Allergy Asthma Respir Dis.  2023 Oct;11(4):180-186. 10.4168/aard.2023.11.4.180.

Stratification of clinical and inflammatory phenotypes according to the urinary leukotriene E4 level in adult asthmatics

• Kang S
• Jang JH
• Jeon HS
• Ban GY
• Park HS

• KMID: 2547448
• DOI: http://doi.org/10.4168/aard.2023.11.4.180

Abstract

Purpose
Cysteinyl leukotrienes (CysLTs) have been recognized as key mediators associated with type 2 inflammation in the airways of asthmatic patients. CysLTs are associated with airway constriction, eosinophil recruitment/activation, and airway remodeling. The study aimed to understand the role of CysLTs in adult asthmatics in a real-world clinical setting.
Methods
One hundred five adult asthmatics who had maintained antiasthmatic medications were enrolled. Asthmatic subjects were classified into 2 groups according to urinary leukotriene E4 (uLTE₄) levels, and their clinical parameters and inflammatory mediators, including forced expiratory volume in 1 second (FEV₁) %, fractional exhaled nitric oxide (FeNO), blood eosinophil count, serum periostin (sPON), and urinary eosinophil derived neurotoxin (uEDN) were compared between the high-uLTE₄ and low-uLTE₄ groups.
Results
The prevalence of chronic rhinosinusitis (CRS), severe asthma, and aspirin-exacerbated respiratory disease (AERD) were significantly higher in the high-uLTE₄ group than in the low-uLTE₄ group. The high-uLTE₄ group had lower FEV₁% and maximal midexpiratory flow %, but higher FeNO levels than the low-uLTE₄ group. In addition, blood eosinophil count, sPON, and uEDN levels were significantly higher in the high-uLTE₄ group than in the low-uLTE₄ group. The presence of AERD and levels of FeNO, sPON, and uEDN were significantly associated with higher uLTE₄ levels in asthmatics.
Conclusion
CysLTs are associated with type 2 inflammation in the airways of asthmatic patients, contributing to the development of AERD, CRS, and asthma severity. The stratification of clinical phenotypes according to the uLTE₄ level could support optimizing anti-inflammatory therapy for better control of asthma.

Keyword

Asthma; Leukotriene; Asthma severity; Asthma control status; Eosinophil