Makindo Medical Notes

👃 Anosmia is the complete loss of smell. While it can be an early sign of neurological disease, the commonest causes are ENT-related, particularly viral infections and chronic rhinosinusitis. A structured approach is key to avoid missing serious pathology while managing the majority of benign cases effectively.

📖 Clinical Approach

• History: Onset (sudden vs gradual), duration, associated nasal symptoms (obstruction, rhinorrhoea, facial pain), recent viral illness, head trauma, systemic symptoms, and drug history.
• Red flags 🚨: Unilateral obstruction with bleeding, neurological deficits, history of head trauma, or progressive decline without obvious ENT cause.
• Examination:
  • Anterior rhinoscopy or nasal endoscopy: mucosal inflammation, polyps, obstruction.
  • Neurological exam: cranial nerves, memory, Parkinsonian features.

🔍 Investigations

• ENT-focused: Nasal endoscopy, CT sinuses (if obstruction, polyps, or chronic sinusitis suspected).
• Neurological: MRI brain if associated neurological features or trauma.
• Olfactory testing: University of Pennsylvania Smell Identification Test (UPSIT) or simple bedside smell tests (coffee, peppermint).
• Blood tests: Consider autoimmune screen, thyroid, and infection markers if systemic disease suspected.

📝 Causes of Anosmia

💊 General Management Principles

• Treat the underlying cause — infection, allergy, polyps, neurological disease.
• Olfactory training: Regular exposure to strong familiar odours (coffee, lemon, rose, eucalyptus) twice daily for ≥12 weeks can improve recovery.
• Patient safety: Advise on food spoilage, gas leaks, and smoke alarms.
• Multidisciplinary care: ENT, neurology, and sometimes psychiatry (anosmia is linked with depression and reduced quality of life).

✅ Teaching Pearls

• Most anosmia is due to ENT pathology, not neurology.
• COVID-19 anosmia often recovers spontaneously — but smell training helps in persistent cases.
• Unilateral anosmia with obstruction and bleeding = red flag → suspect sinonasal tumour.
• Chronic rhinosinusitis and nasal polyps are the most common chronic ENT causes.
• Anosmia may precede Parkinson’s disease by years — useful early clue.

💡 Summary: Anosmia is usually benign and ENT-related, but clinicians must be alert for serious causes such as trauma, tumours, and neurodegenerative disease. A systematic approach — history, ENT exam, targeted imaging, and smell training — is essential for safe and effective care.