A forgotten cause of chest pain in the United States: a case report on acute rheumatic fever.

backgroundAcute rheumatic fever (ARF) is an acute, immune-mediated process that occurs following an untreated Group A Streptococcus (GAS) infection that can result in complications, such as valvular heart disease, myocarditis and arrhythmias. ARF is now rare in the United States which can make it difficult recognize. The standard for diagnosing ARF remains the revised Jones criteria, including serologic evidence of GAS infection. Given it is encountered so infrequently in the United States, clinicians may face uncertainty when interpreting serologic studies and pursuing cardiac imaging in suspected cases. CASE PRESENTATION: We describe a case of a young white man previously diagnosed with recurrent pericarditis who presented to Tufts Medical Center with chest pain and dyspnea. Around the time of presentation, the patient had tested positive for SARS-CoV-2 with concurrent pharyngitis with white tonsillar exudates. Initial workup was notable for elevated troponin T felt to be out of proportion to pericarditis and changes consistent with myocarditis on cardiac MRI. There were no valvular abnormalities detected on echocardiogram or cardiac MRI. It was later revealed that the patient had been experiencing migratory arthralgias, prompting the measurement of antistreptolysin O (ASO) and antideoxyribonuclease B (ADB), which were both elevated. In combination with serologic evidence of a prior GAS infection, a diagnosis of acute rheumatic fever was made as he satisfied one major (myocarditis) and two minor revised Jones criteria (polyarthralgia and elevated CRP). Though COVID-19 myocarditis was considered as the etiology of his presentation, the recurrent nature of his myopericarditis, multiple prior GAS pharyngitis infections, and elevation in GAS serologic markers favor the diagnosis of ARF.

conclusionsOur case report demonstrates the importance of considering ARF, despite its rarity in the United States. As subacute myocarditis can go undiagnosed by echocardiography, we demonstrate that cardiac MRI is an important tool in establishing a diagnosis of myocarditis that is otherwise inconclusive. The serologic markers ASO and ADB should be used in combination to confirm a preceding GAS infection, given their variability from individual to individual.