Foreign body

Overview
In physiology, a foreign body (Latin: corpus alienum) is any object originating outside the body. In machinery, it can mean any unwanted intruding object.

In Man
Foreign bodies typically become lodged in the eyes, ears, nose, airways, and rectum which are the main orifices of human beings. Foreign bodies can be in hollow organs (like swallowed batteries) or in tissues (like bullets). They can be inert or irritating. If they irritate they will cause inflammation and scarring. They can bring infection into the body or acquire infectious agents and protect them from the body's immune defenses. They can obstruct passageways either by their size or by the scarring they cause. Some can be toxic.

Both children and adults experience problems caused by foreign objects getting stuck in their bodies. Young children, in particular, are naturally curious and may intentionally put shiny objects, such as coins or button batteries, into their mouths. They also like to stick things in their ears and up their noses. Adults may accidentally swallow a non-food object or inhale a foreign body that gets stuck in the throat. Airborne particles can lodge in the eyes of people at any age. These foreign bodies often result in allergies which are either temporary or even turn into a chronic allergy. This is especially evident in the case of dust particles.

Most objects that are swallowed will, if they have passed the pharynx, pass all the way through the gastrointestinal tract. Rarely an object becomes arrested (usually in the terminal ileum or the rectum) or a sharp object penetrates the bowel wall. If the person who swallowed the foreign body is doing well, usually a x-ray image will be taken which will show any metal objects, and this will be repeated a few days later to confirm that the object has passed all the way through the digestive system. Also it needs to be confirmed that the object is not stuck in the airways, in the bronchial tree. If the foreign body causes problems like pain, vomiting or bleeding it must be removed. Also swallowed mercury batteries should be removed as soon as possible as they are very dangerous especially to small children.