Nasal fluid secretory immunoglobulin A levels in children with allergic rhinitis

There is growing knowledge about the immunoregulatory and possibly preventative roles of immunoglobulin A (IgA) in allergic diseases. This study aimed to investigate secretory immunoglobulin A (SIgA) levels in the nasal fluid of children who were either being treated for their allergic rhinitis (AR) with intranasal mometasone furoate or were not receiving treatment.

The study population contained 55 children with persistent AR. Group I included 27 newly diagnosed AR patients not taking any medication and group II included 28 patients treated with intranasal steroids for at least 6 months. 27 healthy control subjects were also enrolled in the study. Total symptom scores (TSS) were calculated for each patient. Nasal secretions were obtained using a new modified polyurethane sponge absorption method, and samples were analysed by ELISA.

The median value for nasal fluid SIgA level in each group was 127.2μg/ml (interquartile range; 67.3-149.6) in group I, 133.9μg/ml (102.1-177.8) in group II and 299.8μg/ml (144.5-414.0) in the control group. Groups I and II both had statistically significant reductions in nasal fluid SIgA levels compared to the control group (p<0.001). However, there was no statistically significant difference between groups I and II (p=0.35). A statistically significant and negative correlation also existed between TSS and nasal fluid SIgA levels in both groups I and II (p=0.006, rho=-0.512 and p=0.01, rho=-0.481, respectively).

SIgA levels in the nasal fluid are significantly reduced in children with AR independent of treatment and are negatively correlated with the TSS.