I could hardly move my index and little finger on both hands,; Rheumatoid arthritis; evere knee, feet, arm, finger, shoulder, and wrist pain/ the pain expanded to my feet, arms, and fingers.; Extensive and sustained joint pain that started several days after the second Moderna vaccination , the pain expanded to my feet, arms, and fingers.,pain expanded to shoulders and wrists; This spontaneous case was reported by a consumer and describes the occurrence of RHEUMATOID ARTHRITIS (Rheumatoid arthritis) in a 45-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.     Concurrent medical conditions included Heartburn since 15-Aug-2015 and GERD since 15-Aug-2015. Concomitant products included OMEPRAZOLE from 15-Aug-2015 to an unknown date for Heartburn, COD LIVER OIL [COD-LIVER OIL] from 01-Jan-2016 to an unknown date and MULTIVITAMINS [VITAMINS NOS] from 01-Jan-2016 to an unknown date for an unknown indication.   On 01-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 30-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 05-May-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced ARTHRALGIA (Extensive and sustained joint pain that started several days after the second Moderna vaccination , the pain expanded to my feet, arms, and fingers.,pain expanded to shoulders and wrists). On 01-Jun-2021 at 8:00 AM, the patient experienced PAIN IN EXTREMITY (evere knee, feet, arm, finger, shoulder, and wrist pain/ the pain expanded to my feet, arms, and fingers.). On 07-Jul-2021, the patient experienced RHEUMATOID ARTHRITIS (Rheumatoid arthritis) (seriousness criterion medically significant). On an unknown date, the patient experienced HYPOKINESIA (I could hardly move my index and little finger on both hands,). The patient was treated with PREDNISONE ongoing since an unknown date for Adverse event, at an unspecified dose and frequency; METHOTREXATE SODIUM (METHOTREXATE [METHOTREXATE SODIUM]) ongoing since an unknown date for Rheumatoid arthritis, at an unspecified dose and frequency and Physical therapy (Could only be cpmpleted when not in significant pain) for Hypokinesia. At the time of the report, RHEUMATOID ARTHRITIS (Rheumatoid arthritis) and HYPOKINESIA (I could hardly move my index and little finger on both hands,) outcome was unknown and PAIN IN EXTREMITY (evere knee, feet, arm, finger, shoulder, and wrist pain/ the pain expanded to my feet, arms, and fingers.) and ARTHRALGIA (Extensive and sustained joint pain that started several days after the second Moderna vaccination , the pain expanded to my feet, arms, and fingers.,pain expanded to shoulders and wrists) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 18-May-2021, X-ray limb: normal (normal) XR bilateral Knee - Normal. On 07-Jul-2021, Antinuclear antibody: positive (Positive) ANA Screen, IFA -Positive.. On 07-Jul-2021, Blood thyroid stimulating hormone (0.55-4.78): 1.876 (normal) TSH - 1.876 uIU/mL. On 07-Jul-2021, Blood urea nitrogen/creatinine ratio (7-20): 21.9 (High) Bun/Creatinine - 21.9. On 07-Jul-2021, C-reactive protein: 0.49 mg/dl (normal) 0.49 mg/dL (<1.0mg/dL). On 07-Jul-2021, Immunology test: negative (Negative) Lyme Disease Immunoblot testing - Non-Reactive. On 07-Jul-2021, Mean platelet volume (9.4-12.4): 8.9 (Low) MPV - 8.9 fL. On 07-Jul-2021, Neutrophil count (1.1-7.7): 0.5 (Low) 0.5 K/uL. On 07-Jul-2021, Renal function test: normal (normal) Normal. On 07-Jul-2021, Rheumatoid factor: 19 (High) 19 IU/mL (<14 IU/mL). On 07-Jul-2021, White blood cell count (4.0-10.5): 2.5 (Low) 2.5 K/uL. On 16-Jul-2021, Anti-cyclic citrullinated peptide antibody: >250 unit (High) CCP Ab IgG - >250 UNITS. On 22-Jul-2021, Hepatitis B surface antigen: non-reactive (Negative) Nonreactive. On 22-Jul-2021, Hepatitis C antibody (0.00-0.79): negative (Negative) Neg. On 22-Jul-2021, Mycobacterium tuberculosis complex test: negative (Negative) Negative TB Screen.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter considered RHEUMATOID ARTHRITIS (Rheumatoid arthritis), PAIN IN EXTREMITY (evere knee, feet, arm, finger, shoulder, and wrist pain/ the pain expanded to my feet, arms, and fingers.), HYPOKINESIA (I could hardly move my index and little finger on both hands,) and ARTHRALGIA (Extensive and sustained joint pain that started several days after the second Moderna vaccination , the pain expanded to my feet, arms, and fingers.,pain expanded to shoulders and wrists) to be possibly related.    Per report, the patient's knee pain worsened within two weeks after vaccination, forcing him to visit a local doctor who ordered several diagnostic blood and radiological investigations. While on treatment, the patient's knee pain progressed to his feet, arms, and fingers. The pain was worse at night and in the morning. The patient's arm pain felt like electric shock. They could not be held in position and would collapse at his side when placed in certain positions. In the mornings, the patient could hardly move his index and little fingers on both hands due to the pain in both hands. He was able to regain movement within one hour each morning after slowly moving his fingers. On 07-Jul-2021, the patient started physiotherapy which started improving his overall limb movement. The patient's doctor reported normal results for thyroid, liver and kidney function, blood sugar, C-reactive protein, and creatine phosphokinase. Complete metabolic profile and complete blood count with differentials were normal, except a low WBC and absolute neutrophil results. A 10-day course of steroid gave the patient a temporary relieve for several days, but the pain restarted and became worse than prior the steroid therapy. Following assessment of diagnostic results, the doctor suggested a diagnosis of rheumatoid arthritis due to the elevated cyclic citrullinated peptide (CCP) antibodies. The patient expressed she had been in pain for three months and desperately trying to understand what is happening to his body.  Treatment medications included non-steroidal anti-inflammatory drugs, and a plan to start the patient on disease-modifying antirheumatic drug treatment.  Based on the current available information which includes a temporal association between the use of the product and onset of the events, a causal relationship cannot be excluded. Arthralgia is consistent with the known safety profile of mRNA-1273.   Most recent FOLLOW-UP information incorporated above includes: On 20-Jul-2021: Follow up received and contained route of administration of vaccine. On 02-Aug-2021: significant Follow-up added to include reporter information. Added new lab data. Added treatment information. Concomitant medication. added thyroid function test, kidney function test, RA factor, C - reactive protein test, Sedimentation rate, blood sugar test. Added outcome, start date and causality for event.; Sender's Comments: Based on the current available information which includes a temporal association between the use of the product and onset of the events, a causal relationship cannot be excluded. Arthralgia is consistent with the known safety profile of mRNA-1273.