|
|
| Line 1: |
Line 1: |
| __NOTOC__ | | __NOTOC__ |
| {{Idiopathic pulmonary fibrosis }} | | {{Idiopathic pulmonary fibrosis }} |
| {{CMG}} | | {{CMG}}; {{AE}} {{AEL}} |
| ==Overview== | | ==Overview== |
| ==Pathophysiology== | | ==Pathophysiology== |
| Pulmonary fibrosis has often been called an [[autoimmunity|autoimmune disease]]. However, it is perhaps better characterized as an abnormal and excessive deposition of fibrotic tissue in the pulmonary interstitium with minimal associated inflammation.<ref name="Selman">{{cite journal |last=Selman |first=Moisés |coauthors=Talmadge E. King, Jr.; and Annie Pardo |title=Idiopathic pulmonary fibrosis: prevailing and evolving hypotheses about its pathogenesis and implications for therapy |journal=Annals of Internal Medicine |year=2001 |volume=134 |number=2 |pages=136-51 |url=http://www.annals.org/cgi/content/abstract/134/2/136}}</ref> [[Autoantibodies]], a hallmark of autoimmune diseases, are found in a minority of patients with truly idiopathic pulmonary fibrosis. Moreover, many autoimmune diseases associated with "pulmonary fibrosis", such as scleroderma, are more frequently associated with a related but more inflammatory disease, nonspecific interstitial pneumonitis.<ref>{{cite journal |last=King, Jr. |first=Talmadge E. |title=Centennial review: clinical advances in the diagnosis and therapy of the interstitial lung diseases |url=http://ajrccm.atsjournals.org/cgi/content/full/172/3/268 |journal=American Journal of Respiratory and Critical Care Medicine |year=2005 |volume=172 |number=3 |pages=268-79}}</ref> It is associated with [[smoking]]<ref>{{cite journal |last=Nagai |first=Sonoko |coauthors=Yuma Hoshino, Michio Hayashi, Isao Ito |title=Smoking-related interstitial lung diseases |url=http://www.co-pulmonarymedicine.com/pt/re/copulmonary/abstract.00063198-200009000-00005.htm |journal=Current Opinion in Pulmonary Medicine |volume=6 |issue=5 |pages=415-9 |year=2000 |pmid=10958232}}</ref> and exhibits some dependency on the amount of smoking.<ref>{{cite journal |last=Baumgartner |first=KB |coauthors=Samet JM, Stidley CA, Colby TV, Waldron JA |title=Cigarette smoking: a risk factor for idiopathic pulmonary fibrosis |url= http://ajrccm.atsjournals.org/cgi/content/short/155/1/242 |journal=American Journal of Respiratory and Critical Care Medicine |volume=155 |number=1 |pages=242-248 |year=1997 |pmid=9001319}}</ref>
| | ==Genetics== |
| | | ==Microscopic pathology== |
| ==Pathology== | | ==Gross pathology== |
| ;Histology
| |
| {{main article|Usual interstitial pneumonia}}
| |
| | |
| [[Image:Usual interstitial pneumonia (1).JPG|left|200px|thumb|[[Micrograph]] of usual interstitial pneumonia (UIP). UIP most often represents '''idiopathic pulmonary fibrosis'''. [[H&E stain]]. [[Autopsy]] specimen.]]
| |
| | |
| [[Histology|Histologic]] specimens for the diagnosis of IPF must be large enough that the pathologist can comment on the underlying lung architecture.
| |
| | |
| Small biopsies, such as those obtained via transbronchial lung biopsy (performed during [[bronchoscopy]]) are generally not sufficient for this purpose. Hence, larger biopsies obtained surgically via a thoracotomy or thoracoscopy are usually necessary.
| |
| | |
| The histological pattern of fibrosis associated with '''IPF''' is referred to as usual interstitial pneumonia (UIP).
| |
| | |
| Although '''UIP''' is required for the diagnosis of '''IPF''', it can be seen in other diseases as well.<ref>{{cite book |title=Robbins and Cotran's Pathological Basis of Disease |edition=7th ed. |first=Vinay |last=Kumar |coauthors=Nelso Fausto and Abul Abbas |year=2005 |publisher=Saunders |isbn=978-0721601878 |pages=729}}</ref>
| |
| | |
| Key features of UIP include fibroblast foci, a pattern of temporal heterogeneity, dense interstitial fibrosis in a paraseptal and subpleural distribution, and a relatively mild or minor component of interstitial chronic inflammation.<ref name=ATS2/> To help narrow the differential diagnosis, an absence of significant [[granuloma|granulomatous]] inflammation, [[microorganism]]s, [[eosinophil]]s, and [[asbestosis|asbestos bodies]] is required.
| |
|
| |
|
| ==References== | | ==References== |