Rapid Diagnosis of Intestinal Parasitic Protozoa, with a Focus onEntamoeba histolytica

Abstract

Entamoeba histolyticais an invasive intestinal pathogenic parasitic protozoan that causes amebiasis. It must be distinguished fromEntamoeba disparandE. moshkovskii, nonpathogenic commensal parasites of the human gut lumen that are morphologically identical toE. histolytica. Detection of specificE. histolyticaantigens in stools is a fast, sensitive technique that should be considered as the method of choice. Stool real-time PCR is a highly sensitive and specific technique but its high cost make it unsuitable for use in endemic areas where there are economic constraints. Serology is an important component of the diagnosis of intestinal and especially extraintestinal amebiasis as it is a sensitive test that complements the detection of the parasite antigens or DNA. Circulating Gal/GalNac lectin antigens can be detected in the serum of patients with untreated amoebic liver abscess. On the horizon are multiplex real-time PCR assays which permit the identification of multiple enteropathogens with high sensitivity and specificity.