BOOP is Bronchiolitis Olibterans Organizing Pneumonia. BOOP is inflammation in the lungs.

Bronchiolitis is inflammation of the very small airways called the bronchioles, less than one millimeter in diameter. There are over 200,000 of these airways.

Obliterans means that the inflammation in these small airways completely fills the bronchioles and obliterates the opening of the airway with inflammation.

Organizing is a term used to describe the pattern of the inflammation cells.

Pneumonia means that the lung is filled with inflammation, where the blood takes up oxygen. The rounded structures where this occurs are called alveoli. There are millions of them. If unfolded, they create an area the size of a tennis court.

Dr. Epler first reported BOOP in 1985. Dr. Epler reported about 50 individuals who developed a flu-like illness, "crackles" in the lungs, and lung function tests that showed a decreased lung capacity and a decreased diffusion of oxygen into the blood. The chest x-ray showed "patchy shadows" in both lungs.

Dr. Epler named this illness bronchiolitis obliterans organizing pneumonia (BOOP) because this is the pattern seen by the pathologists - doctors who examine lung tissue material. Some colleagues refer to it as Epler's pneumonia.

Most of the time, about 80% of the time, the cause of BOOP is not known and referred to as idiopathic BOOP.

BOOP may be caused by an infection such as a virus or unusual bacteria can cause BOOP. There has been a report of BOOP caused by the malaria parasite.

BOOP may be caused by medications. These include some anti-cancer medications, a heart arrhythmia medication, antibiotics and the illicit use of cocaine.

BOOP can be associated with the rheumatological disorders such as rheumatoid arthritis or lupus erythematosus.

BOOP has been reported to occur in recipients of organ transplantation that include lung, bone marrow, kidney and liver transplants.

There are miscellaneous causes or associated disorders. Almost every month, there are new reports. For example, BOOP occurs after radiation therapy for breast cancer. BOOP is associated with lymphoma or other cancers. BOOP has occurred in textile workers exposed to an unusual type of textile dye. Remarkably, a high dose of L-Tryptophan, a popular supplement among health enthusiasts for use in sleep and pain disorders, can cause BOOP. There has been a report of BOOP from exposure to a high concentration of mold dust.

BOOP may also be secondary to an underlying lung disease. For example, BOOP may be the inflammation associated with idiopathic pulmonary fibrosis (IPF), which is also called usual interstitial pneumonia (UIP). This is a progressive scarring lung disease

Anyone, anywhere in the world can get BOOP. It occurs in both men and women equally. It usually develops between the ages of 40 years and 60 years. It can occur in children and in patients over 80 years old. BOOP may occur at any time of the year.

Causes of BOOP

Idiopathic BOOP. Most of the time, about 80% of the time, the cause of BOOP is not known and referred to as idiopathic BOOP. This is the most common type. Flu

Idiopathic Rapidly Progressive or Fulminant BOOP. This is a very rare form of BOOP. The duration of illness is generally a few days. It is a very serious form of the disease with severe symptoms and respiratory failure. Unfortunately, a high percentage of patients do not survive, but prompt initiation of corticosteroid therapy may be effective.

Focal nodular BOOP. Sometimes, the chest x-ray shows BOOP as a single rounded shadow. The BOOP has the appearance of a lung cancer. Because of this, the lesion is removed surgically. For the most part, these will not recur again. There may also be several nodules or masses. These usually also subside over time. In rare situations, these lesions represent the beginning of typical "idiopathic" BOOP. Prednisone therapy will then result in complete resolution.

Infection-related BOOP. BOOP is not contagious. However, BOOP can be caused by an infection such as a virus or unusual bacteria. Post infection BOOP has been reported after adenovirus pneumonia, cytomegalovirus (CMV) pneumonia, influenza pneumonia, Legionella pneumonia, Chlamydia pneumonia, and malaria. Usually, pneumonia from an infection resolves, but sometimes the pneumonia becomes "organized" into inflammation with a pattern of BOOP. Prednisone therapy is usually helpful and results in complete resolution.

Medication-related BOOP. Several medications have been associated with BOOP. These include long-term antibiotics, an anti-irregular heart rate medication, and anti-cancer drugs. The symptoms and response to therapy are similar to "idiopathic" BOOP. Cough develops, then shortness of breath, and the chest x-ray shows patchy infiltrates. Corticosteroid therapy often results in complete resolution.

Rheumatological BOOP. BOOP can be associated with the rheumatological disorders such as rheumatoid arthritis, lupus erythematosus and polymyositis. The clinical findings and radiographic features are similar to "idiopathic" BOOP. When BOOP is associated with one of these disorders, it is often responsive to corticosteroid therapy, but the percentage of complete resolution is less than in the "idiopathic" type.

Organ transplant BOOP. BOOP has been reported to occur in recipients of organ transplantation that include lung, bone marrow, kidney and liver transplants. Sometimes a virus causes the BOOP. There is a variable response to treatment.

Environmental or occupational exposure-related BOOP. BOOP can occur from workplace or environmental exposures, but there have been only 3 reports. One report described BOOP occurring among workers in textile airbrushing printing factories in Spain. Some workers responded to corticosteroid therapy, some did not, and some had residual symptoms. It was suggested that spraying procedures that delivered an aerosol of the textile printing dye caused the BOOP. The textile dying process was changed, and there have been no new cases. The second was a report of a person who developed BOOP from a cloud of dust from a mold that was growing on the top of orange juice in a carton container. The BOOP was cured with corticosteroid therapy. The third report was about a person who developed BOOP from smoke inhalation in a house fire.

Miscellaneous BOOP. BOOP occurs after radiation therapy, especially for breast cancer. BOOP is associated with lymphoma or other cancers. HIV infection can cause BOOP. Remarkably, a high dose of L-Tryptophan, a popular supplement among health enthusiasts for use in sleep and pain disorders, can cause BOOP. Seasonal BOOP has been reported among 12 people in England. The BOOP occurred every year in the last weeks of February and resolved by early May or earlier with corticosteroid therapy. Between relapses, patients were entirely symptom-free. The patients reported spontaneous remission of the first episode after a short illness. Eventually symptoms became more severe and corticosteroid therapy was often used which provided a rapid and complete resolution. Inflammatory bowel disease BOOP is rare but may occur among individuals with ulcerative colitis or Crohn's disease. There is rapid and sustained improvement with corticosteroid treatment in most patients. BOOP has also occurred among patients with thyroid diseases. There has been one report of BOOP occurring during a woman's menstrual cycle.

Secondary BOOP. BOOP may also be secondary to an underlying lung disease. For example, BOOP may be the inflammation associated with idiopathic pulmonary fibrosis (IPF), which is also called usual interstitial pneumonia (UIP). This is a progressive scarring lung disease

BOOP is not caused by cigarette smoke. However, the lung function tests of smokers may show obstruction of the airflow. Because of this, individuals who smoke cigarettes may have a slower response to the treatment and a slower recovery.

BOOP is not inherited. BOOP may occur in two family members, but so far there have been no reports to show that the BOOP was inherited.