Idiopathic interstitial fibrosis is a disease characterized by diffuse
interstitial fibrosis of unknown etiology and frequently occurs between the ages of 50-70.
- Patients present with dry cough and shortness of breath.
- Clubbing, tachypnea and persistent coarse basal crackles are
encountered on physical exam. Often they are using accessory muscles of inspiration for
- Chest x-ray shows interstitial thickening, honeycombing and nodules
in various combination. In Desquamative interstitial pneumonitis alveolar features can be
- PFT shows a restrictive and diffusion defects.
Patients are hypoxic and desaturate significantly with exercise.
- The pathology, which is non-specific, varies with the stage of the disease.
- The dominant pattern is inflammatory early on leading to
organization of the exudate and interstitial fibrosis in the later stage.
- The severe septal thickening (fibrosis) leads to a "honeycomb"
appearance of the lung and pronounced alveolocapillary block.
- Desquamative Interstitial pneumonitis (DIP), Usual Interstitial Pneumonitis (UIP),
Lymphocytic Interstitial Pneumonitis( LIP) are various subgroups, probably of the same
Unknown. This pathologic condition may be the end stage of many different pulmonary
- Hypoxemia, dyspnea, cyanosis, pulmonary hypertension and cor pulmonale.
- Lungs become stiff and smaller leading to restrictive defect in PFT.
- There is barrier for gas transfer resulting in increased diffusion capacity.
- V/Q mismatch and diffusion barrier leads to widened A-a gradient.
- Transbronchial lung biopsy confirms pathologically interstitial fibrosis.
- It will be necessary to rule out other known causes for fibrosis like Silicosis
or drugs. A long list of conditions can give rise to interstitial fibrosis.
- Steroids is useful in acute stages when there is significant inflammatory
- Once the fibrosis is chronic or if the chest X-ray has been stable for years or
if there is honeycombing, therapy is of no benefit.
- In some cases Methotrexate, Plasmapheresis and Lung Transplant are
- Oxygen is often prescribed for these patients, probably not influencing pulmonary
- In the acute progressive form "Hamman-Rich Syndrome" the prognosis is
- In the chronic form patients can live long with disability.