Evaluation of Serum Immunoglobulin Concentrations During PFAPA Attacks

This study aimed to compare total serum IgG, IgA, and IgM concentrations between children sampled during periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) attacks and an age-similar control group and to examine acute-phase markers, including serum amyloid A (SAA). The study included 65 children with PFAPA sampled during an attack and 45 age-similar controls who were clinically healthy at the time of sampling and had no known systemic disease. The total IgG, IgA, and IgM concentrations and the frequency of values below the age-specific reference range were compared between the groups. C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, and SAA levels compared between the groups. Clinical and demographic data were obtained from medical records. The median age in the PFAPA group was 56 months, and in the control group, it was 57 months. Total IgG, IgA, and IgM concentrations were not different between the groups (p=0.897, p=0.173, and p=0.304, respectively), and values below the age-specific reference range were rarely observed in both groups. In contrast, CRP, ESR, fibrinogen, and SAA levels were higher in the PFAPA group. The median SAA level was 300.0 mg/L (n=51) in the PFAPA group and 21.8 mg/L (n=28) in the control group (p=0.011). The findings indicate that, despite a marked acute-phase response during PFAPA attacks, total immunoglobulin deficiency is uncommon.