Due to the ongoing COVID-19 pandemic and the lack of appropriate and effective treatments for COVID-19, the prevention of COVID-19 pandemic by vaccination has become of paramount importance. A study of 1266 RD patients showed 54.2% patients willing to get vaccinated against COVID-19, 32.2% uncertainty and 13.6% unwillingness to get vaccinated . The main concerns reported by patients that uncertainty or unwillingness to get vaccinated were the scarcity of the possible induction of a flare of their disease, and the risk to develop side effects . Several studies gave a reassurance for a good safety profile of the COVID-19 vaccines in adult RD patients, with most AEs being transient and mild [5–14]. Inactivated COVID-19 vaccines seem to be safe in pediatric RD patients, but no data are available.
In our study, no serious AEs were reported and the majority of AEs were transient and remission within a few days. AEs were recorded in 34 (17.7%) patients after the first dose of vaccine, and 97.5% were self-limited. AEs were recorded in 30 (15.9%) patients after the second dose, and 100% were self-limited. There were high amounts of heterogeneity about total AEs in reported studies, with AEs recorded in 26%-60.22% of patients [5, 6, 9]. Rotondo C et al. found patients in control of their RD had a lower risk in developing AEs . And all patients in our study are stable.
Arthralgia was reported in 3.42%-34.7% in patients with RD after vaccination, and 0.83%-19% in controls [5, 7, 8]. Three JIA patients experienced arthralgia after vaccination was confirmed as mild arthritis flare in this study. As we known, multiple factors could trigger arthritis flare, such as infection, stress and poor medication adherence. A study about risk of possible arthritis flare was compared among vaccine recipients and non-vaccinated individuals with rheumatoid arthritis by Li X et al., and the result showed no evidence of increased risk of possible arthritis flare among patients with rheumatoid arthritis who were fully vaccinated with mRNA or inactivated virus COVID-19 vaccines . Flare was self-limited in two of our patients. Flare was manageable and reversible in the third patient by addition of a non-steroidal anti-inflammatory drug.
Two patients with a history of HSP appeared a purpuric rash after vaccination. Relapses are common in HSP, the frequency of relapses reported in previous studies ranges from 2.7–51.7%, and the relapse of cutaneous rash was 88.7% . Among vaccines, measles-mumps-rubella vaccine showed an increased risk of HSP . De Novo HSP following exposure to COVID-19 immunization were reported in several studies in general population [19, 20]. There were reported about patients with a history of HSP received COVID-19 vaccination showed HSP purpura reactivation and booster [21–23]. Both two patients in our study showed a self-limited benign course without any management.
Here, the occurrence of relapsing of underlying RD were recorded in 5 (2.6%) of patients, only 1 (0.5%) needed symptomatic treatment. Geisen UM et al. reported not any flares in the context of either vaccination time points . Furer V et al. reported a worsening of the symptoms of underlying RD in 2.53% of patients after the first dose and 1.79% after the second one . Flares of existing systemic rheumatic disease were reported by 13.4% of participants, with 4.6% requiring a new or increased dose of medication to treat the flare . Spinelli FR et al. confirmed a disease flare in 2.8% after vaccination, in up to 5 months of follow-up, they detected the incidence rate of RD reactivation was 0.007 person/month . Concerns about the safety of other vaccines have been raised in sporadic reports and a study showed Systemic lupus erythematosus reactivation after HPV vaccination, with a fare rate of 12.6% . Several studies all demonstrated low incidence rate of disease reactivation after COVID-19 vaccines.
This study has some limitations. First, laboratory tests were no performed to confirm the flare. Secondly, it would have been ideal to compare the results with real-world data of the normal population. Lastly, it was a monocentric cohort study, further multicentric studies could provide additional information.