Bronchiolitis obliterans[1] | |
---|---|
Other names | Constrictive bronchiolitis,[2] Obliterative bronchiolitis, Popcorn lung |
High resolution CT scan showing bronchiolitis obliterans with mosaic attenuation, bronchiectasis, air trapping and bronchial thickening[3] | |
Specialty | Pulmonology |
Symptoms | Dry cough, shortness of breath, wheezing, feeling tired[1] |
Usual onset | Worsens over weeks to months in rare cases.[4] |
Causes | Toxic fumes, respiratory infections, connective tissue disorder, following a bone marrow or heart-lung transplant[1] |
Diagnostic method | CT scan, pulmonary function tests, lung biopsy[1] |
Differential diagnosis | Asthma[5] |
Treatment | Corticosteroids, immunosuppressive medication, lung transplant[1][4] |
Prognosis | Often poor[4] |
Frequency | Rare[4] |
Bronchiolitis obliterans (BO), also known as obliterative bronchiolitis, constrictive bronchiolitis and popcorn lung, is a disease that results in obstruction of the smallest airways of the lungs (bronchioles) due to inflammation.[1][6] Symptoms include a dry cough, shortness of breath, wheezing and feeling tired.[1] These symptoms generally get worse over weeks to months.[4] It is not related to cryptogenic organizing pneumonia, previously known as bronchiolitis obliterans organizing pneumonia.[4]
Causes include breathing in toxic fumes, respiratory infections, connective tissue disorder or complications following a bone marrow or heart-lung transplant.[1] Symptoms may not occur until two to eight weeks following toxic exposure or infection.[1] The underlying mechanism involves inflammation that results in scar tissue formation.[1] Diagnosis is by CT scan, pulmonary function tests or lung biopsy.[1] A chest X-ray is often normal.[4]
While the disease is not reversible, treatments can slow further worsening.[1] This may include the use of corticosteroids or immunosuppressive medication.[1] A lung transplant may be offered.[4] Outcomes are often poor, with most people dying in months to years.[4]
Bronchiolitis obliterans is rare in the general population.[4] It, however, affects about 75% of people by ten years following a lung transplant and up to 10% of people who have received a bone marrow transplant from someone else.[4] The condition was first clearly described in 1981.[4] Prior descriptions occurred as early as 1956, with the term "bronchiolitis obliterans" used first by Reynaud in 1835.[7][8]