Acute Pericarditis: Understanding the Primary Causes

Acute pericarditis is a condition characterized by inflammation of the pericardium, the sac-like membrane surrounding the heart. It can be triggered by a variety of underlying causes, including infections, metabolic disorders, radiation exposure, trauma, medications, and malignancies. Identifying the exact cause is crucial for effective treatment. Regardless of the origin, it is highly recommended to seek medical attention at a reputable healthcare facility as soon as symptoms appear.

Infectious Causes

One of the most common causes of acute pericarditis is infection. Bacterial agents such as streptococcus, pneumococcus, and staphylococcus are frequently implicated. Viruses, fungi, and parasites can also lead to inflammation of the pericardium. Infections may reach the pericardium through multiple pathways. For example, in cases of pneumonia or empyema, bacteria may spread directly from the lungs or pleura into the pericardial space, either through lymphatic channels or by direct extension. Additionally, subdiaphragmatic or liver abscesses can rupture through the diaphragm and infect the pericardium, triggering an inflammatory response.

Metabolic and Autoimmune Triggers

Acute pericarditis can also result from systemic diseases affecting other organs or body systems. Conditions such as rheumatic fever, systemic lupus erythematosus (SLE), hypothyroidism, and HIV/AIDS are known to contribute to pericardial inflammation. These disorders often involve immune-mediated mechanisms that lead to fluid accumulation and irritation around the heart.

Radiation-Induced Pericarditis

Radiation therapy, especially when directed at the chest area for cancers such as breast cancer or lymphoma, can cause delayed inflammation of the pericardium. This is typically due to long-term tissue damage and scarring caused by radiation exposure. Symptoms may appear months or even years after treatment has concluded.

Trauma and Physical Injury

Physical trauma to the chest, such as blunt force injury or penetrating wounds, can cause bleeding into the pericardial sac. This condition, known as hemopericardium, can provoke an acute inflammatory response. Medical procedures involving catheters or pacemaker insertion may also inadvertently cause pericardial damage, leading to pericarditis.

Drug-Induced Pericarditis

Certain medications have been associated with drug-induced pericarditis due to their potential cardiotoxic effects. Examples include hydralazine, procainamide, phenytoin, isoniazid, and methimazole. These drugs may trigger immune reactions or direct toxicity to cardiac tissues, resulting in pericardial inflammation.

Malignancy-Related Pericarditis

Several types of cancer, including lung cancer, breast cancer, esophageal cancer, and lymphomas, can metastasize or directly invade the pericardium. This infiltration leads to irritation and inflammation, often resulting in pericardial effusion and acute pericarditis. In some cases, cancer patients may experience recurrent or refractory pericarditis, requiring specialized management.