Background: Special attention has been paid to the sequelae caused by SARS-CoV 2 infection (Long-COVID), the prevalence of these sequelae in patients with rheumatological diseases has not been studied in detail. As these patients have immunosuppressive therapy and this syndrome has inflammatory characteristics, we postulate that these patients will have a lower prevalence of sequelae. Methods: We conducted a retrospective, cross-sectional, single-center study in which we interrogated all the patients who had the diagnosis of rheumatological diseases who attended our hospital between August 1, 2021 and November 30 and who had a history of 3 or more months of SARS CoV2 infection. The interrogation consisted of a brief questionnaire on the persistence of symptoms 3 months after the event. Results: We included 64 patients: 19 patients with rheumatoid arthritis (RA), 21 patients with systemic lupus erythematosus (SLE), and 24 with other rheumatological diseases. Long COVID symptoms reported were similar to those described in the literature of patients without rheumatic diseases. The prevalence of fatigue was significantly lower in SLE compared to RA and the rest of the pathologies, but there were no other significant differences between them. Conclusions: The long COVID syndrome is common in patients with and without rheumatic diseases, and the prevalence of each of these symptoms differs little between these groups. A lower prevalence of post-COVID symptoms was seen in patients with SLE than in the rest of the rheumatological diseases, but after we run a binary logistic regression model, most of these differences were not significant and they did not differ much from the general population.

The COVID-19 pandemic represents a global health problem, which has been mitigated by the opportune introduction of vaccination programs. Although we already know the benefit that vaccines provide, these are not exempt from adverse events which can be mild to deadly, such as idiopathic inflammatory myopathies, in which a temporal association has not been defined. It is for this reason that we carried out a systematic review of all reported cases of vaccination against COVID-19 and myositis. To identify previously reported cases of idiopathic inflammatory myopathies associated with vaccination against SARS-CoV-2 we registered this protocol on the website of PROSPERO with identification number CRD42022355551. Of the 63 publications identified in MEDLINE and 117 in Scopus, 21 studies were included, reporting 31 cases of patients with vaccination-associated myositis. Most of these cases were women (61.3%); mean age was 52.3 years (range 19-76 years) and mean time of symptom onset post-vaccination was 6.8 days. More than half of the cases were associated with Comirnaty, 11 cases (35.5%) were classified as dermatomyositis, and 9 (29%) as amyopathic dermatomyositis. In 6 (19.3%) patients another probable trigger was identified. Case reports of inflammatory myopathies associated with vaccination have heterogeneous presentations without any specific characteristics: as a consequence, it is not possible to ensure a temporal association between vaccination and the development of inflammatory myopathies. Large epidemiological studies are required to determine the existence of a causal association.