Atrophic rhinitis (ozaena) is characterised by progressive atrophy of nasal mucosa with wide nasal cavities. The classic triad includes foul smell (which the patient is unaware of), crusting, and anosmia. The foul odour is caused by:
- A Necrosis of the nasal turbinate bones
- B Stagnant mucus colonised by Klebsiella ozaenae producing indole and ammonia ✓
- C Secondary sinusitis with anaerobic organisms
- D Septal perforation allowing turbulent unfiltered airflow
Correct answer: B. Stagnant mucus colonised by Klebsiella ozaenae producing indole and ammonia
Explanation
The foul-smelling odour (stench) of atrophic rhinitis is caused by proteolysis of stagnant mucus and epithelial debris by colonising bacteria, most characteristically Klebsiella ozaenae (Frisch's bacillus), along with other organisms. The patient is unaware of the odour because anosmia develops secondary to mucosal atrophy. The paradox of wide nasal cavities with subjective nasal obstruction (paradoxical nasal obstruction) is due to reduced nasal airflow resistance sensation from the atrophic turbinates.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.