Extreme PFAPA (Periodic Fever, Aphthous Stomatitis, Pharyngitis and Cervical Adenitis):
A Subgroup of PFAPA Patients with Shorter Intervals between Flares

Background and Aim: Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most common periodic fever syndrome in children and, by definition, episodes occur every 2 to 8 weeks. However, we noticed a higher frequency of attacks in a subset of our patients lasting less than 2 weeks (referred as extreme PFAPA – ePFAPA group). Therefore, we aimed to characterize demographic and clinical features of this group and to compare them to non-extreme PFAPA (nPFAPA) patients.

Methods: The medical records of patients with PFAPA attending the Schneider Children`s Medical Center of Israel from 3/2014 to 4/2021 [גא1] were retrospectively reviewed. Patients with concomitant familial Mediterranean fever were excluded. ePFAPA and nPFAPA groups were compared using Wilcoxon rank sum, Pearson`s chi-squared and Fisher`s exact tests.

Results: Out of 365 total PFAPA patients, 47 patients (12.9%) were identified as having ePFAPA. ePFAPA patients had earlier disease onset (age 1.7 vs 2.96 years, P<0.001) and diagnosis (age 2.94 vs 5.02 years, P<0.001). compared to nPFAPA patients. In addition, ePFAPA patients had even higher increased flares frequency after initiation of an abortive treatment with corticosteroids (72% vs 40%, P<0.001) and were more likely to be treated with colchicine prophylaxis (67% vs 26%, P<0.001). No other significant demographic or clinical differences were identified

Conclusion: ePFAPA patients are a discrete group of patients with earlier onset and diagnosis of PFAPA and with increased flares frequently after abortive therapy with steroids. Current study is underway to describe the long-term outcome of this group.