remitting seronegative symmetrical synovitis with pitting oedema; This is a Literature report from BMJ Case Reports, 2021, volume 14(8), DOI: 10.1136/bcr-2021-244479, entitled "Remitting seronegative symmetrical synovitis with pitting oedema following BNT162b2 mRNA COVID-19 vaccination". This reporter reported 2 reports; this is the 1 of 2 reports.  In the present study, authors report the first case of remitting seronegative symmetrical synovitis with pitting oedema (RS3PE) induced by BNT162b2 mRNA COVID-19 vaccination in a patient with no history of rheumatic disease. Healthcare providers need to be aware of this condition induced by COVID-19 vaccine and appropriately treat it. An 80-year- old [race] man presented with a 2-week history of acute onset of bilateral hand swelling and pain, which was worse in the left hand and was associated with paresthesia. The symptoms began 2 days following the second dose of the BNT162b2 mRNA COVID-19 vaccine. The patient's medical history included hypertension, hyperlipidaemia, atrial fibrillation, ischaemic cardiomyopathy, aortic valve stenosis, COPD (Chronic obstructive pulmonary disease), sleep apnoea and without any previous history of any rheumatic disorder. Physical examination revealed symmetrical pitting oedema in the dorsum of both hands and synovitis (Clinical features of the patient bilateral pitting oedema of the dorsum of the hands, worse in the left hand). Laboratory investigations revealed an elevated erythrocyte sedimentation rate of 55 mm/hour (normal less than 20) and C reactive protein level of 120 mg/L (normal less than 5), with negative antinuclear antibodies rheumatoid factor and anticyclic citrullinated peptide antibodies. The patient's laboratory studies results and reference range (RR) were as follow: White cell count: 8.8*9/L (RR, 4-10.0 x 10*9/L); haemoglobin: 13.1 g/L, (RR, 12-16 g/L); platelet: 230 x 109/uL, (RR, 150-350x 109/uL); sedimentation rare: 55 mm/hour, (RR: less than 20 mm/hour); C reactive protein: 120 mg/L, (RR, less than 5 mg/L); Creatinine: 0.9 mg/dL, (RR, 0.6-1.2 mg/dL); alanine aminotransferase: 32 U/L, (RR, 7-55 U/L); aspartate aminotransferase: 27 U/L, (RR, 8-48 U/L); Alkaline phosphatase: 79 U/L, (RR, 45-115 U/L); Hepatitis C antibody: Negative, (RR, Negative); Parvovirus B19 IgM: Negative, (RR, Negative); Parvovirus B19 IgG: Negative, (RR, Negative); Antinuclear antibodies: Negative, (RR, Negative); Rheumatoid factor: 10 IU/mL, (RR, less than 14 IU/mL); Cyclic citrullinated peptide antibodies: 6 U/mL, (RR, less than 20 U/mL). The full blood count, renal and liver function tests were normal. Hepatitis B and C antibodies, parvovirus B19 were negative. The hand radiographs did not show any evidence of erosion or chondrocalcinosis. Chest radiograph was normal. The differential diagnosis included crystal-induced arthritis, such as gout or calcium pyrophosphate deposition disease, but the absence of chondrocalcinosis and the persistent nature of the patient's symptoms. An additional consideration was late-onset rheumatoid arthritis; however, the autoantibodies were negative, and the dorsal hand pitting oedema is not a classic manifestation of rheumatoid arthritis. Given the abrupt onset of symptoms, the puffy oedematous hands and significant response to glucocorticoids, the patient was diagnosed with RS3PE. The patient took paracetamol without symptom relief. He was prescribed prednisolone 15 mg daily and had a remarkable improvement in his symptoms (Clinical features following treatment with low-dose glucocorticoids. Significant improvement was noted with glucocorticoids, with less swelling). In addition, the patient also underwent physical therapy and used topical NSAIDs. Three months following the onset of his symptoms, a trial to wean off prednisolone was unsuccessful, and the patient stills require prednisolone 5 mg daily. The repeated erythrocyte sedimentation was 36 mm/hour (normal less than 20) and C reactive protein level of 3 mg/L (normal less than 5). Authors discussed the option to add a disease modifying antirheumatic drug, such as methotrexate, but the patient was reluctant to take the medication. In authors' case, the patient fulfilled the criteria mentioned above and the kinetics of symptom onset (2 days after the second dose of the vaccine) strongly suggests that the RS3PE was triggered by the vaccination. Patient' s perspective: he is a farmer, and the joint pain deeply affected his quality of life and it impacted his ability to drive his tractor. The steroid is a miracle drug.  No follow-up attempts are needed. No further information is expected.; Sender's Comments: Based on the temporal association the possibility of causal association between the event Remitting seronegative symmetrical synovitis with pitting oedema syndrome and the suspect drug BNT162B2 cannot be ruled out. 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 regulatory authorities, Ethics Committees, and Investigators, as appropriate.