Abstract
Entamoeba histolytica was first identified as a human pathogen in the 19th century,1 and it was subsequently given its species name because of its ability to lyse human tissue. Since that time, the approach to this important pathogen has been based primarily on its morphologic characteristics. Although Diamond and his colleagues have developed an in vitro culture system,2 it is unavailable in most clinical microbiology laboratories. Thus, the diagnosis of intestinal amebic infection is typically based on stool examination alone. However, this method is insensitive because the parasite cannot replicate under these conditions, and it is subject to error because . . .