Casting Light on The Potential Connection: Exploring the Relationship Between Periodic Fever, Aphthous stomatitis, Pharyngitis and Cervical Adenitis (PFAPA) syndrome and Behҫet in the Druze Population in Israel

Abstract Objectives: To characterize the clinical presentation of PFAPA and the response to treatment in an ethnic subgroup- Druze and analyze the differences compared to other ethnic groups. Study design: Retrospective data was collected from medical records of patients with PFAPA attending 2 pediatric tertiary medical centers in Israel between March 2014-December 2022. Patients with concomitant familial Mediterranean fever were excluded. Ethnicity was categorized as Mediterranean, non-Mediterranean, multiethnic and Druze. Results: Of 386 patients with PFAPA, 52 were with a corresponding FMF diagnosis (PFAPA/FMF) and information was lacking regarding FMF status in 9 patients. The study included 317 PFAPA patients, 178 (56.2%) of which were of Mediterranean descent (Sephardic Jews or Israeli Arabs), 87 (27.4%) were multiethnic, 19 (6%) were of non-Mediterranean descent (all Ashkenazi Jews), and 33 (10.4%) were of Druze ethnicity. No noteworthy differences in age of onset or age of diagnosis were found among ethnic groups. Clinical presentation analysis revealed statistical significance (P=0.025) of the prevalence of abdominal pain across ethnic groups. No significance was found in the regarding other symptoms including pharyngitis, adenitis, aphthous, myalgia, arthralgia, rash, and headache. No significant association was found between the response to treatment and ethnic group. Genetic testing was performed in 127 patients, no significant association was shown between mutations number and ethnic origin. Conclusion: The clinical presentation of PFAPA in patients of Druze ethnicity is not significantly different from other ethnic groups in Israel. This finding fails to support the hypothesis that PFAPA is on the Behҫet spectrum.