Diffuse Parenchymal Lung Diseases (Interstitial Lung Diseases)

Diffuse parenchymal lung diseases are disorders that affect the interstitial of the lung"the area around the lung’s air sacs. The most accurate way to determine if a lung disease affects this part of the lung is with a surgical biopsy. The term "interstitial lung diseases" has been replaced by the term "diffuse parenchymal lung diseases" which means that the diseases appear to affect the areas of the lung around the air sacs on chest X-rays and chest CT scans although, in reality, some of them might affect other areas of the lung when a lung biopsy is done.

There are hundreds of different types of diffuse parenchymal lung diseases and the number is rapidly increasing as our ability to analyze these diseases continues to improve. Generally, they can occur from one of the following causes:

  • Infection
  • Environmental exposure
  • Malignancy
  • Occupational exposure
  • Collagen vascular disease (an inflammatory condition of the body including the lung)
  • Drugs
  • Idiopathic (unknown causes)

The most common symptoms associated with diffuse parenchymal lung diseases are shortness of breath and cough. Other symptoms can include fever, arthritis, weight loss, and skin rashes. Occasionally, a patient with an diffuse parenchymal lung disease will have no symptoms and the disease will be detected incidentally on a chest X-ray or CT scan.

The evaluation of diffuse parenchymal lung diseases depends on specific medical history of the patient. Usually, some of the following tests are performed to evaluate the cause of lung disease:

  • Blood tests
  • Breathing tests (pulmonary function tests)
  • Chest X-ray
  • Chest CT scan

Bronchoscopy, a procedure in which a patient is sedated and then a flexible fiberoptic tube calleda bronchoscopeis placed through the patient’s nose or mouth into the windpipe (trachea) and advanced into the patient’s breathing tubes (bronchi) where a portion of the lung is washed with a salt water solution whereby cells and chemicals from the patient’s lung are collected and analyzed. This procedure is called "bronchoalveolar lavage." In addition to bronchoalveolar lavage, sometimes a small wire is placed inside the bronchoscope which has small scissors on its end. The small pieces of lung containing air sacs are cut out (biopsied) and pulled back through the bronchoscope for analysis by a pathologist. This procedure is called a transbronchial lung biopsy.

A surgical lung biopsy is often done by means of a video-assisted thoracoscopic (VATS) technique. With VATS, the patient receives a lung operation in the operating room under general anesthesia. The surgeon will make small incisions and insert a few sterile pipes into these incisions that extend into the lung. Fiberoptic equipment is then placed into the pipes and, by use of a video screen, the surgeon will introduce surgical equipment into these pipes to cut out lung tissue for biopsy and diagnosis. VATS has been a major advance in lung surgery, because the incisions required are much smaller than for traditional lung surgery and the complications from such surgery are fewer compared to traditional approaches.

Treatment of diffuse parenchymal lung diseases varies tremendously depending on the severity of the disease and its cause. At Albany Medical Center, our internationally renowned experts who specialize in lung diseases, as well as the experts who specialize in the most advanced radiology techniques and thoracic surgery, are available to manage and treat these complicated condition.