Table 3 Causes of pulmonary calcification and ossification

Pulmonary calcification

(A) Dystrophic

  1. Granulomatous diseases—granulomatous infection such as histoplasmosis and tuberculosis and non-infectious causes such as sarcoidosis.

  2. Other infections—viral infections such as varicella and parasitic infections such as paragonimiasis.

  3. Occupational lung diseases—silicosis, coal workers’ pneumoconiosis.

  4. Metabolic lung diseases—amyloidosis, Pulmonary alveolar microlithiasis.

  5. Vascular causes—areas of prior haemorrhage or infarction, pulmonary hypertension, arterio-venous malformation.

  6. Miscellaneous—post-treatment such as radiation therapy.

(B) Metastatic

  1. Non-neoplastic—most common cause is hypercalcaemia in the setting of chronic renal failure. Other causes are conditions causing primary hyperparathyroidism, iatrogenic (following calcium therapy), Paget’s disease.

  2. Neoplastic—parathyroid carcinoma, multiple myeloma, lymphoma/leukaemia and metastases such as chondrosarcoma.

Pulmonary ossification

 1. Nodular type—in chronic venous congestion.

 2. Dendriform type—in chronic lung insult with resultant fibrosis.

 3. Bone forming neoplasms such as osteosarcoma.