amebiasis

Amoebiasis, or amoebic dysentery, is an infection of the intestines caused by a parasitic amoeba Entamoeba histolytica. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include lethargy, loss of weight, colonic ulcerations, abdominal pain, diarrhea, or bloody diarrhea. Complications can include inflammation and ulceration of the colon with tissue death or perforation, which may result in peritonitis. Anemia may develop if there is prolonged gastric bleeding.

Cysts of Entamoeba can survive for up to a month in soil or for up to 45 minutes under fingernails. Invasion of the intestinal lining may result in bloody diarrhea. If the parasite reaches the bloodstream it can spread through the body, most frequently ending up in the liver where it can cause amoebic liver abscesses. Liver abscesses can occur without previous diarrhea. Diagnosis is made by stool examination using microscopy, but it can be difficult to distinguish E. histolytica from other harmless entamoeba species. An increased white blood cell count may be present in severe cases. The most accurate test is finding specific antibodies in the blood, though the antibody test may remain positive following treatment. Bacterial colitis can result in similar symptoms.