Objective  To analyze the expression levels of serum amyloid A (SAA) in patients with allergic and non-allergic asthma, and explore the correlation between SAA and acute exacerbation severity and identify biomarkers of allergic asthma. 

Methods  Asthmatic patients treated in the Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University from 2018 to 2019 were collected and divided into allergic asthma and non-allergic asthma groups according to the allergen test results. The SAA levels of the two groups of patients were then compared. The correlation between total IgE, FeNO, EOS and allergen-specific IgE levels were analysed. Logistic regression analysis was used to explore the relationship between SAA and allergic asthma. 

Results  A total of 127 patients were included in study, with an average age of 50.5±16.6 years, of which 69 (54.3%) were female, 57 patients had allergic asthma and 70 had non-allergic asthma. Patients with allergic asthma had significantly higher SAA levels than those with non-allergic asthma [(26.8±27.4) mg/L vs. (9.1±5.8) mg/L)]. The level of SAA in patients with severe to severe acute allergic asthma was (55.0±16.4) mg/L, which was significantly higher than that in patients with mild to moderate acute allergic asthma (13.8±13.0) mg/L. SAA level in allergic asthma patients was positively correlated with levels of allergen sIgE (r=0.398, P=0.044). There were no correlations between SAA and total IgE, FeNO and EOS%. SAA (OR=1.138, P<0.001) and total IgE (OR=1.015, P<0.001) were predicting factors for allergic asthma.  

Conclusion  The level of SAA in patients with allergic asthma was higher than that in patients with non-allergic asthma and was correlated with allergen sIgE levels. SAA may be used as a predicting factor for allergic asthma.

1.中华医学会呼吸病学分会哮喘学组. 支气管哮喘防治指南(2020年版)[J]. 中华结核和呼吸杂志, 2020, 43(12): 1023-1048. [Asthma group of Chinese Throacic Society. Guidelines for bronchial asthma prevent and management(2020 edition)[J]. Chinese Journal of Tuberculosis and Respiratory Diseases, 2020, 43(12): 1023-1048.] DOI: 10.3760/cma.j.cn112147-20200618-00721.

2.Ish P, Malhotra N, Gupta N. GINA 2020: what's new and why?[J]. J Asthma, 2021, 58(10): 1273-1277. DOI: 10.108 0/02770903.2020.1788076.

3.Büyüköztürk S, Gelincik AA, Genç S, et al. Acute phase reactants in allergic airway disease[J]. Tohoku J Exp Med, 2004, 204(3): 209-213. DOI: 10.1620/tjem.204.209.

4.Jousilahti P, Salomaa V, Hakala K, et al. The association of sensitive systemic inflammation markers with bronchial asthma[J]. Ann Allergy Asthma Immunol, 2002, 89(4): 381-385. DOI: 10.1016/S1081-1206(10)62039-X.

5.Ozseker F, Buyukozturk S, Depboylu B, et al. Serum amyloid A (SAA) in induced sputum of asthmatics: a new look to an old marker[J]. Int Immunopharmacol, 2006, 6(10): 1569-1576. DOI: 10.1016/j.intimp.2006.05.006.

6.Ricklefs I, Barkas I, Duvall MG, et al. ALX receptor ligands define a biochemical endotype for severe asthma[J]. JCI Insight, 2017, 2(14): e93534. DOI: 10.1172/jci.insight.93534.

7.Smole U, Kratzer B, Pickl WF. Soluble pattern recognition molecules: guardians and regulators of homeostasis at airway mucosal surfaces[J]. Eur J Immunol, 2020, 50(5): 624-642. DOI: 10.1002/eji.201847811.

8.Smole U, Gour N, Phelan J, et al. Serum amyloid A is a soluble pattern recognition receptor that drives type 2 immunity[J]. Nat Immunol, 2020, 21(7): 756-765. DOI: 10.1038/s41590-020-0698-1.

9.中华医学会变态反应分会呼吸过敏学组(筹),  中华医学会呼吸病学分会哮喘学组. 中国过敏性哮喘诊治指南(第一版, 2019年)[J]. 中华内科杂志, 2019, 58(9): 636-655. [Respiratory Allergy Group of Allergy Branch of Chinese Medical Association (Preparation), Asthma Group, Respiratory Branch of Chinese Medical Association. Chinese guidelines for the diagnosis and treatment of allergic asthma (2019, the first edition)[J]. Chinese Journal of Internal Medicine, 2019, 58(9): 636-655.] DOI: 10.3760/cma.j.issn.0578?1426.2019.09.004.

10.祝戎飞, 李文静, 王忠喜, 等. 武汉市气传花粉调查及与花粉症关系的研究[J]. 临床耳鼻咽喉头颈外科杂志, 2008, 22(14): 647-650. [Zhu RF, Li WJ, Wang ZX, et al. A survey of airborne pollen in Wuhan and its' relationship to pollinosis[J]. Journal of Clinical Otorhinolaryngology Head and Neck Surgery, 2008, 22(14): 647-650.] DOI: 10.3969/j.issn.1001-1781.2008.14.009.

11.Liu Q, Li Y, Yang F, et al. Distribution of serum amyloid A and establishment of reference intervals in healthy adults[J]. J Clin Lab Anal, 2020, 34(4): e23120. DOI: 10.1002/jcla.23120.

12.Breiteneder H, Peng Y Q, Agache I, et al. Biomarkers for diagnosis and prediction of therapy responses in allergic diseases and asthma[J]. Allergy, 2020, 75(12): 3039-3068.DOI: 10.1111/all.14582.

13.Akar-Ghibril N, Casale T, Custovic A, et al. Allergic endotypes and phenotypes of asthma[J]. J Allergy Clin Immunol Pract, 2020, 8(2): 429-440. DOI: 10.1016/j.jaip.2019.11.008.