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Basics ⬇

Basics

Overview

  • Non-neoplastic, inflammatory growths arising from epithelium, usually originate from a stalk.
  • Nasal-uncommon; originate from the mucosa of the nasal turbinates and are inflammatory in dogs and cats.
  • Nasopharyngeal-relatively common; originate from the base of the epithelial lining of the tympanic bulla or eustachian tube; when polyps extend into the nasopharynx referred to as nasopharyngal polyps; when extending into the ear, known as middle ear polyps, aural or auricular polyps, or benign, inflammatory polyps.

Signalment

  • Nasal polyps-middle-aged to older dogs and cats.
  • Nasopharyngeal polyps-typically kittens and young adult cats, but can be seen in older cats (months-15 years), rarely seen in dogs.

Signs

Nasal Polyps

  • Chronic mucopurulent nasal discharge
  • Noisy breathing-stertor
  • Nasal congestion and/or discharge
  • Sneezing or epistaxis
  • Decreased nasal airflow, generally unilateral
  • Generally non-responsive to antibiotics

Nasopharyngeal or Aural Polyps

  • Inspiratory stridor
  • Gagging
  • Cyanosis
  • Voice change
  • Dysphagia
  • Chronic, non-responsive otitis
  • Head tilt
  • Nystagmus
  • Ataxia
  • Horner's syndrome

Causes & Risk Factors

Unknown-suspect congenital or response to chronic inflammatory processes.

Diagnosis ⬆ ⬇

Diagnosis

Differential Diagnosis

  • Feline upper respiratory disease complex
  • Nasopharyngeal stenosis
  • Chronic otitis externa or media
  • Nasal or nasopharyngeal foreign body
  • Laryngeal paralysis
  • Nasal neoplasia-lymphoma, nasal adenocarcinoma
  • Laryngeal neoplasia-squamous cell carcinoma, lymphoma, adenocarcinoma
  • Aural neoplasia-ceruminous adenocarcinoma

CBC/Biochemistry/Urinalysis

N/A

Other Laboratory Tests

FeLV/FIV-general retroviral screening

Imaging

  • Skull radiographs-soft tissue density within nasal cavity, nasopharynx, tympanic bulla, external ear canal; 25% false negative rate.
  • Computerized tomography and MRI-better sensitivity for nasal, nasopharyngeal, and aural masses.

Diagnostic Procedures

  • Digital palpation of soft palate, visual examination of the nasopharynx and larynx under general anesthesia utilizing spay hook, dental mirror, and laryngoscope.
  • Flexible fiber-optic caudal rhinoscopy to examine the dorsal nasopharynx, choanae, and caudal nasal cavity.
  • Rigid rostral rhinoscopy to examine the nasal cavity.
  • Deep otoscopic examination.
  • Fine-needle aspirate and/or biopsy.
  • Cytology and histopathology.

Treatment ⬆ ⬇

Treatment

Medications ⬆ ⬇

Medications

Drug(s)

  • Appropriate antimicrobial medications if secondary nasal or otic infection present.
  • Consider anti-inflammatory course of corticosteroids following traction removal of nasopharyngeal polyps; decreased recurrence rate reported.

Follow-Up ⬆ ⬇

Follow-Up

Miscellaneous ⬆

Miscellaneous

Abbreviations

  • FeLV = feline leukemia
  • FIV = feline immunodeficiency virus
  • MRI = magnetic resonance imaging

Suggested Reading

Greci V, Vernia E, Mortellaro CM. Per-endoscopic trans-tympanic traction for the management of feline aural inflammatory polyps: a case review of 37 cats. J Feline Med Surg 2014, 16(8):645–650.

Holt DE, Goldschmidt MH. Nasal polyps in dogs: five cases (2005 to 2011). J Small Anim Pract 2011 , 52(12):660–663.

Klose TC, MacPhail CM, Schultheiss PC, et al. Prevalence of select infectious agents in inflammatory aural and nasopharyngeal polyps from client-owned cats. J Feline Med Surg 2010, 12(10):769–774.

Oliveira CR, O'Brien RT, Matheson JS, et al. Computed tomography features of feline nasopharyngeal polyps. Vet Radiol Ultrasound 2012, 53(4):406–411.

Reed N, Gunn-Moore D. Nasopharyngeal disease in cats: Diagnostic investigation and specific conditions and their management. J Feline Med Surg 2012, 14(5):306–326.

Author Catriona M. MacPhail

Consulting Editor Lynelle R. Johnson