AUTOINFLAMMATORY DISEASES IN RHEUMATOLOGY: RUSSIAN EXPERIENCE

Autoinflammatory diseases (AIDs) are characterized by periodic, sometimes self-limiting attacks that appear as fever and clinical symptoms resembling rheumatic ones, in the absence of autoimmune or infectious diseases. The group of AIDs encompasses a broad spectrum of nosological entities; some of them have been recently dealt with by rheumatologists.Objective: to define the spectrum of AIDs in the practice of a pediatric rheumatologist from the results of visits to the Russian Federal Rheumatology Center.Subjects and methods. The investigation enrolled patients who had visited the V.A. Nasonova Research Institute of Rheumatology in 2007 to 2015 for fever and other signs of a systemic inflammatory process in order to specify their diagnosis and to rule out infections, blood cancer, and other diseases. All underwent conventional rheumatologic examination, HLA Class A typing, and molecular genetic testing.Results and discussion. 101 patients aged 6.5 months to 60 years with AIDs were identified over 9 years and diagnosed as having the following diseases. Familial Mediterranean fever (FMF) was detected in 17 patients (the female to male (M/F) ratio was 6:11); Behсet's disease (BD) in 25 children (M/F, 14:11), cryopyrin-associated periodic syndromes (CAPS) in 17 patients, including Muckle–Wells syndrome in 13 (M/F, 4:9); chronic infantile neurologic cutaneous articular and neonatal onset multisystem inflammatory disease (CINCA/NOMID) syndrome in 4 (M/F, 3:1), periodic fever, aphthous stomatitis, pharyngitis, cervical adenitis (PFAPA) syndrome in 17 (M/F, 10:7), hyper-IgD syndrome/mevalonate kinase deficiency syndrome in 3 (M/F, 0:3), tumor necrosis factor receptor periodic syndrome (TRAPS) in 7 (M/F, 4:3), undifferentiated AID in 14, and Blau syndrome in one patient. The patients with BD were rather ethnically diverse: among them, there were representatives of North Caucasian peoples, Tatars, Uzbeks, Moldavians, and others; there were 7 ethnic Russians. There was a preponderance of Armenians among FMF patients (15/17). Ethnic Russians were predominant among the patients with other nosological entities. HLA-B5 antigen was found in 9 (36%) patients with BD. Molecular genetic analysis confirmed the diagnosis in virtually all the patients with monogenic AIDs.Conclusion. The most common AIDs in our practice were BD, FMF, CAPS, and PFAPA. The patients with CAPS were closest in clinical and laboratory presentations to those with rheumatic disease, particular to those diagnosed with systemic juvenile arthritis and this disease should be kept in mind in differential diagnosis. Our practical experience indicated that targeted therapy with interleukin 1 inhibitors was effective in CAPS patients. This treatment is able to substantially improve an initial poor prognosis.