Posts Tagged ‘diagnosis of lupus’

Bronchiolitis Obliterans Organizing Pneumonia

Bronchiolitis obliterans organizing pneumonia:

Bronchiolitis obliterans organizing pneumonia (BOOP) is an inflammation of the bronchioles (bronchiolitis) and surrounding tissue in the lungs. It is an non infectious pneumonia.BOOP is often caused by a pre-existing chronic inflammatory disease like rheumatoid arthritis. BOOP can also be a side effect of certain medicinal drugs, e.g. amiodarone. BOOP was discovered by Dr. Gary Epler in 1985.It is also known as cryptogenic organizing pneumonia (COP), and some sources recommend using the latter term, to reduce confusion with bronchiolitis obliterans.The clinical features and radiological imaging resemble infectious pneumonia. However, diagnosis is suspected after there is no response to multiple antibiotics, and blood and sputum cultures are negative for organisms.

Background:

Radiation pneumonitis and fibrosis are well-recognized complications of thoracic radiotherapy, but less common complications include Bronchiolitis Obliterans Organizing Pneumonia (BOOP) and eosinophilic pneumonia . It is also not commonly appreciated that these complications can manifest in patients receiving radiotherapy for breast cancer. We report two such patients who developed a BOOP following post-operative radiotherapy to the thoracic wall. The clinical features, diagnostic considerations, and treatment of interstitial lung disease following radiotherapy will serve to alert clinicians to this clinical entity and provide guidelines for diagnostic workup.

Signs and symptoms:

     Cough

•      Dyspnea
•      Influenza-like symptoms
•      febrile illness
•      widespread crackles
•      mild resting hypoxemia

Most patients have a history suggestive of a slowly resolving viral pneumonia spanning weeks or a few months.  The most common symptom is a persistent, nonproductive cough, with some patients reporting flu-like symptoms with a fever, sore throat, and fatigue.  Shortness of breath is usually a significant symptom.  On physical exam of the lungs, crackles or a “Velcro” sound may be present and wheezes rarely are present.

Testing:

Chest x-rays may show bilateral patchy ground glass, a fine nodular pattern resembling miliary tuberculosis, bilateral symmetric lower lobe interstitial infiltrates, and on rare occasions, a normal chest x-ray.
Low blood oxygen is present in patients who are symptomatic.  Pulmonary function tests show a restrictive pattern, with reduction in the ability of gases to enter the blood stream from the lungs.  Airflow obstruction is uncommon in patients who are not smokers.  It is important to confirm the diagnosis of BOOP, because most patients will demonstrate complete clinical and physiologic recovery following therapy with corticosteroids.  This usually will require an open lung biopsy to distinguish BOOP from irreversible interstitial lung disease.

Diagnosis:

On clinical examination, crackles are common, and more rarely, patients may have clubbing. Laboratory findings are nonspecific.Almost 75% of people have symptoms for less than two months before seeking medical attention. A flu-like illness, with a cough, fever, a feeling of illness (malaise), fatigue, and weight loss heralds the onset in about 40% of patients. Doctors do not find any specific abnormalities on routine laboratory tests or on a physical examination, except for the frequent presence of crackling sounds (called rales) when the doctor listens with a stethoscope. Pulmonary function tests usually show that the amount of air the lungs can hold is below normal. The amount of oxygen in the blood is often low at rest and is even lower with exercise.

Treatment:

Early recognition and therapy of bronchiolitis obliterans is important, because treatment is often ineffective when the disease has reached the late, scarred stage.  Inhaled medication to open up airways are usually given for smooth muscle contraction and symptomatic relief.  Corticosteroids, if given early, may significantly alter the disease process.
Corticosteroid therapy should be continued for at least 2 to 3 months, then reduced slowly, to minimize the likelihood of relapses with premature cessation of therapy.  In some patients it may be necessary to continue low-dose or alternate-day corticosteroid therapy for months or years.There is a poor response to therapy for Bronchiolitis obliterans following bone marrow transplantation.  By the time severe airflow obstruction has been diagnosed, there is minimal if any therapeutic response.  Bronchodilators and corticosteroids have not improved airflow in most cases, and the use of immunosuppressive drugs occasionally is effective, but has not consistently changed bronchiolitis obliterans. Adding immunosuppression with high-dose corticosteroids are used to treat bronchiolitis obliterans after lung or heart-lung transplantation.  If this is detected early and therapy is initiated immediately, the chances of reversal are improved.  If therapy is begun late it may stabilize the process or have no effect.
Corticosteroid therapy in BOOP is effective in most cases, and is often dramatic within 1 to 2 days of starting therapy.  There is an approximately 65% complete and physiologic recovery in patients.Since this lesion is so steroid-responsive, it is important that the diagnosis is established early so that therapy can be started before irreversible changes in lung function begin.