Lymphoid Interstitial Pneumonia

(Lymphoid Interstitial Pneumonitis)

ByJoyce Lee, MD, MAS, University of Colorado School of Medicine
Reviewed/Revised Jul 2023
VIEW PROFESSIONAL VERSION

Lymphoid interstitial pneumonia is an uncommon lung disease in which mature lymphocytes (a type of white blood cell) accumulate in the air sacs of the lungs (alveoli).

  • People usually cough and have difficulty breathing.

  • Diagnosis requires chest x-ray, computed tomography, pulmonary function tests, and often bronchoscopy, biopsy, or both.

  • Treatment involves corticosteroids, immunosuppressants, or both.

(See also Overview of Idiopathic Interstitial Pneumonias.)

Lymphoid interstitial pneumonia is a form of idiopathic interstitial pneumonia. It can occur in children, usually those who have human immunodeficiency virus (HIV) infection or other immunodeficiencies. Lymphoid interstitial pneumonia can also occur in adults, often those with autoimmune disorders such as plasma cell disorders, Sjögren syndrome, Hashimoto thyroiditis, rheumatoid arthritis, and systemic lupus erythematosus (lupus). Women and girls are more commonly affected. Average age of affected adults is 54 years.

Symptoms of Lymphoid Interstitial Pneumonia

Children develop cough and decreased ability to exercise, and they may not grow and gain weight. Adults develop difficulty breathing and cough over months or, in some cases, years. Less common symptoms include weight loss, fever, joint pain, and night sweats.

Diagnosis of Lymphoid Interstitial Pneumonia

  • Chest computed tomography

Diagnosis requires chest x-ray, computed tomography (CT), and pulmonary function testing. Pulmonary function tests usually show a decrease in the amount of air the lungs can hold. Doctors sometimes do bronchoscopy and wash segments of the lung with a salt-water solution and then collect the washings (bronchoalveolar lavage) for testing.

Blood tests may reveal abnormalities in their blood proteins that can help establish the diagnosis. If not, lung biopsy is usually necessary.

Treatment of Lymphoid Interstitial Pneumonia

  • Corticosteroids or immunosuppressant medications

The prognosis is difficult to predict. The disorder may resolve on its own or after treatment, or it may progress to lung fibrosis or lymphoma (a cancer).

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