Table 1.

Causes of tracheomalacia.

Infections	Viral (H1N1, adenovirus, corona virus), bacterial, fungal (aspergillosis).
Inflammatory/infiltrative	Sarcoidosis, amyloidosis, rheumatoid, Wegener's granulomatosis, mustard gas, necrotising tracheitis, polyangiitis
Non-inflammatory	Trauma, idiopathic tracheal stenosis, Mounier -Kuln syndrome. Relapsing polychondritis.
Iatrogenic	Post tracheal intubation, high dose prednisolone
Neoplastic	Primary or secondary
Extrinsic compression	Lymph node enlargement, vascular anomalies, fibrosing mediastinitis, mediastinal granuloma, goitre