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Spirochetes and Neisseria (Gram negative) Lecture 36

Spirochetes and Neisseria (Gram negative) Lecture 36. Faculty: Dr. Alvin Fox. Spirochete Axial filament Treponema pallidum Syphilis Chancre Primary lesion Darkfield microscopy Secondary Lesion Tertiary Lesion Anti-cardiolipin antibodies Anti-treponemal antibodies.

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Spirochetes and Neisseria (Gram negative) Lecture 36

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  1. SpirochetesandNeisseria(Gram negative)Lecture 36 Faculty: Dr. Alvin Fox

  2. Spirochete Axial filament Treponema pallidum Syphilis Chancre Primary lesion Darkfield microscopy Secondary Lesion Tertiary Lesion Anti-cardiolipin antibodies Anti-treponemal antibodies Borrelia burgdorferi Lyme disease Relapsing fever (other borrelia) Leptospira (leptospirosis) Neisseria Thayer Martin agar Oxidase test N. gonorrhoeae Gonorrhea N. meningitidis Meningitis Key Words

  3. SPIROCHETES Treponema, Borrelia and Leptospira

  4. Spirochetes • Gram negative • long, thin, helical, motile • axial filaments • locomotion • between peptidoglycan layer/outer membrane • runs parallel

  5. www.orl.cz/choroby/ustni/jazyk/zanet/1 Histology: Treponema pallidum - testis infected rabbit

  6. Treponema pallidum • transmission • genital/genital • in utero or during birth

  7. Syphilis • chronic • slowly progressive

  8. Secondary (2-10 weeks later) • - systemic spread • - flu-like symptoms • - skin, particularly • - many organisms • - Highly infectious

  9. Tertiary • several years later • rare • skin • central nervous system • delayed hypersensitivity • few organisms • control by immune response

  10. Microbiological diagnosis • not culturable • dark field microscopy • actively motile organisms • brightly lit against dark backdrop • light shines at an angle • reflected from thin organisms • enters objective • conventional light microsrcopy • light shines through • NOT visualized

  11. fluorescence microscopy • antibody staining

  12. Secondary and Tertiary Syphilis- serology • screening method • antibodies to cardiolipin • specific diagnosis • antibodies to treponemal antigen

  13. Autoimminty • cardiolipin • self antigen

  14. no vaccine • antibiotics (e.g. penicillin) • effective

  15. Other treponemal diseases • bejel, yaws and pinta • extremely rare in US

  16. Borrelia burgdorferi and Lyme disease

  17. Ixodes scapularis, tick vector for Lyme disease. Also known as Ixodes dammini. CDC

  18. Lyme disease - symptoms • bacteremia • acute • arthritis • cardiac • neurologic • chronic • weeks, months later

  19. Therapy • early antibiotic therapy • curable • penicillin • tetracycline • late antibiotic administration • ineffective

  20. Diagnosis • serum antibodies to B. burgdorferi. • laboratory strains • grow extremely slowly • tissue culture media • not bacteriological media • patient body fluids/tissue sample • almost never growth

  21. A physicians dilemma • acute • responds to antibiotic • antibodies not detectable • late diagnosis • not curable • antibodies detectable

  22. Lyme Disease -etiology • reactive arthritis similar to • Reiter's syndrome • rheumatic fever • resembles rheumatoid arthritis

  23. Relapsing fever • <100/ per year in US • transmission • tick-B. hermsii • rodent, primary host • lice-B. recurrentis • human, primary host

  24. “Relapsing” fever • immune response develops • disease relapses • new antigens expressed • no immunity • disease reappears

  25. Diagnosis • no culture • no serological test • detected - blood smear

  26. Leptospirosis

  27. Leptospirosis • <100 cases per year in US • symptoms • flu-like • severe systemic disease • kidney • brain • eye

  28. Transmission • infected urine • rodents • farm animals • water • through broken skin.

  29. Laboratory Diagnosis • serology • most readily culturable of spirochetes • culture still extremely difficult

  30. NEISSERIA Neisseria gonorrhoeae

  31. Neisseria • Gram negative • diplococci (pairs of cocci) • oxidase positive • culture • Thayer Martin. • selective • chocolate agar • heated blood (brown)

  32. N. gonorrhoeae the “Gonococcus" • found only in man • gonorrhea • second most common venereal disease

  33. Smear • polymorphonuclear cell • Gram negative cocci • many in cells

  34. Dissemination -gonococci • gonoccocal arthritis • “septic” arthritis • dermatitis

  35. Antibiotic therapy • βlactamase-resistant cephalosporin • e.g. ceftriaxone • resistant strains • common • produceβ lactamases • destroy penicillin

  36. Pathogensis • adhesion to genital epithelium • outer membrane • pili • Antigenicity • highly variable among strains • no vaccine • IgA protease • also N. meningitidis

  37. N. gonorrhoeae • Tissue injury • lipopolysaccharide • peptidoglycan

  38. N. meningitidis(the “Meningococcus")

  39. N. meningitidis • resides in man only • usually sporadic cases • mostly young children • outbreaks • adults • crowded conditions • e.g. army barracks, dorms

  40. Neisseriameningitidis • upper respiratory tractinfection • adhesion pili • bloodstream brain

  41. Meningococcal meninigitis • second most common meningitis • pneumococcus, most common • fatal if untreated • responds well to antibiotic therapy • penicillin

  42. Laboratory Diagnosis • spinal fluid • Gram negative diplococci • within polymorphonuclear cells • meningococcal antigens • Culture • Thayer Martin agar

  43. Capsule • capsule • inhibit phagocytosis • anti-capsular antibodies • stop infection • antigenic variation • sero-groups • vaccine • multiple sero-groups

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