amoebic dysentery

Amoebic Dysentery: description

The amoebic dysentery is triggered by the unicellular: “Entamoeba histolytica”. She is not the only amoeba that can affect humans, but only she makes him sick. The amoebae who do not (E. dispar, E. moshkovskii) are much more common. The probability of having a non-pathogenic amoeba species is ten times higher than infection with E. histolytica.

Even though approximately 10 percent of all people worldwide carry the parasite, only 70,000 to 100,000 people die each year as a result of the amoebic dysentery (amebiasis). Not every infected person also suffers from the amoebic dysentery. More than 90 percent of parasite carriers never develop symptoms. However, as they excrete spread stages (cysts) in their stools, they are constantly pestering other people. Only when the amoebas manage to leave the gut and enter the bloodstream do they inflict lethal damage on other organs.

What is an amoeba?

An amoeba is a parasite that belongs to the group of protozoa (protozoa). A much more famous protozoan disease is malaria. The amoebic dysentery (amebiasis) is transmitted through the cysts of the amoebae. These spherical survival stages are much more robust than the moving shape of the amoebae, thereby increasing the likelihood of transmission. They dry out slowly outside the intestine and do not need food.

When cysts are consumed by humans, they develop into amoebae in the small intestine and multiply. In the large intestine, the amoebae have two options: either they develop into cysts and are excreted through the stool again, or they attack the intestinal wall. If they are excreted and taken up by another person, the cycle closes.

If the intestinal wall is attacked during the amoebic dysentery, it causes abdominal pain with bloody diarrhea. In rare cases, the amoebae also enter the bloodstream and are trafficked into different organs. Due to the fight between the immune system and the amoeba, a strong formation of pus within the organ occurs. This is what doctors call abscess.

How to deal with the amoebic dysentery?

Infected people are constantly shedding cysts. If these cysts get into drinking water or to foods that are eaten raw, others can get by Consume the contaminated food or water, Most likely, the transmission is via:

• Fruits and raw vegetables
• Water and drinks
• Ice cream or sorbet
• salad

In general, a moist, dark environment is ideal for the cysts. In such a habitat, the cysts survive for several weeks in drinking water or on food. Even short trips to risk countries are enoughto become infected with the amoebic dysentery. In high-risk areas, about half of the local population is infected.

Where does the amoebic dysentery occur?

The amoebic dysentery is transmitted fecally-orally. This means that cysts secreted by the stool have to be ingested with food to infect themselves. Wherever no high standards of hygiene prevail, amoebiasis can be transmitted. This is especially true for developing countries. Often you are in Central and South America, Africa and South Asia, but also in Western countries, it can lead to infection.

Amoebic dysentery: symptoms

Most people who are infected with the amoeba E. histolytica show no symptoms. One speaks in a pure infection without complaints of one Infestation, About ten percent of cases develop a “intestinal amebiasis“, In which the amoebae penetrate into the intestinal wall and populate it. In just one percent of cases, the amoebae enter the bloodstream and colonize organs such as the liver. These organs produce abscesses that restrict organ function and can lead to death. If the parasites from the intestine reach other parts of the body, the doctors speak of a “extraintestinal amebiasis“.

Intestinal amebiasis

Intestinal amebiasis is amoebic dysentery in the narrower sense. The beginning of the amoebic dysentery is rather insidious. One to several weeks after the infection it comes to six to eight times a day to slimy, sometimes bloody diarrhea and abdominal cramps. The chair is frothy or glassy and is often described as raspberry jelly. At times it can also lead to constipation and severe pressure pain in the lower abdomen. In addition to weight loss in severe cases, the amoebic dysentery is also possible for fever and chills.

Since in Western countries other diagnoses such as bacterial diarrhea or appendicitis are more common than the amoebic dysentery, the doctor should always be advised of a tropical trip. If the intestinal amoebiasis is not recognized, the symptoms persist. They are easily confused with inflammatory bowel diseases such as Crohn’s disease, or ulcerative colitis. Both diseases are a malfunction of the immune system against the intestine, which also leads to repeated diarrhea and abdominal pain.

In a misdiagnosis further complications threaten by the amoebic dysentery. The inflammation can cause nodules in the intestinal wall that disturb the passage of the stool. If this is the case, the doctors speak of one ileus, However, it can get even worse: The intestine can also burst open (perforate), which can have serious consequences for the patient and his life. In addition, there is a risk that the amoebae enter the bloodstream and cause extra-intestinal amoebiasis.

Extraintestinal amebiasis

If the amoebas get into the bloodstream, they can reach almost all organs. Most often they migrate from the intestine to the liver. This happens months to years after the infection and can also occur without previous diarrheal symptoms or regular abdominal pain. In the liver the amoebae form one abscess, The physicians call abscess an accumulation of pus in an organ, in which the immune system fights bitterly against a pathogen.

Liver abscess due to amoebic dysentery is associated with high fever and severe pain under the right costal arch. As the pain radiates, the right shoulder or ribs can also hurt. The infection can sometimes break from the liver into the chest and heart. Although the amoebae reach the liver via the intestine, diarrhea occurs in only 30 percent of abscess patients. This means that even without abdominal pain and diarrhea an amoebic infection is possible.

Amoebic dysentery: causes and risk factors

If one looks at all transmission paths of the amoebic dysentery, it becomes clear that the main risk factor lies in the hygienic conditions of the respective region. When traveling to affected regions must be especially on the Hygiene in drinking water and food be respected. Their own behavior in tropical and subtropical countries makes up a large part of the disease risk.

Another way of infection is anal-oral intercourse, A risk group for such a route of infection are men who have sexual intercourse with other men, although of course heterosexual couples can be infected with the same gender practices as well. Here, the cysts pass directly from the rectum into the mouth of the sexual partner.


In addition to homosexual couples, increasingly also become ill:

• small children
• older people
• pregnant woman
• Patients taking cortisone therapy
• immunosuppressed patients
• malnourished people

For these people complications such as a liver abscess are often more serious than for other patients. Early diagnosis and consistent therapy can prevent the spread of amoebae.

Amoebic dysentery: examinations and diagnosis

To diagnose the amoebic dysentery, the doctor has some tests available. If there is a suspicion of infection, you should contact his home or pediatrician to have the appropriate examinations made. Most important is the direct conversation with the patient (anamnese). Exotic travels in the past should also be mentioned as well as the acute complaints. The doctor can ask you the following questions:

• Have you been to tropical countries recently?
• Do you have diarrhea and if so how long?
• Is your diarrhea bloody-slimy?

Even if the stay abroad may have been years ago, the doctor must be informed of the trip so that he can make the suspected diagnosis amoebic dysentery.

A true proof of amoebic dysentery is only one stool specimen possible. However, one does not see in the stool the difference between the malignant E. histolytica and other amoeba species. That’s what it stands for blood test available that can tell the difference. The blood test also becomes important if extraintestinal amoebiasis is suspected. In this case you will not necessarily find cysts in the stool, but only the amoebae in the affected organs. Newer methods allow direct detection of amoebicDNA in the chair.

If the mucous membrane in the intestine is damaged, these injuries can also be caused by a colonoscopy (Colonoscopy). In this examination, the doctor looks with the help of a camera on a flexible rod the intestinal mucosa optically. If other organs than the intestine are affected, you can go with it Ultrasonic and if necessary also one Computed Tomography (CT) see the abscess in a picture.

The doctor does not have to report the amoebic dysentery to the health department. However, if there are cases among his patients, this is very reportable. For example, the legislator is trying to efficiently isolate possible outbreaks of amoebic dysentery in Germany.

Amoebic dysentery: treatment

In the treatment of amoebic dysentery, it plays an important role whether the amoebae have already damaged the intestinal wall, or whether it is a symptomless infestation. Treated belong both, so that it can not come to complications later and to limit the spread of amoebic dysrh as efficiently as possible.

Infestation without symptoms:

If amoebas have been detected in the stool, but there are no symptoms and no evidence of organ damage, antibiotic therapy will suffice paromomycin for at least five days out. The substance is not absorbed into the body, thus killing the amoebae only in the intestine.

Infection of the intestinal wall (intestinal amebiasis):

If the amoebae have attacked the intestinal wall, bloody diarrhea usually occurs. If this is the case, the amoebic dysentery is in addition to paromomycin with metronidazole treated. This is another antibiotic that also kills the amoebae in the intestinal wall because it is absorbed by it.

Amöbenabszess:

If it has come to an abscess, you also use metronidazole, but in larger quantities. To a Surgery or puncture it only happens when the bursting of pus-filled bubble threatens. If the abscess is recognized in good time and treated consistently, it will recover over several weeks. For very severe amoebic infections, the patient may need to be stabilized before any definitive therapy can be started. If the person is really so seriously ill, depending on the organ and the patient, it must be decided how exactly to proceed in order to save the patient’s life.

Amoebic dysentery: disease course and prognosis

The course of amoebic dysentery can be very diverse. Infection with E. histolytica does not make every person ill. Even if you fall ill, the symptoms range from simple diarrhea to a life-threatening liver abscess. In any case, a known infection should always treated consistently to protect themselves and others. If this is the case, amoebic dysentery is now considered completely curable disease, A century ago, amoebic dysentery was a major health problem in Germany as well.

However, if the amoebic dysentery is not treated, it contributes to the spread of the disease and it can eventually come to dangerous organ involvement, which can end in life-threatening. The two anti-amoebic drugs are well tolerated and promise complete cure if the disease is detected early enough.

Amoebic Dysentery: Prevent

To prevent an amoebic dysentery, you should observe the following rules when traveling in risk areas:

• Peel raw fruits before eating.
• Cook vegetables the best.
• Do not eat raw meat or raw seafood.
• Do not drink water from the water pipe; Also, do not use it to brush your teeth without boiling it.
• Even chlorinated water is not a protection. If you are unsure, always boil the water as a precaution.
• Beware of unsealed water bottles in restaurants, as they are often refilled with tap water.
• Avoid ice cubes or home-made water ice cream as well as sorbet.
• Use different condoms during intercourse and oral sex.

These precautions can help reduce the likelihood of amoebic dysentery. In spite of all precautions, you should suspect that you have one amoebic dysentery you should go to the doctor immediately.