From Streptococcal Pharyngitis/Tonsillitis to Myocarditis: A Systematic Review.

(1) Background: Myocarditis following group A streptococcal pharyngitis and tonsillitis is a relatively rare medical condition. The aim of this systematic review was to identify specific ECG changes, laboratory parameters and signs, and symptoms associated with this disease. (2) Methods: A systematic literature review was performed in concordance with the current PRISMA guidelines, including the databases PubMed/MEDLINE, Web of Science, CDSR, CENTRAL, CCAs, EBM Reviews, and LILACS. Articles were included if they covered myocarditis after streptococcal pharyngitis/tonsillitis in humans. Exclusion criteria were rheumatic, autoimmune, or toxic myocarditis. (3) Results: Patients that developed myocarditis after group A streptococcal throat infection frequently presented with chest pain, elevated cardiac markers, and ST-segment elevations, making it a condition that shows more similarities to acute coronary syndrome than viral myocarditis. (4) Conclusions: Myocarditis after streptococcal pharyngitis and/or tonsillitis is a rather infrequently described disease; however, it is necessary to consider this condition when investigating streptococcal sore throat because it can be associated with severe adverse events for the individual patient.