Acute appendicitis; myalgias; fever; This is a literature report for the following literature source(s): "Acute appendicitis following the COVID-19 vaccine", Journal of Surgical Case Reports, 2022. A 69-year-old female patient received BNT162b2 (BNT162B2), as dose 3 (booster), single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Covid-19 vaccine (DOSE 1, MANUFACTURER UNKNOWN), for COVID-19 immunization; Covid-19 vaccine (DOSE 2, MANUFACTURER UNKNOWN), for COVID-19 immunization. The following information was reported: APPENDICITIS (hospitalization, medically significant), 24 hrs. after the suspect product(s) administration, outcome "recovered", described as "Acute appendicitis"; MYALGIA (non-serious), 12 hrs. after the suspect product(s) administration, outcome "recovered", described as "myalgias"; PYREXIA (non-serious), 12 hrs. after the suspect product(s) administration, outcome "recovered", described as "fever". The patient was hospitalized for appendicitis (hospitalization duration: 6 day(s)). The event "acute appendicitis" required emergency room visit. The patient underwent the following laboratory tests and procedures: Blood creatinine: 1.17 mg/dl, notes: elevated; Blood pressure measurement: 96/61 mmHg; Blood urea: 21 mg/dl; Body temperature: 36.7 Centigrade; Cardiac monitoring: normal; Computerised tomogram: perforated acute appendicitis with appendicolith, notes: visualized at the base of the appendix with associated mesenteric fat stranding, multiloculate free fluid and trace-free air; Electrocardiogram: normal; Glomerular filtration rate: 48, notes: units: ml/min/1.73 m2; Haematocrit: 34.8 %, notes: decreased; Haemoglobin: 11.5 g/dl, notes: decreased; Heart rate: 107, notes: units: beats/min; complete review of systems: negative for signs or, notes: Symptoms of gastrointestinal illness in the weeks leading up to this event; notable for RLQ, notes: abdominal pain ongoing for the last several days; Neutrophil count: 7.6 x10 9/l, notes: increased; Oxygen saturation: 93 %, notes: on room air; physical exam: RLQ pain with rebound tenderness, notes: The remaining physical examination was within normal limits, including normal cardiac and respiratory exam and normal electrocardiogram; Pulmonary physical examination: normal; Red blood cell count: 3.73 x10 12/l, notes: decreased; Respiratory rate: 18; SARS-CoV-2 test: negative. Therapeutic measures were taken as a result of appendicitis. Follow-up attempts are completed. No further information is expected. Sender's Comments: Based on limited information in the case, a possible causal association between the reported event Appendicitis and the suspect drug cannot be excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to RAs, Ethics Committees, and Investigators, as appropriate.