Obliterative bronchiolitis
Updates to Article Attributes
Obliterative bronchiolitis (OB),also known as bronchiolitis obliterans or constrictive bronchiolitis, is a type of bronchiolitis and refers to bronchiolar inflammation with submucosal peribronchial fibrosis associated with luminal stenosis and occlusions. OBObliterative bronchiolitis should not be confused with bronchiolitis obliterans organising pneumonia (BOOP).
Epidemiology
Associations
Recognised associations include:
rheumatoid arthritis: considered the commonest connective tissue disease to be associated with obliterative bronchiolitis 11,12
medications, e.g. penicillamine
as a complication following lung transplantation: post lung transplant bronchiolitis obliterans 2; can occur in up to 10% of patients, usually within 6-12 months following bone marrow transplantation
1010
Clinical presentation
Its cardinal features are progressive breathlessness and a dry cough 14.
Pathology
The condition is characterised by concentric luminal narrowing of the membranous and respiratory bronchioles as a result of submucosal and peribronchiolar inflammation and fibrosis without any intraluminal granulation tissue or polyps/polyposis. There is an absence of diffuse parenchymal inflammation.
Aetiology
It can result from a number of causes:
idiopathic/cryptogenic
-
post-infectious
post
viral-viral (e.g. adenovirus)post
atypical-atypical infection (e.g. Mycoplasma pneumonia)
-
noxious fume inhalation
-
'popcorn"popcorn lung
'": workers of a microwave popcorn plant who had inhaled diacetyl, a chemical used for flavouring, developed obliterative bronchiolitis; the term has since become a colloquial synonym for obliterative bronchiolitis
-
neuroendocrine hyperplasia (pulmonary tumourlets) 4
-
post-transplant patients
-
heart/lung transplants 3
representing the obstructive form of chronic lung allograft dysfunction (CLAD)
-
A helpful mnemonic isMnemonic: CRITTS.
Radiographic features
Plain radiograph
Chest radiographic findings can be normal or, if abnormal, non-specific. Some associated features include:
attenuation of vascular markings
occasionally reticular/reticulonodular markings
CT
On HRCT chest, there are often sharply defined, areas of decreased lung attenuation associated with vessels of reduced calibre. These changes represent a combination of air trapping and oligaemia. This combination can give a mosaic attenuation pattern. Other features include:
History and etymology
It was first described by the French physician ACA C Reynaud in 1835 8,9.
Differential diagnosis
Consider:
-
panlobular emphysema: e.g. alpha-1-antitrypsin deficiency
usually has a lower lung zone predominance
-<p><strong>Obliterative bronchiolitis (OB)</strong>,<strong> </strong>also known as <strong>bronchiolitis obliterans</strong> or <strong>constrictive bronchiolitis</strong>, is a type of <a href="/articles/bronchiolitis">bronchiolitis</a> and refers to bronchiolar inflammation with submucosal peribronchial fibrosis associated with luminal stenosis and occlusions. OB should not be confused with <a href="/articles/cryptogenic-organising-pneumonia-1">bronchiolitis obliterans organising pneumonia (BOOP)</a>. </p><h4>Epidemiology</h4><h5>Associations</h5><p>Recognised associations include:</p><ul>-<li><a href="/articles/inflammatory-bowel-disease">inflammatory bowel disease</a></li>-<li>-<a href="/articles/rheumatoid-arthritis">rheumatoid arthritis</a>: considered the commonest connective tissue disease to be associated with obliterative bronchiolitis <sup>11,12</sup>-</li>-<li>medications, e.g. penicillamine</li>-<li>as a complication following lung transplantation: <a href="/articles/post-lung-transplant-bronchiolitis-obliterans-1">post lung transplant bronchiolitis obliterans</a> <sup>2</sup>; can occur in up to 10% of patients, usually within 6-12 months following bone marrow transplantation<sup> <sup>10</sup></sup>-</li>-<li>-<a href="/articles/swyer-james-syndrome">Swyer-James syndrome</a> <sup>13</sup>-</li>-</ul><h4>Clinical presentation</h4><p>Its cardinal features are progressive breathlessness and a dry cough <sup>14</sup>.</p><h4>Pathology</h4><p>The condition is characterised by concentric luminal narrowing of the membranous and respiratory bronchioles as a result of submucosal and peribronchiolar inflammation and fibrosis without any intraluminal granulation tissue or polyps/polyposis. There is an absence of diffuse parenchymal inflammation.</p><h5>Aetiology</h5><p>It can result from number of causes:</p><ul>-<li>idiopathic/cryptogenic</li>-<li>post-infectious<ul>-<li>post viral (e.g. adenovirus)</li>-<li>post atypical infection (e.g. <a href="/articles/mycoplasma-pneumonia"><em>Mycoplasma pneumonia</em></a>)</li>-</ul>-</li>-<li>noxious fume inhalation<ul><li>'popcorn lung': workers of a microwave popcorn plant who had inhaled diacetyl, a chemical used for flavouring, developed obliterative bronchiolitis; the term has since become a colloquial synonym for obliterative bronchiolitis</li></ul>-</li>-<li>neuroendocrine hyperplasia (<a href="/articles/pulmonary-tumourlet">pulmonary tumourlets</a>) <sup>4</sup>-</li>-<li>post-transplant patients<ul>-<li>heart/lung transplants <sup>3</sup><ul><li>representing the obstructive form of <a href="/articles/chronic-lung-allograft-dysfunction">chronic lung allograft dysfunction (CLAD)</a>-</li></ul>-</li>-<li>-<a href="/articles/haematopoietic-stem-cell-transplantation">haematopoietic stem cell transplants</a> <sup>7</sup> </li>-</ul>-</li>-</ul><p><strong>Mnemonic: </strong><a href="/articles/obliterative-bronchiolitis-mnemonic">CRITTS</a></p><h4>Radiographic features</h4><h5>Plain radiograph</h5><p>Chest radiographic findings can be normal or, if abnormal, non-specific. Some associated features include:</p><ul>-<li><a href="/articles/lung-hyperinflation-1">hyperinflation</a></li>-<li>attenuation of vascular markings</li>-<li>occasionally reticular/reticulonodular markings</li>-</ul><h5>CT</h5><p>On HRCT chest, there are often sharply defined, areas of decreased lung attenuation associated with vessels of reduced calibre. These changes represent a combination of air trapping and oligaemia. This combination can give a <a href="/articles/mosaic-attenuation-pattern-in-lung">mosaic attenuation pattern.</a> Other features include:</p><ul>-<li><a href="/articles/bronchiectasis">bronchiectasis</a></li>-<li>-<a href="/articles/bronchial-wall-thickening">bronchial wall thickening</a> <sup>6</sup>-</li>-<li>-<a href="/articles/ground-glass-opacification-3">ground glass opacities</a> <sup>6</sup>-</li>-</ul><h4>History and etymology</h4><p>It was first described by the French physician <strong>AC Reynaud</strong> in 1835 <sup>8,9</sup>.</p><h4>Differential diagnosis</h4><p>Consider:</p><ul>-<li>-<a href="/articles/asthma-1">asthma</a> </li>-<li>-<a href="/articles/panlobular-emphysema">panlobular emphysema</a>: e.g. <a href="/articles/alpha-1-antitrypsin-deficiency-4">alpha-1-antitrypsin deficiency</a><ul><li>usually has a lower lung zone predominance</li></ul>-</li>-<li>-<a href="/articles/pulmonary-hypertension-1">pulmonary hypertension</a><ul><li><a href="/articles/pulmonary-trunk-enlargement">pulmonary trunk enlargement </a></li></ul>-</li>- +<p><strong>Obliterative bronchiolitis (OB)</strong>,<strong> </strong>also known as <strong>bronchiolitis obliterans</strong> or <strong>constrictive bronchiolitis</strong>, is a type of <a href="/articles/bronchiolitis">bronchiolitis</a> and refers to bronchiolar inflammation with submucosal peribronchial fibrosis associated with luminal stenosis and occlusions. Obliterative bronchiolitis should not be confused with <a href="/articles/cryptogenic-organising-pneumonia-1">bronchiolitis obliterans organising pneumonia (BOOP)</a>. </p><h4>Epidemiology</h4><h5>Associations</h5><p>Recognised associations include:</p><ul>
- +<li><p><a href="/articles/inflammatory-bowel-disease">inflammatory bowel disease</a></p></li>
- +<li><p><a href="/articles/rheumatoid-arthritis">rheumatoid arthritis</a>: considered the commonest connective tissue disease to be associated with obliterative bronchiolitis <sup>11,12</sup></p></li>
- +<li><p>medications, e.g. penicillamine</p></li>
- +<li><p>as a complication following lung transplantation: <a href="/articles/post-lung-transplant-bronchiolitis-obliterans-1">post lung transplant bronchiolitis obliterans</a> <sup>2</sup>; can occur in up to 10% of patients, usually within 6-12 months following bone marrow transplantation<sup> 10</sup></p></li>
- +<li><p><a href="/articles/swyer-james-syndrome">Swyer-James syndrome</a> <sup>13</sup></p></li>
- +</ul><h4>Clinical presentation</h4><p>Its cardinal features are progressive breathlessness and a dry cough <sup>14</sup>.</p><h4>Pathology</h4><p>The condition is characterised by concentric luminal narrowing of the membranous and respiratory bronchioles as a result of submucosal and peribronchiolar inflammation and fibrosis without any intraluminal granulation tissue or polyps/polyposis. There is an absence of diffuse parenchymal inflammation.</p><h5>Aetiology</h5><p>It can result from a number of causes:</p><ul>
- +<li><p>idiopathic/cryptogenic</p></li>
- +<li>
- +<p>post-infectious</p>
- +<ul>
- +<li><p>post-viral (e.g. adenovirus)</p></li>
- +<li><p>post-atypical infection (e.g. <a href="/articles/mycoplasma-pneumonia"><em>Mycoplasma pneumonia</em></a>)</p></li>
- +</ul>
- +</li>
- +<li>
- +<p>noxious fume inhalation</p>
- +<ul><li><p>"popcorn lung": workers of a microwave popcorn plant who had inhaled diacetyl, a chemical used for flavouring, developed obliterative bronchiolitis; the term has since become a colloquial synonym for obliterative bronchiolitis</p></li></ul>
- +</li>
- +<li><p>neuroendocrine hyperplasia (<a href="/articles/pulmonary-tumourlet">pulmonary tumourlets</a>) <sup>4</sup></p></li>
- +<li>
- +<p>post-transplant patients</p>
- +<ul>
- +<li>
- +<p>heart/lung transplants <sup>3</sup></p>
- +<ul><li><p>representing the obstructive form of <a href="/articles/chronic-lung-allograft-dysfunction">chronic lung allograft dysfunction (CLAD)</a></p></li></ul>
- +</li>
- +<li><p><a href="/articles/haematopoietic-stem-cell-transplantation">haematopoietic stem cell transplants</a> <sup>7</sup> </p></li>
- +</ul>
- +</li>
- +</ul><p>A helpful mnemonic is<strong> </strong><a href="/articles/obliterative-bronchiolitis-mnemonic">CRITTS</a>.</p><h4>Radiographic features</h4><h5>Plain radiograph</h5><p>Chest radiographic findings can be normal or, if abnormal, non-specific. Some associated features include:</p><ul>
- +<li><p><a href="/articles/lung-hyperinflation-1">hyperinflation</a></p></li>
- +<li><p>attenuation of vascular markings</p></li>
- +<li><p>occasionally reticular/reticulonodular markings</p></li>
- +</ul><h5>CT</h5><p>On HRCT chest, there are often sharply defined, areas of decreased lung attenuation associated with vessels of reduced calibre. These changes represent a combination of air trapping and oligaemia. This combination can give a <a href="/articles/mosaic-attenuation-pattern-in-lung">mosaic attenuation pattern.</a> Other features include:</p><ul>
- +<li><p><a href="/articles/bronchiectasis">bronchiectasis</a></p></li>
- +<li><p><a href="/articles/bronchial-wall-thickening">bronchial wall thickening</a> <sup>6</sup></p></li>
- +<li><p><a href="/articles/ground-glass-opacification-3">ground glass opacities</a> <sup>6</sup></p></li>
- +</ul><h4>History and etymology</h4><p>It was first described by the French physician <strong>A C Reynaud</strong> in 1835 <sup>8,9</sup>.</p><h4>Differential diagnosis</h4><p>Consider:</p><ul>
- +<li><p><a href="/articles/asthma-1">asthma</a> </p></li>
- +<li>
- +<p><a href="/articles/panlobular-emphysema">panlobular emphysema</a>: e.g. <a href="/articles/alpha-1-antitrypsin-deficiency-4">alpha-1-antitrypsin deficiency</a></p>
- +<ul><li><p>usually has a lower lung zone predominance</p></li></ul>
- +</li>
- +<li>
- +<p><a href="/articles/pulmonary-hypertension-1">pulmonary hypertension</a></p>
- +<ul><li><p><a href="/articles/pulmonary-trunk-enlargement">pulmonary trunk enlargement</a></p></li></ul>
- +</li>