The frequency and clinical course of SARS-COV2 infection in children with juvenile idiopathic arthritis

Introduction: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), first reported from the Wuhan city of China in December 2019, swept the world in a few months and became a global health emergency of primary international concern continues to be a priority health problem. Recent studies suggest that subjects with autoimmune disorders (JIA, RA, SLE) do not have an increased risk to get Sars-Cov2. Juvenile Idiopathic Arthritis (JIA) is an inflammatory chronic disease concerning joints and others structures. According to International League of Association for Rheumatology (ILAR) seven subtypes of arthritis can be defined in relation with the number of joints and the extra-articular involvement occurring in the first six months of disease. NSAIDs and intra-articular steroids represent the first line treatment for JIA. Systemic steroids, disease modifying anti-rheumatic drugs (DMARDs) and biologic drugs are used in children with severe disease. Objectives: To evaluate the incidence and the impact on the disease course of Sars-cov2 infection in a group of children affected from juvenile idiopathic arthritis in treatment with Methotrexate and/or biological drugs. Methods: This study includes 77 children affected from JIA (55 females, 22 males). JIA diagnosis was made according to ILAR criteria and treatment was assigned with recommendations of the American College of Rheumatology. For each patient we recorded the type and the duration of pharmacological treatment, JIA subtype and relapses (defined according to Wallace criteria). During follow up visit from Nov 1st, 2020 to April 30th, 2021 we investigated in each patient history of Sars-Cov2 infection and related symptoms, diagnostic tests for Sars-Cov2. Results: The mean age at the last follow-up visit was 13.3±5.61 years. Thirteen out of 77 patients was affected Sars-Cov2 infection, none of them needed to be hospitalized. The most common symptom was headache (8 of 13 patients), followed by myalgia (6 of 13), fever (4 of 13), anosmia or dysgeusia (3 of 13), upper respiratory tract symptoms (3 of 13) and nausea (3 of 13). Five out of 13 patients were asymptomatic (38,5%). The mean duration of Sars-Cov2 infection was 12,5 days (confirmed with nose pharyngeal swab). In the group of patients with Sars-Cov2 infection 4 of 13 (30%) were in treatment with MTX, 2 of 13 (15%) with both MTX and biological drugs, 5 of 13(38%) with biological drugs, 2 of 13 (15%) with NSAIDs. In the group of patients without Sars-Cov2 infection 37 of 64 (48%) patients were in treatment with MTX, 32 of 64 (41,5%) with biological drugs, 18 of 64 (28%) with both MTX and biological drugs, 10 of 64 (15,6%) with NSAIDs. We didn’t find a higher risk to contract Sars-Cov2 infection in patients under MTX treatment (48% vs 46.15 %; p value 0.6416), in ones under MTX and biological drugs (28.1% vs 15.4%p value 0.543) or in ones under only biological therapy (50% vs 53.8% ; p value 0.231). We found that in patient with JIA the risk to get Sars-Cov2 infection is not related to the treatment. The percentage of JIA relapses was higher in patients with Sars-Cov2 infection than in the ones without infection (53,8% vs 9%; p value 0.0004). Conclusion: Treatment with MTX or biological drugs did not increase the risk to get Sars-Cov2 infection. The frequency of JIA relapses was higher in patients who got Sars-Cov2 infection than in ones who didn’t get it