Nasal polyps—benign growths in the nasal cavity—are common among people with chronic rhinosinusitis and asthma. It is estimated that 2.1% of US adults have chronic rhinosinusitis, and of those, about 25% to 30% have nasal polyps.¹ Moreover, of those with chronic rhinosinusitis with nasal polyps, an estimated 26% to 56% also have asthma.² Some of these patients may also develop aspirin-exacerbated respiratory disease, or Samter’s triad.³ Because of this, patients with chronic rhinosinusitis with nasal polyps have significant morbidity and decreased quality of life.⁴ Therefore, it is critical to screen for, diagnose, and treat chronic rhinosinusitis with nasal polyps.

The exact etiology of nasal polyps is unknown. However, research suggests that bacteria, fungi, allergens, and superantigens can contribute to the pathophysiology of chronic rhinosinusitis with nasal polyps.⁵ The breakdown of epithelial membrane in the nasal passages over time leads to increased permeability of viruses, bacteria, and fungi.^1,4

It is well known that chronic inflammation contributes to the development of nasal polyps. A new study examined the role of necroptosis—an inflammatory cell death—among patients with chronic rhinosinusitis with nasal polyps.⁶ The researchers found that necroptosis induced by tumor necrosis factor α and interferon γ may be associated with neutrophilic inflammation in chronic rhinosinusitis with nasal polyps. Other immune-related pathways studied include T-helper 2, immunoglobulin-E, and interleukin 5, 6, and 13.^1,4,5

A recent study investigated the role of IL-6 in the pathogenesis of chronic rhinosinusitis with nasal polyps.¹⁹ The investigators found that IL-6 regulates the function of Th17/Treg cells, which means the Th17/Treg cells may be a new treatment pathway.¹⁹

Genetic factors might also contribute to the development of, or protection from, development of nasal polyps. Results from a recent study showed that ALOX15 significantly protects against nasal polyps in patients in Iceland and the United Kingdom.⁷ The researchers also found 10 markers associated with nasal polyps that may help target treatment options.⁷

The differential diagnosis of nasal polyps is various and can include antrochoanal polyps, inverted papillomas, nasal duct cysts, nasal gliomas, and hemangiomas, among others.¹ Typically, benign nasal polyps associated with chronic rhinosinusitis form in both nasal passages, whereas malignant polyps are typically found only on one side.⁴

To narrow the diagnosis, the American Academy of Otolaryngology and the American Academy of Family Practice recommend conducting a thorough physical examination and gathering a focused sinonasal history.⁸ Chronic rhinosinusitis is categorized as the presence of at least 2 of the 4 cardinal symptoms for at least 12 consecutive weeks. The cardinal symptoms include facial pain or pressure, hyposmia or anosmia, nasal drainage, and nasal obstruction.⁸

Conducting a nasal endoscopic examination is one screening tool to evaluate for polyps in the office.² Computed tomography (CT) scanning of the sinuses is also recommended by the American Academy of Otolaryngology and the American Academy of Family Practice.⁸ Specifically:

• - Obtain scans axially with no (zero-degree) gantry tilt.
• - Include all of the forehead and extend to the maxillary teeth, also including the ears and tip of the nose.
• - Maintain a maximum slice thickness of 1 mm.
• - Get contiguous, nonoverlapping slices.
• - Save in an uncompressed DICOM format.

Nasal polyps can be managed via medical therapy or surgical therapy to reduce symptoms and improve breathing and quality of life. The Sinonasal Outcome Test-22 (SNOT-22) can help track quality of life scores in the nasal, ear/facial, sleep, function, and emotion domains.⁹

Nasal saline irrigation and intranasal corticosteroid sprays are considered first-line therapies.⁸ Courses of oral corticosteroids alone or as an adjunct to standard maintenance therapy may also be prescribed for up to 3 weeks.^8,10 New research has shown that dd-on mepolizumab therapy can improve endoscopic nasal polyp scores and nasal obstruction visual analogue scale scores.¹⁶ Antibiotics may also be appropriate if an active acute sinus infection is evident.⁸

For patients with chronic rhinosinusitis with nasal polyps and asthma, omalizumab has been shown to reduce congestion, SNOT-22 score, and total symptom score, regardless of aspirin sensitivity.¹¹ Fluticasone can also help improve sense of smell, quality of life scores, and endoscopic evaluation of polyp grade.¹² Recent research has also investigated the use of biologics for treating chronic rhinosinusitis with nasal polyps.^13,14

Patients who fail medical therapy should be referred to an otolaryngologist, allergist, or pulmonologist, and endoscopic sinus surgery may be warranted.⁸

Although adherence to intranasal corticosteroids is generally low in patients with chronic rhinosinusitis and nasal polyps¹⁷, recent research shows that intranasal budesonide and saline irrigations can reduce SNOT-22 scores after only a few months of use.¹⁸

Even after surgical intervention, the risk of recurrence is high among patients with nasal polyps. To better predict whether nasal polyps will recur, researchers in China developed a nomogram and evaluated patients preoperatively and 3 years post-surgery.¹⁵ Ultimately, they found that the nomogram had a recurrence-predicting C index of 0.81 in the training cohort (patients who had undergone surgery in a previous period) and of 0.80 in the validation cohort (patients who had undergone surgery during the study period).¹⁵

Chronic rhinosinusitis with nasal polyps is a common health condition in the United States and is treatable with medical and surgical therapy. Because of the risk of morbidity, early diagnosis and treatment is critical for the most optimal patient outcomes.

1. del Toro E, Portela J. Nasal polyps. In: StatPearls. StatPearls Publishing; August 6, 2021. http://www.ncbi.nlm.nih.gov/books/nbk560746/

2. Moore A. Nasal polyps. American Academy of Allergy, Asthma & Immunology. Reviewed June 28, 2019. Accessed September 2, 2021. https://www.aaaai.org/Tools-for-the-Public/Conditions-Library/Allergies/Nasal-Polyps

3. Moore A. Aspirin-Exacerbated Respiratory Disease. American Academy of Allergy, Asthma & Immunology. Reviewed September 28, 2020. Accessed September 2, 2021. https://www.aaaai.org/Tools-for-the-Public/Conditions-Library/Asthma/Aspirin-Exacerbated-Respiratory-Disease-(AERD)

4. Stevens WW, Schleimer RP, Kern RC. Chronic rhinosinusitis with nasal polyps. J Allergy Clin Immunol Pract. 2016;4(4):565-572. https://dx.doi.org/10.1016%2Fj.jaip.2016.04.012

5. Chaaban MR, Walsh EM, Woodworth BA. Epidemiology and differential diagnosis of nasal polyps. Am J Rhinol Allergy. 2013;27(6):473-478. https://dx.doi.org/10.2500%2Fajra.2013.27.3981

6. Xie Y, Li M, Chen K, et al. Necroptosis underlies neutrophilic inflammation associated with the chronic rhinosinusitis with nasal polyps (CRSwNP). J Inflamm Res. Published online August 16, 2021. https://doi.org/10.2147/jir.s322875

7. Kristjansson RP, Benonisdottir S, Davidsson OB, et al. A loss-of-function variant in ALOX15 protects against nasal polyps and chronic rhinosinusitis. Nat Genet. 2019;51(2):267-276. https://doi.org/10.1038/s41588-018-0314-6

8. Sedaghat AR. Chronic rhinosinusitis. Am Fam Physician. 2017;96(8):500-506. https://www.aafp.org/afp/2017/1015/p500.html

9. Khan AH, Reaney M, Guillemin I, et al. Development of Sinonasal Outcome Test (SNOT-22) domains in chronic rhinosinusitis with nasal polyps. Laryngoscope. 2021;10.1002/lary.29766. https://doi.org/10.1002/lary.29766

10. Radajewski K, Kalińczak-Górna P, Zdrenka M, et al. Short term pre-operative oral corticosteroids-tissue remodeling in chronic rhinosinusitis with nasal polyps. J Clin Med. 2021;10(15):3346. https://doi.org/10.3390/jcm10153346

11. Damask C, Chen M, Holweg CTJ, Yoo B, Millette LA, Franzese C. Defining the efficacy of omalizumab in nasal polyposis: a POLYP 1 and POLYP 2 subgroup analysis. Am J Rhinol Allergy. Published online August 12, 2021. https://doi.org/10.1177/19458924211030486

12. Wu D, Huang T, Wei Y. Effects of fluticasone exhalation delivery system in patients with chronic rhinosinusitis with nasal polyps: a systematic review. Am J Rhinol Allergy. Published online August 3, 2021. https://doi.org/10.1177/19458924211033214

13. Nolasco S, Crimi C, Pelaia C, et al. Benralizumab effectiveness in severe eosinophilic asthma with and without chronic rhinosinusitis with nasal polyps: a real-world multicentre study. J Allergy Clin Immunol Pract. Published online August 19, 2021. https://doi.org/10.1016/j.jaip.2021.08.004

14. Lipworth BJ, Chan R. The choice of biologics in patients with severe chronic rhinosinusitis with nasal polyps. J Allergy Clin Immunol Pract. Published online July 28, 2021. https://doi.org/10.1016/j.jaip.2021.07.023

15. Du K, Zheng M, Zhao Y, et al. A nomogram combing peripheral parameter for estimation of CRSwNP recurrence. Am J Rhinol Allergy. 2021;35(5):578-586. https://doi.org/10.1177/194589242097895 

16. Han JK, Bachert C, Fokkens W, et al. Mepolizumab for chronic rhinosinusitis with nasal polyps (SYNAPSE): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet Respir Med. 2021;9(10):1141-1153. https://doi.org/10.1016/s2213-2600(21)00097- 

17. Valverde-Monge M, Barroso B, Ortega-Martin L, et al. Exploring adherence to treatment in nasal polyposis. J Investig Allergol Clin Immunol. Published online ahead of print: September 3, 2021. https://doi.org/10.18176/jiaci.0752 

18. Talat R, Gengler I, Phillips KM, Caradonna DS, Gray ST, Sedaghat AR. Chronic rhinosinusitis outcomes of patients with aspirin-exacerbated respiratory disease treated with budesonide irrigations: a case series. Ann Otol Rhinol Laryngol. Published online November 14, 2021. https://doi.org/10.1177/00034894211054948