Listeria myopericarditis associated with right atrial mural thrombus: a case report

Pericarditis is a common cardiology presentation, most often due to a viral or idiopathic cause. Listeria as a cause of pericarditis is rare. Listeria is an infection that is readily treatable with antibiotics following accurate identification. Without adequate treatment, Listeria infection has a high mortality rate.

In this case, a fit and well 59-year-old man complained of headaches and fever to the emergency department (ED). He was provisionally diagnosed with giant cell arteritis (GCA) and commenced on management pathways for GCA. He represented to the ED with chest pain and electrocardiogram (ECG) changes suggestive of a clinical presentation of pericarditis. He received treatment for idiopathic pericarditis with no clinical resolution. Cardiac magnetic resonance imaging (MRI) showed myopericardial inflammation associated with a right atrial mural thrombus. After 2 weeks of poor treatment response, peripheral blood cultures grew Listeria monocytogenes and the patient responded well to antibiotic treatment. Repeat cardiac MRI after an extended course of antibiotics showed resolution of MRI signs.

This is a case of Listeria myopericarditis. Physicians should consider rarer causes of myopericarditis in treatment resistance cases. Cardiac MRI has utility in atypical or treatment resistant patients to assess myopericardial inflammation and response to treatment.