Abstract
Objective Systemic juvenile idiopathic arthritis is one of the subtypes of juvenile idiopathic arthritis. This type of disease accounts for approximately 10–20% of all cases of juvenile idiopathic arthritis. It typically affects both sexes equally and is usually present in children under 5 years. This study aimed to evaluate the demographic and clinical features of patients who were followed up for the diagnosis of sJIA in a single centre, the treatments they received, the responses to the treatment and the course of the disease.
Methods All patients with systemic juvenile idiopathic arthritis who were evaluated at Dr Sami Ulus Maternity Child Health and Diseases Training and Research Hospital, Department of Paediatric Rheumatology, between January 2017 and January 2020 were included in this study. Descriptive features, clinical information, medications, treatment responses and long-term prognosis of patients were evaluated retrospectively.
Results The study included 40 patients. 60% (n=24) of the patients were female and 40% (n=16) were male. The diagnosis age of the patients was 7.77±4.82 years and the patients were followed up for an average of 48±41 months. All of the patients had fever at the time of diagnosis. The 3 most common clinical signs after fever were arthralgia, hepatomegaly and lymphadenopathy (65, 55 and 50%, respectively). Ten patients (32.5%) had macrophage activation syndrome at admission. No significant difference was detected between the groups with and without macrophage activation syndrome concerning age, gender and clinical findings. Leukocyte, haemoglobin, platelet and erythrocyte sedimentation rates were significantly lower in the macrophage activation syndrome group compared with the other group, and ferritin was significantly higher. The C-reactive protein value was higher in the group without macrophage activation syndrome, but the difference was not statistically significant. While all patients received corticosteroid therapy as the initial therapy, 87.5% of these patients were administered pulse methylprednisolone therapy. In the follow-up, 21 patients (52.5%) needed biological treatment. Twenty-seven patients (67.5%) had a monocyclic course, 3 patients (7.5%) had a polycyclic course and 10 patients (25%) had a persistent polyarticular course.
Conclusion Early diagnosis and treatment of systemic juvenile idiopathic arthritis are important because of the risk of developing macrophage activation syndrome – the most lethal complication. In our evaluation, it was seen that laboratory parameters could provide more guidance than clinical findings. Although steroids are the cornerstone of therapy, biological agents are effective in patients who are not responsive to steroid therapy.
The bias of the question posed: a diagnostic “invisible gorilla”