Dysentery Causes 101 – Why Amoebic Dysentery Is Caused

Dysentery can be either bacterial or amoebic, depending on the type of infection and the microorganism involved. When it comes to amoebic dysentery, the causes can be narrowed down to Entamoeba histolytica – a single-celled protozoan parasite that infects the large intestine, bringing about bloody diarrhea.

dysentery causes

Transfer of the dysentery parasite from an infected person to a normal one is one of the common dysentery causes.

This microorganism breeds in specific reservoirs and is spread through certain carriers.

  • Reservoirs

    Infected humans and people who carry the parasite asymptomatically are the only reservoirs.

  • Carriers

    Food or water that has been contaminated with the infection through the feces (stool) of infected individuals act as the carriers of this infection.
    The infection can also spread through oral or anal sexual contact and due to poor personal hygiene.

Dysentery Causes – The Role Of Fomites

Any object that acts as a vehicle for transmitting amoebic dysentery is called as a fomite. For example, when a person with dysentery touches the door handle without washing his hands after defecating, he can transfer the organism onto the door handle.

When a second healthy person touches the door handle and later uses his hands for eating, the organism enters his digestive system and infects the bowels.

Dysentery Causes – How The Amoeba Causes Dysentery

Entamoeba histolytica enters the body in two forms, and this can determine the extent of the infection.

  • Tropozoite (Free Amoeba)

    Active growing form that is readily killed by the digestive enzymes or the acidity of the stomach.

  • Cyst (Egg-Like Stage)

    Infectious form that comes with a protective covering, is resistant to adverse environmental conditions, and is excreted in the feces of affected individuals.

Amoebic dysentery is caused when the cyst form of the parasite is ingested. Once inside the human intestinal tract, it bypasses the adverse acidic condition of the stomach, enters a favorable environment, and resumes its growth, causing damage to the intestine.

In severe cases, the organism invades the intestinal wall causing dysentery and may also reach other organs through the blood stream causing extra-intestinal complications like liver damage.

Some of the tropozoites get excreted in feces, ready to infect a second person. These cysts survive for long periods (up to two months) in the environment and contaminate adjacent water bodies or cultivation, serving as potential sources of infection and acting as primary dysentery causes.

The cysts can also remain inactive in the intestine for years and trigger the disease when a person’s immunity is low, during pregnancy, old age, or when patients are affected by cancer, diabetes, alcoholism, or a HIV infection.

Dysentery Causes – Predisposing Factors

When it comes to dysentery causes, some factors that play a key role are:

  • Using untreated human waste as fertilizers
  • Untreated sewage getting to drinking water
  • Travelling to developing countries without adequate precautions
  • Eating contaminated fruits and vegetables
  • Drinking water without treating it beforehand
  • Poor sanitation and personal hygiene
  • Washing fruits or vegetables in contaminated water
  • Living in crowded areas like refugee camps

Amoebiasis occurs worldwide, but dysentery symptoms are quite a common problem in Africa, Mexico, certain parts of South America, and South East Asia (including India). They account for about 70,000 deaths annually worldwide, so learning about the dysentery causes and taking active measures for dysentery prevention can keep you on the safer side of the fence. In case you do do contract this infection, consult your doctor for a confirmation of dysentery diagnosis as well as timely amoebic dysentery treatment.

Amoebic Dysentery – An Introduction To The Condition

Amoebic Dysentery (Amoebiasis) is an infection of the large intestine caused primarily by a single celled protozoan parasite (amoeba) called Entamoeba histolytica. Dysentery symptoms include severe diarrhea, blood and mucus in the feces, mild fever, and stomach pain.

Amoebic dysentery accounts for 70,000 deaths occurring annually around the globe.

amoebic dysentery

The protozoan parasite called Entamoeba Histolytica causes amoebic dysentery.

How Does Amoebic Dysentery Spread?

The infection is acquired by the ingestion (swallowing) of food or water that has been contaminated by the feces of infected individuals who shed the organism (cyst or egg like stage of the parasite) in their feces.

Poor personal hygiene, unsafe drinking water, oral-anal sexual contact, and uncooked food items are the main factors that play a role in spreading the disease.

The Progression Of Amoebic Dysentery

Once the organism enters the human digestive tract, it takes 7–28 days to trigger visible clinical symptoms.

In a majority of the cases, the infection presents itself as a milder form with or without symptoms. But in 20% of the cases, it can cause severe invasive infection of the liver or other organs, causing complications that require serious medical attention.

Stool that is released from the bowel with streaks of blood is a characteristic feature of amoebic dysentery. Other symptoms include abdominal tenderness, stomach pain, nausea, excessive gas, fatigue, liver abscess, mild fever, an enlarged liver, and jaundice.

Massive diarrhea due to the disease also leads to dehydration. Immunocompromised (individuals with low immunity such as HIV patients, malnourished individuals, diabetics etc) face a greater risk of developing complications.

Identifying The Presence Of Amoebic Dysentery

Dysentery diagnosis involves the collection of at least 3 fresh stool samples over a period of 2-3 days. These samples are then sent to the laboratory for confirmation of the infection.

The appearance of ova (cyst) and parasitic forms of amoeba under microscopic examination is taken as the confirmation for amoebiasis. Alternately, doctors also check the blood for antibodies in order to confirm the diagnosis. Other measures like a CT scan, MRI scan, and colonoscopy aid in diagnosing the disease.

How Amoebic Dysentery Is Treated

Treatment is to be started only after consulting a doctor. Metronidazole or tinidazole is administered to patients who suffer from amoebic dysentery, followed by a 10 day course of diloxanide furoate.

Fluid and electrolyte replacement, either through ORS solutions or intravenous administration, should be taken care of in order to prevent dehydration. Liver abscess can be drained or aspirated to prevent its rupture.

Can Amoebic Dysentery Be Prevented?

Definitely! Proper dysentery prevention measures can help you avoid the onset of amoebic dysentery.

Washing your hands thoroughly after using toilets and before eating or preparing food, drinking sterilized (boiled) water, disposing your sewage properly, refraining from anal intercourse, and avoiding raw or uncooked foods from street vendors can help you prevent amoebic dysentery. If dysentery causes have already resulted in the infection, it is advisable to seek immediate amoebic dysentery treatment.