Since antibodies may persist for years after clinical cure, a positive serological result may not necessarily indicate an active infection. A negative serological result, however, can be equally important in excluding suspected tissue invasion by E. histolytica.Stool antigen detection tests have helped to overcome some of the limitations of stool microscopy. Antigen detection tests are easy to use, but they have variable sensitivity and specificity, especially in low-endemic areas.Polymerase chain reaction (PCR) is considered the gold standard for diagnosis but remains underutilized. Prevention
To help prevent the spread of amoebiasis around the home :
Wash hands thoroughly with soap and hot running water for at least 10 seconds after using the toilet or changing a babys diaper, and before handling food. Clean bathrooms and toilets often; pay particular attention to toilet seats and taps. Avoid sharing towels or face washers.To help prevent infection:
Avoid raw vegetables when in endemic areas, as they may have been fertilized using human feces. Boil water or treat with iodine tablets. Avoid eating street foods especially in public places where others are sharing sauces in one containerGood sanitary practice, as well as responsible sewage disposal or treatment, are necessary for the prevention of E. histolytica infection on an endemic level. E.histolytica cysts are usually resistant to chlorination, therefore sedimentation and filtration of water supplies are necessary to reduce the incidence of infection.E. histolytica cysts may be recovered from contaminated food by methods similar to those used for recovering Giardia lamblia cysts from feces.
Cutaneous amoebiasis can also occur in skin around sites of colostomy wound, perianal region, region overlying visceral lesion and at the site of drainage of liver abscess.Urogenital tract amoebiasis derived from intestinal lesion can cause amoebic vulvovaginitis (Mays disease), rectovesicle fistula and rectovaginal fistula.Entamoeba histolytica infection is associated with malnutrition and stunting of growth in children. Epidemiology
Amoebiasis caused about 55,000 deaths worldwide in 2010, down from 68,000 in 1990. In older textbooks it is often stated that 10% of the worlds population is infected with Entamoeba histolytica. Nevertheless, this means that there are up to 50 million true E. histolytica infections and approximately seventy thousand die each year, mostly from liver abscesses or other complications. Although usually considered a tropical parasite, the first case reported (in 1875) was actually in St Petersburg in Russia, near the Arctic Circle. Infection is more common in warmer areas, but this is because of both poorer hygiene and the parasitic cysts surviving longer in warm moist conditions. History
Amoebiasis was first described by Fedor A. Lösch in 1875, in northern Russia. The most dramatic incident in the US was the Chicago Worlds Fair outbreak in 1933, caused by contaminated drinking water. There were more than a thousand cases, with 98 deaths. It has been known since 1897 that at least one non-disease-causing species of Entamoeba existed (Entamoeba coli), but it was first formally recognized by the WHO in 1997 that E. histolytica was two species, despite this having first been proposed in 1925.