Reactive arthritis following COVID-19: cause for concern

Low-quality evidence suggests that COVID-19 may trigger reactive arthritis one to four weeks after the infection. Post COVID-19 reactive arthritis resolves within a few days, and no additional treatment is required. Established diagnostic or classification criteria for reactive arthritis are missing, and a deeper understanding of the immune mechanism related to COVID-19 prompt us to further investigate the immunopathogenic mechanisms capable of promoting or contrasting the development of specific rheumatic diseases. Caution should be exerted when managing post-infectious COVID-19 patient with arthralgia.

Though reactive arthritis is commonly triggered by sexually transmitted or gastrointestinal infections, syndromes consistent with reactive arthritis have been observed following Middle East respiratory syndrome, HIV, Dengue, Chickungunya, and Parvovirus B19 [32].
Given the intrinsic nature of case reports, it is unclear how generalisable these findings are. High variability in patient characteristics, diagnosis, examinations, and treatment were evident. Established diagnostic or classification criteria for reactive arthritis are missing, and a deeper understanding of the immune mechanism related to COVID-19 may offer a useful opportunity to further investigate the immunopathogenetic mechanisms capable of promoting or contrasting the development of specific rheumatic diseases.
Concluding, low quality evidence suggests that COVID-19 can target the musculoskeletal system causing reactive arthritis at its post-infectious stage. Caution should be used while managing post-infectious COVID-19 patient with arthralgia. It is unclear whether this condition can be prevented, whether previous vaccinations exert a preventive effect, and what the long-term sequelae of COVID-19-related reactive arthritis are.
Author contributions FM: literature search, writing; JK: revision and supervision; NM: synthesis, revision, supervision. All authors have agreed to the final version to be published and agree to be accountable for all aspects of the work.
Funding Open Access funding enabled and organized by Projekt DEAL. The authors received no financial support for the research, authorship, and/or publication of this article.

Data availability
The datasets generated during and/or analysed during the current study are available throughout the manuscript.

Declarations
Conflict of interest The authors declare that they have any competing interests for this article.
Ethical approval This study complies with ethical standards.

Consent to publish Not applicable.
Registration and protocol The present review was not registered.
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