Relevance of Th2 markers in the assessment and therapeutic management of severe allergic asthma: a real life perspective
Caminati M1, Vianello A2, Chieco Bianchi F2, Festi G3, Guarnieri G4, Marchi MR2, Micheletto C5, Olivieri M6, Tognella S7, Guerriero M8, Senna G1, on behalf of NEONET Study Group*
1Asthma Center and Allergy Unit, Verona University Hospital, Verona, Italy.
2Respiratory Pathophysiology Division, University-City Hospital of Padua, Padua, Italy.
3Pulmonary Unit, Verona University Hospital, Verona, Italy
4Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Padua, Italy
5Respiratory Unit, Mater Salutis Hospital, Legnago, Verona, Italy
6Unit of Occupational Medicine, Verona University Hospital, Verona, Italy.
7Respiratory Unit, Orlandi General Hospital, Bussolengo, Verona, Italy
8Department of Computer Science, University of Verona, Verona, Italy.
*Denise Artioli, Elisabetta Bertocco, Lucio Bonazza, Mariangiola Crivellaro, Fabio De Conti, Annarita Dama, Giulio Donazzan, Giuseppe Idotta, Carlo Lombardi, Luigi Marino, Francesco Mazza, Stefano Nardini, Federico Reccardini, Michele Schiappoli.
J Investig Allergol Clin Immunol 2020; Vol. 30(1)
Background: Although blood eosinophils are currently recognized as the main clinical marker of Th2 inflammation, their relevance in identifying asthma severity is still matter of debate.
Methods: Our retrospective real-life study on severe asthmatics included in the NEONet Italian database, aimed at investigating the relevance of blood eosinophil count and FeNO in severe asthma clinical assessment and their role as a potential predictor of responsiveness to anti-IgE therapy. As cut-off values 300 blood eosinophils/mm3 and 30 ppm for FeNO were chosen.
Results: Overall 132 adult patients were evaluated. No significant differences could be observed between the high and low basal eosinophils groups, in terms of demographic data, total IgE, lung function, Patient Reported Outcomes (PROs), nasal comorbidities. The patients with FeNO > 30 ppb showed a worse ACT score, and a lower AQLQ score in comparison with the FeNO< 30 ppb ones. In the high FeNO subgroup, more frequent hospital admissions and a higher number of lost working days in the last year were registered. A combined score including both eosinophils and FeNO did not to improve the accuracy of the single parameters. In the high eosinophil subgroup the proportion of responders to omalizumab treatment was greater and increased at every follow-up time point.
Conclusions: According to our findings blood eosinophils do not represent a univocal marker of asthma severity, whilst a higher FeNO level is associated with more frequent hospital admissions and lost working days. Blood eosinophils seem to act as predictor of treatment responsiveness to omalizumab.
Key words: Severe Asthma, Eosinophils, Omalizumab, Biomarker, Th2 Inflammation, Asthma Network