Antiphospholipid syndrome masquerading as a case of infective endocarditis

Area of Science:

• Cardiology
• Rheumatology
• Neurology

Background:

• Antiphospholipid syndrome (APS) is an autoimmune disorder associated with an increased risk of thrombosis.
• Infective endocarditis (IE) is an infection of the heart valves, often presenting with embolic phenomena.

Observation:

• A 54-year-old woman presented with loss of consciousness and dysphasia, suggestive of embolic stroke.
• Cardiac imaging revealed mitral valve vegetation, initially leading to a presumed diagnosis of infective endocarditis.
• Despite empirical antibiotic treatment for IE, the patient's condition worsened.

Findings:

• Blood cultures were negative, prompting further investigation.
• The patient tested positive for antiphospholipid antibodies.
• A final diagnosis of antiphospholipid syndrome complicated by Libman-Sacks endocarditis was established.

Implications:

• This case highlights the importance of considering antiphospholipid syndrome in patients with suspected infective endocarditis and embolic events, especially with negative blood cultures.
• Libman-Sacks endocarditis, a non-infectious valvular manifestation of APS, requires specific management.
• Prompt diagnosis and treatment with anticoagulation and immunosuppressive therapy (e.g., steroids) can lead to significant clinical improvement in APS-related cardiac complications.