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Entamoeba moshkovskii is associated with diarrhea in infants and

The 3 rd International Conference, Sept 1, 2012 at ICDDR, B. Entamoeba moshkovskii is associated with diarrhea in infants and causes diarrhea and colitis in mice. Shinjiro Hamano Department of Parasitology, Institute of Tropical Medicine, Nagasaki University, Japan. 約 1km 2.

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Entamoeba moshkovskii is associated with diarrhea in infants and

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  1. The 3rd International Conference, Sept 1, 2012 at ICDDR, B. Entamoeba moshkovskii is associated with diarrhea in infants and causes diarrhea and colitis in mice Shinjiro Hamano Department of Parasitology, Institute of Tropical Medicine, Nagasaki University, Japan

  2. 約1km2 • Bihari ethnic origin • Settledthere after 1971 • Poor sanitary and hygienicconditions • Use pit latrines • The mean monthly familyincome was around $65 U.S ICDDR, B.: Mr. Kabir, Ms. Sobuz , Dr. Mondal, Dr. HaqueUniversity of Virginia: Dr. Taniuchi, Dr. Ali Prof. Houpt, Prof. Petri 1

  3. Life cycle of Entamoeba histolytica(an extra-cellular protozoan parasite) 10-60 mm 5-20 mm Haque R et al. N Engl J Med 2003;348:1565-1573

  4. Backgrounds E. histolytica is pathogenic, although it was recently shown that all of genotypes of E. histolytica are not equally capable of causing disease. E. dispar is non-pathogenic. Then, the question is if E. moshkovskii is……?

  5. Entamoeba moshkovskii • was first identified in 1941 and was thought to be a free-living common protozoan species. • The first human isolate was obtained from a resident of Laredo, Texas, who suffered from diarrhea, weight loss, and epigastric pain in 1961. • This isolate was named E. histolytica Laredo and shared biological features with E. moshkovskii. • E. histolytica Laredo is identical with E. moshkovskii. Thus, E. moshkovkii is able to at least parasitize in human. Development of molecular biological method Development of PCR method

  6. An unrooted phylogenetic reconstruction among Entamoeba species. E. dispar Within the group of four nucleated-cyst-producing species, Entamoeba moshkovskii joins Entamoeba histolytica and Entamoeba dispar in a well-supported clade. E. histolytica E. moshkovskii E. insolita 4 nuclei per cyst E. sp. NIH:1091:1 E. hartmanni E. ranarum E. invadens E. terrapinae non-cyst former E. gingivalis E. chattoni 1 nucleus per cyst E. polecki E. coli strain IH:96/135 8 nuclei per cyst E. coli strain HU-1:CDC 16S-like rDNA Silberman J.D. et al. Mol. Biol. Evol. 16(12):1740–1751. 1999

  7. E. moshkovskii • is morphologically similar to E. histolytica and E. dispar. • is microscopically indistinguishable from them. • is biochemically and genetically different from them. • High incidence of E. moshkovskii has been reported in developing countries by PCR in human fecal samples. However, it remains unclear whether E. moshkovskii is pathogenic or non-pathogenic.

  8. In order to clarify the pathogenicity of E. moshkovskii, at first, we tested the ability of E. moshkovskii to cause colitis and diarrhea in a murine model system.

  9. Summary In the murine model of intestinal amebiasis, E. moshkovskii caused diarrhea, weight loss and colitis. In this way, E. moshkovskii shared the ability to cause disease with E. histolytica, but not with non-pathogenic E. dispar. Shimokawa, C., etal. J. Infect. Dis. 2012; 206: 744-51

  10. Then, the association between diarrheal episodes and infection with each Entamoeba spp. was examined in children in Mirpur, Dhaka, Bangladesh. These studies were part of a prospective cohort study on diarrheal diseases in newborns, which prospectively followed for diarrheal illness by every other day home visits.

  11. 約1km2 • Bihari ethnic origin • Settledthere after 1971 • Poor sanitary and hygienicconditions • Use pit latrines • The mean monthly familyincome was around $65 U.S ICDDR, B.: Mr. Kabir, Ms. Sobuz , Dr. Mondal, Dr. HaqueUniversity of Virginia: Dr. Taniuchi, Dr. Ali Prof. Houpt, Prof. Petri 10

  12. Field research assistants (FRAs) visited each study house every other day and collected information related to child morbidity, especially for diarrheal illness. FRAs collected non-diarrheal monthly stool specimens as well as diarrheal stool specimens from the home or in the study field clinic. All stool specimens were transported from the field to the clinic, then to ICDDR, B. using a cold box.

  13. Diarrhea was defined as having three or more unformed or abnormal stools (as per the mother’s perception) in a 24 hour period. • A diarrheal episode was defined as being separated from another episode by at least three diarrhea-free days. A total of 1426 diarrheal episodes were recorded during the first 12 months of life in 385 children.

  14. Ali, I.K. et al.: Entamoeba moshkovskii infections in children, Bangladesh. Emerg Infect Dis. 2003; 9(5): 580-584. Among 109 stool specimens that were positive for Entamoeba spp. from Bangladeshi preschool children 39 were positive for E. dispar (35.8%), 23 were positive for E. moshkovskii (21.1%), 17 were positive for E. histolytica (15.6%).

  15. The frequency of E. moshkovskiiin diarrheal stools is comparable to that of E. histolytica in Mirpur children. The 1426 episodes of diarrhea were observed in  385  children during the first 12 months of life. E. histolytica (4.63%) E. moshkovskii (2.95%) 2 2 64 40 0 0 0 5 E. dispar (0.35%)

  16. Both diarrheal severity score and duration are comparable between episodes positive for E. histolytica andE. moshkovskii. Severity score mean ±SE Duration in daysmean ± SE Pathogen E. histolytica 4.89 ± 0.22 4.44 ± 0.44 * * E. moshkovskii 4.71 ± 0.24 4.74 ± 0.49 Others 4.84 ± 0.05 4.84 ±0.10 *No significant difference between means. The  mean age of the onset of diarrheal episodes positive for E.h., E.m. and E.d. are observed at 235, 277 and 510 days old, respectively.

  17. As there are many microbes that can potentially induce diarrhea, the presence of other diarrheagenic microbes was examined in the 42 diarrheal samples that were associated with E. moshkovskii. • standard bacterial culture • fecal antigen detection • multiplex PCR combined with probe-based • detection with Luminex beads

  18. Many enteropathogens were detected in 42 of Em+ diarrheal stools

  19. The diarrheal episodes associated withE. moshkovskii were commonly co-infected. The application of these state-of-the-art diagnostic techniques in this cohort has on average identified a minimum of two different enteropathogens in every diarrheal stool sample (Houpt E and Taniuchi M personal communication).

  20. The new acquisition of E. moshkovskii infection was associated with diarrhea. Prevalence of E. moshkovskii asymptomatic infectionpreceding E. moshkovskii-associated diarrhea in 42 children

  21. Conclusions E. moshkovskii caused diarrhea, colitis and weight loss in mice. In children in Bangladesh, the new acquisition of E. moshkovskii infection was associated with diarrhea. These data are consistent with E. moshkovskii causing diarrhea, and indicate that it is important to re-examine its pathogenicity. Shimokawa, C., etal. J. Infect. Dis. 2012; 206: 744-51

  22. Dhaka Acknowledgments to Rashidul Bill Shihab Dinesh FRAs Mamun Nagasaki Charlottesville, Virginia Eric Chikako Masataka Seiki (Keio) Mami Ibne

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