ABSTRACT
Background. Several studies and cohorts with adult populations with rheumatic diseases (RD) were performed since pandemic outbreak. RD patients were more susceptible to infections and may develop severe forms of COVID-19, since they present immunosuppressive mechanisms inherent to the disease itself and to its treatment. Healthy children and adolescents seem to be less infected and present milder diseases. However, juvenile dermatomyositis patiets and immunosuppressed children have not been extensively studied. The objectives of the study are to evaluate asymptomatic SARS-CoV-2 infection in pediatric RD patients, to identify the risk factors related to contagion and to describe demographics and the profile of COVID-19 in juvenile dermatomyositis (JDM) patients followed. Methods. A cross-sectional study was conducted in March 2021, including 77 pediatric RD patients followed at a Brazilian tertiary hospital and 45 healthy controls. Data was obtained through a questionnaire applied to outpatients during the month of March 2021, before the vaccine, and contained demographic data, symptoms compatible with COVID-19 over the past year, and contact with people with confirmed COVID-19. Patients' medical records were reviewed to access data regarding disease and current medications. A qualitative immunochromatographic SARS-CoV-2 test was performed in all participants. All patients who were using rituximab or intravenous human immunoglobulin, or had symptoms of COVID-19, were excluded. Results. Patients' group included 11 (14.3%) JDM patients, 31 (40.2%) JIA, 25 (32.4%) JSLE, six patients with vasculitis, two with SS, one MCTD and one with autoinflammatory syndrome. Patients and controls were similar in terms of female gender (70.1% vs. 57.8%, p=0.173), median age (14 vs. 13 years, p=0.269) and SARS-CoV-2 serology positivity (22% vs. 15.5%, p=0.481). 80.5% of rheumatic patients were in use of immunosuppressive drugs, 27.3% of them using corticosteroids, 33.3% in high doses, and 7.8% on immunobiologicals. No statistical differences were found between positive (n=17) and negative serology (n=60) patients regarding demographic/socioeconomic data, contact with people with confirmed COVID-19, use and number of immunosuppressive drugs, use and dose of corticosteroids, use of hydroxychloroquine and immunobiological drugs (p>0.05). Regarding the profile of JDM patients, 6/11 (54%) were female, the median age was 13 years (range 9-17) and 3/11 (27%) presented COVID-19 serology positivity. 2/11 were in immunosuppressive treatment, however none of them were in use of glucocorticoids and biologic agents. Conclusions. Pediatric JDM and other rheumatic diseases patients were infected at the same rate as healthy ones. Neither the underlying pathology nor its treatment seemed to interfere with the contagion risk.