Molecular differentiation of Entamoeba histolytica and Entamoeba dispar from stool and culture samples obtained from Polish citizens infected in tropics and in Poland

The examinations were carried out on stool and serum samples obtained from 38 Polish citizens infected with E. histolytica sensu late. Prevalence of infection (according microscopic examinations) was 0.63% in the Polish who come back from abroad and about 0,19% in persons who did not leave our country. The investigations were performed with isoenzyme analysis and polymerase chain reaction with the use of specific (Psp, NPsp) and (p11+p12, p13+p14) primers. Serodiagnostic examinations were done with antigen produced from E. histolytica HK-9 axenic strain. The examinations revealed that in 31 cases the amoebae belonged to nonpathogenic E. dispar, in 4 to pathogenic E. histolytica, among this one indigenous case; and in two cases were mixed infections. In one case we neither got DNA amplification products nor cultured amoebae. However, from 25 persons we obtained amoebae cultures helping in identification the amoebae zymodemes. The prevailing zymodeme was nonpathogenic zymodeme I. The PCR results were in agreement with isoenzymatic and serodiagnostic examinations.