The incidence of allergic rhinitis (AR) in Chinese adults was reported to be as high as 24.1% and 16.8% in children. The current symptomatic treatment has the disadvantage of poor efficacy and cannot change the natural course of the disease. Allergen immunotherapy (AIT) is the only causative treatment approved by the WHO, bringing a new option to patients with allergic diseases. The quality of allergen preparations is critical to the diagnosis and treatment of the disease, emphasizing the need for standardized preparations, and AIT treatment in the early stages of the disease may change the long-term progression of the disease. Recent studies have reported that the microbiome of patients with different efficacy of desensitization therapy is different and may be correlated with the clinical symptoms of patients, but no prospective studies have been reported.

Inclusion Criteria:

• Adult patients (18-65 years).
• Patients with canis familiari/felis domesticus/alternaria alternata allergic rhinitis were diagnosed based on clinical history and positive dust mite sensitization tests (skin prick test and/or specific IgE).
• Patients who visited the Department of Otolaryngology of the First Affiliated Hospital of Nanjing Medical University and selected sublingual spray desensitization.

Exclusion Criteria:

• Patients who refused to accept specimen and questionnaire collection.
• Patients who had nasal diseases other than allergic rhinitis, such as nasal papilloma and nasal malignant tumor.

Patients diagnosed with allergic rhinitis in the Department of Otolaryngology of the First Affiliated Hospital of Nanjing Medical University and selected sublingual spray desensitization.