This document provides information on the bacteria Treponema pallidum, which causes syphilis. It discusses the morphology, structure, growth, transmission and pathogenesis of T. pallidum. It also summarizes the clinical manifestations and stages of syphilis, including primary, secondary, latent and tertiary syphilis. Laboratory methods for diagnosis are outlined, including darkfield microscopy, serological tests such as the non-treponemal tests (VDRL, RPR) and treponemal tests (TPHA, FTA-ABS).

1. DR.FARIA MALIK
HEAD OF MICROBIOLOGY
SIMS

2. SPIROCHETALIS
TWO FAMILIES
1. SPIROCHETACEAE: 0.1-0.3um
• 3 GENERA of free-living, large spirals
2. TREPONEMATACEA: 3 genera
• Treponema
• Borrelia
• Leptospira

3. TREPONEMA
• Treponema pallidum subspecies pallidum
SYPHILIS
ENDEMIC SYPHILIS
• Treponema pallidum subspecie pertenue
YAWS
• Treponema pallidum subspecie carateum
PINTA

4. MORPHOLOGY
• Gram negative bacilli, cockscrew-shaped
• Slender spirals: length 5-15um * 0.2um
• regular tight coils at l um intervals 8-
14/cell
• Active motility around flagellum by
attaching to tissue by tapering end, secrete
hyaluronidase
• Sluggish, drifting; active motility

5. structure
• Outer sheath or glycosaminoglycan coat
• Outer membrane…PPG/structural integrity
• Periplasmic space inside for endoflagella
• Endoflagella start at ends, overlap in mid
Wind around axil
• Inner membrane; osmotic stability
• Protoplasmic cylinder

6. GROWTH
• T pallidum: In Vitro not grown:
non pathogenic Rieters strain can be grown
• Can Maintain at 25 C , 4-7 days
anaerobic,albumin,NaHCO3,pyruvate,serum
• Rabbit epitheleal cells:
multiply several generations 10-100
• Division:
transverse fission : doubling time 30hours
• Microaerophilic 1-4% O2
• Blood:Transfusiontransmissionstore2-6Cfor3-5days/low risk,screeneddonors.survive 24hrs 4c

7. HISTORICAL NAMES
Great pox" in the 16th
century
• Scotland, Grandgore
• French army outbreak morbus gallicus French dis
. OR the la maladie anglaise (the English Dis
• Italians called it "Spanish disease", & “Italian
disease" or “Neapolitan disease”,
• Russians called it : “Polish disease",
• Arabs called it the "Disease of the Christians”.
terms "lues" and "Cupid's Disease" were used.

8. HISTORY
• ORIGIN
• Europe 15 century Mediterranian-epidemic
• New World Columbus crew got it West Indies, so
reached Spain
• Africa endemic for centuries-Europe by armies &
civil populations
• 18 Century d/d gonorrhea
• 1905,Schaudinn and Hoffman etiologic agent
• 1906 Wassermann serological tests introduced

9. TRANSMISSION
1.Intimate Contact with infected person,
• From spirochete containing lesion of
skin/mm (genitalia, mouth, rectum) to
skin/mm
• Sexual/accidental; physician, pathologist
2. Pregnanat woman to fetus
3. Blood transfusion
• Site of Inoculation: Genetalia/genital tract
• Survival outside host: limited

10. PATHOGENESIS
• No enzymes & toxins produced
• Infects endothelium of small BV called “
Endarteritis
affects BV of brain & CVS seen in tertiary syphilus
Perivascular areas affected.
After invasion organisms multiply and disseminate
rapidly and widely via the above routes

11. PRIMARY SYPHILUS
• CHANCRE or ULCER: painless
• In 3 weeks at inoculation site ;
• shallow, well defined, indurated edges, red
surface, exude serum
• profuse shedding of T.pallidum.
• accumulation of mononuclear WBC, lymph,
plasma cells; capillary endothelium swells.
• Regional L Nodes enlarge
• Resolution by fibrosis in 3-6 weeks

12. CLINICAL MANIFESTATION
ACQUIRED SYPHILIS
• Human host, sexual contact
• External genitalia: Abraded skin & intact mm
• Other sites: 10-20%
• PRIMARY LESION: 2-10 WEEKS
PAPULE: Local multiplication, breaks to ulcer
HARD CHANCRE: hard base
Inflammatory cells: lymphocytes & plasma cells

14. Chancre on tongue

15. SECONDARY LESION
• Maculo-papular rash: red on palms & soles
• Condylomata: moist, pale, papules
• anogenital, axillae, oral
• Immunological: meningitis, nephritis
• chorioretinitis, hepatitis
• Highly infectious stages, rich in spirochetes
• Spontaneous cure in primary & secondary

16. Constitutional symptoms
• Low grade fever
• Malaise
• Anorexia
• Weight loss
• Head ache, myalgias
• Lymphadenoathy
• Hepatitis, pharyngitis, nephritis, meningitis

19. Lesions on back

20. Latent syphilis
LATENT DISEASE:
Early-latent ----------< 2 yrs of infection;
Late latent----------- > 2 yrs
Pt no symptom but is sero-reactive
not effected by therapy .
Untreated: 40% with symptom; 60% no symptom
• Sequelae of Syphilis 30% cure,
• 30% latent,
• 40% tertiary

21. SEQUAELAE
1 Spontaneous cure; no t/m
• 1/3 primary & secondary cases
2 Latent: 1/3
No lesions appear but serological tests
positive denoting infection.
EARLY LATENT: lasts 1-2 yrs of secondary
stage, symptoms may reappear & pt
infective

22. LATE STAGE OR TERTIARY
SYHPILIS 30% UNTREATED
PTS
• Duration: lasts many years; 3-10 yrs after 2 sta
• Sparse spirochetes
1. GUMMAS;
• benign tertiary syphilis
• bone, skin organs-liver, stomach
• dermal lesions,
• immunologic reaction

23. NEUROSYPHILIS
• EARLY: 1/3 pts effected but half develop
LATE: ½ patients
• 5 CLASSIC;
• paralytic dementia seizures ,optic .
• tabes dorsalis optic atrophy,
• amyotropic lateral sclerosis,
meningovascular syphilis, gumma cord

24. 3.Cardiovascular syphilis
• Syphilitic Aortic & Pulmonary arteritis;10-40 yrs
after primary . Stenosis-angina, MI, death

25. CONGENITAL SYPHILIS
• : Transplacental infection 10-15 wks
spirochetes enter blood of dev fetus and
disseminate 700 cases; 1988 USA
• Mortality untreated: 25% miscarriage, still
Late stigmata; 40% hepato-splenomegaly,
jaundice, anaemia, pneumonia, snuffles
bone, skin lesions.Hutchison teeth,saber
shin, saddle nose, frontal boss, 8 nerv deaf

26. SEROLOGICAL RESPONSE
Primary syphilis
• AB: 1-4 weeks after chancre. FTA-ABS + first ,
• followed 1 week later by trep.specific tests &
cardiolipin tests.
Secondary syphilis ; all positive
• Latent: Reactivity of cardiolipin decrease
• Late syphilis cardioloipin: reactive/weak/non
reactive; specific trep tests remain +, titre low

27. LABORATORY DIAGNOSIS
SPECIMENS
1 SEROUS FLUID chancre, secondary
skin lesions (moist areas) motile T pallidum
spirochetes seen in primary, secondary, early
congenital, infectious relapsing syphilis.
• Within a few hours of taking AB , treponemes
disappear, so ask pt. of H/O drugs.
2. BLOOD: 3-5ml serum/plasma
(should not hemolysed, lipemic, contaminated).
• CAUTION: GLOVES,SAFE WASTE DISPOSAL

28. • 1 MICROSCOPY
• Dark field direct vision ; viable & actively
motile in primary & active secondary lesion
• Direct Florescent antibody; DFA
exudate taken on slide or capillary
tube
• Special stains
• 2 Animal inoculation 10-100generations in
rabbit
• 3 SEROLOGICAL REACTIONS

29. Dark-field microscopy

30. Silver impregnation

32. Flourescent stain

33. SEROLOGICAL TESTS
• 1.Non Treponemal Tests
• Wassermanns 1906 used syphilitic tissue as a
complement –fixing antigen to detect antibody
induced by T.pall:
beef heart, cardiolipin, lecithin similar properties
• CARDIOLIPIN-LECITHIN ANTIGEN used in
1. Complement fixation tests;
Wassermann & Kolmer
• 2 Flocculation tests: VDRL, Hinton, Rapid reagin
• 90% Reactive in secondary,78% each in primary
& secondary: false +&- results.

34. NON TREPONEMAL
ANTIGEN
• AB: Pt serum
• Ag: beef cardiolipin
• AB: REAGIN AB: IgM, IgG
VDRL
• RPR
• POSITIVE: primary, secondary stage;
• titre decrease with tm

35. REAGINIC AB
• REAGIN is a mixture of IgM & IgG AB
• Formed against Cadiolipin-cholestrol-
lecithin.
• Cardiolipin is an important component of
treponemal Ag
• Cardiolipin also extracted from normal
mammalian tissue eg beef heart; so cross
reactions

36. NON SPECIFIC CARDIOLIPIN
REAGIN TESTS
• SCREENING TESTS:
• VDRL:
Heat inactivated serum (to destroy
complement) is reacted with freshly
prepared cardiolipin- cholestrol-lecithin Ag
and resultant flocculation read
microscopically by 10x.
• Quantitation done by double dilution

37. RAPID PLASMA REAGIN
RPR
• Plasma/serum can be used
• CCL Ag has choline chloride added.
No heat-inactivation needed
• Carbon added to Ag which are trapped in
floccules on a card.
• Result read Macroscopically .Can quantify
• Ag stable, ready to use state –6months at 4-
10 C

38. TOULIDINE RED UNHEATED
SERUM TEST(TRUST)
• Red instead of black particles of RPR used to
visualise the reaction.
• Red particles caught in mesh of Ag &AB complex
• Result in few minutes if agitated
• can keep room temperature.

39. FALSE POSITIVE
REACTIONS
• Biological false positive ( BFP )reactions
• Low titres 1/8 or < infections, immune disorders.
• Non-treponemal tests & Reaginic Ab reacts with
200 other Ag
• Transient < 6 months BFP: Malaria, hepatitis
virus pneumonia, viral exanthemas, pregnancy
trypanosomiasis, vaccinations. Titre 1:8
• Long term BFP
SLE, RA, TB, leprosy, cancer, narcotics addict.

40. INCORRECT RESULTS BY
NON SPECIFIC CARDIOLIPIN
TEST• PROZONE:
V. high cardiolipin titres as in secondary
syphilis. Excess AB prevents normal reaction,
False negative or non reactive, rough , grainy
reaction. Perform with undiluted and I:20 diluted
• Incorrect test performance
• HIV: Immunosuppression –non reactive
B cell activation – prozone
No fall in titre after T/M due to
HIV coinfection

41. Benefits of non treponemal tests
• Widely available
• Automation & can be done in large
numbers
• Low cost
• Quantified: diagnostic & therapeutic
evaluation
DRAWBACK
Not sensitive in early syphilis; + in few weeks

42. INTERPRETATION
• Non specific AB to cardiolipin formed in 3-
5 weeks of infection, or 2 weeks after
chancre.
• Secondary syphilis maximum AB,100%
reactivity
• Negative : late, latent syphilis &
with t/m titre falls
after 6 months of primary &
12-18 months of secondary syphilis

43. SPECIFIC TREPONEMAL
TESTS
• Confirm non trep tests & in late syphilis
• NO BFP; IgG persist long i.e years even after
T/M; Rapid, easy to perform & inexpensive
1. TPHA : T.pallidum haemagglutination assay
2. TPPA : T.pallidum particle agglutination assay
3. IC (Immuno-chromatographic): Rapid strip test
4. Latex agglutination: Syphilis fast test
5. FTA-ABS:
(Flourescent treponemal antibod absorption test)
6. EIA (enzyme immunoassays)

44. Treponemal tests
• Done to determine if non-treponemal test
truly or falsely positive
• If both positive, pt has syphilis
• Not useful as screening tests as once +,
life long positive, independent of therapy
• No dilution done; so reactive/non
reactive/inconclusive
• Costly esp when large no donors screened

45. TPHA
• POSITIVE IN PRESENT & PAST INFECTION
• Titres detected in 4th
week or longer
• Primary syphilis: low titres 80-320
• Secondary syphilis high 5120 or >
• Late/latent syphilis drop in tires but still positive
20-30 yrs after T/M
• Microtitration plate coated with sheep or avian
RBC sensitized/coated with T.pallidum Ag
(Nicholes strain)Add serum .Agglutination- matt,
nonagglut-button. (AB to commensal Trep.
Removed by non-pathogenic Reiter’s treponemes)

46. HEMAGGLUTINATION TEST
• Automated, easy , inexpensive, specific,
sensitive
• IgM-FTA-ABS TEST
Congenital syphilis:
• Passive AB maternal
• Fetal active infection IgM
• Not reliable, so abandoned.

47. TPPA & IC
• Gelatin particles used instead of RBC, stability
better
• Positive clumping seen
• Modification: capillary whole blood used instead
of venous
• IC: Rapid 15 minutes, simple, low cost for
specific AB to Trep pallidum (recombinant Ag)
in serum, plasma. 100ul serum in tube , strip
immersed and look for 2 pink bands in +

48. LATEX SYPHILIS FAST TEST
• Latex coated with Trep.pall Ag added to 20
ul serum on a card. Positive test in 8 mins
TREATMENT
• Pencillin 0.03units/ml single I/M injection
• treponemicidal < 1yr duration
• Older/latent disease 3 doses at weekly
interv
• Congenital: i/v

49. OTHER SPECIFIC TESTS
• T.P Immobilization Test(TPI) A suspension of
living & motile treponemes maintained in rabbit
testes are immobilized by reaginic antibody and
complement, seen by dark field microscopy.
Difficult,expensive and false + for non venereal
treponemes.Done in research labs to compare
other tests
• RIETER PROTEIN COMPLEMENT FIXATION
TEST;Ag extract of non virulent strain Reiter
cultured in vitro. Group Ag ;false +/-

50. FLOURESCENT ANTIBODY
TEST in reference lab
• First test to be positive in 3-4 weeks in Primary
sphilis
• Trep.antibody detected by flourescein labeled anti
human antibody
• Used; congenital syphilis, late stage syphilis,
positive reaginic test
• Sensitive, reliable
• FTA;( Florescent Tryp. Antibody test)Nichol’s
strain organisms used as AG ,fixed on slide,test
serum applied,allowed to react. Then layered by
fl.antihuman AB seen by fl.microscope
• Expensive, time consuming

51. CONGENITAL SYPHILIS
• INFANTS: Symptoms suggestive
• Skin lesion/nasal discharge: motile treponemes by
dark field microscopy
• Serology Reactive specific test at 3 months ,
maternal IgG
• Active Infection IgM raised
Higher AB titre than mother and
continues to rise
• MOTHER ; AB tested with infants

52. TREATMENT
• PENCILLIN MIC 0.004U/ml
• Most sensitive organism but R increasing
• Early syphilis 0.03 units/ ml serum 7-10 days
totally arrests disease
• Late 21 days
• Erythromycin, tetracycline, cephaloridin but less
passage to fetus so cong.syph can occur
• Evaluate: 3 months quantitative cardiolipin tests
• Relapse titre increases

53. PREVENTION
• AIDS association so avoid drug abusers,
STD pts, HIV pts
• T/M case contacts, examine them, treat as
primary syphilis as long incubation gives
time for prevention.