Common Causes of Acute Pericarditis

1. Idiopathic Pericarditis

Idiopathic pericarditis accounts for approximately 80% to 90% of all acute pericarditis cases. In these instances, standard diagnostic procedures often fail to identify a specific cause, hence the term "idiopathic." However, medical experts believe that many of these cases may be linked to viral infections. Despite this assumption, identifying the exact virus involved can be difficult using routine testing methods.

2. Infectious Pericarditis

Infectious pericarditis is typically caused by bacterial, tuberculous, fungal, or other microbial infections. Among these, tuberculous pericarditis is the most prevalent form globally, especially in regions with high tuberculosis rates. Bacterial and purulent types are also common and may arise from direct infection or spread from nearby infected areas of the body.

3. Non-Infectious Pericarditis

Non-infectious causes contribute significantly to acute pericarditis cases. These may include complications following a heart attack, particularly transmural myocardial infarction. Other non-infectious triggers include advanced uremia, certain cancers, chylous or cholesterol-related pericardial effusions, trauma, aortic dissection, and sarcoidosis. These conditions can lead to an acute inflammatory response in the pericardium.

4. Autoimmune or Immune-Mediated Pericarditis

Allergic or immunologic reactions can also lead to pericarditis. Examples include rheumatic pericarditis, vasculitis-related pericarditis, and drug-induced pericarditis. These forms are often associated with systemic autoimmune disorders or adverse reactions to certain medications, which trigger an abnormal immune response affecting the pericardium.