Exam #6: STD II Flashcards
What causes syphilis?
Treponema pallidum (spirochete)
List the characteristics of Treponema pallidum.
Thin Gram (-) spirochete
Motile
Microaerophilic
*Does NOT grow in cell free culture, very difficult to grow
Describe the structure of Treponema pallidum.
Gram (-) cytology, but DOES NOT gram stain
Flexible
Peptidoglycan surrounds axial fibrils
Wound endoflagella
Cell wall & axial fibrils are covered by an outer bilayered membrane
How is syphilis diagnosed?
Dark-field micrscopy
Direct fluorescence
Antibody/ serology is most common
How is primary syphilis characterized?
1+ skin lesions (chancres)
Hard
Indurated
Painless
What causes the lesion & how long does it last?
Inflammation causes the lesion
Onset is 10-90 days post initial infection
Lasts 2 weeks–>2 months
How is secondary syphilis charactertized?
Disseminated disease
- Flu-like syndrome
- Prominent skin lesions on plams & soles
- “Condylomata lata”
What are Condylomata lata?
Raised lesions in skin folds associated with secondary syphilis
How is latent syphilis characterized?
Asymptomatic period
- Lasts years to decades
- Can relapse into secondary syphilis
- Transmission possible esp. from mother to child
How is tertiary syphilis characterized?
Diffuse, chronic inflammation
Can cause devastating destruction of virtually any organ/ tissue
Gumma
What is a gumma?
Granulomatous lesions that may be found in bone, skin, & other tissues i.e. brain & heart associated with tertiary syphilis
What were the outcomes of the Tuskegee syphilis experiment?
IRB
Informed consent
What is congenital syphilis?
Mother-to-child transmitted syphilis
- Often terminates pregnancy, but when it doesn’t:
- Chronic rhinitis–>saddle nose
- “Condylomata lata”
- Teeth & bone malformation, blindness, deafness, & cardiovascular syphilis
What is Hutchinson’s triad?
Small
Malformed
Widely spaced teeth
What are the serologic tests for syphilis? What are their targets?
Treponemal test= detects antibody specific to T. pallidum
Nontreponemal= measures antibody directed against cardiolipin
When will a person start to exhibit a positive response to serologic tests through the infectious process?
Four weeks
How is syphilis treated?
PCN
What is NGU?
Non-gonococcal urethritis
i.e. when Gonorrhea & Chlamydia don’t cause urethritis
What are the most common causes of NGU?
Mcoyplasma genitalium & Ureaplasma urealyticum
List the characteristics of Mcoyplasma genitalium & Ureaplasma urealyticum.
DO NOT have a cell wall
Not stained
Pleomorphic
Plasma membrane contains sterols
What is the characteristics morphology of Mycoplasma genitalium?
“Fried-egg” appearance
What is Mycoplasma genitalium resistant to?
Doxycycline
What is Mycoplasma genitalium susceptible to?
Azithromycin
How is Ureaplasma treated?
Doxycycline
