1. INFECTIOUS DISEASE OF
PATHOLOGY
(Bacterial Diseases)
Spirochetes
Dr. Naila Awal
(Postgraduate student)

2. Spirochetes with their diseases
1)Treponema pallidum- Syphilis
Non veneral treponemotoses
2)Borellia recurrentis- Relapsing fever
Borellia burgdorferi- Lyme disease
3)Leptospira- Leptospirosis

3. Treponema pallidum
• Pathogenesis•
•
•
•
•
Agent- Treponema pallidum
Host-Human
Disease- Syphilis
Reservoir- Patient of syphilis
Source of infection-
Primary syphilis- Exudate of ulcer containing bacteria
Secondary syphilis- Muco cutaneous rash
Blood- for both primary & secondary.

4. • Mode of transmission1)Acquired syphilis Sexual contact
Blood
2)Congenital syphilis From mother- fetus

5. Primary syphilis
• T.pallidum can not penetrate intact skin. They
enter into the body through abraded skin
invade locally into blood vessels & lymphatics
multiply within 3-4 weeks they produce local
lesion.
Papule macule vesicle (fluid accumulates) vesicle
rupture painless ulcer Hard chancre (Hallmark)
This is highly contagious stage. Within next 24weeks, ulcer heals spontaneously.

6. Secondary syphilis
• It is the disseminated stage of the disease.
• 4-8 weeks after healing ulcer, patient develop
maculopapular rash involving all over the body
including palm & sole
( characteristics)
• When the lesion occurs in the moist area, peri
anal region condylomata lata
( Hallmark)

7. Tertiary syphilis
• It occurs 3-4 yrs after.
• Manifestation1) Cardiovascular syphilis- Aneurysm, Aortic
regurgitation.
2)Neurosyphilis –Chronic meningovascular
disease, tabes dorsalis & generalized paresis.
3) Gumma- Skin, Bone

8. Latent Syphilis
• Here the patient is infected with the
bacteria but he/she is asymptomatic. The
serological test is positive.
• Types-2
Latent syphilis
Early latent (within 2yrs)
Late latent (3-4yrs after)
May progress to tertiary syphilis

9. • Clinical significance1)In early latent patient ,patient remains
infectious but in late latent patient
becomes non- infectious.
2)It is very dangerous condition.
• Confirmation1) Patient have no S/S
2)Serological test positive

10. Congenital syphilis
• Definition- Syphilis that are transmitted
from mother to fetus when mother is
attacked byprimary & secondary syphilis
rarely in latent syphilis
• Transmission occurs after16th weeks of
pregnancy b/c of atrophy of
syncytiotrophoblast layer.

11. S/s
• Infantile syphilsChorioretinitis
Desquamating skin rash
Viseral & bone changes
Osteochondritis, Periostitis
Hepatic & pulmonary fibrosis
• Late congenitalNotched central incisor teeth
Intestitial keratitis
Deafness(8th nerve damage)
Hutchinson traid

12. Diagnosis
• Just after delivery,if mother is untreated with
penicillin, both VDRL & TPHA of baby & mother
will be done.
Mother
VDRL- 1:4
TPHA- 1:4
Baby
1:16
1:4
• So 1 month afterVDRL- 1:4
1:4
Comment
Baby is infected
May be it comes from
mother /produced by the baby.
1:8
1:2
Form within the baby
Comes from mother.

13. Diagnosis
• SampleA)Exudate- from primary chancre
B)Serum
• Lab procedureA) Exudate1)Dark field microscopyBright ,slender, spiral bacteria with crock-screw &
flexion-extension motility
2) Immunofluroscence microscopy

15. 3)Staining
a)Silver staining- Fontena’s stain
Warthin starry staining
b)Immunofluroscence staining- I/F dye is
tagged with anti-treponemal Ab.

16. Warthin starry stain

17. B) Serum(serological test)
• 1)Non specific testI)VDRL
II)RPR (Rapid plasma reagin)
• Now-a-daysIII)UST (Unheated serum test)
IV)TRUST (Tolludin red Unheated serum test)

18. • SpecificTPHA (Treponema pallidum haemagglutination)
TPI (Treponema pallidum immobilization )
IgM
FTA-Abs
(Fluorescence treponemal Ab absorption test)

19. Histopathology
Primary syphilis• Surface of the ulcer- Treponema are visible in
warthin starry and Immunofluroscence staining.
• Chancre contains infiltration of plasma cells
with scattered macrophages & lymphocytes and
a proliferative endarteritis.

20. Secondary syphilis
• Mucocutaneous lesion shows infiltration of
plasma cell & obliterative endarteritis.
Tertiary syphilis• GummaCenter- Coagulative necrosis
Margin- palisading macrophages & fibroblasts
surrounded by mononuclear leukocytes chiefly
plasma cells. Treponema are scanty in gumma .

21. VDRL
• Advantage1)Very simple
2)Can be done in field level
3)The result may be
quantitive & qualitative.
4)The test is sensitive 70%
in primary syphilis & 98%
in secondary syphilis.
5)Neurosyphilis can be
diagnosed.
• Disadvantage
1)The Ab against Tp takes
about 3-5 weeks times to
become appear. So
before 3-5 weeks it will
show false negative.
2)May give false positive.

22. TPHA
• Advantage1)Very simple
2)Can be done in field level
3)The result may be
quantitive & qualitative.
4)TPHA is very sensitive
5) It detects specific Ab.
5)Can detect neurosyphilis
& latent syphilis.
• Disadvantage
Once become positive,
remains positive for long
time even in cured
patient.

23. Neurosyphilis
• Lab DiagnosisSpecimen- 1)Serum 2)CSF
Lab test1)Serum• TPHA- must be positive
• VDRL-Reactive/ Non reactive
2)CSF• TPHA- positive
• Cell count-lymphocytosis
• Protein-Increase.

24. Serological problem in syphilis
positive HIV
1)Confusing clinical s/s
2)Lack of serological response
3)VDRL,TPHA- non reactive
4)Due to CD4 & CD4:CD8Tp Ab takes long
time to disappear.
5) May be high Ab titer due to B cell
activation.