Spirochetes Flashcards
are specialized flagella located between the outer membrane and the cell wall of spirochetes, in the periplasmic space.
Axial filaments
• Structure: Composed of multiple protein filaments that wrap around the cell body in a helical fashion.
Axial filaments
• Function:
• Responsible for the corkscrew-like motility of spirochetes.
• Enable the organism to move efficiently through viscous environments like mucus or tissue.
Axial filaments
are structural attachments where the axial filaments are anchored to the cell.
Insertion disks
Protein complexes that secure the ends of the axial filaments to the poles of the cell.
Insertion disks
• Serve as the anchoring point for axial filaments, ensuring stability during movement.
• Play an indirect role in motility by facilitating the tension and relaxation of the axial filaments
Insertion disks
Treponema
6-10
1
Borrelia
30-40
2
Leptospira
2
3-5
• Immunofluorescent stain, dark-field illumination, or iron staining are used
• Seen in tissues with silver impregnation method
Treponema species
• lipid-rich outer membrane, with cytoplasmic filaments
• Do not stain with Gram’s method
Treponema species
• Slender spirals (0.1-0.5 um in width & 5-15 um in length), tightly coiled
• Rotate steadily around their endoflagella (complex, with sheath and core) even after attaching to cells by their tapered ends,
Treponema species
Treponema pallidum Antigenic Structures
• Outer sheath (________)
•________ surrounds the periplasmic space and the peptidoglycan- cytoplasmic membrane complex
•_______ (axial filaments)
• _______ enzyme??
•_____ protein antigens, i.e. cardiolipin
• Develop______ (antibody-like substance)
glycosaminoglycan coating
Outer membrane
Endoflagella
Hyaluronidase
> 100
reagin
Treponema species
• Has never been cultured on______
• Experimentally: infected skin, testes, & eye of rabbits;
• Grown in_____, short periods of time
• O2 need???; best in _____oxygen
• May remain motile in____ days @_____
• Remain viable for at least_____ hours in whole blood or plasma stored at____;
artificial media
tissue culture
Microaerophile; 1-4%
3-6 days at 25°C
24hrs; 4°C
TREPONEMA (3)
(part of the normal flora) seen in oral infections.
T. denticola
T. socranskii
T. pectinovorum
is associated with ulceromembranous gingivitis or pharyngitis, aka
T. vincentii (or Vincent’s spirillum)
Vincent’s angina.
Treponema pallidum = SYPHILIS
A. ACQUIRED SYPHILIS
• Sexual contact______ incubation
• Infectious lesions on (2)
• Intrarectal, perianal, or oral (____cases)
Multiply locally, spread to nearby lymph nodes, then reach the blood stream
• 4 stages
3-6 week
On skin or mucous membranes of genitalia
10-20%
Stage???
: presence of dry, non-tender lesion (hard chancre/Hunterian chancre @ site of inoculation)
- 1º stage
: dry lesions (Condylomata lata or condyloma)
found on other parts of the body
• 2nd stage
: no signs & symptoms (serological test)
Latent stage
- No symptoms but found specific antitreponemal antibodies
• Untreated infection remains latent
LATENT STAGE
GUMMAS (skin, internal organs, CNS, bones, eyes, heart)
CNS = neurosyphilis → paralysis
Eyes → blindness
Heart → aortic damage or aneurisms
TERTIARY STAGE
Congenital syphilis
• treponemes cross the____, infecting the fetus
• usually latent stage of syphilis,_____ to _____ week of gestation
placenta
10th to 15th
• fetal death, miscarriages, stillborn at term
• live but with congenital syphilis in childhood:
• symptoms????
Interstitial keratitis
Hutchinson’s teeth
Saddlenose
Periostitis
damage to mental development or other neurological symptoms
Cranial nerve
Hurchinsons
8
Vestibulochochlear
Non venereal treponemas
Pertrnur
Endemicum
Carateum
______: Caused by Treponema pallidum pertenue
_____: Caused by Treponema carateum
_____: Also known as____, caused by Treponema pallidum endemicum
Yaws
Pinta
Endemic syphilis; bejel
The genus Treponema includes four pathogenic species for humans:
1. Treponema pallidum subsp. pallidum: Causative agent of_____.
2. Treponema pallidum subsp. pertenue: Causative agent of_____.
3. Treponema pallidum subsp. endemicum: Causative agent of endemic syphilis (_____).
4. Treponema carateum: Causative agent of_____
syphilis
yaws
bejel
pinta
T. pallidum
Primary Stage
• Onset:_____ days after infection.
• Lesion Characteristics:
• Single chancre at the site of inoculation, resulting from the inflammatory response.
• Appearance: Erythematous, firm, non-tender lesion with a clean surface and raised border.
• Lesion contains numerous treponemes and is highly infectious.
• Common Locations:
• Men:_____.
• Women:_____(may go unnoticed due to non-tender nature).
• Both sexes:_____ (often undetected).
• No systemic signs or symptoms during this stage.
10 to 90
Penis
Cervix or vaginal wall
Anal canal
T pallidum
Secondary Stage
• Onset:______ after primary lesion development.
• Clinical Features:
• Fever, sore throat, generalized lymphadenopathy, headache.
• Lesions on mucous membranes and a generalized rash:
• Types: Macular, papular, follicular, papulosquamous, or pustular.
2 to 12 weeks
T pallidum
• Unusual feature: Rash can involve______.
• Secondary lesions are highly infectious.
• Duration: Can last several weeks, may_____, or be mild and unnoticed.
palms and soles
relapse
Tertiary Stage
• ________:
• Begins after secondary lesions heal.
• Early latent syphilis: Within 1 year of infection.
• Late latent syphilis: After 1 year.
• Outcomes of untreated latent syphilis: • Biological cure in one-third of patients (loss of serologic reactivity). • Lifetime latency in one-third (with reactive sera). • Progression to tertiary syphilis in one-third.
Latent Period
T pallidum
Clinical Manifestations (decades later): • \_\_\_\_\_\_\_\_: Skin, bones, liver (benign tertiary syphilis). • \_\_\_\_\_\_\_\_\_: Degenerative CNS changes. • \_\_\_\_\_\_\_\_\_: Aortitis, aneurysms, and aortic valve insufficiency.
Patients with tertiary syphilis are not_____.
• Rare in developed countries due to effective antimicrobial treatment
Granulomatous lesions (gummas)
Neurosyphilis
Cardiovascular syphilis
infectious
T pallidum
Dark-Field Microscopy: • Requires expertise and special equipment. • Visualization of motile treponemes is diagnostic for\_\_\_\_\_
primary syphilis
Nontreponemal Tests
Vdrl
Rpr
Nontreponemal Tests:
• Detect ______targeting lipids released from damaged cells.
• Use \_\_\_\_\_\_complex as the antigen (from bovine hearts). • Advantages: • Excellent for screening. • Low-cost and easy to perform. • Rising/falling titers correlate with clinical status. • Limitations: • Lower specificity; false positives may occur.
reaginic antibodies
cardiolipin-lecithin-cholesterol
Widely Used Nontreponemal Tests:
• Requires a microscope to observe flocculation of cardiolipin-antibody complexes in serum or CSF.
——————
• Uses charcoal particles for macroscopic visualization.
• More commonly used than VDRL.
• Positive results require titration and confirmation with a treponemal test
Venereal Disease Research Laboratory (VDRL):
Rapid Plasma Reagin (RPR):
NONSPECIFIC, NONTREPONEMAL TESTS
Screening purposes; efficacy of therapy
Lipid-antigen particles dispersed in serum and flocculate with reagin
Antigens:_______
• Detect_______
(nontreponemal antibodies)
cardiolipin, cholesterol, & purified lecithin
reagin or Wasserman antibodies
4 non treponemal tests
Rapid plasma reagin (RPR) card tests - uses cardiolipin (not for CSF)
Venereal Disease Research Laboratory (VDRL)
Unheated serum reagin (USR) test
Toluidine red unheated serum test (TRUST)
SPECIFIC, TREPONEMAL TESTS | Confirm positive nontreponemal results
(5)
• T pallidum-particle agglutination (TP-PA) - Gelatin particles sensitized with TP
• T pallidum hemagglutination (TPHA)
• Microhemagglutination T pallidum (MHA-TP) Sheep erythrocytes
• Enzyme immunoassay (EIA) for T pallidum
• Fluorescent treponemal antibody absorbed(FTA-ABS)
Treatment:
__________
__________(primary/secondary syphilis)
If allergic,_______(3)
Benzylpenicillin
Procaine penicillin
erythromycin, tetracycline, or chloramphenicol
What kills the spirochetes?
• Drying/desiccation
• Detergents
• Elevation of the temperature to 42°C
• Trivalent arsenical, mercury, bismuth
Common Treponemal Tests:
____________
• Uses gelatin particles coated with treponemal antigens.
• Agglutination indicates antitreponemal antibodies.
___________
• Automated, widely available, and comparable to TP-PA.
__________
• Uses fluorescent-labeled antibodies to detect treponemal-specific antibodies on a prepared slide.
• Less commonly used due to subjectivity and higher cost.
___________
• Automated treponemal test followed by nontreponemal test.
• Higher false-positive rates, so CDC recommends traditional approach.
Treponema pallidum-particulate agglutination (TP-PA)
Enzyme Immunoassays (EIAs)
Fluorescent Treponemal Antibody Absorption (FTA-ABS)
Reverse Sequence Screening:
Yaws
• Causative Agent:_______
• Geographic Distribution:
• Tropical regions of Africa, South America, India, Indonesia, and the Pacific Islands.
• Not present in the\_\_\_\_\_. • Transmission:\_\_\_\_\_\_\_ • Clinical Course: • Early lesions: Elevated, granulomatous nodules. • Resembles syphilis but with distinct lesion presentation in primary and secondary stages.
Treponema pallidum subsp. pertenue.
United States
Direct contact with infected skin lesions.
Endemic Syphilis (Bejel)
• Causative Agent:_________
• Geographic Distribution:
• Middle East and arid, hot regions worldwide.
• Transmission: \_\_\_\_\_\_ • Clinical Course: • Primary and secondary stages present as\_\_\_\_\_ that often go unnoticed. • Progression to\_\_\_\_\_\_ of the skin, bones, and nasopharynx can occur. • Dark-field microscopy is not useful due to the presence of normal oral spirochetal biota. • Contributing Factors: Poor hygiene and crowded living conditions.
Treponema pallidum subsp. endemicum.
Direct contact or sharing contaminated eating utensils.
papules
gummas
Pinta
• Causative Agent:_______
• Geographic Distribution:
• Tropical regions of Central and South America.
• Transmission:\_\_\_\_\_\_ • Clinical Course: • Begins with scaling, painless papules. • Followed by an erythematous rash that becomes hypopigmented over time.
Treponema carateum.
Person-to-person contact; rarely sexual.
Venereal Syphilis
1. Transmission:
• _______treponemal diseases are spread through nonsexual contact.
- Geography:
• Occur in tropical and arid regions with poor hygiene and overcrowding. - ______Stage:
• Rare in nonvenereal treponematoses, while venereal syphilis commonly progresses to tertiary manifestations if untreated. - Congenital Infections:
• Nonvenereal treponemal diseases do not cause congenital infections, unlike syphilis.
Nonvenereal
Tertiary
