Interstitial Lung Disease

An immunosuppressant used for almost all ILD that can be treated with immunosuppressants, except for IPF, PAP, LAM and smoking-related ILD (RBILD, DIP and PLCH). It works by suppressing proliferation of immune cells and is taken daily, usually split into morning and evening doses. Typical doses range from 75 to 200 mg total per day. The most common side effects include abdominal cramping, diarrhea, hair loss and fatigue. Toxicities include low blood counts and liver inflammation, although the liver inflammation is less prominent than with methotrexate and leflunomide. Its toxicity is generally monitored with blood work every four to 12 weeks.

A procedure to examine the airways leading to your lungs, which is usually performed on an outpatient basis (with no hospital stay). It involves passing a narrow, flexible instrument through the mouth or nose and into the airways and is helpful for diagnosing certain types of interstitial lung disease, most commonly including sarcoidosis, chronic beryllium disease, lymphangioleimyomatosis, pulmonary alveolar proteinosis, and pulmonary Langerhans cell histiocytosis. It also is useful as a research tool, to exclude infections. During a bronchoscopy, additional procedures may be performed including bronchoalveolar lavage, bronchoscopic biopsies (taking a sample of airways mucosa or of alveoli), and needle aspiration sampling of lymph nodes or masses.

A procedure performed during bronchoscopy that involves washing out a segment of the lung with salt water to remove cells and proteins from the air sacs (alveoli). It is most frequently used for research sampling of the alveolar cells, checking for infection and looking at the alveoli cell components. The proportions of types of immune cells in the BAL can suggest or rule out some types of ILD. Except for rare situations, BAL does not give a definitive diagnosis of any ILD.

Also known as a chest radiograph, X-rays are useful for follow-up of ILD, and in certain cases is sufficient for diagnosis, such as for sarcoidosis. However, today, most patients also have a diagnostic chest CT. The chest X-ray is preferred as a tool for helping monitor the progress of the disease, in conjunction with breathing tests and symptoms

An alkylating agent (one that changes the metabolism), slowing or stopping cell growth. For this reason, cyclophosphamide is used mostly for the treatment of cancer. Since the drug also decreases the immune system’s response to various diseases, it is used to treat other medical conditions, such as interstitial lung disease – especially in cases of scleroderma associated with lung compromise.

Can be administered either orally (by mouth) or intravenously (by IV). Side effects are numerous and include an increased long-term risk of developing bladder cancer. For this reason, cyclophosphamide is used only for short periods of time (six months to one year). Other adverse drug reactions are nausea, vomiting, stomachache, diarrhea, hair loss, increased risk to infections and hemorrhagic cystitis.

With this medication, close follow-up is needed, with monthly blood work. It should be taken early in the morning with an adequate fluid intake.

An immunosuppressant drug, one of the first used in organ transplantation and remains widely used today. It reduces the activity of the immune system by interfering with the activity and growth of T cells (a type of blood cell that fights infection).

Cyclosporin also is used to treat other different diseases, including Interstitial Lung Disease, especially these related with connective tissue diseases. It may be administered either orally (by mouth) or intravenously (by IV). Side effects may include kidney toxicity, gingival hyperplasia, peptic ulcers, fever and diarrhea. Today, this medication is being used less frequently, given newer, more potent and less toxic options.

This is a test of gas exchange at rest. It measures the ability of the lungs to transfer oxygen out of the atmosphere and into the bloodstream. DLCO is typically impaired in ILD due to thickening of the space between the air sacs and the blood compartment (capillaries) from inflammation or scarring.

DLCO is usually followed over time to look for progression of the disease, but it is more variable from day-to-day than the spirometry and also more affected by varying techniques in different pulmonary function labs. Therefore, a change of at least 10 to 20 percent is necessary to confidently suspect that there is an actual difference between tests. Some causes of low DLCO besides infiltration in the wall of the air sac include pulmonary hypertension, low hemoglobin levels (anemia) and technical difficulties with the test.

A CT scan of the lungs using specific protocols. This type of CT scan is best used at the time of diagnosis and later only when an unusual aspect of the disease occurs which requires the physician to look for complications or additional diseases.

For ILD, this type of chest CT should be obtained without IV contrast (dye), and with thin sections to allow for detailed examination of the lung tissue. With an experience CT reader, many ILDs can be diagnosed with a high degree of confidence using CT alone, without the need for a biopsy. For example, IPF can be diagnosed with over 90 percent confidence when the CT scan demonstrates certain characteristic findings. In those cases, the risk of a surgical lung biopsy usually outweighs the small chance of finding a different diagnosis than IPF.

FVC is commonly reduced when the lungs are stiffened by scar or inflammation, the breathing muscles are weak or different techniques are used to obtain it. A significant change of FVC over time (typically 5 to 10 percent) indicates a clinically useful improvement or an important deterioration. The forced expiratory volume in 1 second (FEV1), the amount exhaled in the first second of spirometry, may be disproportionately low when there is obstruction of airflow. There are several standard equations to predict normal values, so it is important to look at raw numbers, not percent predicted values, when comparing tests from two different institutions.

An immunosuppressant used mainly for sarcoidosis and hypersensitivity pneumonitis, though it may theoretically be useful for other ILD with predominant lymphocyte involvement. It works by suppressing proliferation of a type of immune cells, lymphocytes. Leflunomide is taken once daily, with the most common dose being 20 mg daily. The most common side effects include abdominal cramping, diarrhea and hair loss. Toxicities include liver inflammation, lung inflammation and neuropathy (burning, tingling or numbness usually starting in the toes and fingers). Its toxicity is monitored with blood work, initially every four weeks for the first six months, then less frequently. Because it remains in the system for months after stopping it, cholestyramine (a cholesterol medication) must be taken for two days to remove it via the stool if an individual needs to stop leflunomide quickly.

These pulmonary function tests measure the total gas volume in the lungs as well as the amount of gas remaining in the lungs after normal and forced expiration. The purpose of measuring these is to look for trapped air remaining in the lungs after expiration, confirm the presence of low forced vital capacity, and measure the relative contributions of lung tissue, chest wall stiffness and airways obstruction to low spirometry values.

An immune suppressant that is typically taken once weekly. It is used most commonly for sarcoidosis, and sometimes for ILD associated with rheumatologic conditions. Typical doses range from 7.5 to 20 mg weekly. The most common side effects include nausea, fatigue, hair loss and headache. Methotrexate can cause liver enzyme elevations (and occasionally liver fibrosis), low blood counts and sometimes lung inflammation. Its toxicity is generally monitored with blood work every four to 12 weeks.

An immunosuppressant that works by suppressing proliferation of immune cells. It is newer and more expensive than some other immune suppressants. It is used for almost all ILD that can be treated with immunosuppressants—notable exceptions include IPF, PAP, LAM, and smoking-related ILD (RBILD, DIP and PLCH).

Mycophenolate is taken daily, usually split into morning and evening doses, with doses typically ranging from 1000 to 3000 mg total per day. The most common side effects include abdominal cramping, diarrhea and fatigue. Toxicities include low blood counts. Its toxicity is generally monitored with blood work every four to 12 weeks.

Normally, the oxygen level (saturation) in the blood does not drop with exercise. However, in ILD, the lungs often cannot keep up with the increased blood flow that occurs during exercise, so oxygen saturation may drop during exertion. If the saturation is too low, it can lead to consequences such as breathlessness, or low oxygen delivery to important organs like the brain or the heart.

While this desaturation may be tolerable in mild forms or for brief periods, over time it can lead to excess strain on the right side of the heart. The effects on the brain are likewise thought to be unfavorable, based on studies of mountain climbers. In addition, since oxygen levels typically drop by a few percentage points while sleeping, it is advisable to measure them during sleep if the resting daytime level is already low (less than 95 percent). With prolonged exertion, persisting low levels of oxygen saturation (less than 88 percent) should be avoided. If the desaturation is likely to be very brief, then the benefits of using oxygen therapy are unknown and should be discussed with a physician. The usual maximum flow that can be delivered is six liters per minute, but it can be supplemented with transtracheal oxygen therapy.

The most commonly used corticosteroid in the United States. Corticosteroids suppress multiple arms of the immune system, work relatively quickly and are among the most reliable medications. Thus, they are often used for initial treatment for ILD. However, they can cause a range of toxicities over time, including mood changes, elevated blood sugar (diabetes), glaucoma, cataracts, water retention, high blood pressure, stomach ulcers, bone thinning, skin thinning, hip bone necrosis (loss of blood supply to the hip bone), infections and weight gain. Dosing of prednisone for interstitial lung diseases is not standardized, but most experts start with doses ranging from 30 to 60 mg daily with reductions (tapering) over time. Individuals using more than 15 to 20 mg of prednisone daily should generally also take a prophylactic antibiotic to help prevent infections and consider steps to prevent bone loss.

An individualized exercise regimen designed to improve exercise limitations. While there are no exercises that improve the lungs themselves, pulmonary rehabilitation decreases the amount of work that the lungs must do by improving muscle efficiency and cardiovascular fitness. In ILD patients, pulmonary rehabilitation has been shown to improve the ability to do activities, reduce shortness of breath and improve the quality of life in those with idiopathic pulmonary fibrosis. It is used for other ILD for its anecdotal evidence, although there are little or no data supporting its use in those diseases. We typically prescribe pulmonary rehab for 36 sessions over 12 weeks, followed by exercises being continued at home.

A timed walk that measures exercise capacity and whether oxygen levels in the blood are adequate during exertion. In some ILDs, the six-minute walk test has been shown to correlate with the severity of pulmonary function tests, the likelihood of disease progression and risk of death. However, it does not usually shed much light on breathlessness during activity, or assessing whether breathing tests are deteriorating over time. It is most useful as a research tool.

A pulmonary function test where a maximal effort is used to exhale in order to measure lung capacity (forced vital capacity, FVC). Airflow obstruction is commonly seen in several of the ILDs, including sarcoidosis, hypersensitivity pneumonitis, lymphangioleiomyomatosis, and bronchiolitis caused by connective tissue diseases (such as rheumatoid arthritis).

A biopsy (taking a tissue sample) performed in the operating room by a surgeon, either with an incision or using a videoscope that is inserted through small (approximately 1 cm each) incisions in the chest wall. A surgical lung biopsy carries higher risks than other diagnostic procedures, and may not be necessary when the chest CT or other testing is sufficiently definitive. Some ILDs (UIP, NSIP, chronic hypersensitivity pneumonitis, COP) are more likely to require surgical lung because of inconclusive CT scans and the fact that they cannot typically be diagnosed definitively with bronchoscopy.

A form of oxygen delivery in which a small hole (the diameter of a wet spaghetti noodle) is made in the neck to place a tube into the airway that is connected to a normal oxygen delivery system. It can be used alone or in conjunction with standard nasal oxygen to increase overall oxygen delivery. Typical flow rates with TTOT are lower than with nasal oxygen since the delivery is more efficient. TTOT catheters require some daily cleaning, and should be avoided in individuals using blood thinners or when there is substantial mucus. Many people prefer TTOT as it is less obstrusive and can be concealed better.

A group of disorders characterized by inflammatory destruction of blood vessels. Both arteries and veins can be affected.
The different types of vasculitis are classified by their underlying cause, if it can be identified, or according with the size of vessel affected: large, medium or small-vessel vasculitis.

Symptoms of vasculitis are many, often making it difficult to make the diagnosis. They may include chronic fever, weight loss, raised rash, muscle and join pain, numbness or tingling sensation over extremities, nose bleeds, bloody cough, shortness of breath, abdominal pain, bloody stools and dark urine. Blood tests to confirm the presence of ANCA antibodies can be helpful in making the diagnosis.

Sometimes, vasculitis affects the lungs seriously, and poses a high risk of mortality without adequate treatment. Treatment is based on the severity of the disease. Less severe cases may be treated with medications as methrotexate. Severe disease requires an aggressive approach with strong medications as cyclophosphamide. In the majority of cases, patients will be placed on long-term therapy to avoid relapse.