Salivary Eosinophil Cationic Protein in Allergic Rhinitis

Eosinophil cationic protein (ECP) plays a significant role in the pathogenesis of atopic diseases such as allergic rhinitis (AR) and asthma. Using saliva as a diagnostic material is a non-invasive, simple method. Analysis of ECP in saliva was shown as an alternative diagnostic contribution in patients with asthma. In this study we aimed to assess a possible association between the levels of salivary ECP and the diagnosis of AR by comparing serum ECP and salivary ECP levels.

Thirty-five allergic rhinitis patients (study group) sensitive to Dermatophagoides farinae (D2) in skin prick test (SPT) and 35 nonallergic, SPT negative, healthy volunteers (control group) were included in the study. Salivary ECP, serum ECP and specific IgE D2 levels were measured.

Distribution of age and gender were similar in the study and the control groups (p>0.05). Serum specific IgE D2 levels were significantly higher in the study group compared to the control group (p<0.001). ECP levels in saliva and serum did not show any significant difference in between study and control groups (p=0.738; p=0.796, respectively). No significant difference was found between the levels of ECP in between the serum and the saliva of study and control groups. (p=0.504; p=0.589, respectively). There was no significant correlation between saliva and serum ECP levels of both groups.(r=-0.191/p=0.114).

Serum and saliva ECP levels seem close to each other and were comparable in both groups, but we did not find any correlation between them Although we hypothesized that saliva ECP may be used as a non-invasive method for the diagnosis of AR, it seems that this parameter is not helpful in diagnosis of AR.