Objective: Considering the concerns regarding the coronavirus disease‐2019 (COVID‐19) vaccine safety among pediatric patients with inflammatory rheumatic diseases (IRD) due to a lack of data, an urgent need for studies evaluating safety profiles of vaccines emerged.Methods: Among participants vaccinated by CoronaVac inactive SARS‐CoV‐2 or BNT162b2 messenger RNA (mRNA) COVID‐19 (Pfizer‐BioNTech) vaccine, healthy children under 18 and patients under 21 with an at least 1‐year follow‐up period in our department for a childhood‐onset rheumatic disease were included into this cross‐sectional study.Results: Overall, 246 subjects (141 [57.3%] females) (biologic group: 43, non‐biologic group: 180, healthy control group: 23) were eligible for the study. The median age was 15.34 (12.02‐20.92) years. The most common adverse events were fatigue (n = 68, 27.6%), headache (n = 44, 17.9%), myalgia (n = 38, 15.4%), arthralgia (n = 38, 15.4%), and fever (n = 35, 14.2%). Only 3 subjects (2 patients with familial Mediterranean fever, and one healthy child) were considered to experienced serious adverse events, since they required hospitalization. Local reactions were seen in 20 (8.13%), and 27 patients (12.1%) had disease flares within 1 month after the vaccines. Although it was significantly higher in those who received the BNT162b2 mRNA vaccine (P < .001), there was no significant relationship between adverse event frequency and age, gender, the existing diseases, ongoing treatment regimens and pre‐vaccination COVID‐19 histories.Conclusion: Although immunogenicity studies for efficacy of the vaccines and long‐term follow‐up studies for adverse events monitoring are required, our study indicates an acceptable safety profile of COVID‐19 vaccines and encourages children with IRD to be vaccinated.

Autoinflammatory diseases are characterized by recurrent fever attacks and clinical findings that arise from impaired natural immunity and spread to a wide variety of organ systems. The concept of autoinflammatory disease emerged after the definition of familial Mediterranean fever (FMF) and Tumor Necrosis Factor Receptor Associated Periodic Syndrome (TRAPS). Firstly, it is thought that this new group differs from the standard concept of autoimmune diseases, which is relatively better known in terms of basic features such as defects in innate immunity and the absence of antibodies. We have come a long way in understanding the genetic and pathogenetic mechanisms of this relatively new disease group in the past twenty years since they were first diagnosed. This growing understanding leads to some changes in the concept of autoinflammatory diseases. Recently, the definition of the autoinflammatory disease includes a wide range of diseases with different clinical features, mainly accompanied by changes in innate immune and rarely in humoral immunity. Owing to recent developments in molecular sciences and genetics, the spectrum of autoinflammatory diseases is rapidly expanding. In this review, clinical features, classification criteria, treatment options and long-term prognoses of Periodic Fever, Aphthous Stomatitis, Pharyngitis, Adenitis (PFAPA) syndrome, and other common autoinflammatory diseases are discussed in the light of current literature.

Humanity has recently gained a novel foe named coronavirus disease 2019. Although data so far mostly suggest that children are more likely to have a favorable disease course, new concerns have been raised because of recently reported pediatric cases with hyperinflammatory conditions resembling Kawasaki disease, toxic shock syndrome, and macrophage activation syndrome/hemophagocytic lymphohistiocytosis. Because the increasing evidence suggests that this recent hyperinflammatory condition emerged in the coronavirus disease 2019 era is a distinct clinical picture, the Centers for Disease Control and Prevention named this novel disease multisystem inflammatory syndrome in children. Even if this novel disease is rare, it seems to be highly fatal. Therefore, it is urgent to understand the pathogenesis of the disease to be able to establish the appropriate treatment regimes. Concerns regarding the diagnostic process and the management of the disease have been raised even among pediatricians. Therefore, we aimed to clarify this newly occurring enigma based on the current literature and our clinical insights. Cite this article as: Haslak F, Yıldız M, Adrovic A, Şahin S, Barut K, Kasapçopur Ö. A recently explored aspect of the iceberg named COVID-19: multisystem inflammatory syndrome in children (MIS-C). Turk Arch Pediatr 2021; 56(1): 3-9.