If chest x-rays or a lung biopsy shows that scarring isn't extensive, the usual treatment is a corticosteroid, such as prednisone. A doctor evaluates the patient's response using chest x-rays and pulmonary function tests. A few people who aren't helped by prednisone may improve with azathioprine or cyclophosphamide. Several medical centers are using lung transplantation in people with severe idiopathic pulmonary fibrosis. The prognosis varies greatly.
Most people continue to get worse.
Desquamative interstitial pneumonia responds better to corticosteroid treatment, and the survival time is greater and the death rate is lower for people with this variant. Lymphoid interstitial pneumonia is sometimes relieved by corticosteroids. Letterer-Siwe disease starts before age 3 and is usually fatal without treatment. The histiocytes damage not only the lungs but also the skin, lymph glands, bone, liver, and spleen. The lungs and bones are most frequently affected.