Infectious Pericarditis in Children: Understanding the Causes

Infectious pericarditis in children is most commonly caused by viral infections. Clinically, both acute idiopathic and non-idiopathic pericarditis are often linked to viral infections or post-infectious immune and allergic reactions. When the condition is accompanied by widespread subepicardial myocardial necrosis, it may lead to acute perimyocarditis. Additionally, other forms such as tuberculous or purulent pericarditis can also occur, depending on the underlying infection.

Common and Rare Etiologies of Childhood Pericarditis

While viral agents are the primary cause, other less common infectious agents can also trigger pericarditis in children. These include rickettsiae, chlamydiae, mycoplasma, and protozoal infections. Identifying the exact pathogen is crucial for targeted treatment and better clinical outcomes.

Classification Based on Pathological Features

Pericarditis can be classified into two main pathological types: fibrinous and effusive. In fibrinous pericarditis, there is minimal fluid accumulation and usually no significant hemodynamic impact. However, in effusive pericarditis, the accumulation of fluid in the pericardial space can impair ventricular expansion and filling, leading to obstructed venous return, elevated venous pressure, and a subsequent decrease in cardiac output.

Hemodynamic Implications of Pericardial Effusion

The severity of hemodynamic changes in effusive pericarditis depends on several factors, including the volume of fluid, the rate at which it accumulates, and its physical properties, such as viscosity. Rapid accumulation of even a small amount of fluid can significantly compromise cardiac function, while slower accumulation may allow for compensatory mechanisms to maintain stable circulation.