TRYPANOSOMIASIS microbiology lab investigation and investigation.pptx

TRYPANOSOMIASIS microbiology lab investigation and investigation.pptx

1. TRYPANOSOMIASIS LAB DIAGNOSIS & TREATMENT ~ DHAYANITHISRIRAM A M DHAYALAN S

2. AFRICAN TRYPANOSOMES AFRICAN SLEEPING SICKNESS caused by Trypanosoma brucei Transmitted by Tsetse fly

3. Diagnosis involves 3 steps SCREENING for potential infection using serological tests (only available for  T. b. gambiense ) and clinical examination CONFIRMATION by observing microscopically the parasite in body fluids STAGING THE DISEASE PROGRESSION via clinical examination and analysis of cerebrospinal fluid obtained by lumbar puncture , if needed DIAGNOSIS

4. In the Rhodesian type , lumbar puncture is indicated because of early CNS invasion. Serologic tests, such as indirect immunofluorescence direct card agglutination & indirect hemagglutination - are used successfully for diagnosis. In the early stages of the disease , the parasites can be demonstrated in lymph nodes and blood ; later , they appear in the cerebrospinal fluid .

5. LAB DIAGNOSIS Examination of Blood Other Diagnostic modalities Examination of CSF Examination of Aspirates from enlarged Lymph glands

6. Lateral flow immunochromatographic devices can detect low concentrations of antibodies targeting antigens in biological fluids rapid diagnostic tests (RDTs) that detect anti-trypanosome antibodies in human finger-prick blood samples. Antibody Detection  CATT (Card-Agglutination Trypanosomiasis Test) . CATT is a serological test, useful for initial population screening to identify suspected cases.  CTC (Capillary Tube Centrifugation) .  Ag & Ab Detection in CSF & SERUM Molecular Method

7. EXAMINATION OF BLOOD Thick & Thin Peripheral Blood Smear Detecting characteristic Trypomastigote forms of T.brucei Trypomastigote forms

8. Undulating membrane Nucleus Kinatoplast Flagella 14-33  μ m

9. EXAMINATION OF CSF TO CONFIRM THE CNS INVASION Detection of trypomastigotes i n CSF WBC Count of >20 cells/ μ L of CSF with parasite detected in blood or lymph node aspirate Staging diagnosis - lumbar puncture Normal WBC in CSF 5 per cubic mm

10. OTHER DIAGNOSTIC MODALITIES Culture (Blood) onto NNN Media ( Novy macNeal Nicolle medium) Animal inoculation(MICE) blood incubation infectivity test Detect epimastigotes Animal inoculation

11. Ag & Ab Detection in CSF & SERUM Molecular Method Ab based tools Latex/ Tbg HAT sero Ab HAT Sero strip Ab based tools Latex/ IgM Immune factors Protein Genome based tools PCR LAMP DISEASE TRANSMISSION DISEASE PROGRESSION

12. screening confirmation staging

13. Trypanosomes have evolved to prevent the adaptive immune response of the host by maintaining a variant surface glycoprotein (VSG) coat which expresses one of ~1500 surface glycoprotein genes. This ensures that once the host mounts an effective complementary immune response, the infection will persist into the next generation until the host mounts another complementary response. This variable expressive pattern is the main reason patients with chronic trypanosomiasis show cyclical bouts of infection followed by a period of relative latency. By the time the host’s immune system identifies and synthesizes antibodies to combat certain trypanosomes, a percentage of the total trypanosome population has evaded detection and continued the infection . TRYPOMASTIGOTE FORMS OF T.BRUCEI Polymorphic trypanosomes

14. Treatment should be started asap and is based on the infected person's symptoms and laboratory tests results. hospitalized for treatment & require periodic follow-up exams for 2 years. Treatment

15. Current standard treatment for first stage PENTAMIDINE (for T.b . gambiense ) - IV SURAMIN (for T.b . rhodesiense ) current standard treatment for second stage EFLONITHINE (for T.b . gambiense ) MELARSOPROL (for T.b . rhodesiense ) – IV

16. There is no vaccine or drug to prevent African trypanosomiasis . When traveling in areas where the disease occurs, take these precautions against bites from tsetse flies and other insects. Prevention

17. THANKYOU…