Perimyocarditis; body aches; fever; This literature-non-study case was reported in a literature article and describes the occurrence of MYOCARDITIS (Perimyocarditis) in a 22-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.   LITERATURE REFERENCE: Perimyocarditis following frst dose of the mRNA-1273 SARS-CoV-2 (Moderna) vaccine in a healthy young male. BMC Cardiovasc Disord. 2021;21(1):375     The patient's past medical history included COVID-19 (Six months prior patient had a mild case of COVID-19).    On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, the patient experienced MYOCARDITIS (Perimyocarditis) (seriousness criteria hospitalization prolonged and medically significant), MYALGIA (body aches) and PYREXIA (fever). The patient was treated with ASPIRIN [ACETYLSALICYLIC ACID] for Chest pain and Pericardial effusion, at a dose of 650 milligram three times a day; COLCHICINE for Chest pain and Pericardial effusion, at a dose of .6 milligram twice a day and METOPROLOL for Myocardial infarction, at an unspecified dose and frequency. At the time of the report, MYOCARDITIS (Perimyocarditis) was resolving and MYALGIA (body aches) and PYREXIA (fever) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, Blood pressure measurement: 97/57 mm hg (abnormal) Blood pressure was 97/57 mm Hg. In 2021, Body temperature: 98.6° fahrenheit (normal) Patient was afebrile with a temperature of 98.6° Fahrenheit (38.6° Celsius). In 2021, Brain natriuretic peptide (Unknown-< 100): 48.0 pg/ml (normal) B-type natriuretic peptide level was 48.0 pg/mL. In 2021, Catheterisation cardiac: normal (normal) Left heart catheterization revealed angiographically normal coronary arteries. Left ventricular end-diastolic pressure was 18 mmHg.. In 2021, Chest X-ray: unremarkable (normal) Chest radiograph was unremarkable with no signs of focal consolidation, pneumothorax, or pleural effusion. In 2021, Drug screen: negative (Negative) Negative. In 2021, Echocardiogram: low-normal (abnormal) echocardiogram revealed low-normal left ventricular ejection fraction (LVEF) of 5055% with mid to apical anterior and anterolateral segments appearing hypokinetic. In 2021, Electrocardiogram: abnormal (abnormal) ECG revealed normal sinus rhythm with diffuse ST elevation. In 2021, HIV test: negative (Negative) Negative. In 2021, Heart rate: 100 beats/min (normal) heart rate 100 beats/min and 7080 beats per minute (normal) heart rate improved to a range of 7080 beats per minute. In 2021, Magnetic resonance imaging heart: abnormal (abnormal) showed a normal LVEF (58 %) with findings of dyssnchrony of the septal wall. Also showed subepicardial late gadolinium enhancement (LGE) involving the lateral wall and inferior segments at the midventricular and apical LV. Mild adjacent pericardial LGE was also noted. These findings were consistent with perimyocarditis. and improved (normal) one month following discharge, a repeat cardiac MRI was performed which showed improved subepicardial and adjacent pericardial delayed enhancement in the mid and distal left ventricle. Also showed resolution of the previously noted dyssnchrony suggestive of improving perimyocarditis.. In 2021, Metabolic function test: unremarkable (normal) complete metabolic panel was unremarkable. In 2021, Oxygen saturation: 99% (normal) oxygen saturation was 99 % on room air. In 2021, Respiratory rate: 16 breaths/min (normal) respiratory rate 16 breaths/min. In 2021, Respiratory viral panel: negative (Negative) Negative. In 2021, SARS-CoV-2 test: negative (Negative) Negative. In 2021, Troponin (3-20): 13,702 ng/l (High) High sensitivity troponin was 13,702 ng/L, normal (normal) troponin downtrended and elevated (High) markedly elevated troponin. In 2021, White blood cell count: 8700/cm3 (normal) white blood cell count was 8700/cm3 with a neutrophilic predominance of 83%.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered MYOCARDITIS (Perimyocarditis), MYALGIA (body aches) and PYREXIA (fever) to be possibly related.    Patient took no medications or over the-counter supplements and denied any significant family history of chronic conditions including cardiovascular disease. Patient also denied any tobacco, alcohol, or recreational drug use.  On physical examination, patient was tachycardic with a regular rhythm. No murmurs, rubs, or gallops were appreciated on auscultation. No jugular venous distension, tenderness to palpation of the chest wall, or lower extremity edema were noted.  Because of patient's pleuritic chest pain shortly after vaccination, author's leading diagnosis was acute pericarditis. However, they also kept life-threatening causes such as acute coronary syndrome in their differential diagnosis.  Patient was discharged with plans to complete a two week course of aspirin, three months of colchicine, and metoprolol.  Patient did not require endomyocardial biopsy during his hospitalization since he remained clinically stable. Was also not started on guideline-directed medical therapy for heart failure since his imaging showed no signs of ventricular dysfunction.  Metoprolol was started to help prevent heart failure, life-threatening arrythmias, and also limit mechanical inflammation'.  Patient was recommended abstinence from strenuous activity to decrease risk of remodeling and sudden death as well.   Given the hypersensitivity myocarditis that the patient suffered following the first dose of the Moderna vaccine and lack of information available at the time, after a patient-centered discussion, he elected to forego the second dose of the vaccine.  Company Comment: Based on the current available information and temporal association between the use of the product, and the start date of the events, a causal relationship cannot be excluded.; Sender's Comments: Based on the current available information and temporal association between the use of the product, and the start date of the events, a causal relationship cannot be excluded.