Introduction

• General term; many causes.
• Cause: inflammation of nasal passages.
• Signs: sneezing, nasal discharge.
• Diagnosis: signs, radiography, nasal flush or biopsy.
• Treatment: symptomatic or address underlying cause.
• Prognosis: guarded for resolution, may → chronic rhinitis.

Pathogenesis

Etiology

• Idiopathic.
• Parasitic in US nasal mites (rare).
• Congenital - cleft palate Cleft lip and palate.
• Traumatic, may also be infectious (periodontal abscess Periodontal disease is most common cause) → oronasal fistula Oronasal fistula.
• Neoplastic Nasal cavity: neoplasia - adenocarcinoma most common - >20% sarcoma (osteosarcoma, chondrosarcoma).
• Allergic.
• Viral infection (although rhinitis associated with viral infections it is a minor concern and not of primary diagnostic consideration):
  • CDV Canine distemper virus.
  • PI3 Canine parainfluenza virus 2.
  • Herpes Canine herpesvirus.
  • Adenovirus Canine adenovirus type 1.
• Fungal infection:
  • Aspergillosis Nasal aspergillosis/penicillosis.
  • Penicillium (or penicillosis).
• Bacterial infection:
  • Bordetella Bordetella bronchiseptica.
  • Pasteurella Pasteurella multocida.
• Other secondary infections:
  • Foreign body Airway foreign body.
• Cleft palate Cleft lip and palate.
• Oronasal fistula Oronasal fistula.
• Epistaxis.

Predisposing factors

General

• Structural defects and regurgitation predispose to secondary rhinitis.

Specific

• IgA deficiency, ciliary dyskinesia Primary ciliary dyskinesia - rare, predispose to secondary bacterial infection.

Pathophysiology

• Underlying defect or immune system dysfunction → secondary bacterial (or occasionally fungal) invasion.
• Initially acute inflammation (may) → chronic hyperplasia of nasal mucosa → chronic rhinitis.
• Foreign body lodged within the nasal cavity.
• Destructive lesion associated with neoplasia.

Timecourse

• Depends on cause.
• Acute (over drugs).
• May persist for life.

Diagnosis

Treatment

Outcomes