Pulmonary involvements in systemic juvenile arthritis

Abstract

Background Systemic juvenile idiopathic arthritis (sJIA) is a chronic inflammatory disease of childhood. Pulmonary involvements in sJIA have been recently described. Herein, we assess unusual clinical and radiological features of patients with sJIA, and possible risk factors for pulmonary involvements in sJIA. Methods A total of thirty-nine patients with sJIA were retrospectively enrolled. Data extracted included demographics, medical history, clinical manifestations, laboratory results, serum cytokine levels, radiological findings, management, and prognosis. Results Macrophage activation syndrome (MAS) had been observed at the initial diagnosis or during disease flares in eleven patients (11/39, 28%). Cerebral venous sinus thrombosis was observed in one patient with paroxysmal headache during the MAS phase. Twenty-three patients demonstrated abnormal radiological features on chest Computed Tomography (CT). Only eleven patients had subtle respiratory symptoms with normal oxygen saturation. Eight patients had lung disease (LD) before biologic exposure. sJIA-LD occurred in another six patients after the introduction of tocilizumab. All these patients continued to receive tocilizumab therapy, and sJIA-LD was improved in twelve patients with complete resolution of pulmonary presentations, and partially relieved in two patients. Only one of the two patients with possible anaphylaxis to tocilizumab presented with LD. Severe sJIA-LD was found in two patients with trisomy 21 and Kabuki syndrome, respectively. Conclusions Pulmonary involvements are increasingly observed in children with sJIA. Possible high risks for sJIA-LD include the occurrence of MAS, some inherited diseases, and evidence of drug hypersensitivity. It is still a question of whether IL-1/IL-6 inhibitor exposure increases the risk of sJIA-LD. Vasculitis and thrombosis should be considered in sJIA during the MAS phase, particularly in patients with pulmonary involvements. Trial registration: Not applicable; this was a retrospective study.