Editing Gluten (section)

===Celiac disease===
{{Main article|Coeliac disease}}
[[File:Inflammed mucous layer of the intestinal villi depicting Celiac disease.jpg|thumb|Medical animation still showing flattened intestinal villi.]]
[[Celiac disease]] (CD) is a chronic, multiple-organ [[autoimmune disorder]] primarily affecting the [[small intestine]] caused by the ingestion of wheat, barley, rye, oats, and derivatives, that appears in [[genetic predisposition|genetically predisposed]] people of all ages.<ref name=":0">{{Cite journal|last1=Caio|first1=Giacomo|last2=Volta|first2=Umberto|last3=Sapone|first3=Anna|last4=Leffler|first4=Daniel A.|last5=De Giorgio|first5=Roberto|last6=Catassi|first6=Carlo|last7=Fasano|first7=Alessio|date=2019-07-23|title=Celiac disease: a comprehensive current review|journal=BMC Medicine|volume=17|issue=1|pages=142|doi=10.1186/s12916-019-1380-z |pmid=31331324|pmc=6647104 |doi-access=free }}</ref> CD is not only a gastrointestinal disease, because it may involve several organs and cause an extensive variety of non-gastrointestinal symptoms, and most importantly, it may be apparently asymptomatic.<ref name=Biesiekierski2017 /><ref name=WGO2016>{{cite web|url=http://www.worldgastroenterology.org/guidelines/global-guidelines/celiac-disease/celiac-disease-english|title=Celiac disease|date=July 2016|publisher=[[World Gastroenterology Organisation]] Global Guidelines|access-date=23 April 2017}}</ref> Many asymptomatic people become accustomed to living with a chronic bad health status as if it were normal, but they are able to recognize that they actually had symptoms related to celiac disease after starting a gluten-free diet and improvement occurs.<ref name=WGO2016 /><ref name=LudvigssonCard /><ref name=LionettiGatti2015 /> Added difficulties for diagnosis are the fact that serological markers ([[Anti-transglutaminase antibodies#Anti-tissue transglutaminase|anti-tissue transglutaminase]] [TG2]) are not always present<ref name=NEJM2012>{{cite journal|last1=Fasano|first1=A|last2=Catassi|first2=C|title=Clinical practice. Celiac disease.|journal=The New England Journal of Medicine|date=December 2012|volume=367|issue=25|pages=2419–26|pmid=23252527|doi=10.1056/NEJMcp1113994}}</ref> and many people may have minor mucosal lesions, without atrophy of the [[intestinal villi]].<ref name=BoldRostami>{{cite journal | vauthors = Bold J, Rostami K| title = Gluten tolerance; potential challenges in treatment strategies | journal = Gastroenterol Hepatol Bed Bench | volume = 4| issue = 2| pages = 53–7| date = 2011 | pmid = 24834157|pmc= 4017406}}</ref>

CD affects approximately 1–2% of the general population,<ref name=LundinWijmenga2015>{{cite journal|vauthors=Lundin KE, Wijmenga C|title=Coeliac disease and autoimmune disease-genetic overlap and screening|journal=Nat Rev Gastroenterol Hepatol|volume=12|issue=9|pages=507–15|date =Sep 2015|pmid=26303674|doi=10.1038/nrgastro.2015.136|s2cid=24533103}}</ref> but most cases remain unrecognized, undiagnosed and untreated, and at risk for serious long-term health complications.<ref name=LundinWijmenga2015 /><ref name=LionettiGatti2015 /><ref name=Fasano2005Pediatric>{{cite journal | author = Fasano A| title = Clinical presentation of celiac disease in the pediatric population | journal = Gastroenterology | volume = 128| issue = 4 Suppl 1| pages = S68–73| date = Apr 2005| pmid = 15825129 | doi = 10.1053/j.gastro.2005.02.015}}</ref><ref name=ElliBranchi>{{cite journal | vauthors = Elli L, Branchi F, Tomba C, Villalta D, Norsa L, Ferretti F, Roncoroni L, Bardella MT| title = Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity | journal = World J Gastroenterol | volume = 21 | issue = 23 | pages = 7110–9 | date = Jun 2015 | pmid = 26109797 |pmc= 4476872 | doi =  10.3748/wjg.v21.i23.7110 | doi-access = free }}</ref> People may suffer severe disease symptoms and be subjected to extensive investigations for many years, before a proper diagnosis is achieved.<ref name=LudvigssonCard>{{cite journal | vauthors = Ludvigsson JF, Card T, Ciclitira PJ, Swift GL, Nasr I, Sanders DS, Ciacci C| title = Support for patients with celiac disease: A literature review | journal = United European Gastroenterol J | volume = 3 | issue = 2 | pages = 146–59 | date = Apr 2015 | pmid = 25922674 | pmc = 4406900 |doi = 10.1177/2050640614562599}}</ref> Untreated CD may cause [[malabsorption]], reduced quality of life, [[iron deficiency]], [[osteoporosis]], an increased risk of intestinal [[lymphoma]]s, and greater mortality.<ref name=LebwoholLudvigsson>{{cite journal | vauthors =Lebwohl B, Ludvigsson JF, Green PH | title = Celiac disease and non-celiac gluten sensitivity | journal = BMJ | volume = 351 | pages = h4347| date = Oct 2015 | pmid = 26438584|pmc= 4596973 | doi = 10.1136/bmj.h4347|type= Review }}</ref> CD is associated with some other autoimmune diseases, such as [[diabetes mellitus type 1]], [[thyroiditis]],<ref name=LundinWijmenga>{{cite journal | vauthors = Lundin KE, Wijmenga C| title = Coeliac disease and autoimmune disease-genetic overlap and screening| journal = Nat Rev Gastroenterol Hepatol| volume = 12| issue = 9| pages = 507–15| date = Sep 2015 | pmid = 26303674 | doi = 10.1038/nrgastro.2015.136| s2cid = 24533103}}</ref> [[ataxia|gluten ataxia]], [[psoriasis]], [[vitiligo]], [[autoimmune hepatitis]], [[dermatitis herpetiformis]], [[primary sclerosing cholangitis]], and more.<ref name=":0" /><ref name=LundinWijmenga />

CD with "classic symptoms", which include gastrointestinal manifestations such as chronic diarrhea and abdominal distention, malabsorption, loss of appetite, and impaired growth, is currently the least common presentation form of the disease and affects predominantly small children generally younger than two years of age.<ref name=":0" /><ref name=LudvigssonCard /><ref name=Fasano2005Pediatric />

CD with "non-classic symptoms" is the most common clinical type<ref name=LudvigssonCard /> and occurs in older children (over two years old),<ref name=LudvigssonCard /> adolescents, and adults.<ref name=LudvigssonCard /> It is characterized by milder or even absent gastrointestinal symptoms and a wide spectrum of non-intestinal manifestations that can involve any organ of the body, and very frequently may be completely asymptomatic<ref name=Fasano2005Pediatric /> both in children (at least in 43% of the cases<ref name=VriezingaSchweizer>{{cite journal |vauthors=Vriezinga SL, Schweizer JJ, Koning F, Mearin ML |title=Coeliac disease and gluten-related disorders in childhood |journal=Nature Reviews. Gastroenterology & Hepatology |volume= 12 |issue= 9 |pages= 527–36 |date= Sep 2015 |pmid=26100369 |doi=10.1038/nrgastro.2015.98 |s2cid=2023530 |type=Review}}</ref>) and adults.<ref name=Fasano2005Pediatric />

Asymptomatic CD (ACD) is present in the majority of affected patients and is characterized by the absence of classical gluten-intolerance signs, such as diarrhea, bloating, and abdominal pain. Nevertheless, these individuals very often develop diseases that can be related with gluten intake. Gluten can be degraded into several morphine-like substances, named [[gluten exorphin]]s. These compounds have proven opioid effects and could mask the deleterious effects of gluten protein on gastrointestinal lining and function.<ref>{{cite journal |last1=Pruimboom |first1=Leo |last2=de Punder |first2=Karin |title=The opioid effects of gluten exorphins: asymptomatic celiac disease |journal=Journal of Health, Population, and Nutrition |date=24 November 2015 |volume=33 |page=24 |doi=10.1186/s41043-015-0032-y |pmid=26825414 |pmc=5025969 | type=Review |doi-access=free }}</ref>