145. Reactive arthritis secondary to mRNA vaccine with urticarial skin lesions with reversible rheumatoid serology

Background: A 20-year-old female presented with swelling of hands and feet. 3 days earlier she received mRNA BNT162b2 vaccine. She had swollen lips (Fig. 1A), right ankle, (Fig. 1B), wrists and MCP joints (Fig. 1C). She developed urticarial-rash affecting her legs (Fig. 1D).

Methods: Her bloods revealed elevated CRP 138mg/L. Despite prednisolone 40mg daily she developed dyspnoea, pruritus, angioedema requiring IM adrenaline, IV chlorphenamine and hydrocortisone. Blood and urine cultures, Coronavirus PCR, Influenza and RSV were negative.

Results: HLA B27, hepatitis B, C, chlamydia, gonorrhoea and HIV were negative. RF and anti-CCP were elevated at 20.2IU/ml [Normal<12] and 96.9u/ml [0-3.1] respectively. ANA was positive with elevated DsDNA 14 IU/ml [0-10.1], but negative crithidia and ENA.

Prednisolone was tapered over 6 weeks. 3 months after presentation there has been no recurrence with subsequent negative ANA, RF and anti-CCP. 

Conclusions: Reactive arthritis [ReA] typically manifests as asymmetric oligoarthritis 1-4 weeks after an STI or gastrointestinal infection. SAR-CoV-2 infection may also cause a ReA [1]. Our case highlights a case of ReA with anaphylaxis secondary to the mRNA BNT162b2 vaccine.  Our patient developed strongly positive rheumatoid serology indicating a possibility of early RA, but repeat serology was negative. Flare of rheumatoid arthritis after COVID-19 vaccination has been reported [2] however our patient had no further synovitis.

Disclosures: The authors have declared no conflicts of interest. No specific funding was received from any bodies in the public, commercial or not-for-profit sectors to carry out the work described in this manuscript. The patient provided informed consent to publish this case.

Figure 1. Swollen and erythematous lips (A).  Swelling of right ankle (B), Swollen MCP joints (C), urticarial skin lesions (D)