Relapsing or recurrent pericarditis is probably the most troublesome complication of acute pericarditis, and represents one of the greatest therapeutic challenges among the disorders of the pericardium.

DEFINITIONS

The term relapsing pericarditis includes two clinical types, the incessant type and the intermittent type of recurrent pericarditis. The term incessant applies to those patients in which discontinuation or attempts to wean from anti-inflammatory treatment nearly always ensures a relapse in a period of less than six weeks.¹ This situation can be seen after discontinuation of the usual anti-inflammatory drugs (aspirin, indomethacin, or ibuprofen) but is particularly frequent and worrying in patients on steroids. Some of these patients may be said to be “steroid hooked” and, in fact, these patients can show a threshold level of prednisone treatment (usually between 10–20 mg) below which relapse is probable. The term “intermittent” refers to those patients with symptom-free intervals conventionally longer than six weeks without treatment.

FREQUENCY

The possibility of recurrences was already recognised in early descriptions of acute pericarditis.² Their frequency in clinical series including more than 40 patients^3–7 varies between 8–80% (average 24%), with no distinction between incessant and intermittent types. In our experience,⁷ one or more recurrences were present in 44 of 221 consecutive patients with acute idiopathic pericarditis.

AETIOLOGY AND AETIOPATHOGENESIS

The most typical form of relapsing pericarditis (table 1) occurs after a first episode of idiopathic benign pericarditis, presumably of viral origin. The viruses most frequently implicated are enterovirus, mainly coxsackie B. Higher concentrations of immunoglobulin IgM antibodies have been found in patients with relapses, which can express a persistent viral antigenic stimulation due to persistent viral infection or new exposure to viral illness. Autoimmune responses can certainly play a role in the pathogenesis of recurrent idiopathic or postviral pericarditis.¹ Inadequate anti-inflammatory treatment of the index attack can …