Barrett's esophagus is a condition in which the tissue lining the esophagus the muscular tube that connects the mouth to the stomach is replaced by tissue that is similar to the lining of the intestine. This process is called intestinal metaplasia. No signs or symptoms are associated with Barrett's esophagus, but it is commonly found in people with gastroesophageal reflux disease (GERD). A small number of people with Barrett's esophagus develop a rare but often deadly type of cancer of the esophagus.

http://my.clevelandclinic.org/disorders/Barretts_Esophagus/

http://www.acg.gi.org/patients/gihealth/barretts.asp

Celiac Disease

Celiac disease is a condition in which the immune system responds abnormally to proteins found in wheat, rye, barley, and a multitude of prepared foods. These proteins are called gluten. When ingested, gluten can cause damage to the lining of the small intestine.

http://www.csaceliacs.org/

http://www.celiac.nih.gov/

http://digestive.niddk.nih.gov/ddiseases/pubs/celiac/

Chronic Constipation

Chronic constipation is diagnosed when a person has had less than three bowel movements in a week, or has great difficulty in passing stool.

http://www.mayoclinic.org/constipation/

http://digestive.niddk.nih.gov/ddiseases/pubs/constipation/

Cirrhosis

Cirrhosis is a slowly progressing disease in which healthy liver tissue is replaced with scar tissue, eventually preventing the liver from functioning properly.

http://digestive.niddk.nih.gov/ddiseases/pubs/cirrhosis/

Clostridium difficile Infection

Clostridium difficile, also called c.diff, is a bacteria that can cause symptoms ranging from diarrhea to life-threatening inflammation of the colon. It commonly affects older adults in hospitals or in long term care facilities, and typically occurs after use of antibiotic medications.

http://www.mayoclinic.com/health/c-difficile/DS00736

Colon Polyps

Colon polyps are growths in your large intestine. Most colon polyps are harmless, but some can turn into colon cancer.

http://digestive.niddk.nih.gov/ddiseases/pubs/colonpolyps_ez/

Colon Cancer

Colon and rectal cancer are cancers that involve the lowest part of the digestive system--the large intestine and the rectum. The most common symptoms of colorectal cancer include: stomach pain, change in bowel habits (constipation or diarrhea), and blood in the bowel movements (microscopic or overt), feeling weak or tired and iron deficiency anemia.

http://www.mayoclinic.com/health/colon-cancer/DS00035

Crohn's Disease

Crohn's disease is an inflammatory condition of the digestive tract that affects children and adults. Common features of Crohn's disease include mouth sores, diarrhea, abdominal pain, weight loss, and fever. Patients can also have problems outside of the digestive tract, including a skin rash, joint pain, eye redness, and, less commonly, liver problems.

http://www.ccfa.org/info/about/crohns

http://digestive.niddk.nih.gov/ddiseases/pubs/crohns/

http://www.mayoclinic.com/health/crohns-disease/DS00104

Diverticulosis/Diverticulitis

Diverticular Disease is the condition in which small pouches have formed in the lining of the colon wall, most commonly in the sigmoid colon. The diverticula have the potential of becoming infected and this condition is called diverticulitis.

http://www.webmd.com/digestive-disorders/tc/diverticulosis-topic-overview

Eosinophilic Esophagitis

Eosinophilic esophagitis, or allergic esophagitis, is characterized by eosinophilic infiltration of the esophagus presumably due to allergic or idiopathic causes. It can occur in adults and children and can produce symptoms of reflux, trouble swallowing, or food impactions.

http://www.apfed.org/ee.htm

http://www.mayoclinic.org/eosinophilic-esophagitis/

Fatty Liver (nonalcoholic fatty liver disease)

Fatty liver is the build-up of excess fat in the liver cells usually diagnosed with an ultrasound. If fat accounts for more than 10% of your liver's weight, then you have fatty liver, and you may develop more serious complications.

http://www.mayoclinic.com/health/nonalcoholic-fatty-liver-disease/DS00577

Gallbladder and Biliary Disease

Gallbladder and Biliary disease includes a spectrum of disorders caused by abnormalities in bile composition, biliary anatomy, or function. This includes gallstones (cholelithiasis), infection of the gallbladder (cholecytitis), and abnormal function of the gallbladder (biliary dyskinesia).

http://www.nlm.nih.gov/medlineplus/ency/article/001138.htm

Gas & Bloating

Bloating, burping and passing gas are natural and are often caused by swallowed air or the breakdown of food through digestion. In some cases, although uncommon, it can be an indication of disease.

http://www.webmd.com/heartburn-gerd/tc/gas-bloating-and-burping-topic-overview

Gastroparesis

Gastroparesis is a condition in which the muscles in your stomach do not function normally, and it can prevent your stomach from emptying properly. It can cause nausea and vomiting, and affect your nutrition.

http://digestive.niddk.nih.gov/ddiseases/pubs/gastroparesis/

http://www.mayoclinic.com/health/gastroparesis/DS00612

GERD (gastroesophageal reflux disease)

Gastroesophageal reflux, also known as acid reflux, occurs when the stomach contents reflux or back up into the esophagus and/or mouth. Symptoms can include heartburn, vomiting, or pain with swallowing.

http://www.nlm.nih.gov/medlineplus/ency/article/000265.htm

http://www.webmd.com/heartburn-gerd/default.htm

Helicobacter Pylori infection

Helicobacter pylori, also known as H. pylori, are bacteria that are commonly found in the stomach. It can cause symptoms of nausea, indigestion, and ulcers of the stomach can develop in some cases.

http://www.mayoclinic.com/health/h-pylori/DS00958

Hemorrhoids

Hemorrhoids are enlarged or swollen veins in the lower rectum. The most common symptoms are rectal bleeding, itching, and pain.

http://www.webmd.com/a-to-z-guides/hemorrhoids-topic-overview

http://www.mayoclinic.com/health/hemorrhoids/DS00096

http://digestive.niddk.nih.gov/ddiseases/pubs/hemorrhoids/

Hepatitis, Autoimmune

Autoimmune hepatitis is a disease in which the body's immune system attacks liver cells. It is typically chronic and can lead to cirrhosis, scarring of the liver and possibly liver failure.

http://www.hepatitis-central.com/hcv/autoimmune/toc.html

Hepatitis A

Hepatitis A is a virus that is spread primarily through food or water contaminated by feces from an infected person. It usually resolves on its own over several weeks.

http://www.webmd.com/hepatitis/hepa-guide/default.htm

http://www.cdc.gov/hepatitis/PublicInfo.htm

Hepatitis B

Hepatitis B is a virus spread through contact with infected blood, through sex with an infected person, and from mother to child during childbirth, whether the delivery is vaginal or via cesarean section.

http://www.webmd.com/hepatitis/hepb-guide/default.htm

http://www.cdc.gov/hepatitis/PublicInfo.htm

Hepatitis C

Hepatitis C is a virus spread primarily through contact with infected blood. People most likely to be exposed to the hepatitis C virus are injection drug use, infants born to infected mothers, hemodialysis patients, people who received a transfusion of blood or blood products before July 1992, and people who received clotting factors made before 1987.

http://www.cdc.gov/hepatitis/PublicInfo.htm

http://www.mayoclinic.com/health/hepatitis-c/DS00097

Hepatitis, drug-induced

Drug-induced hepatitis is inflammation of the liver that may occur when you take certain medications. It is the most common cause of acute liver failure.

http://www.nlm.nih.gov/medlineplus/ency/article/000226.htm

Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic condition of the digestive system. Its primary symptoms are abdominal pain and altered bowel habits (i.e. constipation and/or diarrhea), but these symptoms have no identifiable cause.

http://my.clevelandclinic.org/disorders/Irritable_Bowel_Syndrome_IBS/

http://digestive.niddk.nih.gov/ddiseases/pubs/ibs/

Lactose intolerance

Lactose intolerance is the inability to digest lactose (a type of sugar found in milk and other dairy products).

http://digestive.niddk.nih.gov/ddiseases/pubs/lactoseintolerance/index.htm

Microscopic Colitis

Microscopic colitis takes two forms: collagenous colitis and lymphocytic colitis. Collagenous colitis and lymphocytic colitis are two types of bowel inflammation that affect the colon (large intestine).

http://my.clevelandclinic.org/disorders/microscopic_colitis/dd_overview.aspx

Nonalcoholic Steatohepatitis (NASH)

Nonalcoholic steatohepatitis (NASH) is a condition that causes inflammation and accumulation of fat and fibrous tissue in the liver.

http://digestive.niddk.nih.gov/ddiseases/pubs/nash/

http://www.webmd.com/digestive-disorders/tc/nonalcoholic-steatohepatitis-nash-overview

Pancreatitis

Pancreatitis is a disease in which the pancreas becomes inflamed. It can be acute or chronic.

http://digestive.niddk.nih.gov/ddiseases/pubs/pancreatitis/

http://www.mayoclinic.com/health/pancreatitis/DS00371

Peptic Ulcer Disease

Peptic ulcer disease refers to ulcers or erosions in the lining of the stomach or first part of the small intestine, called the duodenum.

http://www.webmd.com/digestive-disorders/digestive-diseases-peptic-ulcer-disease

Ulcerative Colitis

Ulcerative colitis ( UC ) is a disease in which the lining of the colon (the large intestine) becomes inflamed and develops sores (ulcers), which leads to bleeding and diarrhea.

http://digestive.niddk.nih.gov/ddiseases/pubs/colitis/