[Recent progress in the diagnosis of intestinal amebiasis. Contribution of molecular biology]

Only 10% of Entamoeba histolytica strains have been reported to have a pathogenic capacity. Theoretically and under certain conditions, confirming this estimation should limit the number and the cost of the treatments administered to the four hundred million asymptomatic carriers in the world. Several new routine tests which allow more accurate and easier diagnosis of intestinal amoebiasis and in particular the differential diagnosis between the pathogenic and nonpathogenic strains are or soon will be available. The practical interest of some of these new tests is limited by the problem of assessing parameters such as the stability in vivo and the nonpathogenic features of the nonpathogenic strains, the frequency of the association between pathogenic and nonpathogenic strains, the prevalence of pathogenic strains compared with the nonpathogenic strains, and the kinetics of the elimination of the parasitic forms. Even if these tests are assumed to be efficient, they cannot be regarded as absolutely reliable because of the complexity of the clinical disease.