Background: Analgesic intolerance (AI) is an important diagnostic feature of disease progression in patients with chronic rhinosinusitis (CRS) accompanied by nasal polyps (CRSwNP) and asthma.
Objective: The aim of the present study was to determine whether increasing the concentration of acetylsalicylic acid (ASA) used in the diagnostic nasal challenge would improve detection of ASA intolerance (NSAIDs-exacerbated respiratory disease, N‑ERD).
Methods: Patients with CRSwNP, asthma, and with (CRSwNP-AAI, n = 20) or without (CRSwNP-A, n = 15) anamnestically reported AI, as well as control subjects with CRS but no nasal polyps, asthma, or AI (n = 15), were challenged nasally with 16 mg ASA and, in case of a negative result, with 25 mg of ASA.
Results: In CRSwNP-AAI subjects, the challenge with 16 mg ASA resulted in detection of AI in 80% of cases; increasing the challenge of ASA to 25 mg improved the AI detection to 95%. In CRSwNP-A subjects, the detection of AI increased from 40% (16 mg ASA) to 53% (25 mg ASA). In the control group, no reaction to nasal ASA challenge was detected. No difference in the diagnosis of positive reactions after provocation was found when using the German vs. the European recommended evaluation criteria. Mild pulmonary symptoms occurred in 2 (10%) CRSwNP-AAI patients following the 16 mg ASA challenge.
Conclusion: In patients with CRSwNP, asthma, and anamnestic AI, nasal provocation can effectively confirm the diagnosis of N‑ERD and can also be recommended for patients with recurrent CRSwNP and asthma but without reported AI. Increasing the ASA challenge to 25 mg increases the overall detection rate.
Keywords: Analgesic intolerance; CRSwNP; N-ERD; Nasal ASA challenge; Nasal polyps.