Entamoeba gingivalis , a commensal of the oral cavity

pathogenic or non-paathogenic, entamoeba gingivalis has been isolated from the oral cavity and from women using IUDs though deemed a commensal in immunocompromised AIDS patients causes much oral damage

1. Entamoeba gingivalis Dental class 07/06/22

2. Introduction Global in distribution Entamoeba gingivalis is a protozoan endoparasite that colonizes the gingival tissue First amoeba described in humans E. gingivalis was first observed by Gros in 1849 in the tartar of teeth Description was given by Von Prowazak in 1904.

3. Introduction… The eukaryotic protozoan  Entamoeba gingivalis  colonizes the healthy oral cavity with a prevalence of 15% Inflamed periodontal pockets of periodontitis patients are infected with a frequency of 70% to 80%

4. Introduction…. E. gingivalis  has strong potential to cause and promote inflammation and to actively invade the oral mucosa, where it may contribute to profound tissue destruction.  Trophozoites of the species may be recovered from the mouths of a significant percentage of patients with periodontal diseases Its direct pathogenic role is increasingly being established by recent research

5. E. gingivalis a ids other microorganisms to invade the oral mucosa, where they may further enter into the circulation with potential damaging effects on the vasculature. Inhabit the mouth The cystic stage being apparently absent. Introduction ….

6. Introduction…. Frequency of isolation appears to increase with age Isoenzyme pattern R iboprinting PCR may be used to distinguish from other species

7. Introduction…. Most patients with severe and recurrent periodontitis (gum disease) showed an increased presence of the amoeba  Entamoeba gingivalis  inside their oral cavities. F ound in bronchial washings and in the vaginal and cervical smears from women using intrauterine devices

8. TRANSMISSION: Direct from one person to another by kissing, by droplet spray, or by sharing eating utensils.

9. Morphology Entamoeba gingivalis resembles Entamoeba histolytica , and diagnosis requires great attention. E. gingivalis is actively motile with multiple pseudopodia. Does not have resistant forms (cysts) Trophozoites , vary in size from 10–20 µm in diameter and are transparent Nucleus is round with central karyosome lined by coarse chromatin granules Chromatin is concentrated on the nuclear membrane’s inner surface

10. Morphology…. Cytoplasm can be differentiated into clear ectoplasm and granular endoplasm, the cytoplasm contains food vacuoles Molecular studies indicate the ability to encyst has been lost over time.

11. Morphology…. Food vacuoles consists of digested leukocytes and epithelial cell, bacteria are seen at times Red blood cells are seen very rarely

12. Morphology

13. Habitat I nhabits the area around the teeth and gums, including the spaces between teeth, and especially in teeth cavities, dental tartar, necrotic mucosa of cells and the gingival fringes of the gums and sometimes in the crypts of tonsils. The organisms often are abundant in cases of gum or tonsil disease, but no evidence that they cause these conditions.

14. Habitat They even seem to fare well on dentures if the devices are not kept clean. Entamoeba gingivalis also infects other primates, dogs, and cats. Up to 95% of persons with unhygienic mouths may be infected, and up to 50% of persons with healthy mouths may harbor this ameba .

15. Habitat According to some studies, this amoeba is also an important agent in the induction of periodontitis E. gingivalis is recognized as causing gum itch, fatigue halitosis, severe headaches, sore palate and periodontal tissue damage

16. Studies and Research Infection rates of this amoeba in patients with periodontitis are higher than those of healthy control groups According to some studies, E. gingivalis produces progressive, periodontal disease among immunocompromised patients . A Swedish study showed its association with human immunodeficiency virus type 1 (HIV-1)

17. Pathogenesis Important cause of periodontal disease, generating gum itch, sore palate, halitosis, fatigue, severe headaches, and periodontal tissue damage

18. Life Cycle Trophozoites live in the oral cavity of humans, residing in the gingival pockets near the base of the teeth and feed on bacteria and other debris. Trophozoites are transmitted person-to-person orally by kissing or fomites (such as eating utensils) . The trophozoite stage of E. gingivalis is morphologically similar to that of E. histolytica. The two should be differentiated, as both can be coughed up in sputum specimens

19. Clinical Symptoms Infections of E. gingivalis occurring in the mouth and in the genital tract typically produce no symptoms. Nonpathogenic E. gingivalis trophozoites are frequently recovered in patients suffering from pyorrhea alveolaris. It appears that the trophozoites thrive under disease conditions but do not produce symptoms of their own

20. Laboratory Diagnosis Direct microscopy of mouth scrapings, particularly from the gingival area or on preculture in specialized parasitological media

21. Treatment Treatment of E. gingivalis is typically not indicated because the organism is generally considered a nonpathogen.

22. Excerpts E. gingivalis, potential to turn into opportunistic pathogens Oral protozoa are rarely found in children, while the frequency of infection increases with age Infections with Entamoeba gingivalis should be regarded as an factor associated with the pathological changes occurring in patients with periodontal diseases.

23. References Entamoeba gingivalis  Exerts Severe Pathogenic Effects on the Oral Mucosa X. Bao , 1   J. Weiner, 3rd , 2   O. Meckes , 3   H. Dommisch , 1  and  A.S. Schaefer 1 J Dent Res.  2021 Jul; 100(7): 771–776. THE OCCURRENCE OF ENTAMOEBA GINGIVALIS AMONG PATIENTS WITH PERIODONTAL DISEASE Joanna Luszczak1*, Michal Bartosik1, Jolanta Rzymowska1, Agnieszka Sochaczewska-Dolecka2, Ewa Tomaszek3, Joanna Wysokinska-Miszczuk3, Anna Bogucka-Kocka1

24. References Textbook of parasitology by paniker Textbook of parasitology by chatterjee

25. Assignment T rogocytosis

26. Further discussion Cysts of E. gingivalis were reported in the literature at the beginning of the twentieth century ( Chiavaro , 1914 ; Smith and Barrett, 1915b ; Craig, 1916 ). However, it is now commonly accepted that E. gingivalis does not produce cysts, Nevertheless , the parasite E. gingivalis is essentially observed in periodontal pockets, suggesting that low oxygen levels are important for the survival of trophozoites , as in the case of E. histolytica and E. dispar [reviewed in Olivos -Garcia et al. (2016) ].

27. Further discussion Direct transmission of trophozoites to a new host would imply that they are resistant to oxygen, which raises questions about how E. gingivalis is transmitted in nature, and what ecological niche serves as a reservoir for this microorganism. Unfortunately, the complete life cycle of E. gingivalis is still missing and not addressed yet, hampering efficient prophylaxis.

28. Thank you!