Inflammatory comorbidities ın the largest pediatric Familial Mediterranean fever cohort: a multicenter retrospective study of Pediatric Rheumatology Academy (PeRA)-Research Group (RG)

Abstract

Aim The aim of this study was to investigate the frequency and type of FMF-associated inflammatory diseases in a large FMF pediatric patients and to compare them to those FMF patients without concomitant inflammatory diseases.Materials and methods Familial Mediterranean fever patients enrolled in the Pediatric Rheumatology Academy (PeRA)-Research Group (RG) were included. The patients were divided into two groups according to concomitant inflammatory disease as FMF patients who had a concomitant inflammatory disease (group 1) and FMF patients who did not have a concomitant inflammatory disease (group 1). The clinical findings and treatments were compared between the two groups.Results The study group comprised 3475 patients with FMF. There were 294 patients (8.5%) in group 1 and 3181 patients (91.5%) in group 2. Juvenile idiopathic arthritis (n = 136) was the most common accompanying inflammatory disease. Arthritis, M694V homozygosity, and the need for biological therapy were more frequently observed in Group 1 (p < 0.05). Fever and abdominal pain were more frequently detected in Group 2 (p < 0.05). FMF patients with concomitant inflammatory diseas more frequently demonstrated colchicine resistance. There were no significant differences in the median attack frequency, chest pain, amyloidosis, erysipelas-like erythema, or family history of FMF between the two patient groups.Conclusion To the best of our knowledge, this is the largest pediatric cohort reviewed to date. FMF patients may have different clinical profiles and colchicine responses if they have with concomitant inflammatory diseases.