Difference between revisions of "Duodenum"

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The '''duodenum''' is the first part of the small bowel.  It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.   
[[Image:Duodenumanatomy.jpg|thumb|Schematic of the duodenum. (WC/Luke Guthmann)]]
The '''duodenum''' is the first part of the [[small bowel]] and receives food from the [[stomach]].  It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.   


An introduction to gastrointestinal pathology is in the ''[[gastrointestinal pathology]]'' article.
An introduction to gastrointestinal pathology is in the ''[[gastrointestinal pathology]]'' article.
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The clinical history is often: ''r/o celiac'' or ''r/o giardia''.
The clinical history is often: ''r/o celiac'' or ''r/o giardia''.


==Getting started==
=Getting started=
===PGY-2 DDx===
==Normal duodenum==
*Celiac.
*Abbreviated ''ND''.
===General===
*Very common.
 
===Microscopic===
*Three tall villi.
*Few intraepithelial lymphocytes; < 1 lymphocyte / 4 epithelial cells.
*No (pink) subepithelial collagen band.
*Predominant lamina propria cell: [[plasma cells]].
**Lack of plasma cells suggests ''[[common variable immunodeficiency]]'' (CVID).<ref name=pmid20629103>{{cite journal |author=Agarwal S, Smereka P, Harpaz N, Cunningham-Rundles C, Mayer L |title=Characterization of immunologic defects in patients with common variable immunodeficiency (CVID) with intestinal disease |journal=Inflamm Bowel Dis |volume= |issue= |pages= |year=2010 |month=July |pmid=20629103 |doi=10.1002/ibd.21376 |url=}}</ref>
*No organisms in lumen.
 
DDx:
*[[Intestinal metaplasia of the stomach]] - foveolar epithelium + other histologic components of the stomach.
*[[Chronic duodenitis]] - foveolar epithelium, [[Brunner's gland hyperplasia]].
 
===Sign out===
<pre>
Duodenum, Biopsy:
- Small bowel mucosa and Brunner's glands within normal limits.</pre>
 
<pre>
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
</pre>
 
<pre>
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
</pre>
 
<pre>
Small Bowel (Duodenum), Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
</pre>
 
====Block letters====
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA AND BRUNNER'S GLANDS WITHIN NORMAL LIMITS.
</pre>
 
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
</pre>
 
<pre>
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.
</pre>
 
<pre>
SMALL BOWEL (DUODENUM), BIOPSY:
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.
</pre>
 
==Basic DDx==
*Celiac sprue.
**Intraepithelial lymphocytes - '''key feature'''.
**Intraepithelial lymphocytes - '''key feature'''.
**Loss of villi.
**Loss of villi.
*Giarrdia.
*Giardia.
**Like celiac... but giarrdia organisms.
**Like celiac... but giardia organisms.
*Adenomas.
*Adenomas.
**Too much blue - similar to colonic adenomas.
**Too much blue - similar to colonic adenomas.
*Cancer.
*[[Cancer]].
**Too much blue and epithelium in the wrong place.
**Too much blue and epithelium in the wrong place.
====More====
*[[Helicobacter duodenitis|H. pylori]] only in areas of [[Gastric heterotopia of the duodenum|gastric metaplasia]].<ref>El-Zimaity. 18 October 2010.</ref>


===Duodenal nodules DDX===
===Duodenal nodules DDX===
Line 23: Line 88:
{{familytree | | | | | B01 | | | | | | | | | | | | | | B02 | | | | | | | | | | | | |B01=Benign<br>(common)| B02=Neoplastic}}
{{familytree | | | | | B01 | | | | | | | | | | | | | | B02 | | | | | | | | | | | | |B01=Benign<br>(common)| B02=Neoplastic}}
{{familytree | |,|-|-|-|+|-|-|-|.| | | |,|-|-|-|v|-|-|-|+|-|-|-|v|-|-|-|.| | | | | |}}
{{familytree | |,|-|-|-|+|-|-|-|.| | | |,|-|-|-|v|-|-|-|+|-|-|-|v|-|-|-|.| | | | | |}}
{{familytree | C01 | | C02 | | C03 | | C04 | | C05 | | C06 | | C07 | | C08 | | | | |C01=Brunner's<br>gland|C02=Heterotopic<br>gastric mucosa|C03=Lymphoid<br>nodule|C04=Adenoma|C05=NET|C06=Paraganglioma|C07=Prolapsed<br>gastric polyp|C08=Metastasis}}
{{familytree | C01 | | C02 | | C03 | | C04 | | C05 | | C06 | | C07 | | C08 | | | | |C01=Brunner's<br>gland|C02=[[Gastric heterotopia of the duodenum|Heterotopic<br>gastric mucosa]]|C03=Lymphoid<br>nodule|C04=Adenoma|C05=[[Neuroendocrine tumour|NET]]|C06=[[Paraganglioma]]|C07=Prolapsed<br>gastric polyp|C08=[[Metastasis]]}}
{{familytree/end}}
{{familytree/end}}


===Normal duodenum===
===Infections of the duodenum<ref>{{cite journal |author=Serra S, Jani PA |title=An approach to duodenal biopsies |journal=J. Clin. Pathol. |volume=59 |issue=11 |pages=1133–50 |year=2006 |month=November |pmid=16679353 |pmc=1860495 |doi=10.1136/jcp.2005.031260 |url=http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860495/?tool=pubmed}}</ref>===
*Three tall villi.
Common:
*Few intraepithelial lymphocytes; < 1 lymphocyte / 4 epithelial cells.
*[[Giardia]].
*No (pink) subepithelial collagen band.
Rare:
*Predominant lamina propria cell: plasma cells.
*[[Cryptosporidia]].
**Lack of plasma cells suggests ''common variable immunodeficiency'' (CVID).<ref name=pmid20629103>{{cite journal |author=Agarwal S, Smereka P, Harpaz N, Cunningham-Rundles C, Mayer L |title=Characterization of immunologic defects in patients with common variable immunodeficiency (CVID) with intestinal disease |journal=Inflamm Bowel Dis |volume= |issue= |pages= |year=2010 |month=July |pmid=20629103 |doi=10.1002/ibd.21376 |url=}}</ref>
*[[Microsporidia]].
*No organisms in lumen.
*Isospora belli.
*Cyclospora.
*MAC ([[Mycobacterium avium complex]]).
*CMV ([[cytomegalovirus]]).
*[[Cryptococcus neoformans]].
 
=Common stuffs=
==Gastric heterotopia of the duodenum==
*[[AKA]] ''heterotopic gastric mucosa''.
{{Main|Gastric heterotopia of the duodenum}}


==Celiac sprue==
==Celiac sprue==
*[[AKA]] ''celiac disease''.
{{main|Celiac sprue}}
{{main|Celiac sprue}}
==Giardiasis==
{{Main|Giardiasis}}
==Acute duodenitis==
*Abbreviated ''AD''.
{{Main|Acute duodenitis}}
==Chronic duodenitis==
===General===
===General===
*Etiology: autoimmune.
*This is not very well defined as [[plasma cell]]s are present in a normal duodenum.
 
===Gross===
*Duodenal erythema.
 
===Microscopic===
Features:
*"Abundant" lamina propria plasma cells.
*Villous blunting.
*[[Brunner's gland hyperplasia]].
 
DDx:
*[[Normal duodenum]].
 
===Sign out===
<pre>
DUODENUM, BIOPSY:
- MODERATE NON-SPECIFIC CHRONIC DUODENTIS (SMALL BOWEL MUCOSA WITH VILLOUS
  BLUNTING, PROMINENT BRUNNER'S GLANDS, ABUNDANT LAMINA PROPRIA PLASMA CELLS
  AND OCCASIONAL INTRAEPITHELIAL LYMPHOCYTES, WITHOUT FOVEOLAR METAPLASIA).
- NEGATIVE FOR DYSPLASIA.
</pre>
 
==Peptic duodenitis==
{{Main|Peptic duodenitis}}


====Epidemiology====
==Brunner's gland hyperplasia==
*Associated with:
:''Brunner's gland hamartoma'' redirects here.
**The skin condition ''[[dermatitis herpetiformis]]''.<ref>TN 2007 D22</ref>
*Abbreviated ''BGH''.
**IgA deficiency - 10-15X more common in celiac disease vs. healthy controls.<ref name=pmid12414763>{{Cite journal  | last1 = Kumar | first1 = V. | last2 = Jarzabek-Chorzelska | first2 = M. | last3 = Sulej | first3 = J. | last4 = Karnewska | first4 = K. | last5 = Farrell | first5 = T. | last6 = Jablonska | first6 = S. | title = Celiac disease and immunoglobulin a deficiency: how effective are the serological methods of diagnosis? | journal = Clin Diagn Lab Immunol | volume = 9 | issue = 6 | pages = 1295-300 | month = Nov | year = 2002 | doi = | PMID = 12414763 }}</ref>
*[[AKA]] ''Brunneroma''.<ref name=pmid12376792>{{Cite journal  | last1 = Tan | first1 = YM. | last2 = Wong | first2 = WK. | title = Giant Brunneroma as an unusual cause of upper gastrointestinal hemorrhage: report of a case. | journal = Surg Today | volume = 32 | issue = 10 | pages = 910-2 | month =  | year = 2002 | doi = 10.1007/s005950200179 | PMID = 12376792 }}</ref>
**Risk factor for ''gastrointestinal T cell lymphoma'' - known as: ''enteropathy-associated T cell lymphoma'' (EATL).
===General===
*Benign.
*Usually asymptomatic.<ref name=pmid18583897>{{Cite journal  | last1 = Lee | first1 = WC. | last2 = Yang | first2 = HW. | last3 = Lee | first3 = YJ. | last4 = Jung | first4 = SH. | last5 = Choi | first5 = GY. | last6 = Go | first6 = H. | last7 = Kim | first7 = A. | last8 = Cha | first8 = SW. | title = Brunner's gland hyperplasia: treatment of severe diffuse nodular hyperplasia mimicking a malignancy on pancreatic-duodenal area. | journal = J Korean Med Sci | volume = 23 | issue = 3 | pages = 540-3 | month = Jun | year = 2008 | doi = 10.3346/jkms.2008.23.3.540 | PMID = 18583897 }}</ref>  


====Clinical====
Note:
Treatment:
*The AFIP uses the term ''Brunner's gland hamartoma'' for lesions > 5 mm.<ref name=pmid16928936>{{Cite journal  | last1 = Patel | first1 = ND. | last2 = Levy | first2 = AD. | last3 = Mehrotra | first3 = AK. | last4 = Sobin | first4 = LH. | title = Brunner's gland hyperplasia and hamartoma: imaging features with clinicopathologic correlation. | journal = AJR Am J Roentgenol | volume = 187 | issue = 3 | pages = 715-22 | month = Sep | year = 2006 | doi = 10.2214/AJR.05.0564 | PMID = 16928936 }}</ref>
*Gluten free diet.
**Multiple lesions less than 5 mm are ''hyperplasia''.
**''Mnemonic'': BROW = barley, rye, oats, wheat.


Serologic testing:
===Gross===
*Anti-transglutaminase antibody.
*Nodularity of the duodenum.
**Alternative test: anti-endomysial antibody.
*IgA -- assoc. with celiac sprue.


===Microscopic===
===Microscopic===
Features:<ref name=Ref_PBoD843>{{Ref PBoD|843}}</ref>
Features:
*Enteritis.  
*Prominent Brunner's gland.
**Intraepithelial lymphocytes - '''key feature'''.
**Tubular structures - formed by cells abundant cytoplasm that is clear with eosinophilic "cobwebs" and a round, small basal nucleus without a nucleolus.
**Plasma cells.
**Brunner's glands close to the surface epithelium - '''key feature'''.<ref name=pmid4076734>{{Cite journal  | last1 = Franzin | first1 = G. | last2 = Musola | first2 = R. | last3 = Ghidini | first3 = O. | last4 = Manfrini | first4 = C. | last5 = Fratton | first5 = A. | title = Nodular hyperplasia of Brunner's glands. | journal = Gastrointest Endosc | volume = 31 | issue = 6 | pages = 374-8 | month = Dec | year = 1985 | doi =  | PMID = 4076734 }}</ref>
**Macrophages.  
*+/-Pancreatic acini and ducts.<ref name=pmid16928936/>
*Loss of villi - '''important feature'''.
 
**Normal duodenal biopsy should have 3 good villi.
DDx:
*Mitosis increased (in the crypts).
*Foveolar metaplasia (isolated) - see [[peptic duodenitis]].
*[[Peptic duodenitis]].


Image:
Image:
*[http://commons.wikimedia.org/wiki/File:Coeliac_path.jpg Celiac sprue (WC)].
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2526515/figure/F3/ BGH (nih.gov)].<ref name=pmid18583897/>
*[http://www.ajronline.org/content/187/3/715.full BGH (ajronline.org)].<ref name=pmid16928936/>


Notes:  
===Sign out===
*If you see acute inflammatory cells, i.e. neutrophils, consider Giardiasis and other infectious etiologies.
<pre>
*Biopsy should consist of 2-3 sites.  In children it is important to sample the duodenal cap, as it is the only affected site in ~10% of cases.
DUODENUM, BIOPSY:
- CONSISTENT WITH BRUNNER'S GLAND HYPERPLASIA.
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
</pre>


===Grading===
<pre>
Rarely done - see ''[[celiac disease]]'' article.
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
- PROMINENT BRUNNER'S GLANDS WITH EXTENSION INTO THE LAMINA PROPRIA.
</pre>


==Giardiasis==
====Superficial Brunner's glands====
===Etiology===
<pre>
*Flagellate protozoan ''Giardia lamblia''.
DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLANDS THAT ARE FOCALLY SUPERFICIAL.
- NO FINDINGS SUGGESTIVE OF CELIAC DISEASE.
- NEGATIVE FOR ACTIVE INFLAMMATION.
- NEGATIVE FOR DYSPLASIA.
</pre>
 
====Micro====
The sections show small bowel mucosa and a small amount of submucosa.  Brunner's glands are abundant and found focally in the lamina propria. 
 
The epithelium matures appropriately.  There is no increase in intraepithelial lymphocytes.  No foveolar metaplasia of the epithelium is identified.
 
==Helicobacter duodenitis==
*Helicobacter is the most common cause of duodenitis.<ref>URL: [https://www.saintlukeskc.org/health-library/duodenitis https://www.saintlukeskc.org/health-library/duodenitis]. Accessed on: 2024 Feb 5.</ref><ref>URL: [https://www.webmd.com/digestive-disorders/what-is-duodenitis https://www.webmd.com/digestive-disorders/what-is-duodenitis]. Accessed on: 2024 Feb 5.</ref>
*Overall, Helicobacter is rare in the duodenum.
**Infection associated with [[Gastric heterotopia of the duodenum|gastric metaplasia]].<ref name=pmid7769188>{{cite journal |authors=Yang H, Dixon MF, Zuo J, Fong F, Zhou D, Corthésy I, Blum A |title=Helicobacter pylori infection and gastric metaplasia in the duodenum in China |journal=J Clin Gastroenterol |volume=20 |issue=2 |pages=110–2 |date=March 1995 |pmid=7769188 |doi=10.1097/00004836-199503000-00007 |url=}}</ref>
 
===Sign out===
<pre>
A. Duodenum, Biopsy:
- Active duodenitis associated with foveolar epithelium and HELICOBACTER-LIKE ORGANISMS.
- NEGATIVE for dysplasia.
</pre>
 
=Weird stuff=
==Disaccharidases deficiency==
===General===
*Common among asians.
*Includes: lactase, sucrase, and maltase.
**Lactase changes seen with mild histomorphologic changes.<ref name=pmid2116456>{{cite journal |author=Langman JM, Rowland R |title=Activity of duodenal disaccharidases in relation to normal and abnormal mucosal morphology |journal=J. Clin. Pathol. |volume=43 |issue=7 |pages=537–40 |year=1990 |month=July |pmid=2116456 |pmc=502575 |doi= |url=}}</ref>
**Maltase and sucrase only affected in moderate and severe lesions.


===Histology===
===Microscopic===
*Loss of villi.
Features:<ref name=pmid2116456>{{cite journal |author=Langman JM, Rowland R |title=Activity of duodenal disaccharidases in relation to normal and abnormal mucosal morphology |journal=J. Clin. Pathol. |volume=43 |issue=7 |pages=537–40 |year=1990 |month=July |pmid=2116456 |pmc=502575 |doi= |url=}}</ref>
*Intraepithelial lymphocytes.
*Decreased villous-crypt ratio (mild to severe).
**+Other inflammatory cells, especially PMNs, close to the luminal surface.
*+/-Inflammation (only in moderate and severe).
*Flagellate protozoa -- '''diagnostic feature'''.
**Organisms often at site of bad inflammation.
**Pale/translucent on H&E.
**Size: 12-15 micrometers (long axis) x 6-10 micrometers (short axis) -- if seen completely.<ref>[http://www.water-research.net/Giardia.htm http://www.water-research.net/Giardia.htm]</ref>
***Often look like a crescent moon ([http://en.wikipedia.org/wiki/File:Crescent_Moon.JPG image of crescent moon]) or semicircular<ref>[http://en.wikipedia.org/wiki/Semicircle http://en.wikipedia.org/wiki/Semicircle]</ref> -- as the long axis of the organism is rarely in the plane of the (histologic) section.


Notes:  
DDx:
*Giardiasis can look (histologically) a lot like celiac disease.
*Celiac disease.<ref name=pmid11252408>{{cite journal |author=Murray IA, Smith JA, Coupland K, Ansell ID, Long RG |title=Intestinal disaccharidase deficiency without villous atrophy may represent early celiac disease |journal=Scand. J. Gastroenterol. |volume=36 |issue=2 |pages=163–8 |year=2001 |month=February |pmid=11252408 |doi= |url=}}</ref>


Images:
Notes:
*[http://commons.wikimedia.org/wiki/File:Giardiasis_duodenum_high.jpg Giardiasis - high mag. (WC)].
*May have normal histomorphology.<ref name=pmid2116456>{{cite journal |author=Langman JM, Rowland R |title=Activity of duodenal disaccharidases in relation to normal and abnormal mucosal morphology |journal=J. Clin. Pathol. |volume=43 |issue=7 |pages=537–40 |year=1990 |month=July |pmid=2116456 |pmc=502575 |doi= |url=}}</ref>
*[http://commons.wikimedia.org/wiki/File:Giardiasis_duodenum_low.jpg Giardiasis - low mag. (WC)].


===Treatment===
==Whipple disease==
*Antibiotics, e.g. metronidazole (Flagyl).
{{Main|Whipple's disease}}


==Whipple's disease==
==Microvillous inclusion disease==
===Epidemiology===
{{Main|Microvillous inclusion disease}}
*Very rare.
This rare disease presents very shortly after birth.  
*Classically middle aged men.


===Clinical===
==Tufting enteropathy==
*Malabsorption (diarrhea), arthritis + others.  
*[[AKA]] ''intestinal epithelial dysplasia''.
**Symptoms are non-specific.
===General===
*Genetic disease<ref name=omim613217>{{OMIM|613217}}</ref> - related to abnormal enterocytes (development and/or differentiation).
**Gene implicated: ''EPCAM''.<ref name=omim185535>{{OMIM|185535}}</ref>


===Etiology===
===Microscopic===
*Infection - caused by ''Tropheryma whipplei''.<ref>{{cite journal |author=Liang Z, La Scola B, Raoult D |title=Monoclonal antibodies to immunodominant epitope of Tropheryma whipplei |journal=Clin. Diagn. Lab. Immunol. |volume=9 |issue=1 |pages=156?9 |year=2002 |month=January |pmid=11777846 |pmc=119894 |doi= |url=http://cvi.asm.org/cgi/pmidlookup?view=long&pmid=11777846}}</ref>
Features:<ref name=pmid17448233>{{cite journal |author=Goulet O, Salomon J, Ruemmele F, de Serres NP, Brousse N |title=Intestinal epithelial dysplasia (tufting enteropathy) |journal=Orphanet J Rare Dis |volume=2 |issue= |pages=20 |year=2007 |pmid=17448233 |pmc=1878471 |doi=10.1186/1750-1172-2-20 |url=}}</ref>
*Villous atrophy
*Mononuclear cell infiltration of the lamina propria
*Abnormal surface enterocytes:
**Focal crowding -- resembling tufts.


===Histology===
Features:<ref>{{cite journal | author=Bai J, Mazure R, Vazquez H, Niveloni S, Smecuol E, Pedreira S, Mauriño E | title=Whipple's disease | journal=Clin Gastroenterol Hepatol | volume=2 | issue=10 | pages=849?60 | year=2004 | pmid=15476147  | doi=10.1016/S1542-3565(04)00387-8}}</ref>
*Infectious microorganism typically found in macrophages.
**Macrophages usually abundant - '''key feature''' that should raise Dx in DDx.
**Organisms periodic acid-Schiff (PAS) positive.


===Treatment===  
==Gangliocytic paraganglioma==
*Antibiotics - for months and months.
*Abbreviated ''GP''.
{{Main|Gangliocytic paraganglioma}}


Micrograph: [http://en.wikipedia.org/wiki/File:Whipple2.jpg Whipple's disease] - wikipedia.org.
==Pseudomelanosis duodeni==
{{Main|Pseudomelanosis duodeni}}


==Tumours==
=Tumours=
==Lymphoma==
==Lymphoma==
{{main|Lymphoma}}
{{main|Lymphoma}}
*Non-Hodgkin's lymphoma.
*Non-Hodgkin's lymphoma.
**Enteropathy-associated T-cell lymphoma (EATL) - due to ''celiac sprue''.
**[[Enteropathy-associated T-cell lymphoma]] (EATL) - due to ''[[celiac sprue]]''.
***Image: [http://commons.wikimedia.org/wiki/File:Enteropathy-associated_T_cell_lymphoma_-_low_mag.jpg EATL - low mag. (WC)].
**[[MALT lymphoma]] - common GI tract lymphoma.
**[[MALT lymphoma]] - common GI tract lymphoma.
**[[Mantle cell lymphoma]].
**[[Mantle cell lymphoma]].
Line 135: Line 275:
*[[Hodgkin's lymphoma]] does not arise in the GI tract.
*[[Hodgkin's lymphoma]] does not arise in the GI tract.


==Adenocarcinoma==
==Adenocarcinoma of the duodenum==
*Similar to large bowel adenocarcinomas (see ''[[colorectal tumours]]'' article).
*[[AKA]] ''duodenal adenocarcinoma''.
*Duodenum - most common site in small bowel.
*[[AKA]] ''duodenal carcinoma''.
 
{{Main|Adenocarcinoma of the duodenum}}
Risk factors:
*[[Crohn's disease]]
*[[Celiac disease]]
*[[FAP]]
*[[HNPCC]]
*[[Peutz-Jeghers syndrome]]


==Neuroendocrine tumours==
==Duodenal neuroendocrine tumour==
{{Main|Neuroendocrine tumours}}
:''Duodenal NET'' redirects here.
===General===
===General===
*Like neuroendocrine tumours elsewhere.
*Like [[neuroendocrine tumours]] elsewhere.
*Use of the term ''carcinoid'' is discouraged.<ref name=pmid18414708>{{Cite journal  | last1 = Chetty | first1 = R. | title = Requiem for the term 'carcinoid tumour' in the gastrointestinal tract? | journal = Can J Gastroenterol | volume = 22 | issue = 4 | pages = 357-8 | month = Apr | year = 2008 | doi =  | PMID = 18414708 }}
*Use of the term ''carcinoid'' is discouraged.<ref name=pmid18414708>{{Cite journal  | last1 = Chetty | first1 = R. | title = Requiem for the term 'carcinoid tumour' in the gastrointestinal tract? | journal = Can J Gastroenterol | volume = 22 | issue = 4 | pages = 357-8 | month = Apr | year = 2008 | doi =  | PMID = 18414708 }}
</ref><ref name=pmid15153416>{{Cite journal  | last1 = Klöppel | first1 = G. | last2 = Perren | first2 = A. | last3 = Heitz | first3 = PU. | title = The gastroenteropancreatic neuroendocrine cell system and its tumors: the WHO classification. | journal = Ann N Y Acad Sci | volume = 1014 | issue =  | pages = 13-27 | month = Apr | year = 2004 | doi =  | PMID = 15153416 }}
</ref><ref name=pmid15153416>{{Cite journal  | last1 = Klöppel | first1 = G. | last2 = Perren | first2 = A. | last3 = Heitz | first3 = PU. | title = The gastroenteropancreatic neuroendocrine cell system and its tumors: the WHO classification. | journal = Ann N Y Acad Sci | volume = 1014 | issue =  | pages = 13-27 | month = Apr | year = 2004 | doi =  | PMID = 15153416 }}
</ref><ref name=pmid14513276>{{cite journal |author=Klöppel G |title=[Neuroendocrine tumors of the gastrointestinal tract] |language=German |journal=Pathologe |volume=24 |issue=4 |pages=287–96 |year=2003 |month=July |pmid=14513276 |doi=10.1007/s00292-003-0636-7 |url=}}</ref>
</ref><ref name=pmid14513276>{{cite journal |author=Klöppel G |title=[Neuroendocrine tumors of the gastrointestinal tract] |language=German |journal=Pathologe |volume=24 |issue=4 |pages=287–96 |year=2003 |month=July |pmid=14513276 |doi=10.1007/s00292-003-0636-7 |url=}}</ref>
Associations:
*[[Neurofibromatosis type 1]].
*[[MEN I]].


===Microscopic===
===Microscopic===
Features:
Features:<ref>URL: [http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf]. Accessed on: 29 March 2012.</ref>
*Nests of cells.
*Usu. nests of cells - may be:
*Stippled chromatin - AKA: salt-and-pepper chromatin, coarse chromatin.
**[[Trabecular]].
**Glandular - common in stomatostatin producing tumours.
*Stippled chromatin - ([[AKA]] salt-and-pepper chromatin, coarse chromatin).
*Classically subepithelial/mural.
*Classically subepithelial/mural.
*+/-[[Psammoma bodies]] - suggestive of [[somatostatinoma]] and [[NF1]].<ref name=pmid21437171>{{Cite journal  | last1 = Kim | first1 = JA. | last2 = Choi | first2 = WH. | last3 = Kim | first3 = CN. | last4 = Moon | first4 = YS. | last5 = Chang | first5 = SH. | last6 = Lee | first6 = HR. | title = Duodenal somatostatinoma: a case report and review. | journal = Korean J Intern Med | volume = 26 | issue = 1 | pages = 103-7 | month = Mar | year = 2011 | doi = 10.3904/kjim.2011.26.1.103 | PMID = 21437171 }}</ref>


Images:
DDx:
*[http://commons.wikimedia.org/wiki/File:Small_intestine_neuroendocrine_tumour_low_mag.jpg Neuroendocrine tumour - low mag. (WC)].
*[[Adenocarcinoma of the duodenum]].
*[http://commons.wikimedia.org/wiki/File:Small_intestine_neuroendocrine_tumour_intermed_mag.jpg Neuroendocrine tumour - intermed. mag. (WC)].
 
*[http://commons.wikimedia.org/wiki/File:Small_intestine_neuroendocrine_tumour_high_mag.jpg Neuroendocrine tumour - high mag. (WC)].
====Images====
<gallery>
Image:Small_intestine_neuroendocrine_tumour_low_mag.jpg | Neuroendocrine tumour - low mag. (WC)
Image:Small_intestine_neuroendocrine_tumour_intermed_mag.jpg | Neuroendocrine tumour - intermed. mag. (WC)
Image:Small_intestine_neuroendocrine_tumour_high_mag.jpg | Neuroendocrine tumour - high mag. (WC)
</gallery>
 
===Sign out===
<pre>
Duodenum, Biopsy:
- Incidental neuroendocrine tumour, grade 1, see comment.
- Background small bowel mucosa with Brunner's glands within normal limits.
 
Comment:
The tumour stains as follows:
POSITIVE: AE1/AE3, CD56, synaptophysin.
NEGATIVE: S-100, CD68.
PROLIFERATION (Ki-67): <2%.
</pre>


==Ampullary tumours==
==Ampullary tumours==
{{Main|Ampullary tumours}}
===General===
*Individuals with high-grade dysplasia (on biopsy) are usually treated with a pancreaticoduodenectomy (Whipple procedure), as local resections have a very high recurrence rate.<ref name=pmid16332486>{{Cite journal  | last1 = Meneghetti | first1 = AT. | last2 = Safadi | first2 = B. | last3 = Stewart | first3 = L. | last4 = Way | first4 = LW. | title = Local resection of ampullary tumors. | journal = J Gastrointest Surg | volume = 9 | issue = 9 | pages = 1300-6 | month = Dec | year = 2005 | doi = 10.1016/j.gassur.2005.08.031 | PMID = 16332486 }}</ref>
===Microscopic===
Features:
*''See [[ampullary tumours]]''.
DDx:
*[[Intraductal papillary mucinous tumour]] (IPMT) - a pancreatic tumour, see ''[[pancreas]]'' article.
*[[Invasive ductal carcinoma of the pancreas]].
===Sign out===
*Ampullary carcinoma - has separate staging.
*Ampullary carcinoma - has separate staging.
*Intraductal papillary mucinous tumour (IPMT) - a pancreatic tumour, see ''[[pancreas]]'' article.


==See also==
==Traditional adenoma==
:''Duodenal adenoma'' redirects here.
{{Main|Traditional adenoma}}
===General===
*Strong association of [[familial adenomatous polyposis]].
**In one series of 208 adenomas, almost 70% were from FAP patients.<ref name=pmid16837629/>
*Commonly found in association foveolar metaplasia - especially in sporadic cases ~60% of cases.
**In FAP ~30% of cases have foveolar metaplasia.<ref name=pmid16837629>{{Cite journal  | last1 = Rubio | first1 = CA. | title = Gastric duodenal metaplasia in duodenal adenomas. | journal = J Clin Pathol | volume = 60 | issue = 6 | pages = 661-3 | month = Jun | year = 2007 | doi = 10.1136/jcp.2006.039388 | PMID = 16837629 | PMC = 1955048}}</ref>
*A colonscopy is recommended in individuals with nonampullary duodenal adenomas, as they are likely at increased risk of large bowel adenomas.<ref name=pmid26811631>{{Cite journal  | last1 = Lim | first1 = CH. | last2 = Cho | first2 = YS. | title = Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management. | journal = World J Gastroenterol | volume = 22 | issue = 2 | pages = 853-61 | month = Jan | year = 2016 | doi = 10.3748/wjg.v22.i2.853 | PMID = 26811631 }}</ref>
 
===Sign out===
<pre>
POLYP, DUODENUM, EXCISION:
- TUBULAR ADENOMA.
-- NEGATIVE FOR HIGH-GRADE DYSPLASIA.
</pre>
 
====Alternate====
<pre>
Polyp (Nonampullary), Duodenum, Polypectomy:
    - Tubular adenoma, NEGATIVE for high-grade dysplasia.
 
Comment:
A colonscopy is recommended if not done recently, as individual with nonampullary duodenal adenomas are likely at increased risk of large bowel adenomas.[1]
 
1. Therap Adv Gastroenterol. 2012 Mar; 5(2): 127138. doi: 10.1177/1756283X11429590
</pre>
 
=See also=
*[[Gastrointestinal pathology]].
*[[Gastrointestinal pathology]].
*[[Intestinal polyps]].
*[[Intestinal polyps]].
*[[Small bowel]].
*[[Small bowel]].


==References==
=References=
{{reflist|2}}
{{reflist|2}}


[[Category:Gastrointestinal pathology]]
[[Category:Gastrointestinal pathology]]
=External links=
===Review article(s)===
*{{cite journal |author=Serra S, Jani PA |title=An approach to duodenal biopsies |journal=J. Clin. Pathol. |volume=59 |issue=11 |pages=1133–50 |year=2006 |month=November |pmid=16679353 |pmc=1860495 |doi=10.1136/jcp.2005.031260 |url=http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860495/?tool=pubmed}}

Latest revision as of 14:28, 14 June 2024

Schematic of the duodenum. (WC/Luke Guthmann)

The duodenum is the first part of the small bowel and receives food from the stomach. It is accessible by EGD (esophagogastroduodenoscopy) and frequently biopsied.

An introduction to gastrointestinal pathology is in the gastrointestinal pathology article.

The clinical history is often: r/o celiac or r/o giardia.

Getting started

Normal duodenum

  • Abbreviated ND.

General

  • Very common.

Microscopic

  • Three tall villi.
  • Few intraepithelial lymphocytes; < 1 lymphocyte / 4 epithelial cells.
  • No (pink) subepithelial collagen band.
  • Predominant lamina propria cell: plasma cells.
  • No organisms in lumen.

DDx:

Sign out

Duodenum, Biopsy:
- Small bowel mucosa and Brunner's glands within normal limits.
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
Duodenum, Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.
Small Bowel (Duodenum), Biopsy:
- Small bowel mucosa within normal limits.
- NEGATIVE for findings suggestive of celiac disease.

Block letters

DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA AND BRUNNER'S GLANDS WITHIN NORMAL LIMITS.
DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
DUODENUM, BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.
SMALL BOWEL (DUODENUM), BIOPSY: 
- SMALL BOWEL MUCOSA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FINDINGS SUGGESTIVE OF CELIAC DISEASE.

Basic DDx

  • Celiac sprue.
    • Intraepithelial lymphocytes - key feature.
    • Loss of villi.
  • Giardia.
    • Like celiac... but giardia organisms.
  • Adenomas.
    • Too much blue - similar to colonic adenomas.
  • Cancer.
    • Too much blue and epithelium in the wrong place.

More

Duodenal nodules DDX

 
 
 
 
 
 
 
 
 
 
 
 
Duodenal
nodule
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Benign
(common)
 
 
 
 
 
 
 
 
 
 
 
 
 
Neoplastic
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Brunner's
gland
 
Heterotopic
gastric mucosa
 
Lymphoid
nodule
 
Adenoma
 
NET
 
Paraganglioma
 
Prolapsed
gastric polyp
 
Metastasis
 
 
 
 

Infections of the duodenum[3]

Common:

Rare:

Common stuffs

Gastric heterotopia of the duodenum

  • AKA heterotopic gastric mucosa.

Celiac sprue

  • AKA celiac disease.

Giardiasis

Acute duodenitis

  • Abbreviated AD.

Chronic duodenitis

General

  • This is not very well defined as plasma cells are present in a normal duodenum.

Gross

  • Duodenal erythema.

Microscopic

Features:

DDx:

Sign out

DUODENUM, BIOPSY:
- MODERATE NON-SPECIFIC CHRONIC DUODENTIS (SMALL BOWEL MUCOSA WITH VILLOUS
  BLUNTING, PROMINENT BRUNNER'S GLANDS, ABUNDANT LAMINA PROPRIA PLASMA CELLS
  AND OCCASIONAL INTRAEPITHELIAL LYMPHOCYTES, WITHOUT FOVEOLAR METAPLASIA).
- NEGATIVE FOR DYSPLASIA.

Peptic duodenitis

Brunner's gland hyperplasia

Brunner's gland hamartoma redirects here.
  • Abbreviated BGH.
  • AKA Brunneroma.[4]

General

  • Benign.
  • Usually asymptomatic.[5]

Note:

  • The AFIP uses the term Brunner's gland hamartoma for lesions > 5 mm.[6]
    • Multiple lesions less than 5 mm are hyperplasia.

Gross

  • Nodularity of the duodenum.

Microscopic

Features:

  • Prominent Brunner's gland.
    • Tubular structures - formed by cells abundant cytoplasm that is clear with eosinophilic "cobwebs" and a round, small basal nucleus without a nucleolus.
    • Brunner's glands close to the surface epithelium - key feature.[7]
  • +/-Pancreatic acini and ducts.[6]

DDx:

Image:

Sign out

DUODENUM, BIOPSY:
- CONSISTENT WITH BRUNNER'S GLAND HYPERPLASIA.
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
 DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITHOUT SIGNIFICANT PATHOLOGY.
- PROMINENT BRUNNER'S GLANDS WITH EXTENSION INTO THE LAMINA PROPRIA.

Superficial Brunner's glands

DUODENUM, BIOPSY:
- SMALL BOWEL MUCOSA WITH BRUNNER'S GLANDS THAT ARE FOCALLY SUPERFICIAL.
- NO FINDINGS SUGGESTIVE OF CELIAC DISEASE.
- NEGATIVE FOR ACTIVE INFLAMMATION.
- NEGATIVE FOR DYSPLASIA.

Micro

The sections show small bowel mucosa and a small amount of submucosa. Brunner's glands are abundant and found focally in the lamina propria.

The epithelium matures appropriately. There is no increase in intraepithelial lymphocytes. No foveolar metaplasia of the epithelium is identified.

Helicobacter duodenitis

  • Helicobacter is the most common cause of duodenitis.[8][9]
  • Overall, Helicobacter is rare in the duodenum.

Sign out

A. Duodenum, Biopsy:
	- Active duodenitis associated with foveolar epithelium and HELICOBACTER-LIKE ORGANISMS.
	- NEGATIVE for dysplasia.

Weird stuff

Disaccharidases deficiency

General

  • Common among asians.
  • Includes: lactase, sucrase, and maltase.
    • Lactase changes seen with mild histomorphologic changes.[11]
    • Maltase and sucrase only affected in moderate and severe lesions.

Microscopic

Features:[11]

  • Decreased villous-crypt ratio (mild to severe).
  • +/-Inflammation (only in moderate and severe).

DDx:

Notes:

  • May have normal histomorphology.[11]

Whipple disease

Microvillous inclusion disease

This rare disease presents very shortly after birth.

Tufting enteropathy

  • AKA intestinal epithelial dysplasia.

General

  • Genetic disease[13] - related to abnormal enterocytes (development and/or differentiation).
    • Gene implicated: EPCAM.[14]

Microscopic

Features:[15]

  • Villous atrophy
  • Mononuclear cell infiltration of the lamina propria
  • Abnormal surface enterocytes:
    • Focal crowding -- resembling tufts.


Gangliocytic paraganglioma

  • Abbreviated GP.

Pseudomelanosis duodeni

Tumours

Lymphoma

Note:

Adenocarcinoma of the duodenum

  • AKA duodenal adenocarcinoma.
  • AKA duodenal carcinoma.

Duodenal neuroendocrine tumour

Duodenal NET redirects here.

General

Associations:

Microscopic

Features:[19]

  • Usu. nests of cells - may be:
    • Trabecular.
    • Glandular - common in stomatostatin producing tumours.
  • Stippled chromatin - (AKA salt-and-pepper chromatin, coarse chromatin).
  • Classically subepithelial/mural.
  • +/-Psammoma bodies - suggestive of somatostatinoma and NF1.[20]

DDx:

Images

Sign out

Duodenum, Biopsy:
	- Incidental neuroendocrine tumour, grade 1, see comment.
	- Background small bowel mucosa with Brunner's glands within normal limits.

Comment:
The tumour stains as follows:
POSITIVE: AE1/AE3, CD56, synaptophysin.
NEGATIVE: S-100, CD68.
PROLIFERATION (Ki-67): <2%.

Ampullary tumours

General

  • Individuals with high-grade dysplasia (on biopsy) are usually treated with a pancreaticoduodenectomy (Whipple procedure), as local resections have a very high recurrence rate.[21]

Microscopic

Features:

DDx:

Sign out

  • Ampullary carcinoma - has separate staging.

Traditional adenoma

Duodenal adenoma redirects here.

General

  • Strong association of familial adenomatous polyposis.
    • In one series of 208 adenomas, almost 70% were from FAP patients.[22]
  • Commonly found in association foveolar metaplasia - especially in sporadic cases ~60% of cases.
    • In FAP ~30% of cases have foveolar metaplasia.[22]
  • A colonscopy is recommended in individuals with nonampullary duodenal adenomas, as they are likely at increased risk of large bowel adenomas.[23]

Sign out

POLYP, DUODENUM, EXCISION:
- TUBULAR ADENOMA.
-- NEGATIVE FOR HIGH-GRADE DYSPLASIA.

Alternate

Polyp (Nonampullary), Duodenum, Polypectomy:
     - Tubular adenoma, NEGATIVE for high-grade dysplasia.

Comment:
A colonscopy is recommended if not done recently, as individual with nonampullary duodenal adenomas are likely at increased risk of large bowel adenomas.[1]

1. Therap Adv Gastroenterol. 2012 Mar; 5(2): 127138. doi: 10.1177/1756283X11429590

See also

References

  1. Agarwal S, Smereka P, Harpaz N, Cunningham-Rundles C, Mayer L (July 2010). "Characterization of immunologic defects in patients with common variable immunodeficiency (CVID) with intestinal disease". Inflamm Bowel Dis. doi:10.1002/ibd.21376. PMID 20629103.
  2. El-Zimaity. 18 October 2010.
  3. Serra S, Jani PA (November 2006). "An approach to duodenal biopsies". J. Clin. Pathol. 59 (11): 1133–50. doi:10.1136/jcp.2005.031260. PMC 1860495. PMID 16679353. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860495/?tool=pubmed.
  4. Tan, YM.; Wong, WK. (2002). "Giant Brunneroma as an unusual cause of upper gastrointestinal hemorrhage: report of a case.". Surg Today 32 (10): 910-2. doi:10.1007/s005950200179. PMID 12376792.
  5. 5.0 5.1 Lee, WC.; Yang, HW.; Lee, YJ.; Jung, SH.; Choi, GY.; Go, H.; Kim, A.; Cha, SW. (Jun 2008). "Brunner's gland hyperplasia: treatment of severe diffuse nodular hyperplasia mimicking a malignancy on pancreatic-duodenal area.". J Korean Med Sci 23 (3): 540-3. doi:10.3346/jkms.2008.23.3.540. PMID 18583897.
  6. 6.0 6.1 6.2 Patel, ND.; Levy, AD.; Mehrotra, AK.; Sobin, LH. (Sep 2006). "Brunner's gland hyperplasia and hamartoma: imaging features with clinicopathologic correlation.". AJR Am J Roentgenol 187 (3): 715-22. doi:10.2214/AJR.05.0564. PMID 16928936.
  7. Franzin, G.; Musola, R.; Ghidini, O.; Manfrini, C.; Fratton, A. (Dec 1985). "Nodular hyperplasia of Brunner's glands.". Gastrointest Endosc 31 (6): 374-8. PMID 4076734.
  8. URL: https://www.saintlukeskc.org/health-library/duodenitis. Accessed on: 2024 Feb 5.
  9. URL: https://www.webmd.com/digestive-disorders/what-is-duodenitis. Accessed on: 2024 Feb 5.
  10. Yang H, Dixon MF, Zuo J, Fong F, Zhou D, Corthésy I, Blum A (March 1995). "Helicobacter pylori infection and gastric metaplasia in the duodenum in China". J Clin Gastroenterol 20 (2): 110–2. doi:10.1097/00004836-199503000-00007. PMID 7769188.
  11. 11.0 11.1 11.2 Langman JM, Rowland R (July 1990). "Activity of duodenal disaccharidases in relation to normal and abnormal mucosal morphology". J. Clin. Pathol. 43 (7): 537–40. PMC 502575. PMID 2116456. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC502575/.
  12. Murray IA, Smith JA, Coupland K, Ansell ID, Long RG (February 2001). "Intestinal disaccharidase deficiency without villous atrophy may represent early celiac disease". Scand. J. Gastroenterol. 36 (2): 163–8. PMID 11252408.
  13. Online 'Mendelian Inheritance in Man' (OMIM) 613217
  14. Online 'Mendelian Inheritance in Man' (OMIM) 185535
  15. Goulet O, Salomon J, Ruemmele F, de Serres NP, Brousse N (2007). "Intestinal epithelial dysplasia (tufting enteropathy)". Orphanet J Rare Dis 2: 20. doi:10.1186/1750-1172-2-20. PMC 1878471. PMID 17448233. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1878471/.
  16. Chetty, R. (Apr 2008). "Requiem for the term 'carcinoid tumour' in the gastrointestinal tract?". Can J Gastroenterol 22 (4): 357-8. PMID 18414708.
  17. Klöppel, G.; Perren, A.; Heitz, PU. (Apr 2004). "The gastroenteropancreatic neuroendocrine cell system and its tumors: the WHO classification.". Ann N Y Acad Sci 1014: 13-27. PMID 15153416.
  18. Klöppel G (July 2003). "[Neuroendocrine tumors of the gastrointestinal tract]" (in German). Pathologe 24 (4): 287–96. doi:10.1007/s00292-003-0636-7. PMID 14513276.
  19. URL: http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SmallbowelNET_11protocol.pdf. Accessed on: 29 March 2012.
  20. Kim, JA.; Choi, WH.; Kim, CN.; Moon, YS.; Chang, SH.; Lee, HR. (Mar 2011). "Duodenal somatostatinoma: a case report and review.". Korean J Intern Med 26 (1): 103-7. doi:10.3904/kjim.2011.26.1.103. PMID 21437171.
  21. Meneghetti, AT.; Safadi, B.; Stewart, L.; Way, LW. (Dec 2005). "Local resection of ampullary tumors.". J Gastrointest Surg 9 (9): 1300-6. doi:10.1016/j.gassur.2005.08.031. PMID 16332486.
  22. 22.0 22.1 Rubio, CA. (Jun 2007). "Gastric duodenal metaplasia in duodenal adenomas.". J Clin Pathol 60 (6): 661-3. doi:10.1136/jcp.2006.039388. PMC 1955048. PMID 16837629. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1955048/.
  23. Lim, CH.; Cho, YS. (Jan 2016). "Nonampullary duodenal adenoma: Current understanding of its diagnosis, pathogenesis, and clinical management.". World J Gastroenterol 22 (2): 853-61. doi:10.3748/wjg.v22.i2.853. PMID 26811631.

External links

Review article(s)