The effect of aspirin desensitization on novel biomarkers in aspirin-exacerbated respiratory diseases

Background: Patients with aspirin-exacerbated respiratory disease have been shown to benefit clinically from aspirin desensitization followed by chronic high-dose aspirin therapy. However, the mechanism of this phenomenon is still unclear. Objective: The aim of this study was to characterize the airway inflammatory response to aspirin desensitization and after treatment with high-dose aspirin for 6 months. Methods: Twenty-one adult patients with asthma, chronic polypoid sinusitis, and a convincing history of acute respiratory reaction to the ingestion of aspirin or nonsteroidal anti-inflammatory drugs were selected. These patients underwent an oral desensitization to aspirin over a 2-day period, followed by daily ingestion of aspirin 650 mg twice daily. Induced sputum samples and exhaled nitric oxide measurements were taken before the procedure, during the second day of the procedure, and after 6 months of treatment. Results: There was a significant elevation in both the exhaled nitric oxide level (P = .03) and sputum tryptase level (P = .05 ) during the desensitization process. After 6 months of aspirin treatment, sputum IL-4 (P = .0007) and matrix metalloproteinase 9 (MMP-9; P = .05 ) decreased significantly compared with baseline. Predesensitization to postdesensitization changes in MMP-9 and tissue inhibitors of metalloproteinases 1 were highly correlated (r = 0.79; P = .0003). Immediately after the desensitization, MMP-9 and tryptase were correlated (r = 0.82; P = .001), whereas IL-4 was inversely related with FMS-like tyrosine kinase 3 ligand (FLT3-L) (r = -0.79; P = .0008). There was a significant decrease in the average symptom score at 6 months. Conclusion: Consistent with previous reports, acute aspirin desensitization in patients with aspirin-exacerbated respiratory disease involves mast cell degranulation. In contrast, long-term treatment with aspirin involves suppression of IL-4 as well as downregulation of proinflammatory MMP-9 while T H 1 marker FLT3-L increases. (J Allergy Clin Immunol 2010;126:738-44.)