Acute Non-Rheumatic Myocarditis Following Group G Streptococcal Pharyngitis: A Rare Mimic of Acute Myocardial Ischemia in a Young Adult.

Abstract

Background: Acute myocarditis is a rare but serious inflammatory condition of the myocardium, often triggered by infections or rheumatic heart disease. While group A Streptococcus is commonly associated with bacterial myocarditis, group G Streptococcus is rarely implicated. This case highlights a rare instance of non-rheumatic acute myocarditis also known as Streptococcal pharyngitis acute myocarditis caused by group G Streptococcus in a 19-year-old male without rheumatic fever.

Case report: A previously healthy 19-year-old male presented with chest pain, fever, and sore throat, prompting hospitalization. The diagnosis of acute myocarditis was based on elevated cardiac biomarkers, electrocardiographic abnormalities, and cardiac magnetic resonance imaging, with group G Streptococcus infection confirmed by throat polymerase chain reaction. The patient responded well to antibiotics and anti-inflammatory therapy.

Conclusions: This case highlights group G Streptococcus-induced pharyngitis acute myocarditis, stressing the need for prompt diagnosis and treatment in young adults presenting with recent streptococcal pharyngitis.

Learning points: This case highlights a rare instance of non-rheumatic acute myocarditis also known as Streptococcal pharyngitis acute myocarditis, caused by group G streptococcus in a 19-year-old male without rheumatic fever.Streptococcal pharyngitis acute myocarditis may present with clinical features closely resembling an acute coronary syndrome; hence advance cardiac imaging is essential to confirm myocarditis and rule out true ischemic heart disease.Cardiac magnetic resonance imaging was used to diagnose Streptococcal pharyngitis acute myocarditis which showed subepicardial hyper-enhancement 4 weeks after discharge and resolution of symptoms.Prompt diagnosis was achieved, and the patient was treated with antibiotics and anti-inflammatory therapy in a timely fashion with good response.