FRI0538 MAY SOME OF THE MEFV GENE VARIANTS CAUSE PFAPA SYNDROME LIKE SYMPTOMS?
Authors: YILDIZ Mehmet, Amra Adrovic, Ipek Ulkersoy, Neslihan Gucuyener, Oya Koker, Sezgin Sahin, Kenan Barut, Ozgur Kasapcopur
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> PFAPA syndrome is characterized by periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis. As diagnosis usually depends on clinical diagnostic criteria, sometimes it can be difficult to distinguish this clinical entity from the other periodic fever syndromes, especially in regions endemic for FMF. <h3>Objectives</h3> The objective of the study is to evaluate the PFAPA patients' <i>MEFV</i> gene variation frequencies (if it was performed) and relations between detected variants and clinical manifestations in pediatric PFAPA patients. <h3>Methods</h3> Nine hundred and thirty-seven patients that were recorded to our database as PFAPA syndrome were evaluated. Patients were reached by phone and asked about characteristics of their fever episodes, presence of acute phase reactant elevation, pharyngitis, aphthous stomatitis/cryptic tonsillitis, cervical lymphadenopathy, arthralgia, arthritis, abdominal pain, headache, nausea or vomiting, chest pain, diarrhea, skin changes, myalgia and conjunctivitis in the course of fever attack, if they had tonsillectomy, if they were attack-free after tonsillectomy and if they had clinical response to steroid or colchicine. <h3>Results</h3> There were 937 PFAPA patients in our database. <i>MEFV</i> gene analysis was performed in 407 (%43) of PFAPA patients and 305 of them had at least one mutation. Most common <i>MEFV</i> mutations of patients were: R202Q heterozygotes (25,9%), M694V heterozygotes (24,2%), E148Q heterozygotes (13,4%), P369S heterozygotes (9,8%) and V726A heterozygotes (8,6%), respectively.%45.8 of detected mutations were located in exon 2,%40,3 of them were located in exon 10 and%13,9 of them were located in exon 3 of the <i>MEFV</i> gene. Patients were divided into five groups according to their mutations' localization and groups were compared according to clinical features. There were significant differences between groups according to presence of pharyngitis, arthralgia, abdominal pain, myalgia and tonsillectomy history (Table 1). <h3>Conclusion</h3> In this study, we reported increased frequency of <i>MEFV</i> mutations in a large PFAPA patients cohort. Frequency differences of clinical features between groups suggest that some of the <i>MEFV</i> gene mutations may modify phenotype of PFAPA syndrome. Furthermore, underlying <i>MEFV</i> gene mutations possibly lead to PFAPA like clinical presentation in FMF patients. Another remarkable finding of this study is the relatively high P369S mutation rates in patients with PFAPA syndrome. <h3>References</h3> [1] Pehlivan E, Adrovic A, Sahin S, et al. (2018). PFAPA Syndrome in a Population with Endemic Familial Mediterranean Fever. The Journal of pediatrics, 192, 253-255. [2] Yamagami K, Nakamura T, Nakamura R, et al. (2017). Familial Mediterranean fever with P369S/R408Q exon3 variant in pyrin presenting as symptoms of PFAPA. Modern rheumatology, 27(2), 356-359. <h3>Disclosure of Interests</h3> None declared