Trichomonas jp


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Trichomonas jp

  2. 2. TRICHOMONAS Genus Trichomonas shows the following important characteristics: I.An anterior tuft of flagellae, II.Undulating membrane, III.An axostyle, IV. Only trophozoite stage. Trichomonas is the simplest of all the protozoan parasites because it has only trophozoite stage. Trichomonas infects the urogenital tract unlike other members of the order Trichomonadida which inhabit the intestinal tract.
  3. 3. HUMAN TRICHOMONADS Trichomonads occurring in humans belong to 3 species : Trichomonas. vaginalis, Trichomonas.tenax & Pentatrichomonas.hominis (Trichomonas.hominis ). These species are highly site specific and typically morphologically similar to each other. Trichomonas.tenax is non pathogenic & inhabits the oral cavity. It is found in the pyorrhoeic dental sockets and around the tartar of the teeth. Pentatrichomonas.hominis (Trichomonas.hominis ) is non-pathogenic & inhabits the Illeocaecal region.
  4. 4. Trichomonas. vaginalis
  5. 5. INTRODUCTION Sexually transmitted infection,known as Trichomoniasis. Discovered in 1836 Donne first observed the flagellate in 1837. 7.4 million cases reported every year 180 million people infected worldwide Resides in genitourinary tract of males and females 50% asymptomatic carriers HABITAT: T.vaginalis trophozoite inhabits the vagina in female, the prostate & seminal vesicles in males and urethra in both sexes.
  6. 6. Trichomonas. vaginalis Facultative anaerobic parasite It produces energy by fermentation of sugars in a structure called Hydrogenosome---A modified mitochondria in which enzyme of oxidative phosphorylation is replaced by enzyme of anaerobic fermentation.
  7. 7. MORPHOLOGY Trichomonas vaginalis belongs to Phylum Metamonada Class: Parabasalia, Order: Trichomonadida Family: Trichomonadidae. Genus : Trichomonas. Trichomonas vaginalis is a flagellated protozoan Trophozoite is the only stage present in the life cycle  Infective stage of the parasite. No cystic stage. It is 7-30 µm long by 5-10µm wide It can survive outside the body at temp as low as 15 0 C for up to 48 hours. Trophozoite is pear shaped & shows “TWITCHING
  8. 8. MORPHOLOGY CONTD There are 4 anterior free flagella, arising from shallow depression, called periflagellar canal in the anterior end of the body. Fifth flagellum curves back along the margin of the undulating membrane & is called Recurrent flagellum. It lies in the shallow groove in the free margin of the undulating membrane. Just beneath the undulating membrane, a rigid filamentous cord called COSTA is present. Costa is believed to support the undulating membrane. It has a median Axostyle which is a hyaline rod like structure that runs throughout the entire length & comes out through the posterior end. Cytoplasm contains a large number of siderophilic granules.
  9. 9. EPIDEMIOLOGY Prevalence :Most common cause of vaginitis world wide It is cosmopolitan in distribution, however prevalence is not uniform because of sanitary and hygiene habits 20-40% in Women 10% in Men. Infected women harboring T.vaginalis in the genital tract---is the chief reservoir. Infected man is the carrier. Main source is vaginal discharge containing T.vaginalis. T.vaginalis infection is seen in all age groups. T.vaginalis infection is seen in both men &women.
  10. 10. EPIDEMIOLOGY High incidence of symptomatic infection occurs in women because of following reasons:1.Natural flora (bacteria) keep the pH of the vagina at 4-4.5 and ordinarily this discourages infections .T. vaginalis can survive at a low pH .Once established it causes a shift towards alkalinity (pH 5-6) which further encourages its growth.2.Presence of zinc & inhibitory substances in the prostatic secretions is harmful to T.vaginalis.Trichomoniasis has been implicated as a cofactor in the transmission of HIV.
  11. 11. TRANSMISSION Sexual intercourse Mutual masturbation Sharing sex toys Mother to child during vaginal delivery
  12. 12. LIFE CYCLE Life cycle of T.vaginalis is simple & it is completed in a single host either male/ Female. In the females, parasite gets the nourishment from 1. vaginal mucosa,2. ingested bacteria 3. RBC. It reproduces by longitudinal binary fission. Division of nucleus Division of neuromuscular apparatus Separation of cytoplasm into 2 daughter trophozoites. Trophozoites are the infective stages On sexual contact, trophozoites are transmitted to male & gets localized in urethra and prostate gland Replicates in the same way.
  13. 13. CAUSES OF VAGINITIS Three main types of vaginitis Bacterial vaginosis About 50% of vaginitis cases - Gardnerella or a mixed anaerobes Trichomoniasis About 20% vaginitis cases- Trichomonas vaginalis Candidiasis About 25% of vaginitis cases C. albicans (80-92%)
  14. 14. PATHOGENESIS & PATHOLOGY It is not an invasive parasite. It remains adherent to the squamous epithelium but not columnar epithelium. VIRULENCE FACTORS: Protein liquids & proteases –help in adherence. Lactic acid and Acetic acid- which lowers the vaginal ph low ph is cytotoxic to vaginal epithelial cells. Enzyme Cysteine proteases CP39-- Responsible for hemolytic activity of the parasite. PATHOLOGY: Intracellular edema and “ chicken like epithelium” is the most characteristic feature.
  15. 15. Biological Mechanism Adhesion proteins on surface of flagella Ligand/Receptor Cytoadherence -11- 23 different CP’s (cysteine proteinases) CP’s play an important role in the pathogenicity of the parasite.
  16. 16. Characteristics of CP39 The characteristics of CP39 are:  It is present in vaginal secretions in patients with trichomoniasis  Its optimal temperature is 37˚C and a pH range of 3.6 to 7.0  Suggested to be involved in tissue damage.  Has broad substrate specificity  Plays a role in parasite survival and immune evasion by degrading hemoglobin and immunoglobulins. Indicative that CP39 plays a role in trichomonal infection
  17. 17. SIGNS & SYMPTOMSIn females there is… urethritis, In males there is… vaginitis&cervicitis.  whitish discharge inflammation of the vaginal although rare canal  pain and burning vulvar itching leading to during urination . edema tenderness and chaffing redness yellow and green, foul smelling discharge painful urination-dysuria pain during sex -dyspareunia punctuate hemorrhages on the cervix known as colpitis macularis or strawberry
  18. 18. COMPLICATIONS In women-PID is the most common & important complication. Pregnant women infected with T.vaginalis infection --- likely to have 1.PROM 2. Premature birth 3. Pre-term/ Low birth weight baby. In men, common complications are prostatitis, Epididymitis, Urethral stricture & Infertility.
  19. 19. LABORATORY DIAGNOSIS I.Direct Detection. II. Culture. III. Antigen detection IV. Nucleic acid detection Techniques.
  20. 20. SPECIMENS In women : Vaginal discharge, Endocervical specimens. Endocervical specimens are not used for wet mount preparations, because of small number of parasites— can collected for culture. In men : 1.urethral discharge 2. prostatic fluid 3.Early morning first voided urine sediment. 4. Urethral swab before voiding urine 5. Semen. Cultures of urethral scrapings/ urine are the most effective method for diagnosis of the condition.
  21. 21. DIRECT DETECTION MICROSCOPY—Saline Wet mount Fixed smears are stained by 1.Acridine orange staining. 2.Papinicolaou staining. 3.Giemsa staining. 4.Leishman staining. 5.Direct Fluorescent Antibody staining.
  22. 22. WET MOUNT Specimen is collected by a swab from lateral &anterior fornices of the vagina. It is mixed with a drop of saline & a cover slip is placed over it. Microscopy shows : T.vaginalis shows jerky & twitching motility. PMN’S and Bacterial flora. Sensitivity of wet mount prep with vaginal secretion is 50-70%. Amies gel agar transport medium can maintain the viability for culture of T.vaginalis.
  23. 23. PERMANENT STAINING 1.Acridine orange staining—Rapid & accurate method. 2.Papinicolaou staining: Sensitivity is same as wet mount 3.Giemsa staining. 4.Leishman staining. 5.Direct Fluorescent Antibody staining: It is more sensitive than wet mount. Rapid method. Disadvantage is the requirement of fluorescent microscope.
  24. 24. CULTURE Culture is the gold standard. It is the most sensitive method (>80%). Specimens are inoculated immediately into appropriate medium such as 1. Modified Diamond’s medium, 2. Trichosel/ Hollander’s medium, 3. Trussel & Johnson medium 4.Trypticase serum medium. Cultures after inoculation are incubated aerobically. In a positive culture, actively motile trophozoites are demonstrated after 48 hrs of incubation at 37C. New Culture systems (In pouch TV) and systems of Empyrean diagnostics is commercially available which allows direct inoculation,Transport, Culture & Microscopy.
  25. 25. ANTIGEN DETECTION 1.ELISA—using Mab specific for a 65 KDa surface polypeptide of T.vaginalis. RAPID TESTS: Latex Agglutination test Immunofluorescent assay Two immunochromatographic capillary flow assays are commercially available-- 1.Osom Trichomonas Rapid test 2.Xenostrip Tv Trichomonas vaginalis test Serologic testing is NOT useful for diagnosis of Trichomoniasis.
  26. 26. MOLECULAR DIAGNOSIS A.DNA PROBES: These use synthetic oligonucleotide probes for detection of Trichomonas vaginalis DNA in vaginal secretions. Affirm VPIII—is a direct DNA probe test & tests for the 3 most common syndromes associated with increased vaginal discharge are: Bacterial vaginosis (Gardenerella vaginalis) Candidiasis (Candida.albicans) Trichomoniasis (T.vaginalis). Sensitivity of Affirm VPIII—is 90% and specificity is 98%. B. Nucleic acid based amplification methods: PCR & Transcription mediated amplification (TMA). These amplification methods are not FDA cleared.
  27. 27. OTHER TESTS DETERMINATION OF VAGINAL PH: Vaginal ph is usually above 4.5 in Trichomoniasis/ Bacterial vaginosis But not in Candidiasis. Vaginal ph is measured by Nitrazine paper method. WHIFF TEST/ AMINE ODOR TEST: This test is positive in Trichomoniasis/ Bacterial vaginosis In this test, vaginal swab is collected from the patient and is mixed with 10% KOH for the presence of polyamines. In the presence of Trichomoniasis, a fishy odour is released due to production of amines.
  28. 28. TREATMENT . Treatment : Single dose of Metronidazole 2 gm once, or Metronidazole PO 500 mg TDS for 7 days For recurrent Trichomoniasis :Metronidazole x 7 days and Repeat, if still positive then give Metronidazole 2 gm BD x5d Tinidazole or Miconazole used if resistant Metronidazole is contraindicated in the first trimester Intravaginal Clotrimazole 100mg vaginal suppository QID x7d Reinfection can happen almost immediately Treat the male sexual partner Tinidazole is an alternate drug
  29. 29. PREVENTION 1.Personal hygiene 2. Barrier precautions 3.Avoidance of sexual contact with infected partners. 4.Detection & Treatment of cases either males/females. NO VACCINE IS AVAILABLE.