Risk factors for periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome: a case-control study

The etiology and pathogenesis of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome are unclear. We performed a case-control study to evaluate potential environmental or lifestyle factors associated with PFAPA morbidity. We enrolled 119 patients with PFAPA syndrome who had undergone tonsillectomy in Oulu University Hospital between 1987 and 2007. We recruited 230 controls, matched for sex, birth date, and place from the database of the Population Register Center of Finland. All the patients and controls completed a questionnaire regarding exposure to environmental triggers during early childhood. Maternal smoking was more common among PFAPA syndrome patients than controls (23 vs. 14%; P = 0.005). PFAPA patients had lower breastfeeding rates than controls (94 vs. 99%; P = 0.006). No other environmental factors were associated with PFAPA syndrome, except having an aquarium at home ( P = 0.007). The patient group also used natural or herbal medicines more often than the controls ( P = 0.01). Conclusion : Maternal smoking and lack of breastfeeding, known risk factors for common childhood infections, were more common in patients with PFAPA syndrome than in matched controls. Environmental factors may be important in the pathogenesis of PFAPA syndrome and should be evaluated in future studies. What is Known: • The pathogenesis and genetics of periodic fever , aphthous stomatitis , pharyngitis , and adenitis ( PFAPA ) syndrome remain unsolved. • PFAPA syndrome has been shown to cluster in families. What is New: • Maternal smoking and lack of breastfeeding are more common in patients with PFAPA syndrome than in the controls. • Environmental risk factors may be important in the pathogenesis of the syndrome.