6591 [Electronic] United States
• PMID: 23532474 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Anticardiolipin
• Immunoglobulin G
• Immunoglobulin M

Topics

• Adult
• Aged
• Antibodies, Anticardiolipin (blood)
• Endocarditis (diagnosis, immunology, pathology)
• Female
• Follow-Up Studies
• Humans
• Immunoglobulin G (blood)
• Immunoglobulin M (blood)
• Male
• Middle Aged
• Prognosis
• Q Fever (complications, immunology, pathology)