Fundamentals of Anatomy and Physiology

Nutrition and the Digestive System 395

Common Disease, Disorder, or Condition

Disorders of The Digestive System continued

symptoms can indicate this condition, including blood in the feces, abdominal pain, and

a change in the consistency and frequency of bowel movements. A hemoccult test

should become a normal part of yearly physicals to detect any blood in the fe-ces.

Some colon cancers take years to develop. Intestinal cells begin to divide more

frequently than normal. They may form benign polyps at first and then lead to ma-

lignant growths. In severe cases, sections of the intestine may be removed surgically

with a new opening created to exit the feces. This procedure is called a colostomy and

the patient must wear a colostomy bag to collect and dispose of the fecal material.

Hemorrhoids^
Hemorrhoids, or piles, are caused by the inflammation and enlargement of rectal
veins. Those that are initially contained within the anus are known as first-degree
hemorrhoids. If these enlarge so that they extend outward on defecation (prolapse),
they are then called second-degree hemorrhoids. When they finally are so enlarged that
they remain prolapsed through the anal opening, they are called third-degree
hemorrhoids and usually require surgical removal. Strain on defecation causes in-
flammation of these veins. A diet rich in fiber helps produce softer stools, which results
in less strain on defecation.

Diarrhea^
Diarrhea (dye-ah-REE-ah) literally means a flowing through. It occurs when the mu-
cosa of the colon is unable to maintain its usual levels of water absorption and se-cretes
larger than normal amounts of water, ions, and mucus. Food poisoning with bacteria of
the salmonella group, certain viral infections like those that cause intes-tinal flu, and
protozoan infections with the amoeba Entamoeba histolytica caused by drinking
untreated water causes bouts of severe diarrhea called dysentery. These organisms
invade the intestinal lining and destroy the normal cells that carry on the absorption of
water. The excessive loss of water caused by bouts of diarrhea can lead to serious
dehydration. Without proper treatment, a victim could die. Diarrhea is a common cause
of death in young children in poor, undeveloped countries.

Thrush^
Thrush is a fungal infection of the tissues of the mouth caused by Candida albicans
(Figure 16-16). It can also infect the skin, intestines, and the vagina of women. In the
mouth, it is called oral candidiasis. It is characterized by creamy white plaques on the
mucous membrane lining of the mouth. It is more common in children and is usually
benign and can be treated with medications. In adults who have human
immunodeficiency virus (HIV), it is a common opportunistic infection that can spread to
the esophagus.

Food Poisoning^
Food poisoning is caused by the digestion of food contaminated with the bacteria
Salmonella, resulting in salmonellosis (SAL-mon-el-OH-sis). There is an incubation
period of 6 to 48 hours, which is followed by bouts of abdominal pain, diarrhea, fe-ver,
and nausea. There is no specific treatment other than prevention by adequately cooking
food, keeping cooked food refrigerated, and thorough washing of one’s hands before
eating. Symptoms may persist anywhere from 4 to 7 days. Frequent diarrhea may lead
to dehydration.