Nasal Polyps

Nasal polyps are lesions arising from the nasal mucosa, occurring at any site in the nasal cavity or paranasal sinuses but most frequently seen in the clefts of the middle meatus. Histological examination reveals that in 85%-90% of cases, these are sac-like entities with an eosinophil-rich oedematous wall characterised by goblet cell hyperplasia and a thick basement membrane; their poor blood supply gives them a pale appearance. They may be single or multiple and small or very large. The exact pathogenesis is not known but they have been linked with chronic infection and inflammation (such as in chronic rhinosinusitis), allergy, autonomic nerve dysfunction and possibly an element of genetic predisposition.¹ Nasal polyps can co-exist with both benign and malignant intra-nasal tumours.

Incidence and prevalence

• There is a 1-20 in 1000 chance of developing nasal polyps in a normal person (declining after the age of 60).
• The occurrence in the normal population is 0.1% in children and about 1% in adults.
• There is a gender difference; 2-4 males:1 female.
• There is no racial predilection.

Associations

• Infective sinusitis: Streptococcus pneumoniae, Staphylococcus aureus, Bacteroides fragilis (all common pathogens in sinusitis) and Pseudomonas aeruginosa have all been seen in association with polyp formation.
• Cystic fibrosis (CF): children aged 16 years or younger presenting with nasal polyps should be considered to have CF until proven otherwise. Nasal polyps are found in 3-48% of CF patients. P.aeruginosa is more commonly seen in these patients.
• Asthma: multiple benign polyps may be seen in 20-50% of these patients. Different categories of asthmatic adult patients are associated with different frequencies of nasal polyposis: 13% (non-allergic), 8% (with aspirin intolerance: Samter's Triad - most aggressive form of the disease, see below) and 5% (atopy).
• Fungal sinusitis: 80% of these patients have nasal polyps. It is rare in the UK but more common in warmer areas (e.g. southern USA and Australia).³
• Kartagener's syndrome: 27% of these patients have nasal polyps.
• Other disease associations include Churg-Strauss syndrome, non-allergic rhinitis with eosinophilia syndrome (NARES), Young syndrome, primary ciliary dyskinesia, alcohol intolerance.

Symptoms

This depends on the size of the polyp: small polyps may be asymptomatic. Symptoms include:

• Nasal airway obstruction
• Watery anterior rhinorrhoea, sneezing, postnasal drainage
• Dull headaches
• Snoring and obstructive sleep symptoms
• Hyposmia or anosmia (decreased smell)
• Decreased taste
• Chronic mouth breathing
• Change in the quality of their voice

These patients may have a history of recurring acute or chronic sinusitis.¹ Occasionally, massive polyps can give rise to craniofacial structural abnormalities leading to proptosis, hypertelorism (increased interorbital distance) and diplopia.³ Some may grow into the cranial cavity but they rarely cause neurological signs as their growth is very slow.

Examination

• Using an aural speculum, look for single or clusters of grape-like structures. Very large polyps may grow down into the oropharynx and can be visualised with a tongue depressor.
• Decongestants and local anaesthesia may help examination.
• Polyps may be (i) confined to the middle meatus, (ii) extend beyond the middle meatus but not completely obstruct the airway or (iii) completely obstruct the airway.
• Associated green-brown secretion is suggestive of a fungal infection.

• Sinusitis
• Encephalocoele
• Glioma
• Dermoid tumour
• Haemangioma
• Papilloma
• Juvenile nasopharyngeal glioma
• Rhabdomyosarcoma
• Lymphoma
• Blastoma
• Neurosarcoma
• Nasopharyngeal carcinoma

• A nasal speculum will allow visualisation up until the anterior edge of the middle turbinate (in good conditions!). Misting of the speculum helps confirm good airflow.
• A nasal smear or brushing can be carried out to detect eosinophils.
• Rigid or flexible endoscopy (rhinoscopy) carried out by specialists: this is the best way to visualise the nasal cavity and oropharynx. It allows localisation and determination of the extent of the polyps but is distressing for the young child.
• Plain X-Ray films are of limited value: they may show generalised opacification of the paranasal sinuses but yield little other information. They are not generally recommended.⁴
• CT scan (thin cut, of the maxillofacial area): further involvement of the sinuses can be assessed and these images will guide any surgical intervention.³
• MRI scanning may be carried out if intracranial growth is suspected.

General principles

• Once diagnosis established, refer the patient to an ENT team for a full examination and work-up. This is especially important with unilateral polyps which may be a sign of malignancy.
• Review patient for the presence of associated diseases such as covert asthma and in severe cases, explore the possibility of aspirin sensitivity, especially if this is associated with asthma.
• Children should be referred to rule out the presence of a meningocoele and to test for CF.⁵
• As there is no single causative factor, treatment targets the underlying inflammatory process in the first instance with surgery being a subsequent option if symptoms are not under control.
• The aims of treatment are to relieve obstruction, restore olfaction, improve sinus drainage and to relieve accompanying symptoms.
• Patients should be educated regarding the recurring nature of this problem.

Drugs

All patients should have a trial of medical treatment before consideration for surgery. A medical polypoidectomy refers to the steroid regimen used to treat large polyps (see below). Corticosteroid therapy remains the mainstay of medical management. Polyps respond in up to 80% of cases⁶ with a reduction in size, improvement in associated symptoms and reduction in recurrence post surgical removal. However, these drugs do not address the problems of hyposmia.

• Topical corticosteroids: there are a range of topical corticosteroids.
  • There is minimal systemic absorption with mometasone and fluticasone. It is modest for most other topical corticosteroids but high for betamethasone and dexamethasone, which should be used in the short-term only. Sprays are preferable in that they result in less systemic absorption and correct use also reduces the side-effects.
  • Fluticasone, mometasone and budesonide have not been shown to affect children's growth, unlike beclometasone.
  • Side-effects include dryness and irritation, epistaxis (10% of users) and rarely, ulceration, headaches, smell disturbances and raised intraocular pressure. Application should be carefully done with the head tilted forward and down ("bend over and apply with your face looking towards your tummy") or with the patient lying flat on a bed to ensure the drops reach the ethmoid air sinuses.
• Systemic corticosteroids:⁷ there is currently not much literature regarding the use of oral steroids for this condition but there is weak evidence suggesting that these may be useful in addressing all the symptoms (including hyposmia) associated with nasal polyps. Oral steroids have been shown to dramatically reduce polyp size in a few days² but the usual caveats regarding their prescription apply and this is best left to specialists.
• Medical polypoidectomy: this is the regimen used to treat large polyps. It consists of oral prednisolone (0.5 mg/kg) for 5-10 days with betamethasone nasal drops two drops per nostril t.d.s. in the ‘head upside down’ position for 5 days, then twice daily until the bottle runs out. It is complimented with maintenance therapy: fluticasone (drops, spray) or mometasone (spray) twice daily until the bottle runs out.

Other treatment options

• Medical modalities:³ studies have shown that macrolides can reduce nasal polyps if used over a period of weeks or months and azelastine may also have some degree of benefit. Aspirin desensitisation may help in aspirin sensitive individuals.
• Surgery:² this is carried out in conjunction with medical therapy. It removes the obstruction but does not affect the associated rhinitis. Procedures vary depending on size and number of polyps. Approach may be intra-nasal or external.
  • A polypectomy is an endonasal procedure carried out under local or general anaesthesia, involving removal of the polyps via the nostrils, most often using a cutting snare.
  • Ethmoidectomy involves clearing the ethmoid cells, which may be done endoscopically. More radical similar procedures can be carried out involving the frontal and sphenoid sinuses. This procedure is thought to reduce recurrence rate although there is some controversy surrounding this.
  • Post-operative management includes a nasal douche, topical intranasal steroids and a broad-spectrum antibiotic if infected sinus secretions were found during the procedure. Normal activities can usually resume within 2-3 weeks.⁸
  • Serious complications are rare (0.26%⁸) and include significant epistaxis, loss of vision (inadvertent penetration of orbit during endoscopic procedure) and cerebrospinal fluid leak secondary to skull base penetration.

There is no single curative treatment: recurrence is common with 60% of patients having a further procedure within 5 years of surgery and 5-10% of patients experiencing further severe disease. Single large polyps are less likely to recur¹ but patients with polyps and asthma are more likely to get further problems.⁸ Steroid nasal sprays help in reducing the recurrence rate but repeated surgery is often needed too.

Up to 8% of patients with nasal polyps have aspirin and NSAID sensitivity, rhinosinusitis and usually have concomitant asthma.

Presentation

• Typically in third and fourth decades of life.
• It is more common in females and in non-atopics.
• Ingestion of aspirin or an NSAID induces a reproducible reaction within 20–120 min:
  • In any individual the form of the reaction is consistent and any combination of symptoms may occur.
  • These include systemic upset with facial flushing, perspiration and intense lethargy, rhinorrhoea, nasal congestion, conjunctivitis and respiratory symptoms (cough and bronchospasm). Some individuals develop gastrointestinal symptoms. A severe reaction can include shock and respiratory arrest.

Aspirin sensitivity is associated with severe rhinosinusitis and asthma, with increased intensity of eosinophilic inflammation and of cytokines.

Diagnosis

Aspirin sensitivity should be suspected in patients with severe or recurrent nasal polyps and intrinsic asthma. There is no blood test with sufficient sensitivity or specificity and the diagnosis rests upon either a clear history of two aspirin/NSAID-induced reactions or by aspirin challenge (nasal, inhaled or oral).

Management

• Patients should be warned to avoid all drugs with COX1 inhibitory activity. Selective COX2 inhibitors appear to be safe but it has been suggested that the first dose should be administered in hospital under direct observation with monitoring
  for 2 hours and resuscitation facilities available.
• Paracetamol is usually (not always) tolerated in aspirin sensitive asthma. Single doses of up to 500 mg appear to be safe in 94% of patients.
• The role of diet avoiding preservatives, additives and high salicylate foods is controversial.
• Aspirin desensitisation can be carried out in a hospital setting.
• Surgery is less successful in aspirin-sensitive compared with aspirin-tolerant individuals with relapse occurring earlier.