A condition caused when the body does not have enough red blood cells or hemoglobin. Hemoglobin is a protein in the blood that carries oxygen.

A surgical connection of two body parts. An example is an operation in which part of the colon is removed and the two remaining ends are joined.

A passage that develops between the anus and the skin. Most fistulas are the result of an abscess or infection that spreads to the skin. Fistulas are typical of Crohn

A small tear in the anus that may cause itching, pain, or bleeding.

The opening of the common bile duct and pancreatic duct into the duodenum. Also called papilla of Vater.

A group of 20 different kinds of small molecules that link together in chains to form proteins. Often referred to as the “building blocks” of proteins. An amino acid is an organic compound composed of both an amino (NH2) group ...

An acute or chronic infection caused by amoebas, a type of parasite. Symptoms vary from mild diarrhea to frequent, watery diarrhea and loss of water and fluids in the body. See gastroenteritis.

An immune response to a foreign antigen that results in inflammation and organ dysfunction. IgE (immunoglobulin E) antibody tests (blood tests) is used to diagnose an allergy. Allergies can range from life threatening to annoying and include systemic anaphylaxis, throat ...

One of the variant forms of a gene at a particular locus, or location, on a chromosome. Different alleles produce variation in inherited characteristics such as hair color or blood type. In an individual, one form of the allele (the ...

The development of inflammation of the esophagus due to prolonged contact of the esophagus with non-acidic, that is, alkaline gastric contents.

An inherited condition causing a lack of the enzyme needed to digest milk sugar, which is lactose.

A condition that occurs when a person swallows too much air, causing gas in the stomach and frequent belching.

Viruses that cause gastroenteritis and respiratory infection. Vomiting and diarrhea appear about 1 week after exposure. Infections occur all year round and most often in children less than 2 years old.

Refers to conditions that happen suddenly and last a short time. Acute is the opposite of chronic, or long lasting.

A lack of hydrochloric acid in the digestive juices of the stomach.