Nasal cavity, paranasal sinuses, nasopharynx

Inflammatory lesions

Nasal polyps-inflammatory

Topic Completed: 1 November 2004

Minor changes: 15 February 2021

Copyright: 2004-2021,, Inc.

PubMed search: Nasal polyp[TI] inflammatory[TIAB]

Nat Pernick, M.D.
Page views in 2020: 20,354
Page views in 2021 to date: 20,898
Cite this page: Pernick, N. Nasal polyps-inflammatory. website. Accessed September 16th, 2021.
Definition / general
  • Most common type of nasal polyp
  • Due to recurrent attacks of rhinitis (allergic, inflammatory)
  • Most people with polyps are NOT atopic; only 0.5% with atopy develop polyps
  • Usually ages 30 years or older (rarely < age 20 years)
  • Often recurs after surgery
  • Often associated with asthma, chronic rhinitis, aspirin intolerance (14%)
Gross description
  • Usually multiple and bilateral and involve nasal cavity and paranasal sinuses
  • Have translucent, moist or edematous cut surface (opaque areas may represent papilloma)
  • Broad base of attachment is present
  • Usually not destructive
Microscopic (histologic) description
  • Respiratory epithelium, often with squamous metaplasia, edematous and loose stroma with hyperplastic mucous glands, inflammatory infiltrate (lymphocytes, plasma cells, eosinophils, neutrophils, mast cells)
  • Mucosa may be ulcerated or infected
  • Basal membrane may be thickened
  • May have bizarre stromal cells (large and pleomorphic) due to reactive changes
  • May have prominent glandular component
Differential diagnosis
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