Update on Nasal Polyps: Etiopathogenesis
Virat Kirtsreesakul MD*
Affiliation : * Division of Allergy and Rhinology, Department of Otolaryngology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla
Purpose of review: Nasal polyps is a common ENT disease with high medical failure and recurrence rate,
reflecting unknown pathogenesis. The present review is an update on the etiopathogenesis of nasal polyps.
Recent finding: Several mechanisms have been proposed for the formation of nasal polyps, including allergy,
mucosal allergy, autonomic imbalance, nitric oxide, superantigens, infection, abnormal transepithelial ion
transport, mucopolysaccharide abnormality, mechanical obstruction and epithelial rupture. Eosinophils
comprises more than 60% of the cell population. Activated T cells, mast cells and plasma cells are also
increased compared with the normal nasal mucosa. The stroma has numerous mediators, including cytokines,
growth factors, adhesion molecules, and immunoglobulins. Both Th1 and Th2 types of cytokines are upregulated
independent of the atopic status. An increased production of GM-CSF, IL5, RANTES and eotaxin can contrib-
ute to chronic eosinophilic inflammation by regulating the migration, survival and activation of eosinophils.
Conclusion : Nasal polyps is a multifactorial disease, with infectious, noninfectious, inflammation, anatomic
and genetic abnormalities. Chronic inflammation remains the central major factor in nasal polyps.
Keywords : Nasal polyps, Etiology, Pathogenesis, Histology
