Age: 28.0
Sex: F
Vaccine: FLU3
Symptoms: Myalgia, Paraesthesia, Product administered at inappropriate site, Shoulder injury related to vaccine administration, Tenderness
Clinical narrative: The patient is a 29 yo female healthcare worker with a hx anxiety requests evaluation and recommendations due to AEFI after mandatory receipt of IIV #2 Jan 15, 2025 lot #AW1606B. She describes vaccinator error of initial selection of too low a site followed by overcorrection to atypically high, which was the site of antigen receipt followed by onset day 2 of left shoulder progressing pain, tenderness over her shoulder, affecting function, and paresthesia s. She also reports two episodes (2 weeks and 4 months post-receipt) of weakness, diffuse arthralgias, myalgias, fatigue and difficulty walking, muscle fasciculations, legs, vision field disturbance and tinnitus all which resolved in 7-10 days. The MRI 19 FEB (day 34 post- receipt) report states possible minimal long heads biceps tenosynovitis or subdeltoid bursitis, supporting post-immunization arthropathy. For her shoulder pain and injection arm symptoms: The description of vaccinator error, the timing of onset, and local paresthesia s are consistent with Post-Immunization Arthropathy (aka Shoulder Injury Related to Vaccine Administration [SIRVA], which is a medicolegal term). The differential dx would include other orthopedic etiologies including impingement syndrome, rotator cuff injury, biceps tendonitis, osteoarthritis or adhesive capsulitis, although these have all be documented as having been associated with SIRVA. Brachial neuritis is a consideration, but her description would be atypical (typical is severe pain followed by resolution and then onset of paresis/paralysis) and her neuro exam is normal, thus this is not likely. Her description is not suggestive of GBS. Post immunization arthropathy is thought to be a reaction to an unintentional injection of the vaccine into synovial tissues resulting in a robust immune-mediated inflammatory reaction to the musculoskeletal structures of the shoulder (tendons, ligaments, bursa, etc). Onset is within 48 hours after an injection. S/S include pain, decreased ROM, altered sensation, weakness. A description of  too high  is common. She received appropriate treatment, responded to PT and symptoms are now resolved. Concerning the systemic complaints of diffuse arthralgias, myalgias, fatigue, vision changes, tinnitus, leg numbness etc: Robust systemic responses to vaccine can produce arthralgias, myalgias, fatigue, however with an inactivated vaccine, onset is typically within a few days, has only for a few days duration and would not demonstrate recurrence four months later and does not explain her other symptoms. It is most likely a coincident event. Immune stimulation through natural infection or vaccines, can unmask an underlying condition, however her symptoms are nonspecific and currently resolved. I do not recommend further evaluation at this time and it does not support vaccine exemption. Should she have recurrence, she should f/u with PCP. Instruction was given for Future PIA Prevention as follows: -Both recipient and vaccinator should be at the same level (both seated, both standing) -Place your hand on your hip to rotate your elbow out. -Use of the appropriate needle length (most flu drives would use the correct needle for your height and weight). -Use of the thigh muscle as an alternative site. (Vaccines are not given in the gluteal muscles). -Avoid use of the left shoulder for vaccine receipt in the future. -Neither AEFI is a contraindication or precaution to future vaccine receipt. She should receive all vaccines as indicated per mandatory employment requirements and per ACIP recommendation for her personal health.