View source for Gastroenteritis

{{Short description|Inflammation of the stomach and small intestine}}
{{cs1 config|name-list-style=vanc}}
{{Good article}}
{{Infobox medical condition (new)
| name            = Gastroenteritis
| image           = Gastroenteritis viruses.jpg
| caption         = Gastroenteritis viruses: A = rotavirus, B = adenovirus, C = norovirus and D = astrovirus. The virus particles are shown at the same magnification to allow size comparison.
| field           = [[Infectious disease (medical specialty)|Infectious disease]], [[gastroenterology]]
| synonyms        = Gastro, stomach bug, stomach virus, stomach flu, gastric flu, gastrointestinitis, flu bug
| symptoms        = [[Diarrhea]], [[vomiting]], [[abdomen|abdominal]] pain, [[fever]]<ref name=EBMED2010/><ref name=Ci2013/>
| complications   = [[Dehydration]]<ref name=Ci2013/><ref name=Fer2015/>
| onset           =
| duration        =
| causes          = [[Viruses]], [[bacteria]], [[parasites]], [[fungus|fungi]]<ref name=Ci2013/><ref name=Helm2006/>
| risks           =
| diagnosis       = Based on symptoms, occasionally [[stool culture]]<ref name=Ci2013/>
| differential    = [[Inflammatory bowel disease]], [[malabsorption syndrome]], [[lactose intolerance]]<ref>{{cite book|last1=Caterino|first1=Jeffrey M.|last2=Kahan|first2=Scott|title=In a Page: Emergency medicine|date=2003|publisher=Lippincott Williams & Wilkins|isbn=978-1-4051-0357-2|page=293|url=https://books.google.com/books?id=O0LwFPZDKbsC&pg=PA293|language=en|url-status=live|archive-url=https://web.archive.org/web/20170908184604/https://books.google.com/books?id=O0LwFPZDKbsC&pg=PA293|archive-date=2017-09-08}}</ref>
| prevention      = [[Hand washing]], drinking [[clean water]], proper disposal of [[human waste]], [[breastfeeding]]<ref name=Ci2013/>
| treatment       = [[Oral rehydration solution]] (combination of water, salts, and sugar), [[intravenous fluids]]<ref name=Ci2013/>
| medication      =
| prognosis       =
| frequency       = 2.4 billion (2015)<!-- incidence table --><ref name=GBD2015Pre/>
| deaths          = 1.3 million (2015)<ref name=GBD2015De/>
}}

'''Gastroenteritis''', also known as '''infectious diarrhea''', is an [[inflammation]] of the [[Human gastrointestinal tract|gastrointestinal tract]] including the [[stomach]] and [[intestine]].<ref name="Sch2015">{{cite book|last1=Schlossberg|first1=David|title=Clinical infectious disease|date=2015|isbn=978-1-107-03891-2|page=334|publisher=Cambridge University Press |edition=Second|url=https://books.google.com/books?id=meFwBwAAQBAJ&pg=PA334|url-status=live|archive-url=https://web.archive.org/web/20170908184604/https://books.google.com/books?id=meFwBwAAQBAJ&pg=PA334|archive-date=2017-09-08}}</ref> Symptoms may include [[diarrhea]], [[vomiting]], and [[abdominal pain]].<ref name="EBMED2010">{{cite journal|last=Singh|first=Amandeep|title=Pediatric Emergency Medicine Practice Acute Gastroenteritis — An Update|journal=Pediatric Emergency Medicine Practice|date=July 2010|volume=7|issue=7|url=http://www.ebmedicine.net/topics.php?paction=showTopic&topic_id=229}}</ref> [[Fever]], lack of energy, and [[dehydration]] may also occur.<ref name=Ci2013/><ref name="Fer2015">{{cite book|title=Ferri's Clinical Advisor 2015: 5 Books in 1|date=2014|publisher=Elsevier Health Sciences|isbn=978-0-323-08430-7|page=479|url=https://books.google.com/books?id=icTsAwAAQBAJ&pg=PA479|url-status=live|archive-url=https://web.archive.org/web/20170908184604/https://books.google.com/books?id=icTsAwAAQBAJ&pg=PA479|archive-date=2017-09-08}}</ref> This typically lasts less than two weeks.<ref name=Sch2015/> Although it is not related to [[influenza]], in the U.S it is sometimes called the "'''stomach flu'''".<ref>{{cite book|last1=Shors|first1=Teri|title=The microbial challenge: a public health perspective|date=2013|publisher=Jones & Bartlett Learning|location=Burlington, MA|isbn=978-1-4496-7333-8|page=457|edition=3rd|url=https://books.google.com/books?id=TDcvAqyx7AIC&pg=PA457|url-status=live|archive-url=https://web.archive.org/web/20170908184604/https://books.google.com/books?id=TDcvAqyx7AIC&pg=PA457|archive-date=2017-09-08}}</ref>

Gastroenteritis is usually caused by [[viruses]];<ref name="Helm2006" /> however, gut [[bacteria]], [[parasites]], and [[fungus|fungi]] can also cause gastroenteritis.<ref name="Ci2013" /><ref name="Helm2006">{{cite book|url=https://books.google.com/books?id=aVmRWrknaWgC&pg=PA2003|title=Textbook of therapeutics: drug and disease management|last1=A. Helms|first1=Richard|date=2006|publisher=Lippincott Williams & Wilkins|isbn=978-0-7817-5734-8|edition=8|location=Philadelphia [u.a.]|page=2003|archive-url=https://web.archive.org/web/20170908184604/https://books.google.com/books?id=aVmRWrknaWgC&pg=PA2003|archive-date=2017-09-08|url-status=live}}</ref> In children, [[rotavirus]] is the most common cause of severe disease.<ref name="Rota2012">{{cite journal |vauthors=Tate JE, Burton AH, Boschi-Pinto C, Steele AD, Duque J, Parashar UD |title=2008 estimate of worldwide rotavirus-associated mortality in children younger than 5 years before the introduction of universal rotavirus vaccination programmes: a systematic review and meta-analysis |journal=The Lancet Infectious Diseases |volume=12 |issue=2 |pages=136–41 |date=February 2012 |pmid=22030330 |doi=10.1016/S1473-3099(11)70253-5 |url=https://zenodo.org/record/1260248 }}</ref> In adults, [[norovirus]] and ''[[Campylobacter]]'' are common causes.<ref name="pmid21695033">{{cite journal |vauthors=Marshall JA, Bruggink LD |title=The dynamics of norovirus outbreak epidemics: recent insights |journal=International Journal of Environmental Research and Public Health |volume=8 |issue=4 |pages=1141–9 |date=April 2011 |pmid=21695033 |pmc=3118882 |doi=10.3390/ijerph8041141|doi-access=free }}</ref><ref name="pmid22025030">{{cite journal |author=Man SM |title=The clinical importance of emerging Campylobacter species |journal=Nature Reviews Gastroenterology & Hepatology |volume=8 |issue=12 |pages=669–85 |date=December 2011 |pmid=22025030 |doi=10.1038/nrgastro.2011.191|s2cid=24103030 }}</ref> Eating improperly prepared food, drinking contaminated water or close contact with a person who is infected can [[#Transmission|spread the disease]].<ref name=Ci2013/> Treatment is generally the same with or without a definitive diagnosis, so testing to confirm is usually not needed.<ref name=Ci2013/>

For young children in impoverished countries, prevention includes [[hand washing]] with soap, drinking [[clean water]], [[breastfeeding]] babies instead of using [[infant formula|formula]],<ref name=Ci2013/> and proper disposal of [[human waste]]. The [[rotavirus vaccine]] is recommended as a prevention for children.<ref name=Ci2013/><ref name=Rota2012/> Treatment involves getting enough fluids.<ref name=Ci2013/> For mild or moderate cases, this can typically be achieved by drinking [[oral rehydration solution]] (a combination of water, salts and sugar).<ref name=Ci2013/> In those who are breastfed, continued breastfeeding is recommended.<ref name=Ci2013/> For more severe cases, [[intravenous fluids]] may be needed.<ref name=Ci2013/> Fluids may also be given by a [[nasogastric tube]].<ref name="Webb2005">{{cite journal|last=Webb|first=A|author2=Starr, M|title=Acute gastroenteritis in children.|journal=Australian Family Physician|date=April 2005 |volume=34|issue=4|pages=227–31|pmid=15861741}}</ref> [[Zinc]] supplementation is recommended in children.<ref name="Ci2013">{{cite journal|last1=Ciccarelli|first1=S|last2=Stolfi|first2=I|last3=Caramia|first3=G|title=Management strategies in the treatment of neonatal and pediatric gastroenteritis.|journal=[[Infection and Drug Resistance]]|date=29 October 2013|volume=6|pages=133–61|pmid=24194646|doi=10.2147/IDR.S12718|pmc=3815002|doi-access=free}}</ref> [[Antibiotic]]s are generally not needed.<ref>{{cite journal |last1=Zollner-Schwetz |first1=I |last2=Krause |first2=R |date=August 2015 |title=Therapy of acute gastroenteritis: role of antibiotics. |journal=Clinical Microbiology and Infection |volume=21 |issue=8 |pages=744–9 |doi=10.1016/j.cmi.2015.03.002 |pmid=25769427 |doi-access=free}}</ref> However, antibiotics are recommended for young children with a fever and bloody diarrhea.<ref name=EBMED2010/>

In 2015, there were two billion cases of gastroenteritis, resulting in 1.3&nbsp;million deaths globally.<ref name="GBD2015Pre">{{cite journal|vauthors=((GBD 2015 Disease and Injury Incidence and Prevalence Collaborators))|title=Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015.|journal=Lancet|date=8 October 2016|volume=388|issue=10053|pages=1545–1602|pmid=27733282|doi=10.1016/S0140-6736(16)31678-6|pmc=5055577}}</ref><ref name="GBD2015De">{{cite journal|vauthors=((GBD 2015 Mortality and Causes of Death Collaborators))|title=Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: a systematic analysis for the Global Burden of Disease Study 2015.|journal=Lancet|date=8 October 2016|volume=388|issue=10053|pages=1459–1544|pmid=27733281|doi=10.1016/s0140-6736(16)31012-1|pmc=5388903}}</ref> Children and those in the [[developing world]] are affected the most.<ref name="Web09">{{cite book|last=Webber|first=Roger|title=Communicable disease epidemiology and control : a global perspective|year=2009|publisher=Cabi|location=Wallingford, Oxfordshire|isbn=978-1-84593-504-7|page=79|url=https://books.google.com/books?id=pZ9fpHtvOGYC&pg=PA79|edition=3rd|url-status=live|archive-url=https://web.archive.org/web/20151026161644/https://books.google.com/books?id=pZ9fpHtvOGYC&pg=PA79|archive-date=2015-10-26}}</ref> In 2011, there were about 1.7&nbsp;billion cases, resulting in about 700,000 deaths of children under the age of five.<ref name="Walk2013">{{cite journal|last=Walker|first=CL|author2=Rudan, I |author3=Liu, L |author4=Nair, H |author5=Theodoratou, E |author6=Bhutta, ZA |author7=O'Brien, KL |author8=Campbell, H |author9= Black, RE  |title=Global burden of childhood pneumonia and diarrhoea.|journal=Lancet|date=Apr 20, 2013|volume=381|issue=9875|pages=1405–16|pmid=23582727|doi=10.1016/S0140-6736(13)60222-6|pmc=7159282}}</ref> In the developing world, children less than two years of age frequently get six or more infections a year.<ref name="M93">{{cite book |chapter=Chapter 93 |editor1-last=Dolin |editor1-first=Raphael |editor2-last=Mandell |editor2-first=Gerald L. |editor3-last=Bennett |editor3-first=John E. |year=2010 |title=Mandell, Douglas, and Bennett's principles and practice of infectious diseases|publisher=Churchill Livingstone/Elsevier|location=Philadelphia|isbn=978-0-443-06839-3|edition=7th}}</ref> It is less common in adults, partly due to the development of [[immunity (medical)|immunity]].<ref name="Eck2011">{{cite journal |vauthors=Eckardt AJ, Baumgart DC |title=Viral gastroenteritis in adults |journal=Recent Patents on Anti-Infective Drug Discovery |volume=6 |issue=1 |pages=54–63 |date=January 2011 |pmid=21210762 |doi=10.2174/157489111794407877}}</ref>

==Signs and symptoms==
[[File:BristolStoolChart.png|thumb|upright=1.7|[[Bristol stool scale|Bristol stool chart]]]]
Gastroenteritis usually involves both [[diarrhea]] and [[vomiting]].<ref name=Eck2011/> Sometimes, only one or the other is present.<ref name=EBMED2010/> This may be accompanied by abdominal cramps.<ref name=EBMED2010/> Signs and symptoms usually begin 12–72&nbsp;hours after contracting the infectious agent.<ref name="Web09" /> If due to a virus, the condition usually resolves within one week.<ref name=Eck2011/> Some viral infections also involve [[fever]], fatigue, [[headache]] and [[myalgia|muscle pain]].<ref name=Eck2011/> If the [[dysentery|stool is bloody]], the cause is less likely to be viral<ref name=Eck2011/> and more likely to be bacterial.<ref name=Bact2007/> Some bacterial infections cause severe abdominal pain and may persist for several weeks.<ref name=Bact2007/>

Children infected with rotavirus usually make a full recovery within three to eight days.<ref name="Rota2011">{{cite journal|last=Meloni|first=A|author2=Locci, D |author3=Frau, G |author4=Masia, G |author5=Nurchi, AM |author6=Coppola, RC |title=Epidemiology and prevention of rotavirus infection: an underestimated issue?|journal=Journal of Maternal-Fetal and Neonatal Medicine|date=October 2011 |volume=24 |issue=Suppl 2|pages=48–51|pmid=21749188|doi=10.3109/14767058.2011.601920|s2cid=44379279}}</ref> However, in poor countries treatment for severe infections is often out of reach and persistent diarrhea is common.<ref>{{cite web|title=Toolkit |url=http://www.defeatdd.org/understanding-crisis/advocacy-outreach/toolkits |work=DefeatDD |access-date=3 May 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120427053802/http://www.defeatdd.org/understanding-crisis/advocacy-outreach/toolkits |archive-date=27 April 2012 }}</ref>  [[Dehydration]] is a common complication of [[diarrhea]].<ref name="NICE2009">{{cite web|title=Management of acute diarrhoea and vomiting due to gastoenteritis in children under 5|url=http://guidance.nice.org.uk/CG84|work=National Institute of Clinical Excellence|date=April 2009|url-status=dead|archive-url=https://web.archive.org/web/20090802094158/http://guidance.nice.org.uk/CG84|archive-date=2009-08-02|access-date=2009-06-11}}</ref> Severe dehydration in children may be recognized if the skin color and position returns slowly when pressed.<ref name=Tint10/> This is called "prolonged [[capillary refill]]" and "poor [[skin turgor]]".<ref name=Tint10/> Abnormal breathing is another sign of severe dehydration.<ref name="Tint10">{{cite book |author=Tintinalli, Judith E. |title=Emergency Medicine: A Comprehensive Study Guide (Emergency Medicine (Tintinalli))|publisher=McGraw-Hill Companies |location=New York |year=2010 |pages=830–839 |isbn=978-0-07-148480-0 }}</ref> Repeat infections are typically seen in areas with poor sanitation, and [[malnutrition]].<ref name=Web09/> [[Stunted growth]] and long-term cognitive delays can result.<ref name=M93/>

[[Reactive arthritis]] occurs in 1% of people following infections with ''Campylobacter'' species.<ref name=Bact2007/> [[Guillain–Barré syndrome]] occurs in 0.1%.<ref name=Bact2007/> [[Hemolytic uremic syndrome]] (HUS) may occur due to infection with [[Shiga toxin]]-producing ''Escherichia coli'' or ''Shigella'' species.<ref name=BMJ2007/> HUS causes [[thrombocytopenia|low platelet counts]], [[renal failure|poor kidney function]], and [[hemolytic anemia|low red blood cell count (due to their breakdown)]].<ref name="BMJ2007">{{cite journal|last=Elliott|first=EJ|title=Acute gastroenteritis in children.|journal=The BMJ|date=6 January 2007 |volume=334|issue=7583|pages=35–40|pmid=17204802|doi=10.1136/bmj.39036.406169.80|pmc=1764079}}</ref> Children are more predisposed to getting HUS than adults.<ref name=M93/> Some viral infections may produce [[Benign infantile epilepsy|benign infantile seizures]].<ref name=EBMED2010/>

==Cause==
[[Viruses]] (particularly [[rotavirus]] (in children) and [[norovirus]] (in adults)) and the bacteria ''[[Escherichia coli]]'' and ''[[Campylobacter]]'' species are the primary causes of gastroenteritis.<ref name=Web09/><ref name=Sz2010/> There are, however, many other infectious agents that can cause this syndrome including [[parasites]] and [[fungus|fungi]].<ref name=M93/><ref name=Helm2006/> Non-infectious causes are seen on occasion, but they are less likely than a viral or bacterial cause.<ref name=EBMED2010/> Risk of infection is higher in children due to their lack of [[immunity (medical)|immunity]].<ref name=EBMED2010/> Children are also at higher risk because they are less likely to practice good [[hygiene]] habits.<ref name=EBMED2010/> Children living in areas without easy [[WASH|access to water and soap]] are especially vulnerable.<ref name=EBMED2010/>

===Viral===
[[Rotavirus]]es, [[norovirus]]es, [[adenovirus]]es, and [[astrovirus]]es are known to cause viral gastroenteritis.<ref name=Kumar2020>{{cite book |last1=Barlow |first1=Gavin |last2=Irving |first2=William L. |last3=Moss |first3=Peter J. |editor1-last=Feather |editor1-first=Adam |editor2-last=Randall |editor2-first=David |editor3-last=Waterhouse |editor3-first=Mona |title=Kumar and Clark's Clinical Medicine |date=2020 |publisher=Elsevier |isbn=978-0-7020-7870-5 |pages=529–530 |edition=10th |chapter-url=https://books.google.com/books?id=sl3sDwAAQBAJ&pg=PA529 |language=en |chapter=20. Infectious disease }}</ref> Rotavirus is the most common cause of gastroenteritis in children,<ref name=Sz2010/> and produces similar rates in both the [[developed world|developed]] and [[developing world]].<ref name=Rota2011/> Viruses cause about 70% of episodes of infectious diarrhea in the pediatric age group.<ref name=Webb2005/> Rotavirus is a less common cause in adults due to acquired immunity.<ref name="ID2011">{{cite journal |vauthors=Desselberger U, Huppertz HI |title=Immune responses to rotavirus infection and vaccination and associated correlates of protection |journal=The Journal of Infectious Diseases |volume=203 |issue=2 |pages=188–95 |date=January 2011 |pmid=21288818 |pmc=3071058 |doi=10.1093/infdis/jiq031 }}</ref> Norovirus is the cause in about 18% of all cases.<ref>{{cite journal|last1=Ahmed|first1=Sharia M|last2=Hall|first2=Aron J|last3=Robinson|first3=Anne E|last4=Verhoef|first4=Linda|last5=Premkumar|first5=Prasanna|last6=Parashar|first6=Umesh D|last7=Koopmans|first7=Marion|last8=Lopman|first8=Benjamin A|title=Global prevalence of norovirus in cases of gastroenteritis: a systematic review and meta-analysis|journal=The Lancet Infectious Diseases|doi=10.1016/S1473-3099(14)70767-4|pmid=24981041|volume=14|issue=8|date=Aug 2014|pages=725–30|pmc=8006533|url=https://zenodo.org/record/1260252}}</ref> Generally speaking, viral gastroenteritis accounts for 21–40% of the cases of infectious diarrhea in developed countries.<ref>{{Cite journal|last=Baumgart|first=Alexander J. Eckardt and Daniel C.|date=2010-12-31|title=Viral Gastroenteritis in Adults|url=https://www.eurekaselect.com/76857/article|access-date=2020-12-22|journal=Recent Patents on Anti-Infective Drug Discovery|volume=6|issue=1|pages=54–63|doi=10.2174/157489111794407877|pmid=21210762|language=en|url-access=subscription}}</ref>

Norovirus is the leading cause of gastroenteritis among adults in America accounting for about 90% of viral gastroenteritis outbreaks.<ref name=Eck2011/> These localized [[epidemic]]s typically occur when groups of people spend time proximate to each other, such as on [[cruise ships]],<ref name=Eck2011/> in hospitals, or in restaurants.<ref name=EBMED2010/> People may remain infectious even after their diarrhea has ended.<ref name=Eck2011/> Norovirus is the cause of about 10% of cases in children.<ref name=EBMED2010/>

===Bacterial===
[[File:Salmonella Typhimurium Gram.jpg|thumb|''Salmonella enterica'' serovar Typhimurium (ATCC 14028) as seen with a microscope at 1000 fold magnification and following Gram staining]]
In some countries, ''[[Campylobacter jejuni]]'' is the primary cause of bacterial gastroenteritis, with half of these cases associated with exposure to [[poultry]].<ref name="Bact2007">{{cite journal|last=Galanis|first=E|title=Campylobacter and bacterial gastroenteritis.|journal=Canadian Medical Association Journal |date=11 September 2007 |volume=177|issue=6|pages=570–1|pmid=17846438|doi=10.1503/cmaj.070660|pmc=1963361}}</ref> In children, bacteria are the cause in about 15% of cases, with the most common types being ''[[Escherichia coli]]'', ''[[Salmonella]]'', ''[[Shigella]]'', and ''Campylobacter'' species.<ref name=Webb2005/> If food becomes contaminated with bacteria and remains at room temperature for several hours, the bacteria multiply and increase the risk of infection in those who consume the food.<ref name=M93/> Some foods commonly associated with illness include raw or undercooked meat, poultry, seafood, and eggs; raw sprouts; unpasteurized milk and soft cheeses; and fruit and vegetable juices.<ref>{{cite journal|last=Nyachuba|first=DG|title=Foodborne illness: is it on the rise?|journal=Nutrition Reviews|date=May 2010 |volume=68|issue=5|pages=257–69|pmid=20500787|doi=10.1111/j.1753-4887.2010.00286.x}}</ref> In the developing world, especially sub-Saharan Africa and Asia, [[cholera]] is a common cause of gastroenteritis.<!-- <ref name=Cholera11/> --> This infection is usually transmitted by contaminated water or food.<ref name="Cholera11">{{cite journal|last=Charles|first=RC|author2=Ryan, ET|title=Cholera in the 21st century.|journal=Current Opinion in Infectious Diseases|date=October 2011 |volume=24|issue=5|pages=472–7|pmid=21799407|doi=10.1097/QCO.0b013e32834a88af|s2cid=6907842}}</ref>

Toxigenic ''[[Clostridioides difficile infection|Clostridioides difficile]]'' is an important cause of diarrhea that occurs more often in the elderly.<ref name=M93/> Infants can carry these bacteria without developing symptoms.<ref name=M93/> It is a common cause of diarrhea in those who are hospitalized and is frequently associated with antibiotic use.<ref>{{cite journal|last=Moudgal|first=V|author2=Sobel, JD|title=''Clostridium difficile'' colitis: a review.|journal=Hospital Practice |date=February 2012 |volume=40|issue=1|pages=139–48|pmid=22406889|doi=10.3810/hp.2012.02.954|s2cid=23015631}}</ref> ''[[Staphylococcus aureus]]'' infectious diarrhea may also occur in those who have used antibiotics.<ref>{{cite journal|last=Lin|first=Z|author2=Kotler, DP |author3=Schlievert, PM |author4= Sordillo, EM |title=Staphylococcal enterocolitis: forgotten but not gone?|journal=Digestive Diseases and Sciences|date=May 2010 |volume=55|issue=5|pages=1200–7|pmid=19609675|doi=10.1007/s10620-009-0886-1|s2cid=2023416}}</ref> Acute "[[traveler's diarrhea]]" is usually a type of bacterial gastroenteritis, while the persistent form is usually parasitic.<ref name="CDC Travelers'">{{cite web|title=Persistent Travelers' Diarrhea|url=http://wwwnc.cdc.gov/travel/yellowbook/2016/post-travel-evaluation/persistent-travelers-diarrhea|publisher=United States Centers for Disease Control and Prevention|access-date=9 January 2016|date=10 July 2015|quote=Although most cases of travelers' diarrhea are acute and self-limited, a certain percentage of travelers will develop persistent (>14 days) gastrointestinal symptoms&nbsp;... Parasites as a group are the pathogens most likely to be isolated from patients with persistent diarrhea|url-status=live|archive-url=https://web.archive.org/web/20160103203635/http://wwwnc.cdc.gov/travel/yellowbook/2016/post-travel-evaluation/persistent-travelers-diarrhea|archive-date=3 January 2016}}</ref> Acid-suppressing medication appears to increase the risk of significant infection after exposure to several organisms, including ''Clostridioides difficile'', ''Salmonella'', and ''Campylobacter'' species.<ref name="PPI2007">{{cite journal|last=Leonard|first=J |author2=Marshall, JK |author3=Moayyedi, P|title=Systematic review of the risk of enteric infection in patients taking acid suppression.|journal=The American Journal of Gastroenterology|date=September 2007 |volume=102|issue=9|pages=2047–56; quiz 2057|doi=10.1111/j.1572-0241.2007.01275.x |pmid=17509031|s2cid=12326803 }}</ref> The risk is greater in those taking [[proton pump inhibitors]] than with [[H2 antagonist|H<sub>2</sub> antagonist]]s.<ref name=PPI2007/>

===Parasitic===
A number of [[parasites]] can cause gastroenteritis.<ref name=Webb2005/> ''[[Giardia lamblia]]'' is most common, but ''[[Entamoeba histolytica]]'', ''[[Cryptosporidium]]'' spp., and other species have also been implicated.<ref name=Webb2005/><ref name="CDC Travelers'" /> As a group, these agents comprise about 10% of cases in children.<ref name=BMJ2007 /><ref name="CDC Travelers'" /> ''Giardia'' occurs more commonly in the developing world, but this type of illness can occur nearly everywhere.<ref name="Giar2010">{{cite journal|last=Escobedo|first=AA|author2=Almirall, P |author3=Robertson, LJ |author4=Franco, RM |author5=Hanevik, K |author6=Mørch, K |author7=Cimerman, S |title=Giardiasis: the ever-present threat of a neglected disease|journal=Infectious Disorders Drug Targets|date=October 2010 |volume=10|issue=5|pages=329–48|pmid=20701575|doi=10.2174/187152610793180821}}</ref> It occurs more commonly in persons who have traveled to areas with high prevalence, children who attend [[day care]], [[men who have sex with men]], and following [[disasters]].<ref name=Giar2010/>

===Transmission===
Transmission may occur from drinking contaminated water or when people share personal objects.<ref name=Web09/> Water quality typically worsens during the rainy season and outbreaks are more common at this time.<ref name=Web09/> In [[Temperateness|areas with four seasons]], infections are more common in the winter.<ref name=M93/> Worldwide, [[bottle-feeding]] of babies with improperly sanitized bottles is a significant cause.<ref name=Web09/> Transmission rates are also related to poor hygiene, (especially among children),<ref name=Eck2011/> in crowded households,<ref>{{cite journal|last=Grimwood|first=K|author2=Forbes, DA|title=Acute and persistent diarrhea|journal=Pediatric Clinics of North America|date=December 2009 |volume=56|issue=6|pages=1343–61|pmid=19962025|doi=10.1016/j.pcl.2009.09.004}}</ref> and in those with poor nutritional status.<ref name=M93/> Adults who have developed immunities might still carry certain organisms without exhibiting symptoms.<ref name=M93/> Thus, adults can become [[natural reservoirs]] of certain diseases.<ref name=M93/> While some agents (such as ''Shigella'') only occur in [[primates]], others (such as ''Giardia'') may occur in a wide variety of animals.<ref name=M93/>

===Non-infectious===
There are a number of non-infectious causes of inflammation of the gastrointestinal tract.<ref name=EBMED2010/> Some of the more common include medications (like [[NSAIDs]]), certain foods such as [[lactose]] (in those who are intolerant), and [[gluten]] (in those with [[Coeliac disease|celiac disease]]). [[Crohn's disease]] is also a non-infectious cause of (often severe) gastroenteritis.<ref name=EBMED2010/> Disease secondary to [[toxin]]s may also occur. Some food-related conditions associated with nausea, vomiting, and diarrhea include: [[Ciguatera|ciguatera poisoning]] due to consumption of contaminated predatory fish, [[scombroid food poisoning|scombroid]] associated with the consumption of certain types of spoiled fish, [[Tetrodotoxin#Poisoning|tetrodotoxin poisoning]] from the consumption of [[puffer fish]] among others, and [[botulism]] typically due to improperly preserved food.<ref>{{cite journal|last=Lawrence|first=DT|author2=Dobmeier, SG |author3=Bechtel, LK |author4= Holstege, CP |title=Food poisoning|journal=Emergency Medicine Clinics of North America|date=May 2007 |volume=25|issue=2|pages=357–73; abstract ix|pmid=17482025|doi=10.1016/j.emc.2007.02.014}}</ref>

In the United States, rates of emergency department use for noninfectious gastroenteritis dropped 30% from 2006 until 2011. Of the twenty most common conditions seen in the emergency department, rates of noninfectious gastroenteritis had the largest decrease in visits in that time period.<ref>{{cite journal | vauthors = Skiner HG, Blanchard J, Elixhauser A | title = Trends in Emergency Department Visits, 2006–2011 | journal =HCUP Statistical Brief |issue=179 | publisher = Agency for Healthcare Research and Quality | location = Rockville, MD | date = September 2014 | url = https://www.hcup-us.ahrq.gov/reports/statbriefs/sb179-Emergency-Department-Trends.jsp | url-status=live | archive-url = https://web.archive.org/web/20141224224220/http://www.hcup-us.ahrq.gov/reports/statbriefs/sb179-Emergency-Department-Trends.jsp | archive-date = 2014-12-24 }}</ref>

==Pathophysiology==

Gastroenteritis is defined as [[vomiting]] or [[diarrhea]] due to inflammation of the [[small bowel|small]] or [[large bowel]], often due to infection.<ref name=M93/> The changes in the small bowel are typically noninflammatory, while the ones in the large bowel are inflammatory.<ref name=M93/> The number of pathogens required to cause an infection varies from as few as one (for ''Cryptosporidium'') to as many as 10<sup>8</sup> (for ''Vibrio cholerae'').<ref name=M93/>

==Diagnosis==
Gastroenteritis is typically diagnosed clinically, based on a person's signs and symptoms.<ref name=Eck2011/> Determining the exact cause is usually not needed as it does not alter the management of the condition.<ref name=Web09/>

However, [[stool culture]]s should be performed in those with blood in the stool, those who might have been exposed to [[food poisoning]], and those who have recently traveled to the developing world.<ref name=Webb2005/> It may also be appropriate in children younger than 5, old people, and those with poor immune function.<ref name="IDSA2017">{{cite journal|last1=Shane|first1=Andi L|last2=Mody|first2=Rajal K|last3=Crump|first3=John A|last4=Tarr|first4=Phillip I|last5=Steiner|first5=Theodore S|last6=Kotloff|first6=Karen|last7=Langley|first7=Joanne M|last8=Wanke|first8=Christine|last9=Warren|first9=Cirle Alcantara|last10=Cheng|first10=Allen C|last11=Cantey|first11=Joseph|last12=Pickering|first12=Larry K|title=2017 Infectious Diseases Society of America Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea|journal=Clinical Infectious Diseases|date=19 October 2017|doi=10.1093/cid/cix669|pmid=29053792|pmc=5850553|volume=65|issue=12|pages=e45–e80}}</ref> Diagnostic testing may also be done for surveillance.<ref name=Eck2011/> As [[hypoglycemia]] occurs in approximately 10% of infants and young children, measuring serum [[glucose]] in this population is recommended.<ref name=Tint10/> [[Electrolytes]] and [[creatinine|kidney function]] should also be checked when there is a concern about severe dehydration.<ref name=Webb2005/>

===Dehydration===
A determination of whether or not the person has [[dehydration]] is an important part of the assessment, with dehydration typically divided into mild (3–5%), moderate (6–9%), and severe (≥10%) cases.<ref name=EBMED2010/> In children, the most accurate signs of moderate or severe dehydration are a prolonged [[capillary refill]], poor [[skin turgor]], and abnormal breathing.<ref name=Tint10/><ref>{{cite journal|last=Steiner|first=MJ |author2=DeWalt, DA |author3-link=Julie Story Byerley |author3=Byerley JS|title=Is this child dehydrated?|journal=JAMA: The Journal of the American Medical Association|date=9 June 2004 |volume=291|issue=22|pages=2746–54|pmid=15187057|doi=10.1001/jama.291.22.2746}}</ref> Other useful findings (when used in combination) include sunken eyes, decreased activity, a lack of tears, and a dry mouth.<ref name=EBMED2010/> A normal urinary output and oral fluid intake is reassuring.<ref name=Tint10/> Laboratory testing is of little clinical benefit in determining the degree of dehydration.<ref name=EBMED2010/> Thus the use of urine testing or ultrasounds is generally not needed.<ref>{{cite journal|last1=Freedman|first1=SB|last2=Vandermeer|first2=B|last3=Milne|first3=A|last4=Hartling|first4=L|title=Diagnosing clinically significant dehydration in children with acute gastroenteritis using noninvasive methods: a meta-analysis|journal=The Journal of Pediatrics|date=April 2015|volume=166|issue=4|pages=908–916.e6|pmid=25641247|doi=10.1016/j.jpeds.2014.12.029|s2cid=29662891 }}</ref>

===Differential diagnosis===
Other potential causes of signs and symptoms that mimic those seen in gastroenteritis that need to be ruled out include [[appendicitis]], [[volvulus]], [[inflammatory bowel disease]], [[urinary tract infection]]s, and [[diabetes mellitus]].<ref name=Webb2005/> [[Pancreatic insufficiency]], [[short bowel syndrome]], [[Whipple's disease]], [[coeliac disease]], and [[laxative]] abuse should also be considered.<ref name="Oxford">{{cite book|editor1=Warrell D.A. |editor2=Cox T.M. |editor3=Firth J.D. |editor4=Benz E.J. |title=The Oxford Textbook of Medicine |publisher=Oxford University Press |year=2003 |isbn=978-0-19-262922-7 |edition=4th |url=http://otm.oxfordmedicine.com/ |url-status=dead |archive-url=https://web.archive.org/web/20120321002102/http://otm.oxfordmedicine.com/ |archive-date=2012-03-21 }}</ref> The differential diagnosis can be complicated somewhat if the person exhibits ''only'' vomiting or diarrhea (rather than both).<ref name=EBMED2010/>

Appendicitis may present with vomiting, abdominal pain, and a small amount of diarrhea in up to 33% of cases.<ref name=EBMED2010/> This is in contrast to the large amount of diarrhea that is typical of gastroenteritis.<ref name=EBMED2010/> [[Lower respiratory tract infection|Infections of the lungs]] or urinary tract in children may also cause vomiting or diarrhea.<ref name=EBMED2010/> Classical [[diabetic ketoacidosis]] (DKA) presents with abdominal pain, nausea, and vomiting, but without diarrhea.<ref name=EBMED2010/> One study found that 17% of children with DKA were initially diagnosed as having gastroenteritis.<ref name=EBMED2010/>

==Prevention==
[[File:RotavirusV2009.gif|thumb|upright=1.3|Percentage of rotavirus tests with positive results, by surveillance week, United States, July 2000 – June 2009]]

===Water, sanitation, hygiene===
{{Further|WASH#Health aspects}}
A supply of easily accessible uncontaminated water and good [[sanitation]] practices are important for reducing rates of infection and clinically significant gastroenteritis.<ref name=M93/> Personal [[hygiene]] measures (such as [[hand washing]] with soap) have been found to decrease rates of gastroenteritis in both the developing and developed world by as much as 30%.<ref name=Tint10/> Alcohol-based gels may also be effective.<ref name=Tint10/> Food or drink that is thought to be contaminated should be avoided.<ref>{{cite web|title=Viral Gastroenteritis |url=https://www.cdc.gov/ncidod/dvrd/revb/gastro/faq.htm |work=Center for Disease Control and Prevention |access-date=16 April 2012 |date=February 2011 |url-status=dead |archive-url=https://web.archive.org/web/20120424073547/http://www.cdc.gov/ncidod/dvrd/revb/gastro/faq.htm |archive-date=24 April 2012 }}</ref>
[[Breastfeeding]] is important, especially in places with poor hygiene, as is improvement of hygiene generally.<ref name=Web09/> Breast milk reduces both the frequency of infections and their duration.<ref name=EBMED2010/>

===Vaccination===
Due to both its effectiveness and safety, in 2009 the World Health Organization recommended that the [[rotavirus vaccine]] be offered to all children globally.<ref name="Sz2010">{{cite journal|last=Szajewska|first=H|author2=Dziechciarz, P|title=Gastrointestinal infections in the pediatric population|journal=Current Opinion in Gastroenterology|date=January 2010 |volume=26|issue=1|pages=36–44|pmid=19887936|doi=10.1097/MOG.0b013e328333d799|s2cid=5083478}}</ref><ref name="WHORota2009">{{cite journal|last=World Health Organization|title=Rotavirus vaccines: an update|journal=Weekly Epidemiological Record|date=December 2009|volume=84|issue=50|pages=533–540|pmid=20034143|url=https://www.who.int/wer/2009/wer8451_52.pdf|access-date=10 May 2012|url-status=live|archive-url=https://web.archive.org/web/20120709034841/http://www.who.int/wer/2009/wer8451_52.pdf|archive-date=9 July 2012}}</ref> Two commercial rotavirus vaccines exist and several more are in development.<ref name=WHORota2009/> In Africa and Asia these vaccines reduced severe disease among infants<ref name=WHORota2009/> and countries that have put in place national immunization programs have seen a decline in the rates and severity of disease.<ref>{{cite journal|vauthors=Giaquinto C, Dominiak-Felden G, Van Damme P, Myint TT, Maldonado YA, Spoulou V, Mast TC, Staat MA|title=Summary of effectiveness and impact of rotavirus vaccination with the oral pentavalent rotavirus vaccine: a systematic review of the experience in industrialized countries|journal=Human Vaccines|date=July 2011|volume=7|pages=734–748|url=http://www.landesbioscience.com/journals/vaccines/article/15511/?nocache=1111012137|access-date=10 May 2012|doi=10.4161/hv.7.7.15511|pmid=21734466|issue=7|s2cid=23996836|url-status=live|archive-url=https://web.archive.org/web/20130217163038/http://www.landesbioscience.com/journals/vaccines/article/15511/?nocache=1111012137|archive-date=17 February 2013|doi-access=free}}</ref><ref>{{cite journal|last=Jiang|first=V|author2=Jiang B|author3=Tate J|author4=Parashar UD|author5=Patel MM|title=Performance of rotavirus vaccines in developed and developing countries|journal=Human Vaccines|date=July 2010|volume=6|issue=7|pages=532–542|url=http://www.landesbioscience.com/journals/vaccines/article/11278/?nocache=531156378|access-date=10 May 2012|pmid=20622508|pmc=3322519|doi=10.4161/hv.6.7.11278|url-status=dead|archive-url=https://web.archive.org/web/20130217163031/http://www.landesbioscience.com/journals/vaccines/article/11278/?nocache=531156378|archive-date=17 February 2013}}</ref> This vaccine may also prevent illness in non-vaccinated children by reducing the number of circulating infections.<ref>{{cite journal|last=Patel|first=MM|author2=Steele, D |author3=Gentsch, JR |author4=Wecker, J |author5=Glass, RI |author6=Parashar, UD |title=Real-world impact of rotavirus vaccination|journal=The Pediatric Infectious Disease Journal|date=January 2011 |volume=30|issue=1 Suppl|pages=S1–5|pmid=21183833|doi=10.1097/INF.0b013e3181fefa1f|s2cid=1893099 |doi-access=free}}</ref> Since 2000, the implementation of a rotavirus vaccination program in the United States has substantially decreased the number of cases of diarrhea by as much as 80 percent.<ref name="CDC Rota">{{cite journal|last=US Center for Disease Control and Prevention|title=Delayed onset and diminished magnitude of rotavirus activity—United States, November 2007 – May 2008|journal=Morbidity and Mortality Weekly Report|year=2008|volume=57|issue=25|pages=697–700|url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5725a6.htm|access-date=3 May 2012|pmid=18583958|url-status=live|archive-url=https://web.archive.org/web/20120608073201/http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5725a6.htm|archive-date=8 June 2012}}</ref><ref>{{cite journal |title=Reduction in rotavirus after vaccine introduction—United States, 2000–2009 |journal=Morbidity and Mortality Weekly Report |volume=58 |issue=41 |pages=1146–9 |date=October 2009 |pmid=19847149 |url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5841a2.htm |url-status=live |archive-url=https://web.archive.org/web/20091031060444/http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5841a2.htm |archive-date=2009-10-31 |author1=Centers for Disease Control Prevention (CDC) }}</ref><ref>{{cite journal|last=Tate|first=JE |author2=Cortese, MM |author3=Payne, DC |author4=Curns, AT |author5=Yen, C |author6=Esposito, DH |author7=Cortes, JE |author8=Lopman, BA |author9=Patel, MM |author10=Gentsch, JR |author11=Parashar, UD|title=Uptake, impact, and effectiveness of rotavirus vaccination in the United States: review of the first 3 years of postlicensure data|journal=The Pediatric Infectious Disease Journal|date=January 2011 |volume=30|issue=1 Suppl|pages=S56–60|pmid=21183842|doi=10.1097/INF.0b013e3181fefdc0|s2cid=20940659 |doi-access=free }}</ref> The first dose of vaccine should be given to infants between 6 and 15 weeks of age.<ref name=Sz2010/> The [[Cholera vaccine|oral cholera vaccine]] has been found to be 50–60% effective over two years.<ref>{{cite journal|editor1-last=Sinclair|editor1-first=David|last=Sinclair|first=D|author2=Abba, K |author3=Zaman, K |author4=Qadri, F |author5=Graves, PM |title=Oral vaccines for preventing cholera.|journal=Cochrane Database of Systematic Reviews |date=16 March 2011 |volume=2011 |issue=3|pages=CD008603|pmid=21412922|doi=10.1002/14651858.CD008603.pub2|pmc=6532691}}</ref>

There are a number of vaccines against gastroenteritis in development. For example, vaccines against ''Shigella'' and enterotoxigenic ''Escherichia coli'' (ETEC), which are two of the leading bacterial causes of gastroenteritis worldwide.<ref name="WHO ETEC">{{cite web|author=World Health Organization|title=Enterotoxigenic Escherichia coli (ETEC)|url=https://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html|url-status=dead|archive-url=https://web.archive.org/web/20120515142857/http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html|archive-date=15 May 2012|access-date=3 May 2012|work=Diarrhoeal Diseases}}</ref><ref name="WHO Shig">{{cite web|author=World Health Organization|title=Shigellosis|url=https://www.who.int/vaccine_research/diseases/diarrhoeal/en/index6.html|url-status=dead|archive-url=https://web.archive.org/web/20081215123745/http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index6.html|archive-date=15 December 2008|access-date=3 May 2012|work=Diarrhoeal Diseases}}</ref>

==Management==
Gastroenteritis is usually an acute and self-limiting disease that does not require medication.<ref name=NICE2009/> The preferred treatment in those with mild to moderate [[dehydration]] is [[oral rehydration therapy]] (ORT).<ref name=BMJ2007 /> For children at risk of dehydration from vomiting, taking a single dose of the [[antiemetic|anti vomiting]] medication [[metoclopramide]] or [[ondansetron]], may be helpful,<ref name="Fedorowicz2011">{{Cite journal|last1=Fedorowicz|first1=Zbys|last2=Jagannath|first2=Vanitha A.|last3=Carter|first3=Ben|date=2011-09-07|title=Antiemetics for reducing vomiting related to acute gastroenteritis in children and adolescents|journal=Cochrane Database of Systematic Reviews|volume=130|issue=9|pages=270|doi=10.1002/14651858.CD005506.pub5|issn=1469-493X|pmid=21901699|pmc=6768985}}</ref> and [[butylscopolamine]] is useful in treating [[abdominal pain]].<ref>{{cite journal |author=Tytgat GN |title=Hyoscine butylbromide: a review of its use in the treatment of abdominal cramping and pain |journal=Drugs |volume=67 |issue=9 |pages=1343–57 |year=2007 |pmid=17547475 |doi=10.2165/00003495-200767090-00007|s2cid=46971321 }}</ref>

===Rehydration===
The primary treatment of gastroenteritis in both children and adults is [[Fluid replacement|rehydration]]. This is preferably achieved by drinking rehydration solution, although [[intravenous therapy|intravenous]] delivery may be required if there is a [[decreased level of consciousness]] or if dehydration is severe.<ref>{{cite web |url=http://www.bestbets.org/bets/bet.php?id=1039 |title=BestBets: Fluid Treatment of Gastroenteritis in Adults |url-status=live |archive-url=https://web.archive.org/web/20090212164231/http://www.bestbets.org/bets/bet.php?id=1039 |archive-date=2009-02-12 }}</ref><ref>{{cite journal |vauthors=Canavan A, Arant BS |title=Diagnosis and management of dehydration in children |journal=American Family Physician |volume=80 |issue=7 |pages=692–6 |date=October 2009 |pmid=19817339 }}</ref> Drinking replacement therapy products made with complex carbohydrates (i.e. those made from wheat or rice) may be superior to those based on simple sugars.<ref>{{cite journal|last1=Gregorio|first1=GV|last2=Gonzales|first2=ML|last3=Dans|first3=LF|last4=Martinez|first4=EG|title=Polymer-based oral rehydration solution for treating acute watery diarrhoea|journal=Cochrane Database of Systematic Reviews|date=13 December 2016|volume=2016|issue=12 |pages=CD006519|pmid=27959472|doi=10.1002/14651858.CD006519.pub3|pmc=5450881}}</ref> Drinks especially high in simple sugars, such as [[soft drinks]] and fruit juices, are not recommended in children under five years of age as they may ''increase'' diarrhea.<ref name=NICE2009/> Plain water may be used if more specific ORT preparations are unavailable or the person is not willing to drink them.<ref name=NICE2009/> A [[nasogastric tube]] can be used in young children to administer fluids if warranted.<ref name=Webb2005/> In those who require intravenous fluids, one to four hours' worth is often sufficient.<ref>{{cite journal |last1=Toaimah|first1=FH|last2=Mohammad|first2=HM|s2cid=20509810|title=Rapid Intravenous Rehydration Therapy in Children With Acute Gastroenteritis: A Systematic Review|journal=Pediatric Emergency Care |date=February 2016|volume=32|issue=2|pages=131–5|pmid=26835574|doi=10.1097/pec.0000000000000708}}</ref>

===Dietary===
It is recommended that breast-fed infants continue to be nursed in the usual fashion,  and that formula-fed infants continue their formula immediately after rehydration with ORT.<ref name="MMWR2003">{{cite journal |vauthors=King CK, Glass R, Bresee JS, Duggan C |title=Managing acute gastroenteritis among children: oral rehydration, maintenance, and nutritional therapy |journal= MMWR. Recommendations and Reports |volume=52 |issue=RR-16 |pages=1–16 |date=November 2003 |pmid=14627948 |url=https://www.cdc.gov/mmwr/preview/mmwrhtml/rr5216a1.htm |url-status=live |archive-url=https://web.archive.org/web/20141028174056/http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5216a1.htm |archive-date=2014-10-28 }}</ref> Lactose-free or lactose-reduced formulas usually are not necessary.<ref name=MMWR2003/> Children should continue their usual diet during episodes of diarrhea with the exception that foods high in [[simple sugar]]s should be avoided.<ref name=MMWR2003/> The [[BRAT diet]] (bananas, rice, applesauce, toast and tea) is no longer recommended, as it contains insufficient nutrients and has no benefit over normal feeding.<ref name=MMWR2003/>

A Cochrane Review from 2020 concludes that [[probiotic]]s make little or no difference to people who have diarrhea lasting 2 days or longer and that there is no proof that they reduce its duration.<ref>{{cite journal | vauthors = Collinson S, Deans A, Padua-Zamora A, Gregorio GV, Li C, Dans LF, Allen SJ | title = Probiotics for treating acute infectious diarrhoea | journal = Cochrane Database Syst Rev | volume = 2020 | issue = 12 | pages = CD003048 | date = December 2020 | pmid = 33295643 | pmc = 8166250 | doi = 10.1002/14651858.CD003048.pub4 }}</ref> They may be useful in preventing and treating [[antibiotic associated diarrhea]].<ref>{{cite journal|last=Hempel|first=S|author2=Newberry, SJ |author3=Maher, AR |author4=Wang, Z |author5=Miles, JN |author6=Shanman, R |author7=Johnsen, B |author8= Shekelle, PG |title=Probiotics for the prevention and treatment of antibiotic-associated diarrhea: a systematic review and meta-analysis|journal=JAMA: The Journal of the American Medical Association|date=9 May 2012 |volume=307|issue=18|pages=1959–69|pmid=22570464|doi=10.1001/jama.2012.3507|doi-access=}}</ref> Fermented milk products (such as [[yogurt]]) are similarly beneficial.<ref>{{cite web|last=Mackway-Jones|first=Kevin|title=Does yogurt decrease acute diarrhoeal symptoms in children with acute gastroenteritis?|url=http://www.bestbets.org/bets/bet.php?id=1000|work=BestBets|date=June 2007|url-status=live|archive-url=https://web.archive.org/web/20090212163443/http://www.bestbets.org/bets/bet.php?id=1000|archive-date=2009-02-12}}</ref> [[Zinc]] supplementation appears to be effective in both treating and preventing diarrhea among children in the developing world.<ref>{{cite journal|last=Telmesani|first=AM|title=Oral rehydration salts, zinc supplement and rota virus vaccine in the management of childhood acute diarrhea.|journal=Journal of Family and Community Medicine|date=May 2010 |volume=17|issue=2|pages=79–82|pmid=21359029|doi=10.4103/1319-1683.71988|pmc=3045093 |doi-access=free }}</ref>

===Antiemetics===
[[Antiemetic]] medications may be helpful for treating vomiting in children. [[Ondansetron]] has some utility, with a single dose being associated with less need for intravenous fluids, fewer hospitalizations, and decreased vomiting.<ref name=Fedorowicz2011 /><ref>{{cite journal |vauthors=DeCamp LR, Byerley JS, Doshi N, Steiner MJ |title=Use of antiemetic agents in acute gastroenteritis: a systematic review and meta-analysis |journal=Archives of Pediatrics & Adolescent Medicine |volume=162 |issue=9 |pages=858–65 |date=September 2008 |pmid=18762604|doi=10.1001/archpedi.162.9.858 |doi-access=free }}</ref><ref name="pmid17279195">{{cite journal|vauthors=Mehta S, Goldman RD | title = Ondansetron for acute gastroenteritis in children| journal = Canadian Family Physician| volume = 52| issue = 11| pages = 1397–8| year = 2006| pmid = 17279195 | url =http://www.cfp.ca/cgi/pmidlookup?view=long&pmid=17279195 | pmc = 1783696 }}</ref><ref name=Cochrane2011/> [[Metoclopramide]] might also be helpful.<ref name="Cochrane2011">{{cite journal|editor1-last=Fedorowicz|editor1-first=Zbys|last=Fedorowicz|first=Z |author2=Jagannath, VA |author3=Carter, B|title=Antiemetics for reducing vomiting related to acute gastroenteritis in children and adolescents|journal=Cochrane Database of Systematic Reviews |date=7 September 2011 |volume=9|issue=9|pages=CD005506|pmid=21901699|pmc=6768985|doi=10.1002/14651858.CD005506.pub5}}</ref> However, the use of ondansetron might possibly be linked to an increased rate of return to hospital in children.<ref>{{cite journal |vauthors=Sturm JJ, Hirsh DA, Schweickert A, Massey R, Simon HK |title=Ondansetron use in the pediatric emergency department and effects on hospitalization and return rates: are we masking alternative diagnoses? |journal=Annals of Emergency Medicine |volume=55 |issue=5 |pages=415–22 |date=May 2010 |pmid=20031265 |doi=10.1016/j.annemergmed.2009.11.011 }}</ref> The intravenous preparation of ondansetron may be given orally if clinical judgment warrants.<ref>{{cite web|title=Ondansetron|url=http://www.merckmanuals.com/professional/print/lexicomp/ondansetron.html|work=Lexi-Comp|date=May 2011|url-status=live|archive-url=https://web.archive.org/web/20120606132320/http://www.merckmanuals.com/professional/print/lexicomp/ondansetron.html|archive-date=2012-06-06}}</ref> [[Dimenhydrinate]], while reducing vomiting, does not appear to have a significant clinical benefit.<ref name=EBMED2010/>

===Antibiotics===
Antibiotics are not usually used for gastroenteritis, although they are sometimes recommended if symptoms are particularly severe<ref>{{cite journal |vauthors=Traa BS, Walker CL, Munos M, Black RE |title=Antibiotics for the treatment of dysentery in children |journal=International Journal of Epidemiology |volume=39 |issue=Suppl 1 |pages=i70–4 |date=April 2010 |pmid=20348130 |pmc=2845863 |doi=10.1093/ije/dyq024 }}</ref> or if a susceptible bacterial cause is isolated or suspected.<ref>{{cite journal |vauthors=Grimwood K, Forbes DA |title=Acute and persistent diarrhea |journal=Pediatric Clinics of North America |volume=56 |issue=6 |pages=1343–61 |date=December 2009 |pmid=19962025 |doi=10.1016/j.pcl.2009.09.004 }}</ref> If antibiotics are to be employed, a [[macrolide]] (such as [[azithromycin]]) is preferred over a [[fluoroquinolone]] due to higher rates of resistance to the latter.<ref name=Bact2007/> [[Pseudomembranous colitis]], usually caused by antibiotic use, is managed by discontinuing the causative agent and treating it with either [[metronidazole]] or [[vancomycin]].<ref name="Mandell"/> Bacteria and protozoans that are amenable to treatment include ''[[shigellosis|Shigella]]''<ref>{{cite journal|editor1-last=Christopher|editor1-first=Prince RH|last=Christopher|first=PR |author2=David, KV |author3=John, SM |author4=Sankarapandian, V|title=Antibiotic therapy for Shigella dysentery.|journal=Cochrane Database of Systematic Reviews |date=4 August 2010 |volume=2010 |issue=8|pages=CD006784|pmid=20687081|doi=10.1002/14651858.CD006784.pub4|pmc=6532574}}</ref> ''[[Salmonellosis|Salmonella typhi]]'',<ref>{{cite journal|editor1-last=Bhutta|editor1-first=Zulfiqar A|last=Effa|first=EE |author2=Lassi, ZS |author3=Critchley, JA |author4=Garner, P |author5=Sinclair, D |author6=Olliaro, PL |author7=Bhutta, ZA|title=Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever).|journal=Cochrane Database of Systematic Reviews |date=5 October 2011 |volume=2011 |issue=10|pages=CD004530|pmid=21975746|pmc=6532575|doi=10.1002/14651858.CD004530.pub4|url=https://ecommons.aku.edu/cgi/viewcontent.cgi?article=1078&context=pakistan_fhs_mc_women_childhealth_paediatr}}</ref> and ''Giardia'' species.<ref name=Giar2010/> In those with ''[[Giardia]]'' species or ''Entamoeba histolytica'', [[tinidazole]] treatment is recommended and superior to metronidazole.<ref name=Giar2010/><ref>{{Cite journal|last1=Gonzales|first1=Maria Liza M.|last2=Dans|first2=Leonila F.|last3=Sio-Aguilar|first3=Juliet|date=9 January 2019|title=Antiamoebic drugs for treating amoebic colitis|journal=The Cochrane Database of Systematic Reviews|volume=1|issue=1 |pages=CD006085|doi=10.1002/14651858.CD006085.pub3|issn=1469-493X|pmc=6326239|pmid=30624763}}</ref> The [[World Health Organization]] (WHO) recommends the use of antibiotics in young children who have both bloody diarrhea and fever.<ref name=EBMED2010/>

===Antimotility agents===
Antimotility medication has a theoretical risk of causing complications, and although clinical experience has shown this to be unlikely,<ref name="Oxford"/> these drugs are discouraged in people with bloody diarrhea or diarrhea that is complicated by fever.<ref name="Harrison">{{cite book |title=Harrison's Principles of Internal Medicine |publisher=McGraw-Hill |isbn=978-0-07-140235-4 |edition=16th |url=http://books.mcgraw-hill.com/medical/harrisons/ |url-status=dead |archive-url=https://web.archive.org/web/20120804162006/http://books.mcgraw-hill.com/medical/harrisons/ |archive-date=2012-08-04 |year=2005 |access-date=2006-04-22 }}</ref> [[Loperamide]], an [[opioid]] analogue, is commonly used for the symptomatic treatment of diarrhea.<ref name="SleisengerFordtran">{{cite book |first1=Mark |last1=Feldman |first2=Lawrence S. |last2=Friedman |first3=Marvin H. |last3=Sleisenger |title=Sleisenger & Fordtran's Gastrointestinal and Liver Disease |publisher=Saunders |year=2002 |isbn=978-0-7216-8973-9 |edition=7th |url=https://archive.org/details/sleisengerfordtr0001unse |url-access=registration }}</ref> Loperamide is not recommended in children, however, as it may cross the immature blood–brain barrier and cause toxicity. [[Bismuth subsalicylate]], an insoluble complex of trivalent [[bismuth]] and salicylate, can be used in mild to moderate cases,<ref name="Oxford"/> but [[salicylate toxicity]] is theoretically possible.<ref name=EBMED2010/>

==Epidemiology==
[[File:Diarrhoeal diseases world map-Deaths per million persons-WHO2012.svg|thumb|upright=1.4|Deaths due to diarrhoeal diseases per million persons in 2012 {{Div col|small=yes|colwidth=10em}}{{legend|#ffff20|0–2}}{{legend|#ffe820|3–10}}{{legend|#ffd820|11–18}}{{legend|#ffc020|19–30}}{{legend|#ffa020|31–46}}{{legend|#ff9a20|47–80}}{{legend|#f08015|81–221}}{{legend|#e06815|222–450}}{{legend|#d85010|451–606}}{{legend|#d02010|607–1799}}{{div col end}}]]
[[File:Diarrhoeal diseases world map - DALY - WHO2004.svg|thumb|upright=1.4|[[Disability-adjusted life year]] for diarrhea per 100,000&nbsp;inhabitants in 2004
{{Col-begin}}
{{Col-break}}
{{legend|#b3b3b3|<small>no data</small>}}
{{legend|#ffff65|<small>≤500</small>}}
{{legend|#fff200|<small>500–1000</small>}}
{{legend|#ffdc00|<small>1000–1500</small>}}
{{legend|#ffc600|<small>1500–2000</small>}}
{{legend|#ffb000|<small>2000–2500</small>}}
{{legend|#ff9a00|<small>2500–3000</small>}}
{{Col-break}}
{{legend|#ff8400|<small>3000–3500</small>}}
{{legend|#ff6e00|<small>3500–4000</small>}}
{{legend|#ff5800|<small>4000–4500</small>}}
{{legend|#ff4200|<small>4500–5000</small>}}
{{legend|#ff2c00|<small>5000–6000</small>}}
{{legend|#cb0000|<small>≥6000</small>}}
{{col-end}}]]
It is estimated that there were two billion cases of gastroenteritis that resulted in 1.3&nbsp;million deaths globally in 2015.<ref name=GBD2015Pre/><ref name=GBD2015De/> Children and those in the [[developing world]] are most commonly affected.<ref name=Web09/> As of 2011, in those younger than five, there were about 1.7&nbsp;billion cases resulting in 0.7&nbsp;million deaths,<ref name=Walk2013/> with most of these occurring in the world's poorest nations.<ref name=M93/> More than 450,000 of these fatalities are due to rotavirus in children under five years of age.<ref name=Rota2012/><ref>{{cite journal|last=World Health Organization|title=Global networks for surveillance of rotavirus gastroenteritis, 2001–2008|journal=Weekly Epidemiological Record|date=November 2008|volume=83|issue=47|pages=421–428|url=https://www.who.int/wer/2008/wer8347.pdf|access-date=10 May 2012|pmid=19024780|url-status=live|archive-url=https://web.archive.org/web/20120709014120/http://www.who.int/wer/2008/wer8347.pdf|archive-date=9 July 2012}}</ref> [[Cholera]] causes about three to five million cases of disease and kills approximately 100,000 people yearly.<ref name=Cholera11/> In the developing world, children less than two years of age frequently get six or more infections a year that result in significant gastroenteritis.<ref name=M93/> It is less common in adults, partly due to the development of acquired [[immunity (medical)|immunity]].<ref name=Eck2011/>

In 1980, gastroenteritis from all causes caused 4.6&nbsp;million deaths in children, with the majority occurring in the developing world.<ref name="Mandell">{{cite book |first1=Gerald L. |last1=Mandell |first2=John E. |last2=Bennett |first3=Raphael |last3=Dolin |title=Mandell's Principles and Practices of Infection Diseases |publisher=Churchill Livingstone |year=2004 |isbn=978-0-443-06643-6 |edition=6th |url=http://www.ppidonline.com/ |url-status=dead |archive-url=https://web.archive.org/web/20131018175309/http://www.ppidonline.com/ |archive-date=2013-10-18 |access-date=2006-04-22 }}</ref> Death rates were reduced significantly (to approximately 1.5&nbsp;million deaths annually) by 2000, largely due to the introduction and widespread use of [[oral rehydration therapy]].<ref name="Victora2000">{{cite journal |vauthors=Victora CG, Bryce J, Fontaine O, Monasch R |title=Reducing deaths from diarrhoea through oral rehydration therapy |journal=Bulletin of the World Health Organization |volume=78|issue=10 |pages=1246–55 |year=2000 |pmid=11100619 |pmc=2560623 }}</ref> In the US, infections causing gastroenteritis are the second most common infection (after the [[common cold]]), and they result in between 200 and 375&nbsp;million cases of acute diarrhea<ref name=M93/><ref name=Eck2011/> and approximately ten thousand deaths annually,<ref name=M93/> with 150 to 300 of these deaths in children less than five years of age.<ref name=EBMED2010/>

==Society and culture==
Gastroenteritis is associated with many colloquial names, including "[[Montezuma's revenge]]", "Delhi belly", "la turista", and "back door sprint", among others.<ref name=M93/> It has played a role in many military campaigns and is believed to be the origin of the term "no guts no glory".<ref name=M93/>

Gastroenteritis is the main reason for 3.7&nbsp;million visits to physicians a year in the United States<ref name=EBMED2010/> and 3&nbsp;million visits in France.<ref>{{cite journal|last=Flahault|first=A|author2=Hanslik, T|title=[Epidemiology of viral gastroenteritis in France and Europe].|journal=Bulletin de l'Académie Nationale de Médecine|date=November 2010 |volume=194|issue=8|pages=1415–24; discussion 1424–5|pmid=22046706|doi=10.1016/S0001-4079(19)32172-7|url=http://archive-ouverte.unige.ch/unige:47039|doi-access=free}}</ref> In the United States gastroenteritis as a whole is believed to result in costs of US$23&nbsp;billion per year,<ref>{{cite book |editor1-last=Skolnik |editor1-first=Neil S. |editor2-last=Albert |editor2-first=Ross H. |title=Essential infectious disease topics for primary care|year=2008|publisher=Humana Press|location=Totowa, NJ|isbn=978-1-58829-520-0|pages=66|url=https://books.google.com/books?id=iGUKPeO9-ygC&pg=PA66|url-status=live|archive-url=https://web.archive.org/web/20151128094307/https://books.google.com/books?id=iGUKPeO9-ygC&pg=PA66|archive-date=2015-11-28}}</ref> with rotavirus alone resulting in estimated costs of US$1&nbsp;billion a year.<ref name=EBMED2010/>

== Terminology ==
{{Anchor|Cholera morbus}}
The first usage of "gastroenteritis" was in 1825.<ref>{{cite web|title=Gastroenteritis|url=http://www.oed.com/|url-status=live|archive-url=https://web.archive.org/web/20080111125659/http://www.oed.com/|archive-date=January 11, 2008|access-date=January 15, 2012|work=[[Oxford English Dictionary]] 2011}}</ref> Before this time it was commonly known as [[typhoid fever]] or "cholera morbus", among others, or less specifically as "griping of the guts", "surfeit", "flux", "colic", "bowel complaint", or any one of several other archaic names for acute diarrhea.<ref name="archaic">[http://www.antiquusmorbus.com/English/English.htm Rudy's List of Archaic Medical Terms] {{webarchive|url=https://web.archive.org/web/20070709111154/http://www.antiquusmorbus.com/English/English.htm|date=2007-07-09}}</ref> Cholera morbus is a historical term that was used to refer to gastroenteritis rather than specifically [[cholera]].<ref>{{cite book|author1=Charles E. Rosenberg|url=https://books.google.com/books?id=k2pL9c00rl4C&pg=PA74|title=The Cholera Years the United States in 1832, 1849, and 1866|date=2009|publisher=University of Chicago Press|isbn=978-0-226-72676-2|location=Chicago|page=74|archive-url=https://web.archive.org/web/20151109080652/https://books.google.com/books?id=k2pL9c00rl4C&pg=PA74|archive-date=2015-11-09|url-status=live}}</ref>

==Animals==
Many of the same agents cause gastroenteritis in cats and dogs as in humans. The most common organisms are ''Campylobacter'', ''Clostridioides difficile'', ''Clostridium perfringens'', and ''Salmonella''.<ref>{{cite journal|last=Weese |first=JS |title=Bacterial enteritis in dogs and cats: diagnosis, therapy, and zoonotic potential|journal=Veterinary Clinics of North America: Small Animal Practice|date=March 2011 |volume=41|issue=2|pages=287–309|pmid=21486637 |doi=10.1016/j.cvsm.2010.12.005}}</ref> A large number of toxic plants may also cause symptoms.<ref>{{cite book |last=Rousseaux |first=Wanda Haschek, Matthew Wallig, Colin |title=Fundamentals of toxicologic pathology |year=2009 |publisher=Academic |location=London |isbn=978-0-12-370469-6 |page=182 |url=https://books.google.com/books?id=vkox3JS83k8C&pg=PA182 |edition=2nd |url-status=live |archive-url=https://web.archive.org/web/20160507004136/https://books.google.com/books?id=vkox3JS83k8C&pg=PA182 |archive-date=2016-05-07 }}</ref>

Some agents are more specific to a certain species. [[Transmissible gastroenteritis coronavirus]] (TGEV) occurs in pigs resulting in vomiting, diarrhea, and dehydration.<ref>{{cite book |editor1-last=MacLachlan |editor1-first=N. James |editor2-last=Dubovi |editor2-first=Edward J. |year=2009 |title=Fenner's veterinary virology|publisher=Elsevier Academic Press|location=Amsterdam|page=399|isbn=978-0-12-375158-4|edition=4th |url=https://books.google.com/books?id=TYFqlYO9eE4C&pg=PA399|url-status=live|archive-url=https://web.archive.org/web/20151125122358/https://books.google.com/books?id=TYFqlYO9eE4C&pg=PA399|archive-date=2015-11-25}}</ref> It is believed to be introduced to pigs by wild birds and there is no specific treatment available.<ref>{{cite book |editor1-first=James G. |editor1-last=Fox |title=Laboratory animal medicine |year=2002 |publisher=Academic Press |location=Amsterdam |isbn=978-0-12-263951-7 |page=649 |url=https://books.google.com/books?id=m2ftfPMJnMMC&pg=PA649 |edition=2nd |display-editors=etal |url-status=live |archive-url=https://web.archive.org/web/20151128151809/https://books.google.com/books?id=m2ftfPMJnMMC&pg=PA649 |archive-date=2015-11-28 }}</ref> It is not transmissible to humans.<ref name="ZimmermanKarriker2012">{{cite book|last1=Zimmerman|first1=Jeffrey|last2=Karriker|first2=Locke|last3=Ramirez|first3=Alejandro|author4=Kent Schwartz|author5=Gregory Stevenson|title=Diseases of Swine|url=https://books.google.com/books?id=jVaemau17J4C&pg=PA504|date=15 May 2012|publisher=John Wiley & Sons|location=Chichester, West Sussex|edition=10th|isbn=978-0-8138-2267-9|page=504|url-status=live|archive-url=https://web.archive.org/web/20151128142144/https://books.google.com/books?id=jVaemau17J4C&pg=PA504|archive-date=28 November 2015}}</ref>

==See also==
*[[Enterocolitis]]

==References==
{{Reflist}}

===Notes===
* {{cite book |editor1-last=Dolin |editor1-first=Raphael |editor2-last=Mandell |editor2-first=Gerald L. |editor3-last=Bennett |editor3-first=John E. |year=2010 |title=Mandell, Douglas, and Bennett's principles and practice of infectious diseases |publisher=Churchill Livingstone/Elsevier|location=Philadelphia|isbn=978-0-443-06839-3|edition=7th |ref={{harvid|Mandell|2010}}}}

==External links==
{{commons category}}
* [https://www.ncbi.nlm.nih.gov/books/NBK63841/ Diarrhoea and Vomiting Caused by Gastroenteritis: Diagnosis, Assessment and Management in Children Younger than 5 Years] – NICE Clinical Guidelines, No. 84.
* {{cite web | url = https://medlineplus.gov/gastroenteritis.html | publisher = U.S. National Library of Medicine | work = MedlinePlus | title = Gastroenteritis }}

{{Medical condition classification and resources
 | DiseasesDB     = 30726
 | ICD10          = {{ICD10|A|02|0|a|00}}, {{ICD10|A|08||a|00}}, {{ICD10|A|09||a|00}}, {{ICD10|J|10|8|j|09}}, {{ICD10|J|11|8|j|09}}, {{ICD10|K|52||k|50}}
 | ICD9           = {{ICD9|008.8}} {{ICD9|009.0}}, {{ICD9|009.1}}, {{ICD9|558}}
 | ICDO           =
 | OMIM           =
 | MedlinePlus    = 000252
 | MedlinePlus_mult= {{MedlinePlus2|000254}}
 | eMedicineSubj  = emerg
 | eMedicineTopic = 213
 | MeshID         = D005759
}}
{{Gastroenterology}}
{{Viral diseases}}
{{Authority control}}

[[Category:Pediatrics]]
[[Category:Foodborne illnesses]]
[[Category:Infectious diseases]]
[[Category:Abdominal pain]]
[[Category:Conditions diagnosed by stool test]]
[[Category:Noninfective enteritis and colitis]]
[[Category:Diarrhea]]
[[Category:Wikipedia medicine articles ready to translate (full)]]
[[Category:Sanitation]]
[[Category:Wikipedia emergency medicine articles ready to translate]]