Vitamin D deficiency as a risk factor for PFAPA syndrome

The periodic fever, aphthous stomatitis, pharangytis and cervical adenitis (PFAPA) syndrome, is an idiopathic chronic disease of non-hereditary origin, primarily affecting pre-school children and is the most common periodic fever disorder in children. Rapid response to corticosteroid treatment suggest an immune dysregulation. Recently, emerging evidence suggest that vitamin D plays an important role in immunity regulation. The aim of our study was to assess the vitamin D levels in children with PFAPA syndrome.

This study was conducted prospectively. We have consecutively evaluated 50 patients after having excluded other causes of recurrent fever between May 2017 and May 2018 in addition to age-matched 50 patients as control group. All patients has complete physical examination and laboratory tests. Laboratory tests included complete blood count, C-reactive protein (CRP), and vitamin D levels. Serum 25 (OH) vitamin D levels were measured in all patients twice yearly.

Vitamin D levels was 18 ± 10 ng/ml in the patient group and 35 ± 13 ng/ml in the control group. There was statistically significant difference between the groups (p < 0.001). 38 patients from the PFAPA group and 20 patients from the control group had low vitamin D levels. Multivariate logistic regression analysis showed that CRP (odd ratio (OR) = 2.7, 95% confidence interval (CI) = 2.4-4.1) and serum 25 (OH) vitamin D levels <30 ng/ml OR = 2.1, 95% CI = 1.8-2.5) were associated with PFAPA occurrence.

We found strong correlation between PFAPA and vitamin D insufficiency. Hypovitaminosis D can be a significant risk factor for PFAPA episode recurrence.