A40: Periodic Fever Syndromes in Canada: Results from a National Surveillance Program
Authors: Paul Dancey, Susann Benseler, Marco Gattorno, Anne K Junker, Ronald M. Laxer, Paivi Miettunen, Lesley Ann Turner
Journal: Arthritis & Rheumatology (2014)

Background/Purpose:

To estimate the incidence of periodic fever syndromes in the Canadian paediatric population, to describe the patterns of presentation, and to raise awareness in the medical community.



Methods:

This study was initiated though the Canadian Pediatric Surveillance Program (CPSP), and is being carried out over a three year period which will conclude in September 2014. The case definition includes patients less than 18 years of age presenting with a newly diagnosed periodic fever syndrome. Conditions under surveillance included Familial Mediterranean fever (FMF), Tumor necrosis factor receptor-associated periodic syndrome (TRAPS), Hyperimmunoglobulin D syndrome (HIDS), Cryopyrin-associated periodic syndromes (CAPS), Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA), and Undefined periodic fever syndromes. For each condition the study protocol outlined established clinical and/or genetic criteria for diagnosis. Participating pediatricians and pediatric subspecialists across the country are sent monthly reporting forms. Detailed questionnaires are completed by physicians who report a recent diagnosis. Submissions are screened for accuracy and confirmed cases then entered into a database.



Results:

During the 20 month period from September 2011 to December 2012 a total of 167 cases were reported. Of these cases, detailed questionnaires were completed on 126, with the remainder pending at the time of this report. 114 cases have been confirmed as meeting the criteria for one of the Periodic Fever Syndromes under surveillance, 55% of which had had genetic testing completed as part of their evaluation. Twelve cases were discarded. Amongst the 114 confirmed cases, PFAPA was most frequent (51%), followed by Undefined Periodic fever syndrome (37%). Also seen were FMF (11%), and one case of HIDS (1%). There were no cases of TRAPS, or CAPS, reported during the study period to date. Amongst the 42 Undefined Periodic Fever syndrome cases the reporting physicians described 11 as being suspected PFAPA, 5 suspected FMF, 3 suspected CAPS, and 1 suspected HIDS. In most cases this was because genetic testing was still pending at the time of reporting. The overall male to female ratio was 1.1:1. Amongst Undefined cases there was a male predominance with a male to female ratio of 1.6:1, whereas the male to female ratio was 0.6:1 for FMF. An equal number of males and females were reported for PFAPA. The most frequent fever associated manifestations for PFAPA included pharyngitis (79%), cervical lymphadenopathy (66%), stomatitis (59%), and fatigue (53%). For FMF most frequent were abdominal pain (69%), arthralgia (54%), pharyngitis (46%), and headache (46%). For Undefined cases most frequent manifestations were fatigue (45%), pharyngitis (38%), abdominal pain (36%), and lymphadenopathy (33%).



Conclusion:

Although rare periodic fever syndromes are identified across Canada each year. PFAPA, Undefined fever syndromes, and FMF are most frequently seen. We hope to have a more complete picture of the full spectrum and incidence of these autoinflammatory diseases in the Canadian population as genetic test results become available, and additional cases are identified through the end of the study in September 2014.