The etiology and pathophysiology of idiopathic recurrent acute pericarditis (IRAP) remain controversial and may involve both an infectious cause (usually viral or bacterial) as a trigger or an autoimmune and autoinflammatory cause in susceptible patients. IRAP is a rare disease of suspected immune-mediated pathogenesis. It represents a diagnosis of exclusion. At first it is necessary to rule out infectious and noninfectious causes of pericardial inflammation, including systemic autoimmune and immune-related disorders, because pericarditis may precede diagnosis of these disorders.  IRAP diagnosis is often made after a long follow-up. A minority of IRAP patients (6%) carry a mutation in the TNFRSF1A gene, encoding the receptor for tumor necrosis factor-alfa.

Partially I found the answer to my question in the article Treatment of Acute and Recurrent Idiopathic Pericarditis.

One or more recurrences arise in 15% to 30% of patients after an initial episode of acute pericarditis. These attacks can repeat over extended periods of time and may lead to substantial disability. A first recurrence typically presents within 18 months, and findings are similar to the initial episode, including pleuritic chest pain, diffuse ST-segment elevations, a pericardial friction rub, and elevated serum markers of inflammation.

https://doi.org/10.1161/CIRCULATIONAHA.111.066365

Last data published 

1.In the United States and Western Europe, most (80-90%) episodes of pericarditis are idiopathic and presumed to be post-viral. In the developing world, most cases of pericarditis are attributable to tuberculosis. Other causes of pericarditis include post-cardiac injury syndromes after acute myocardial infarction, percutaneous coronary or electrophysiologic procedures, or after pericardiotomy.

2.After presentation with acute pericarditis, the probability of developing incessant pericarditis or of a recurrence of pericarditis within 18 months is 15-30%. After an initial recurrence of pericarditis, the risk of recurrence increases to 25-50%.

3.The early use of corticosteroids is associated with an increased risk of recurrence; colchicine therapy is associated with reduced risk of recurrence, and has become a mainstay of treatment. Patient-specific factors associated with increased risk of recurrence include incomplete response to nonsteroidal anti-inflammatory treatment and persistently elevated C-reactive protein.

4.Recurrent attacks of pericarditis may occur because of inability to clear the presumed viral infection with increased viral replication, or due to an autoimmune response caused by molecular mimicry. Recent investigations suggest that innate immunity and its effector mechanisms may be responsible for recurrent idiopathic pericarditis.

5.Novel treatments for refractory pericarditis include azathioprine, human intravenous immunoglobulin, and anakinra (an interleukin-1 receptor antagonist). Once medical therapy has failed, pericardiectomy can be rarely considered to treat refractory pain associated with recurrent pericarditis.

https://www.nature.com/articles/srep13692