Broncholithiasis can occur under a variety of circumstances.
Causes of broncholithiasis include:
(1) erosion of a calcified lymph node into an adjacent bronchus
(2) erosion of calcified bronchial cartilage into bronchial lumen
(3) calcification of inspissated mucus
(4) calcification of aspirated foreign material
(5) aspiration of a bone
(6) migration of calcified material from a distant site (via fistula or other route)
Differential diagnosis:
(1) calcified endobronchial tumor
(2) fungus ball
where:
• A calcified fungus ball could become a broncholith.
