Contribution to the problem of the so-called nonpathogenic amoebae in the intestine of man.

Among 10,418 patients of a Prague hospital, a plain infection with intestinal parasitic protozoans was identified in 1,319 persons (12.7%). Of these, 3.5% were infested with Giardia intestinalis, 0.3% with Entamoeba histolytica forma minuta, 5.7% with Endolimax nana. We evaluated the frequency of findings of protozoans in various clinical diagnoses. A statistically significant increase in frequency was recorded for E. nana in diagnoses of eosinophilia, giardiasis, amoebiasis and helminthiasis. A slight increase above the average was found for Entamoeba coli in diagnoses of giardiasis and helminthiasis. Most cases of infection with Entamoeba histolytica were associated with a stay abroad. No increase in the frequency of these protozoans was recorded for patients with diarrhea. An analysis of the results indicated that a nonpathogenic amoeba might participate in the origin of intestinal disorders in man.