48,466
edits
Difference between revisions of "Hypersensitivity pneumonitis"
Jump to navigation
Jump to search
Hypersensitivity pneumonitis (view source)
Revision as of 19:06, 17 March 2015
, 19:06, 17 March 2015→Microscopic
(redirect +cat.) |
|||
| (6 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
{{ Infobox diagnosis | |||
| Name = {{PAGENAME}} | |||
| Image = Hypersensitivity pneumonitis intermed mag.jpg | |||
| Width = | |||
| Caption = Hypersensitivity pneumonitis. Trichrome stain. | |||
| Synonyms = extrinsic allergic alveolitis | |||
| Micro = centrilobular prominence of lesions, [[granulomata]], chronic interstitial inflammation consisting primarily of lymphocytes, interstitial fibrosis, air space involvement (alveolitis) | |||
| Subtypes = | |||
| LMDDx = [[usual interstitial pneumonia]], [[asbestosis]] | |||
| Stains = | |||
| IHC = | |||
| EM = | |||
| Molecular = | |||
| IF = | |||
| Gross = | |||
| Grossing = | |||
| Site = [[lung]] - see ''[[diffuse lung diseases]]'' | |||
| Assdx = | |||
| Syndromes = | |||
| Clinicalhx = allergen exposure | |||
| Signs = | |||
| Symptoms = | |||
| Prevalence = uncommon | |||
| Bloodwork = | |||
| Rads = upper lung predominant | |||
| Endoscopy = | |||
| Prognosis = usu. good if allergen exposure eliminated | |||
| Other = | |||
| ClinDDx = other [[diffuse lung diseases]], esp. [[idiopathic pulmonary fibrosis]] | |||
| Tx = eliminate allergen exposure | |||
}} | |||
'''Hypersensitivity pneumonitis''', abbreviated '''[[HP]]''', is a [[diffuse lung diseases]] caused by an allergen. | |||
It is also known as '''extrinsic allergic alveolitis''', abbreviated '''EAA'''. | |||
==General== | |||
*Exposure to stuffs... e.g. moldy hay - ''Farmer's lung'', atypical mycobacteria - ''hot tub lung''. | |||
*Upper lung predominant disease. | |||
**Mnemonic ''FASSTEN'' - upper lung field: [[Farmer's lung]], [[Ankylosing spondylitis]], [[Sarcoidosis]], [[Silicosis]], [[Tuberculosis]] (miliary), [[Eosinophilic granuloma]], [[Neurofibromatosis]]. | |||
*An immune complex-mediated [[hypersensitivity]]<ref name=pmid8279154>{{Cite journal | last1 = Kaltreider | first1 = HB. | title = Hypersensitivity pneumonitis. | journal = West J Med | volume = 159 | issue = 5 | pages = 570-8 | month = Nov | year = 1993 | doi = | PMID = 8279154 | url = http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/8279154/?tool=pubmed }}</ref> (Gell-Coombs classification type III). | |||
**If chronic, may develop into a cell-mediated hypersensitivity (Gell-Coombs classification type IV).<ref>URL: [http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/pufrm.html http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/pufrm.html]. Accessed on: 4 December 2011.</ref> | |||
===Specific diseases/etiology=== | |||
Selected causes of hypersensitivity pneumonitis:<ref name=pmid21978856>{{cite journal |author=Zacharisen MC, Fink JN |title=Hypersensitivity pneumonitis and related conditions in the work environment |journal=Immunol Allergy Clin North Am |volume=31 |issue=4 |pages=769–86, vii |year=2011 |month=November |pmid=21978856 |doi=10.1016/j.iac.2011.07.004 |url=}}</ref> | |||
{| class="wikitable sortable" | |||
! Disease | |||
! Cause | |||
|- | |||
| Silicosis | |||
| silica exposure | |||
|- | |||
| |[[Asbestosis]] | |||
| asbestos | |||
|- | |||
| Flavour-worker's lung (popcorn lung) | |||
| diacetyl - used for butter flavour<ref name=pmid21618944>{{cite journal |author=Egilman DS, Schilling JH, Menendez L |title=A proposal for a safe exposure level for diacetyl |journal=Int J Occup Environ Health |volume=17 |issue=2 |pages=122–34 |year=2011 |pmid=21618944 |doi= |url=}}</ref> | |||
|- | |||
| [[Talcosis]] | |||
| | |||
|- | |||
| Sick building syndrome | |||
| volatile organic compounds, smoke, dampness | |||
|- | |||
| Berylliosis | |||
| beryllium | |||
|- | |||
| Coal worker’s pneumoconiosis | |||
| coal dust | |||
|} | |||
==Gross== | |||
*Peripheral or peribronchiolar.<ref name=pmid16434894>{{Cite journal | last1 = Churg | first1 = A. | last2 = Muller | first2 = NL. | last3 = Flint | first3 = J. | last4 = Wright | first4 = JL. | title = Chronic hypersensitivity pneumonitis. | journal = Am J Surg Pathol | volume = 30 | issue = 2 | pages = 201-8 | month = Feb | year = 2006 | doi = | PMID = 16434894 }}</ref> | |||
**Not large airways. | |||
==Microscopic== | |||
Features: | |||
* Lesions have centrilobular prominence - '''important feature'''. <ref name=pmid16061708/> | |||
** Allergens enter lung through airway which has a centrilobular location. | |||
* [[Granulomata]] (not typically seen in UIP) - '''important feature'''.<ref name=pmid16061708>{{Cite journal | last1 = Ohtani | first1 = Y. | last2 = Saiki | first2 = S. | last3 = Kitaichi | first3 = M. | last4 = Usui | first4 = Y. | last5 = Inase | first5 = N. | last6 = Costabel | first6 = U. | last7 = Yoshizawa | first7 = Y. | title = Chronic bird fancier's lung: histopathological and clinical correlation. An application of the 2002 ATS/ERS consensus classification of the idiopathic interstitial pneumonias. | journal = Thorax | volume = 60 | issue = 8 | pages = 665-71 | month = Aug | year = 2005 | doi = 10.1136/thx.2004.027326 | PMID = 16061708 }}</ref> | |||
* Chronic interstitial inflammation consisting primarily of lymphocytes. | |||
* Interstitial fibrosis. | |||
* Air space involvement (alveolitis). | |||
DDx: | |||
*[[Usual interstitial pneumonia]]. | |||
*[[Nonspecific interstitial pneumonia]]. | |||
===Images=== | |||
<gallery> | |||
Image:Hypersensitivity_pneumonitis_low_mag.jpg | Hypersensitivity pneumonitis - low mag. (WC/Nephron) | |||
Image:Hypersensitivity_pneumonitis_intermed_mag.jpg | Hypersensitivity pneumonitis - intermed. mag. (WC/Nephron) | |||
Image:Hypersensitivity_pneumonitis_high_mag.jpg | Hypersensitivity pneumonitis - high mag. (WC/Nephron) | |||
</gallery> | |||
==See also== | |||
*[[Diffuse lung diseases]]. | |||
*[[Pneumoconioses]]. | |||
==References== | |||
{{Reflist|2}} | |||
[[Category:Diagnosis]] | [[Category:Diagnosis]] | ||
[[Category:Diffuse lung diseases]] | |||