Diseases of the Digestive system
The stomach and the oral cavity are part of the digestive system, which is also known as the alimentary or the gastrointestinal tract. The whole system starts from the mouth up to the anus and is divided into the upper and the lower digestive systems (Gad, 2007). The stomach and the oral cavity are found in the upper digestive system as shown in the illustration below.
Diarrhea can be defined as increased stooling or passing of stool whose consistency is more watery than normal (Gad, 2007). It is a common symptom that is caused by infections in the gastrointestinal tract. Diarrhea is also a leading cause of morbidity and mortality all over the world. For a normal functioning gastrointestinal tract, the cavity can absorb fluids and electrolytes from food and drinks, in a manner that follows an osmotic gradient and maintains a balance of ion and water. For instance, while up to 8 liters of fluid are introduced to the gastrointestinal tract daily, only 200g of fluid in passed as stool. However, enteric pathogens can alter this balance causing diarrhea (Gad, 2007).
Various infectious diseases of the stomach and the oral cavity can cause diarrhea; these include:
- Cholera – This is a common disease that causes severe diarrhea. Cholera is caused by Vibrio cholera, a gram negative bacterium that is salt tolerant and can survive in a highly alkaline condition. The common symptom of cholera is severe diarrhea with the loss of up to 20 liters of fluid in a day through loose stools. Other symptoms of cholera include vomiting and muscle cramps that are mostly caused by the excessive loss of fluids. For cholera to infect the stomach, large amounts of the bacteria must be ingested.
- Shigellosis – This is another bacterial infection that is caused by the shigella bacteria. The bacteria can tolerate the stomach acid and could easily multiply in the stomach. The common symptom is dysentery and pus and blood can be found in the stool. Other symptoms of shigellosis include vomiting, headaches, stiff neck, joint pain and stiff neck.
- Escherichia coli gastroenteritis – This is disease is caused by different strains of E. coli that enter the body through contaminated food and water as well as through person to person contact. The common symptom is diarrhea and depending on the infecting strain, an infected person could have few loose stools or severe diarrhea accompanied by muscle cramps and bloody stool. Other symptoms of E. coli gastroenteritis include fever and muscle cramps.
- Salmonellosis – This disease is caused by the salmonella bacterium that is gram negative. The bacterium is sensitive to stomach acid hence a high number is required for a stomach infection to occur. Symptoms of salmonellosis include diarrhea, vomiting, abdominal pain, nausea and fever.
- Other infectious diseases that occur in the stomach that could cause diarrhea include campylobacter, and parasites such as Entamoeba histolytica and Cryptosporidium.
Most of the infections that cause diarrhea occur in the small intestine mainly because the stomach acid rarely tolerates microorganisms. However, the infection discussed above can occur in the stomach if large quantities of the pathogens are ingested (Gad, 2007).
The diarrhea causing pathogens, particularly bacteria are mostly transmitted through fecal matter. This occurs when food and drinks that are contaminated by the fecal matter of an infected person is ingested. The risk factors for diarrhea include poor sanitation and contact with fecal matter prior to handling food.