Amoebiasis - Symptoms

In countries where amebiasis (E. histolytica) is widespread, 90% of infected individuals have noninvasive amebiasis, that is, they do not have any symptoms of amebiasis, thus they are asymptomatic carriers of luminal forms of amoebas, and only 10% of infected individuals develop invasive amebiasis.

There are two main forms of invasive amoebiasis: intestinal and extraintestinal.

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Symptoms of intestinal amebiasis

When lesions are localized in the rectosigmoid region of the colon, the symptoms of amebiasis may correspond to a dysentery-like syndrome with tenesmus and occasionally with an admixture of mucus, blood and pus in the stool. When lesions are localized in the cecum, constipation with pain in the right iliac region and symptoms characteristic of the clinical picture of chronic appendicitis are noted (in some cases, appendicitis actually develops). In the ileum, amebic lesions are relatively rare.

Clinical variants of intestinal amoebiasis

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Acute intestinal amebiasis (acute amoebic colitis)

Acute intestinal amebiasis (acute amoebic colitis) often manifests itself only as diarrhea. Less common is amoebic dysentery syndrome - symptoms of amebiasis such as: acute onset, cramping abdominal pain, tenesmus, loose stools with blood and mucus. High fever and other manifestations of intoxication syndrome are rare. However, young children usually experience fever, vomiting, and dehydration.

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Fulminant colitis

Severe necrotizing form of acute intestinal amebiasis - fulminant colitis. This form is characterized by toxic syndrome, total and deep damage to the intestinal mucosa, bleeding, perforation, peritonitis. It is most often detected in pregnant and postpartum women, and can develop after the administration of glucocorticoids. Mortality is extremely high. Acute intestinal amebiasis in endemic areas is often caused by a combination with shigellosis, malaria, typhoid fever, which are also widespread and have a mutually aggravating effect on the severity of the infectious process. For example, typhoid fever increases the risk of developing both intestinal and extraintestinal lesions by 5-6 times.

Protracted intestinal (primary chronic) amebiasis

Characteristic symptoms include impaired intestinal motor function, loose stool, constipation (50% of cases) or unstable stool, pain in the lower abdomen, nausea, weakness, poor appetite. Over time, signs of hypochromic anemia appear, trophic disorders, hypovitaminosis, and intestinal dysbiosis develop. Without antiparasitic treatment, the disease progresses, complications and cachexia develop.

Symptoms of extraintestinal amebiasis

Pathological changes in extraintestinal amoebiasis can develop in almost all organs, but they are most often observed in the liver. Amoebic liver abscess is recorded 5-50 times less frequently than amoebic colitis.

Liver abscess

In patients with amoebic liver abscess, indications of previously suffered intestinal amoebiasis are detected only in 30-40% of cases, and amoebas are found in feces in no more than 20% of patients. Amoebic liver abscessIt develops more often in adults than in children, and more often in males than in females. Single or multiple abscesses form mainly in the right lobe of the liver in close proximity to the diaphragm or in the lower parts of the organ.

The following symptoms are typical for amoebic liver abscess: fever with chills and profuse sweating at night; enlargement and pain in the liver area, moderate leukocytosis. With large abscesses, jaundice may develop, which is considered a poor prognostic sign. A high position of the diaphragm dome, limited mobility are detected; atelectasis in the lower parts of the lungs may develop. Relatively often (10-20%), a long latent or atypical course of abscess is noted (for example, only fever, pseudocholecystitis, jaundice) with a possible subsequent breakthrough, which can cause peritonitis or empyema of the pleura.

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Pleuropulmonary amoebiasis

Pleuropulmonary amoebiasisoften occurs as a result of a liver abscess breaking through the diaphragm into the lungs, less often due to the spread of amoebas through the blood vessels. It manifests itself as pleural empyema, lung abscesses, and hepatobronchial fistula. Characteristic symptoms include chest pain, cough, shortness of breath, pus and blood in sputum, chills, fever, leukocytosis in the peripheral blood, and elevated ESR.

As a result of a liver abscess rupturing from the left lobe through the diaphragm into the pericardium, amoebic pericarditis may develop, which can lead to cardiac tamponade and death.

Brain abscess

Brain abscessoccurs rarely, usually has a hematogenous origin. The lesions can be single or multiple; they can be located in any part of the brain (usually in the left hemisphere). The symptoms of this form of amebiasis are usually acute, lightning-fast, and fatal.

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Amebic skin lesion

Amebic skin lesiondevelops more often in weakened and exhausted patients. Ulcers are usually localized in the perianal area, at the site of abscess rupture in the fistula area, in homosexuals they are noted in the genital area.

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Complications of amoebiasis

The main complications of intestinal amebiasis are intestinal perforation (usually in the cecum, less often in the rectosigmoid region), which may result in peritonitis or abdominal abscess; amoebic appendicitis; amoebic intestinal strictures (usually single, located in the cecum or sigmoid colon): intestinal bleeding, formation of ameboma. The most serious complication of extraintestinal amebiasis is abscess rupture into surrounding organs.

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