The Relationship between Olfactory Reduction and Middle Turbine Eosinophilia (Expression of CLC Gene) in Patients with Chronic Sinusitis

Considering the possible role of CharcoL leyden Crystal (CLC) gene in olfactory reduction, this study was performed to determine the relationship between olfactory reduction and middle turbine eosonophilia in patients with chronic sinusitis.

In a cross-sectional study, 45 patients with chronic rhinosinusitis who referred to Alzahra and Ayatollah Kashani hospitals of Isfahan, Iran, during the years 2019-2020 were selected, and a biopsy of the middle turbine was performed, and the expression of CLC gene was examined using real time polymerase chain reaction (PCR) test. Patients' olfactory status was assessed with methanol test questionnaires (CCCLC) and Sino-nasal outcome test-22 (SNOT-22), and the relationship between CLC gene expression and olfactory power was evaluated.

The mean olfactory score of the subjects was 4.73 ± 1.27, which was 5.58 ± 0.81 and 3.58 ± 77 in the negative and positive CLC subjects, respectively, and the CLC negative subjects had a higher olfactory level (P < 0.001). The mean score of SNOT-22 in all patients was 83.49 ± 14.88 and in the two groups of CLC negative and positive was 77.58 ± 15.43 and 91.58 ± 9.54, respectively, and the difference between the two groups was significant (P = 0.001).

The findings of the present study show that there is a significant relationship between CLC gene expression and decreased sense of smell in patients with chronic rhinosinusitis, and the sense of smell is lower in CLC positive patients.