[Investigation on Entamoeba histolytica infection in diarrhea patients from general hospitals in Shanghai City]

To understand the status of Entamoeba histolytica infection in diarrhea patients in general hospitals, so as to provide the evidences for the prevention and control of the disease.The diarrhea patients in intestinal disease clinics of 3 general hospitals in Shanghai City were chosen as the investigation objectives, and their fecal and blood samples were collected, and then were detected by the normal saline direct smear method and iodine solution staining, immunochromatographic method and ELISA respectively to understand the infection status of E. histolytica, and the characteristics of the infected persons were analyzed. RESULTS Totally 1 015 fecal samples were detected, and among which 36 positive ones were detected by parasitological examinations, with a general positive rate of 3.55%. There were no statistically significant differences among the positive rates of patients from the three hospitals (P0.05), nor between or among those of the patients with different sexes, ages, occupations and education levels (all P0.05). The positive rate of E. histolytica in bloody purulent stools was higher than those in loose stools and watery stools (both P0.01). The peak period of infection was from July to September. Among the 36 infected people detected by parasitological examination, 88.90% of them complained about abdominal pain, and the red blood cells and leucocyte cells were found in the stool samples of 75.00% and 22.23% of the cases, respectively. The positive rates of E. histolytica were 8.18% (83/1 015) and 7.12% (48/675) respectively when detected by the immunochromatographic method and ELISA.Summer and autumn are the high risk seasons for E. histolytica infection, and the surveillance should be strengthened in this period. The positive rate of E. histolytica in samples of bloody purulent stools is high, and the combined application of several detection methods can increase the detection rate.