Levels of nasal exhaled hydrogen sulfide in the general population and allergic rhinitis patients

Background Objective measures used for the differential diagnosis and severity assessment of allergic rhinitis (AR) are still lacking. The involvement of hydrogen sulfide (H 2 S) in the development of AR indicates that nasal exhaled H 2 S (NeH 2 S) has potential as a biomarker to be used in AR patients. This study aimed to evaluate the application value of NeH 2 S measurement in the diagnosis and assessment of AR. Methods This study was a multi‐center cross‐sectional survey conducted in Northwestern China. Demographic information collection and rhinitis assessment were completed through questionnaires. The level of NeH 2 S and serum immunoglobulin E were measured. Results The level of NeH 2 S in general population ranged from 0 to 35 ppb, with a median value of 2 ppb. The NeH 2 S levels in seasonal allergic rhinitis (SAR) patients were significantly lower than those in general population (2 [1, 2.75] vs. 2 [2, 3] ppb; p  = .023), and the NeH 2 S value of the SAR group tended to be lower than that of the non‐allergic rhinitis (NAR) group (2 [1, 2.75] vs. 2 [2, 3] ppb; p  = .094). The subgroup of AR patients with symptoms lasting longer than 2 weeks per month had a lower NeH 2 S level compared with the subgroup of patients with symptoms lasting less than 2 weeks per month (2 [1, 2] vs. 2 [2, 3] ppb; p  = .015). Conclusion This study described the distribution range of NeH 2 S levels in the general population. Further study with larger sample size was needed to clarify the relationship between NeH 2 S level and AR.