Evaluation of nasal cytology in subjects with chronic rhinitis: a 7-year study

Background: No diagnostic test had been specifically developed to diagnose nonallergic rhinitis (NAR). Also a negative nasal smear for eosinophils does not rule out the diagnosis. There is a significant diagnostic problem in patients with NAR. How can we solve this problem? Objectives: Assessment of other cells than eosinophils present in the cytogram such as basophils, neutrophils, and goblet cells may help us to classify and management of diagnostic problem of rhinitis. We sought to characterize the cellular pattern of patients with allergic rhinitis (AR) and compare them with those of NAR. Methods: According to the skin prick test positivity or negativity, individuals were divided into AR and NAR groups, respectively. Allergic rhinitis group was further divided into seasonal, perennial, and mixed subgroups. Nonallergic rhinitis group was also divided into the following 5 subgroups according to the nasal smear cytologic result: basophilic, neutrophilic, eosinophilic, mixed, and nonallergic noninfectious type. So the frequency rates of the subgroups were calculated and also smear cytologic results were compared. Results: Frequency of AR was approximately equal to NAR in subjects with chronic rhinitis. Neutrophilic, eosinophilic, mixed, and nonallergic noninfectious types were the common types of NAR. An evident nasal eosinophilia was found in AR and eosinophilic NAR, whereas a higher percentage of goblet cells were determined in nonallergic noninfectious rhinitis. There is no significant difference between cytologic results from NAR and AR patients. Conclusion: In the patient with positive skin test result, the presence of nasal eosinophilia strongly supports the diagnosis of AR. No diagnostic test had been specifically developed to diagnose chronic NAR. Also, a negative nasal smear for eosinophils does not rule out the diagnosis. Assessment of other cells present in the cytogram such as basophils, neutrophils, and goblet cells may also provide valuable information for differential diagnosis and management of these conditions.