Causative Organism – Treponema pallidum Characteristics of Treponema pallidum • Spirochaetes or spiral organisms, they are motile, slender. • Do not grow in artificial medium (some treponema are part of the normal oral flora e.g. T.denticulc) • Cannot be seen by light microscopy because they are very thin (0.15 μm), long 5-15 μm. Note: Does not stain with gram stain
Causative Organism – Treponema pallidum Characteristics of Treponema pallidum (Continued) • Can be seen by • Dark field microscopy, by • Phase contract technique • Can be stained by • Silver impregnation • Fluorescent antibody technique • Sensitive to penicillin • They can be propagated by inoculation in rabbits in testes and anterior chamber of eye.
Causative Organism – Treponema pallidum Characteristics of Treponema pallidum (Continued) Treponema Pathogenic Non-pathogenic Oral commensals Pathogenic Non-venereal disease by direct contact T. Denticula T.macrodentium T.microdentium T.pallidum Syphilus T.Pertenue T. carateum T.pallidum A sexually transmitted disease Yaws Pinta Bejal
Mode of Transmission • Direct sexual contact (90 – 96%) • Blood transfusion • Via placenta from infected pregnant mother faetus causes congenital syphilis. • Contact accidental contact E.g. Medical personnel. Source of T. pallidum: Primary and secondary syphilis lesions.
Causative Organism: Treponema pallidum is the causative organism of syphilis. Syphilis can be Acquired Congenital Clinical Features of Syphilis / Symptoms and signs of Acquired syphil • Syphilis is a sexually transmitted disease / a venereal disease Incubation Period: 10 – 90 days (average – 21 days)
3 Stage of Syphilis: 1- Primary syphilis: Primary chancre develops after 2-10 weeks a well defined indurated painless ulcer mainly on the genitalia (90%) and extra-genital on Lips (5-10%). In female, chancre occurs in the cervix. The chancre is painless and exudate is formed in the centre. This fluid is highly infectious and examination by dark field microscopes shows Spirochaetes. There is regional lymphadenopathy. • Primary chancre heals spontaneously without treatment within 3-8 weeks. • Primary syphilis is highly infectious. • Serological tests for Syphilis are positive in 80% cases.
2- Secondary Syphilis: After 6-8 weeks of primary chancre: • Desseminated secondary stage develops. Muco-cutaneous lesion occurs e.g. Skin rash, mucasal ulcers, condylomata on genitalia, Lymphadenopathy, fever headache malaise, alopecia. • Secondary syphilis is highly infectious • Snal – truck mucosal ulcers in the mouth Hepatitis, glomerulonephritis, periostitis, iridocyclitis, choroidoretinitis, arthritis. • Serological tests for syphilis becomes almost uniformly positive. Secondary Stage may follows by the following: a) Cured spontaneously b) Early latent c) Late Latent d) Tertiary stage
Latent Stage: • After the secondary syphilis symptoms subsides, the disease enters a latent stage. • After about 2 years, the syphilis is NOT normally infectious, except from mother to the foetus.
3- Tertiary Syphilis: After 2-20 yrs, tertiary stage develops produces • Gummatous Lesions in perforation of the palate (Roof of the mouth) which interferes with speech • Skin • Bone • Joints Charcoat’s joints • Cardiovascular System E.g. (a) Aortic aneurism (b) Aortic valve incompetence
Central Nervous System: Neurosyphilis E.g. a) Tabes dorsalis b) General paralysis of insane c) Meningovascular sympilis • Tertiary stage is not infectious.
Congenital Syphilis: most distressing and dangerous form of Syphilis. • Early Congenital syphilis: a) Skin: rash maculopapular rash b) Mucosal Lesion: Mucocutaneous lesions c) Hepatospleenomegaly d) Lymphadenopathy • Late Congenital Syphilis: a) Hutchinson’s teeth (Notching of the incisor teeth) b) Mulberry molars, Moon’s molars c) Sadle nose d) Sabre shin (tibia) d) Interstitial keralitis, blindness
f) Deafness g) Bone sclerosis, Arthritis h) Juvenile general paralysis of insane i) Damage of Mental development and other neurological symptoms. j) Stillbirths
Laboratory of Syphilis 1- Dark ground microscopy to demonstrate, Spirochaetes T. pallidum in fluid or exudate from lesions of primary and secondary syphilis. a) Primary Syphilis exudate from chancre b) Secondary syphilis mucous path exudate taken for dark ground microscopy. • Direct immunofluorescent microscopy can be used.
Laboratory of Syphilis (Continued) 2- Serological tests for Syphilis for all stages A. Non-specific Tests B. Specific Tests (for non-treponemal) (for non-treponemal or reagin antibody) (Ag used is Treponemal antigen) (Ag used is cardiolipin) 1- FTA – ABS Test (Florescent Treponemal Antibody Absorption) 2- TPHA (Treponema pallidum Haemagglutination. 3- TPI (Treponema pallidum immobilization) 1- VDRL (Venereal Disease Research Laboratory) 2- RPR (Rapid Plasma reagin) 3- WR (Wasserman Reaction) Congenital Syphilis Baby’s blood IgM –FTA-ABS TEST
Serological Tests for Syphilis (With Interpretation) Stage of disease VDRL TPHA FTA-ABS No Past or Present Infec. • No Past /present Infection (Active Syphilis). • Primary (Early) (Active Syphilis). • Primary (Late) Or (Active Syphilis) in secondary syphilis. • Secondary + Tertiary • Latent Or • Treated syphilis (had infection before)
Serological Tests for Syphilis (With Interpretation) (Continued) Stage of disease VDRL TPHA FTA-ABS • Biological false positive (No Infection by T. pallidum) • Congenital syphilis* * Early primary syphilis – FTA – ABS Positive * After successful treatment – VDRL Negative Note: FTA – ABS after successful treatment remains positive for life But FTA – ABS + TPHA Remain positive * V.D.R.L. is used to see efficacy (effect) of treatment . After successful treatment V.D.R.L. becomes negative.
Serological Tests for Syphilis (With Interpretation) (Continued) Treatment of syphilis : * Penicillin is the drug of choice * Penicillin for 15 days. Primary: Penicillin for 21 days usually followed by 10 injection at weekly intervals. Secondary and Tertiary syphilis : Note: Spirochetes are spiral motile bacteria. Their motility is due to contractile axial fibers run along the bacterial cell.
Spirochetes (spiral bacteria) Borrelia Treponema Leptospira Borrelia recurrentis Borrelia vincenti Pathogenic genera of spirochaetes are : * Borrelia, * Leptaspira, * Treponema Borrelia recurrentis Source : Rodents Disease : • Epidemic Louse borne relapsing fever • Endemic Louse borne relapsing fever Treatment: Tetracycline
Spirochetes (Spiral bacteria) (Continued) Borrelia vincenti : Gram –ve irregular spiral bacteria Culture : Strict anaerobic bacteria, difficult to culture. * Serum enriched media used Anaerobic culture Laboratory diagnosis : Mainly by Microscopic Examination of Gram stained smear only Disease : Borrelia vincenti and Fusobacterium species together produce: • Vincent’s angina (Pharynigitis) or Acute necrotizing ulcerative gingivitis • Gingivo - Stomatitis • Sore Throat Treatment : • Penicillin or Metronidazole • Oral hygiene