BACKGROUND: Primary chronic rhinosinusitis (CRS) can be classified based on the sinuses involved and the dominant endotype of the mucosal inflammation. Since the introduction of type 2 targeted biologics as treatment option for CRS, assessment of the inflammatory status has gained importance in CRS patients. We here aimed to characterize CRS patients with and without elevated markers of type 2 inflammation. METHODS: CRS patients who visited the outpatient ENT clinic in one of the 10 tertiary centers in 7 European countries were invited to use the Galenus Health mobile application for the monitoring of their disease. RESULTS: CRS patients (n = 281) were stratified according to blood eosinophil counts or BEC (< 150 cells/μL: 21.6% of patients, ≥ 150 cells/μL: 78.4%; < 250 cells/μL: 36.3%, ≥ 250 cells/μL: 63.7%) and serum total IgE (< 100 IU/mL: 59.9%, ≥ 100 IU/mL: 40.1%). BEC and serum total IgE did not correlate well (Spearman r = 0.06; p = 0.39). CRS patients with BEC ≥ 150 cell/μL or ≥ 250 cells/μL, respectively, showed increased NPS, SNOT-22, VAS for total CRS symptoms, loss of smell, nasal blockage, runny nose compared to patients with BEC below 150 or 250 cells/μL. CRS patients with increased serum total IgE (≥ 100 IU/mL) did not show differences in the outcome parameters compared to patients with levels below 100 IU/mL. CRS patients with asthma (58.9%) showed increased SNOT-22 and VAS loss of smell compared to patients without asthma. CONCLUSIONS: A significant proportion of CRS patients exhibit a type 2 endotype, characterized by blood eosinophilia (78%), increased serum total IgE (40%) and/or concomitant asthma (59%). Our results underline the usefulness of eosinophils as a marker of type 2 inflammation and severity but challenge the utility of serum total IgE since it does not correlate with any of the markers of severity.

Allergy and Clinical Immunology Research Group Department of Microbiology Immunology and Transplantation KU Leuven Leuven Belgium

Clinic for ENT Diseases and Head and Neck Surgery University Clinic Münster Münster Germany

Department of Clinical Pharmacology and Pharmacology University of Groningen University Medical Center Groningen Groningen the Netherlands

Department of General ORL Head and Neck Surgery Medical University of Graz Graz Austria

Department of Neurosciences Experimental Otorhinolaryngology Rhinology Research KU Leuven Leuven Belgium

Department of Oral and Maxillofacial Sciences Sapienza University Rome Italy

Department of Otorhinolaryngology 1st Affiliated Hospital Sun Yat Sen University International Airway Research Center Guangzhou China

Department of Otorhinolaryngology and Head neck Surgery Amsterdam University Medical Centre University of Amsterdam Amsterdam the Netherlands

Department of Otorhinolaryngology Head and Neck Surgery Helsinki University Hospital and University of Helsinki Helsinki Finland

Department of Otorhinolaryngology Head and Neck Surgery UZ Leuven Leuven Belgium

Department of Otorhinolaryngology Head and Neck Surgery Vienna General Hospital Medical University of Vienna Vienna Austria

Department of Otorhinolaryngology Odense University Hospital Odense Denmark

Department of Otorhinolaryngology Universitätsklinikum Düsseldorf Dusseldorf Germany

Department of Respiratory Medicine 1st Faculty of Medicine Charles University and Thomayer Hospital Prague Czech Republic

Department of Rhinology Royal National Ear Nose Throat and Eastman Dental Hospital London UK

Department of Sense Organs Sapienza University Rome Italy

ENT Department Guy's and St Thomas' NHS Foundation Trust London UK

Galenus Health Hasselt Belgium

Otolaryngology Unit San Camillo Forlanini Hospital Rome Italy

Otorhinolaryngology Head and Neck Department Huriez Hospital Centre Hospitalier Universitaire Lille Lille France

Rhinology and Skull Base Surgery Unit Otorhinolaryngology Department Hospital Clinic IDIBAPS Ciberes Universitat de Barcelona Barcelona Spain

Service d'Otorhinolaryngologie Cliniques Universitaires Saint Luc Brussels Belgium

Zobrazit více v PubMed

Hastan D., Fokkens W. J., Bachert C., et al., “Chronic Rhinosinusitis in Europe‐‐An Underestimated Disease. A GA PubMed DOI

Jarvis D., Newson R., Lotvall J., et al., “Asthma in Adults and Its Association With Chronic Rhinosinusitis: The GA2LEN Survey in Europe,” Allergy 67, no. 1 (January 2012): 91–98, 10.1111/j.1398-9995.2011.02709.x. PubMed DOI

Bachert C., Bhattacharyya N., Desrosiers M., and Khan A. H., “Burden of Disease in Chronic Rhinosinusitis With Nasal Polyps,” Journal of Asthma and Allergy 14 (February 2021): 127–134, 10.2147/jaa.s290424. PubMed DOI PMC

Fokkens W. J., Lund V. J., Hopkins C., et al., “European Position Paper on Rhinosinusitis and Nasal Polyps 2020,” supplement, Journal of Rhinology 58, no. S29 (February 2020): 1–464, 10.4193/rhin20.600. PubMed DOI

Lourijsen E. S., Reitsma S., Vleming M., et al., “Endoscopic Sinus Surgery With Medical Therapy Versus Medical Therapy for Chronic Rhinosinusitis With Nasal Polyps: A Multicentre, Randomised, Controlled Trial,” Lancet Respiratory Medicine 10, no. 4 (January 2020): 337–346, 10.1016/s2213-2600(21)00457-4. PubMed DOI

Calus L., Van Bruaene N., Bosteels C., et al., “Twelve‐Year Follow‐Up Study After Endoscopic Sinus Surgery in Patients With Chronic Rhinosinusitis With Nasal Polyposis,” Clinical and Translational Allergy 9, no. 1 (2019): 30, 10.1186/s13601-019-0269-4. PubMed DOI PMC

Cavaliere C., Masieri S., Begvarfaj E., et al., “Long‐Term Perspectives on Chronic Rhinosinusitis With Nasal Polyps: Evaluating Recurrence Rates After Functional Endoscopic Sinus Surgery in the Biologics Era—A 5‐Year Follow‐Up Study,” Journal of Personalized Medicine 14, no. 3 (March 2024): 297, 10.3390/jpm14030297. PubMed DOI PMC

van der Veen J., Seys S. F., Timmermans M., et al., “Real‐Life Study Showing Uncontrolled Rhinosinusitis After Sinus Surgery in a Tertiary Referral Centre,” Allergy 72, no. 2 (February 2017): 282–290, 10.1111/all.12983. PubMed DOI PMC

Toppila‐Salmi S., Lyly A., Simin J., Aakko J., Olsen H. H., and Lehtimäki L., “Predictors of Revision Endoscopic Sinus Surgery in Finnish Patients With Chronic Rhinosinusitis With Nasal Polyps,” Clinical and Translational Allergy 15, no. 2 (2025): e70032, 10.1002/clt2.70032. PubMed DOI PMC

Bachert C., Marple B., Hosemann W., Cavaliere C., Wen W., and Zhang N., “Endotypes of Chronic Rhinosinusitis With Nasal Polyps: Pathology and Possible Therapeutic Implications,” Journal of Allergy and Clinical Immunology: In Practice 8, no. 5 (May 2020): 1514–1519, 10.1016/j.jaip.2020.03.007. PubMed DOI

De Greve G., Hellings P. W., Fokkens W. J., Pugin B., Steelant B., and Seys S. F., “Endotype‐Driven Treatment in Chronic Upper Airway Diseases,” Clinical and Translational Allergy 7, no. 1 (2017): 22, 10.1186/s13601-017-0157-8. PubMed DOI PMC

Bogaert S., Rheindorf E., Dazert S., et al., “Quality of Life in Type 2 and Non‐Type 2 Endotypes in Chronic Rhinosinusitis With Nasal Polyps: A Prospective Trial,” Clinical and Translational Allergy 15, no. 6 (2025): e70070, 10.1002/clt2.70070. PubMed DOI PMC

Stevens W. W., Peters A. T., Tan B. K., et al., “Associations Between Inflammatory Endotypes and Clinical Presentations in Chronic Rhinosinusitis,” Journal of Allergy and Clinical Immunology: In Practice 7, no. 8 (2019): 2812–2820.e3, 10.1016/j.jaip.2019.05.009. PubMed DOI PMC

Laidlaw T. M., Mullol J., Woessner K. M., Amin N., and Mannent L. P., “Chronic Rhinosinusitis With Nasal Polyps and Asthma,” Journal of Allergy and Clinical Immunology: In Practice 9, no. 3 (March 2021): 1133–1141, 10.1016/j.jaip.2020.09.063. PubMed DOI

Murtomäki A., Helevä A., Torkki P., et al., “Comorbidities of Chronic Rhinosinusitis in Children and Adults,” Clinical and Translational Allergy 14, no. 4 (2024): e12354, 10.1002/clt2.12354. PubMed DOI PMC

Papacharalampous G. X., Constantinidis J., Fotiadis G., Zhang N., Bachert C., and Katotomichelakis M., “Chronic Rhinosinusitis With Nasal Polyps (CRSwNP) Treated With Omalizumab, Dupilumab, or Mepolizumab: A Systematic Review of the Current Knowledge Towards an Attempt to Compare Agents’ Efficacy,” International Forum of Allergy & Rhinology 14, no. 1 (2024): 96–109, 10.1002/alr.23234. PubMed DOI

Striz I., Golebski K., Strizova Z., et al., “New Insights Into the Pathophysiology and Therapeutic Targets of Asthma and Comorbid Chronic Rhinosinusitis With or Without Nasal Polyposis,” Clinical science (London, England: 1979) 137, no. 9 (May 2023): 727–753, 10.1042/cs20190281. PubMed DOI PMC

Bachert C., Han J. K., Desrosiers M., et al., “Efficacy and Safety of Dupilumab in Patients With Severe Chronic Rhinosinusitis With Nasal Polyps (LIBERTY NP SINUS‐24 and LIBERTY NP SINUS‐52): Results From Two Multicentre, Randomised, Double‐Blind, Placebo‐Controlled, Parallel‐Group Phase 3 Trials,” Lancet 394, no. 10209 (September 2019): 1638–1650, 10.1016/s0140-6736(19)31881-1. PubMed DOI

Gevaert P., Omachi T. A., Corren J., et al., “Efficacy and Safety of Omalizumab in Nasal Polyposis: 2 Randomized Phase 3 Trials,” Journal of Allergy and Clinical Immunology 146, no. 3 (September 2020): 595–605, 10.1016/j.jaci.2020.05.032. PubMed DOI

Han J. K., Bachert C., Fokkens W., et al., “Mepolizumab for Chronic Rhinosinusitis With Nasal Polyps (SYNAPSE): A Randomised, Double‐Blind, Placebo‐Controlled, Phase 3 Trial,” Lancet Respiratory Medicine 9, no. 10 (October 2021): 1141–1153, 10.1016/s2213-2600(21)00097-7. PubMed DOI

Seys S. F., Schneider S., Kinderen J. de, et al., and CHRINOSOR Consortium , “Real‐World Effectiveness of Dupilumab in a European Cohort of Chronic Rhinosinusitis With Nasal Polyps (CHRINOSOR),” Journal of Allergy and Clinical Immunology 155, no. 2 (Febr 2025): 451–460, 10.1016/j.jaci.2024.10.016. PubMed DOI

Cavaliere C., Loperfido A., Ciofalo A., et al., “Real‐Life Evidence of Mepolizumab Treatment in Chronic Rhinosinusitis With Nasal Polyps: A Multicentric Study,” Journal of Clinical Medicine 13, no. 12 (June 2024): 3575, 10.3390/jcm13123575. PubMed DOI PMC

Lombardo N., Piazzetta G. L., Lobello N., et al., “Real‐Life Effects of Omalizumab on Chronic Rhinosinusitis With Nasal Polyposis,” Journal of Personalized Medicine 14, no. 1 (December 2023): 3, 10.3390/jpm14010003. PubMed DOI PMC

Hopkins C., Han J. K., Fokkens W., et al., “Dupilumab Versus Mepolizumab for Chronic Rhinosinusitis With Nasal Polyposis: An Indirect Treatment Comparison,” Journal of Allergy and Clinical Immunology: In Practice 12, no. 12 (December 2024): 3393–3401.e15, 10.1016/j.jaip.2024.09.015. PubMed DOI

Rogers L., Jesenak M., Bjermer L., Hanania N. A., Seys S. F., and Diamant Z., “Biologics in Severe Asthma: A Pragmatic Approach for Choosing the Right Treatment for the Right Patient,” Respiratory Medicine, [Internet] 218 (November 2023): 107414 [cited 2024 Nov 5], https://www.resmedjournal.com/article/S0954‐6111(23)00302‐5/fulltext#fig1. PubMed

Seys S. F., Bousquet J., Bachert C., et al., “mySinusitisCoach: Patient Empowerment in Chronic Rhinosinusitis Using Mobile Technology,” Rhinology International Journal 56, no. 3 (2018): 209–215 (in press), 10.4193/rhin17.253. PubMed DOI

Seys S. F., De Bont S., Fokkens W. J., et al., “Real‐Life Assessment of Chronic Rhinosinusitis Patients Using Mobile Technology: The mySinusitisCoach Project by EUFOREA,” Allergy 75, no. 11 (November 2020): 2867–2878, 10.1111/all.14408. PubMed DOI PMC

Urdova V., Rogers L., Jesenak M., and Seys S. F., “Real‐Life Studies and Registries of Severe Asthma: The Advent of Digital Technology,” Respiratory Medicine, [Internet] 220 (December 2023): 107429 [cited 2024 Dec 5], https://www.resmedjournal.com/article/S0954‐6111(23)00317‐7/fulltext. PubMed

Seys S. F., Hellings P. W., Alobid I., et al., “Chronic Rhinosinusitis Outcome Registry (CHRINOSOR): Establishment of an International Outcome Registry Driven by mHealth Technology,” Journal of Allergy and Clinical Immunology: In Practice 11, no. 2 (February 2023): 431–438.e2, 10.1016/j.jaip.2022.09.043. PubMed DOI

Bachert C., Han J. K., Wagenmann M., et al., “EUFOREA Expert Board Meeting on Uncontrolled Severe Chronic Rhinosinusitis With Nasal Polyps (CRSwNP) and Biologics: Definitions and Management,” Journal of Allergy and Clinical Immunology 147, no. 1 (January 2021): 29–36, 10.1016/j.jaci.2020.11.013. PubMed DOI

Dekeyser A., Huart C., Hummel T., and Hox V., “Olfactory Loss in Rhinosinusitis: Mechanisms of Loss and Recovery,” International Journal of Molecular Sciences 25, no. 8 (January 2024): 4460, 10.3390/ijms25084460. PubMed DOI PMC

Marin C., Alobid I., López‐Chacón M., VanStrahlen C. R., and Mullol J., “Type 2 and Non‐type 2 Inflammation in the Upper Airways: Cellular and Molecular Alterations in Olfactory Neuroepithelium Cell Populations,” Current Allergy and Asthma Reports 24, no. 4 (April 2024): 211–219, 10.1007/s11882-024-01137-x. PubMed DOI PMC

Lavin J., Min J. Y., Lidder A. K., et al., “Superior Turbinate Eosinophilia Correlates With Olfactory Deficit in Chronic Rhinosinusitis Patients,” Laryngoscope 127, no. 10 (2017): 2210–2218, 10.1002/lary.26555. PubMed DOI PMC

Alobid I., Calvo‐Henríquez C., Viveros‐Díez P., et al., “Validation of Visual Analogue Scale for Loss of Smell as a Quick Test in Chronic Rhinosinusitis With Nasal Polyps,” Journal of Investigational Allergology and Clinical Immunology, [Internet] 34, no. 6 (September 2023): [cited 2024 Nov 29], https://www.jiaci.org/ahead‐of‐print/validation‐of‐visual‐analogue‐scale‐for‐loss‐of‐smell‐as‐a‐quick‐test‐in‐chronic‐rhinosinusitis‐with‐nasal‐polyps. PubMed

Otten J. J., van der Lans R. J. L., Elzinga H. B. E., et al., “More Than Half of Chronic Rhinosinusitis With Nasal Polyps (CRSwNP) Patients Treated With Dupilumab Experience Early and Fast Olfactory Improvement Within 28 Days,” Allergy 79, no. 11 (2024): 3166–3168, 10.1111/all.16357. PubMed DOI

Fokkens W. J., Lund V. J., Mullol J., et al., “European Position Paper on Rhinosinusitis and Nasal Polyps 2012,” Rhinology ‐ Supplement 23, no. 3 (March 2012): p preceding table of contents, 1–298. 10.4193/Rhino12.000. PubMed DOI

Tomassen P., Vandeplas G., Van Zele T., et al., “Inflammatory Endotypes of Chronic Rhinosinusitis Based on Cluster Analysis of Biomarkers,” Journal of Allergy and Clinical Immunology 137, no. 5 (May 2016): 1449–1456.e4, 10.1016/j.jaci.2015.12.1324. PubMed DOI

Lou H., Meng Y., Piao Y., Wang C., Zhang L., and Bachert C., “Predictive Significance of Tissue Eosinophilia for Nasal Polyp Recurrence in the Chinese Population,” American Journal of Rhinology & Allergy 29, no. 5 (September 2015): 350–356, 10.2500/ajra.2015.29.4231. PubMed DOI

Bhattacharyya N., Vyas D. K., Fechner F. P., Gliklich R. E., and Metson R., “Tissue Eosinophilia in Chronic Sinusitis: Quantification Techniques,” Archives of Otorhinolaryngology‐Head & Neck Surgery 127, no. 9 (September 2001): 1102–1105, 10.1001/archotol.127.9.1102. PubMed DOI

Lou H., Zhang N., Bachert C., and Zhang L., “Highlights of Eosinophilic Chronic Rhinosinusitis With Nasal Polyps in Definition, Prognosis, and Advancement,” International Forum of Allergy & Rhinology 8, no. 11 (2018): 1218–1225, 10.1002/alr.22214. PubMed DOI PMC

Tosun F., Arslan H. H., Karslioglu Y., Deveci M. S., and Durmaz A., “Relationship Between Postoperative Recurrence Rate and Eosinophil Density of Nasal Polyps,” Annals of Otology, Rhinology & Laryngology 119, no. 7 (July 2010): 455–459, 10.1177/000348941011900705. PubMed DOI

Bachert C., Gevaert P., and Van Cauwenberge P., “ PubMed DOI

Gevaert P., Wong K., Millette L. A., and Carr T. F., “The Role of IgE in Upper and Lower Airway Disease: More Than Just Allergy!,” Clinical Reviews in Allergy and Immunology 62, no. 1 (2022): 200–215, 10.1007/s12016-021-08901-1. PubMed DOI PMC

Jesenak M., Diamant Z., Simon D., et al., “Eosinophils‐From Cradle to Grave: An EAACI Task Force Paper on New Molecular Insights and Clinical Functions of Eosinophils and the Clinical Effects of Targeted Eosinophil Depletion,” Allergy 78, no. 12 (December 2023): 3077–3102, 10.1111/all.15884. PubMed DOI

Diamant Z., Vijverberg S., Alving K., et al., “Toward Clinically Applicable Biomarkers for Asthma: An EAACI Position Paper,” Allergy 74, no. 10 (October 2019): 1835–1851, 10.1111/all.13806. PubMed DOI

Seys S. F. and Long M. B., “The Quest for Biomarkers in Asthma: Challenging the T2 Versus non‐T2 Paradigm,” European Respiratory Journal 59, no. 2 (February 2022): 2102669, 10.1183/13993003.02669-2021. PubMed DOI

Fokkens W. J., Viskens A. S., Backer V., et al., “EPOS/EUFOREA Update on Indication and Evaluation of Biologics in Chronic Rhinosinusitis With Nasal Polyps 2023,” Rhinology 61, no. 3 (June 2023): 194–202, 10.4193/Rhin22.489. PubMed DOI

Casciano J., Krishnan J. A., Small M. B., et al., “Value of Peripheral Blood Eosinophil Markers to Predict Severity of Asthma,” BMC Pulmonary Medicine 16, no. 1 (July 2016): 109, 10.1186/s12890-016-0271-8. PubMed DOI PMC

De Schryver E., Devuyst L., Derycke L., et al., “Local Immunoglobulin E in the Nasal Mucosa: Clinical Implications,” Allergy, Asthma & Immunology Research 7, no. 4 (July 2015): 321–331, 10.4168/aair.2015.7.4.321. PubMed DOI PMC

van der Lans R., Otten J., Adriaensen G. F. J. P. M., et al., “Eosinophils Are the Dominant Type2 Marker for the Current Indication of Biological Treatment in Severe Uncontrolled Chronic Rhinosinusitis With Nasal Polyps,” Rhinology 62, no. 3 (2024): 383–384, 10.4193/Rhin23.081. PubMed DOI