Q fever endocarditis: the Mayo Clinic experience.

Area of Science:

• Infectious Diseases
• Cardiology
• Medical Case Studies

Background:

• Q fever endocarditis is infrequently reported in North America.
• The Centers for Disease Control and Prevention (CDC) does not specifically track endocarditis as a Q fever syndrome.
• Limited literature exists on Q fever endocarditis.

Purpose of the Study:

• To describe the Mayo Clinic's experience with Q fever endocarditis.
• To highlight the clinical characteristics and management of this rare condition.

Main Methods:

• Retrospective review of patients with elevated Q fever IgG serology from December 1980 to December 2005.
• Identification of cases meeting diagnostic criteria for endocarditis.

Main Results:

• Seven patients were diagnosed with Q fever endocarditis.
• All patients presented with fever and pre-existing valvular disease.
• Valvular vegetations were uncommon (3/7 patients).
• Six patients required valve surgery, with two needing multiple procedures.
• Follow-up ranged from 1 to 17 years.

Conclusions:

• Q fever endocarditis is a rare, underreported disease in the US.
• It commonly affects abnormal native or prosthetic valves, often with minimal vegetations.
• Relapses and surgical interventions are frequent, increasing morbidity and costs.
• Increased awareness is needed for culture-negative endocarditis or unexplained echocardiographic findings.
• Timely diagnosis and targeted therapy can potentially decrease repeat surgeries.