Histopathology of Allergic Fungal Rhinosinusitis Versus Chronic Rhinosinusitis with Nasal Polyps

Tamara Simpson; Vidit Talati; Ali M Baird; Paolo Gattuso; Mary K Allen-Proctor; Peter Papagiannopoulos; Pete S Batra; Peter Filip; Bobby A Tajudeen

doi:10.1002/lary.31225

Histopathology of Allergic Fungal Rhinosinusitis Versus Chronic Rhinosinusitis with Nasal Polyps

Laryngoscope. 2023 Dec 10. doi: 10.1002/lary.31225. Online ahead of print.

Authors

Tamara Simpson¹, Vidit Talati², Ali M Baird¹, Paolo Gattuso³, Mary K Allen-Proctor³, Peter Papagiannopoulos², Pete S Batra², Peter Filip², Bobby A Tajudeen²

Affiliations

¹ Rush Medical College, Rush University Medical Center, Chicago, Illinois, U.S.A.
² Department of Otorhinolaryngology-Head and Neck Surgery and Rush Sinus, Allergy, and Asthma Center, Rush University Medical Center, Chicago, Illinois, U.S.A.
³ Department of Pathology, Rush University Medical Center, Chicago, Illinois, U.S.A.

PMID: 38073117
DOI: 10.1002/lary.31225

Abstract

Objective: Structured histopathology (SHP) is a method of analyzing sinonasal tissue to characterize endotypes of chronic rhinosinusitis with nasal polyps (CRSwNP). Allergic fungal rhinosinusitis (AFRS) shares several features with certain endotypes of CRSwNP. Our objective was to compare the histopathology of AFRS and eosinophilic CRSwNP to further understand whether they are separate endotypes or disease entities altogether.

Methods: A retrospective review of AFRS and CRSwNP patients undergoing endoscopic sinus surgery was performed. Data were collected on demographics, comorbidities, subjective and objective severity scores, and 13-variable SHP reports. CRSwNP patients with >10 eosinophils per high-power field (eCRSwNP) were included. Chi-squared and t-tests were used for statistical analysis.

Results: A total of 29 AFRS and 108 eCRSwNP patients were identified. AFRS patients were younger and more often Black. Symptom severity scores (SNOT-22, Lund-MacKay, and Lund-Kennedy) were uniform between groups. AFRS patients had a higher rate of Charcot-Leyden crystals (41.4% vs. 10.2%; p < 0.001). Severe degree of inflammation, eosinophilic inflammatory predominance, eosinophil aggregates, subepithelial edema, and basement membrane thickening were common in both groups, and their rates were not statistically significantly different between groups. Metaplasia, ulceration, fibrosis, and hyperplastic/papillary change rates were low (<30%) and similar between groups.

Conclusion: The SHP of eCRSwNP and AFRS are highly consistent, which suggests AFRS is a severe subtype of CRSwNP overall rather than a separate disease entity. This also lends credence to AFRS belonging on the endotypic spectrum of CRSwNP.

Level of evidence: 3 Laryngoscope, 2023.

Keywords: adult rhinology; allergic fungal rhinosinusitis; allergy/rhinology; chronic rhinosinusitis; endotype; immunology; nasal polyposis; structured histopathology.