The Journal of Allergy and Clinical Immunology Global · Nov 2026
Clinical features of intermediate T2 asthma identified by blood eosinophil and exhaled nitric oxide
By Ercan S, Özuygur Ermis SS, Abohalaka R et al.
Background Archetypical asthma with high or low type 2 (T2) inflammation markers have been described, but the clinical features of individuals falling in between those groups remain poorly understood. Objective To describe the features of asthma with intermediate T2 markers in a general adult asthma population. Methods Participants with current asthma (n=896) from the population-based West Sweden Asthma Study were classified according to their T2 inflammation marker levels. Classification utilized widely-used cut-off values for blood eosinophil count (0.15 and 0.3×10⁹ cells/L) and fractional exhaled nitric oxide (FeNO; 20 and 30 ppb), and having clinically allergen-driven disease. Subsequently, the intermediate T2 markers group was compared to those with high and low T2 markers. Results The proportion of participants with intermediate T2 markers was 18.1%. While the prevalence of skin prick test positivity (43.2%) and nasal allergy (71.0%) in the intermediate group was similar to the T2-low group (45.3% and 68.0%, respectively), it was lower than in the T2-high group (86.3% and 88.9%, respectively). Spirometric features in the intermediate group more closely resembled those with high T2 markers than the low T2 markers group. Participants with intermediate levels of T2 markers reported emergency department visits due to asthma more frequently (11.2%) than those with high levels of T2 markers (8.1%) but less frequently than participants with low levels of T2 markers (15.1%). Conclusion Our results suggest that asthma with intermediate T2 biomarker levels appear to lie potentially in a transition zone, characterized by an asynchronous evolution of clinical traits. This underscores the need for an individualized management strategy that moves beyond the limitations of current biomarker-based guidelines.