Exam #6: STD II Flashcards Preview

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Flashcards in Exam #6: STD II Deck (34):
1

What causes syphilis?

Treponema pallidum (spirochete)

2

List the characteristics of Treponema pallidum.

Thin Gram (-) spirochete
Motile
Microaerophilic

*Does NOT grow in cell free culture, very difficult to grow

3

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

4

How is syphilis diagnosed?

Dark-field micrscopy
Direct fluorescence
*****Antibody/ serology is most common*****

5

How is primary syphilis characterized?

1+ skin lesions (chancres)
Hard
Indurated
Painless

6

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

7

How is secondary syphilis charactertized?

Disseminated disease
- Flu-like syndrome
- Prominent skin lesions on plams & soles
- "Condylomata lata"

8

What are Condylomata lata?

Raised lesions in skin folds associated with secondary syphilis

9

How is latent syphilis characterized?

Asymptomatic period
- Lasts years to decades
- Can relapse into secondary syphilis
- Transmission possible esp. from mother to child

10

How is tertiary syphilis characterized?

Diffuse, chronic inflammation
Can cause devastating destruction of virtually any organ/ tissue
Gumma

11

What is a gumma?

Granulomatous lesions that may be found in bone, skin, & other tissues i.e. brain & heart associated with tertiary syphilis

12

What were the outcomes of the Tuskegee syphilis experiment?

IRB
Informed consent

13

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

14

What is Hutchinson's triad?

Small
Malformed
Widely spaced teeth

15

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

16

When will a person start to exhibit a positive response to serologic tests through the infectious process?

Four weeks

17

How is syphilis treated?

PCN

18

What is NGU?

Non-gonococcal urethritis

i.e. when Gonorrhea & Chlamydia don't cause urethritis

19

What are the most common causes of NGU?

Mcoyplasma genitalium & Ureaplasma urealyticum

20

List the characteristics of Mcoyplasma genitalium & Ureaplasma urealyticum.

DO NOT have a cell wall
Not stained
Pleomorphic

Plasma membrane contains sterols

21

What is the characteristics morphology of Mycoplasma genitalium?

"Fried-egg" appearance

22

What is Mycoplasma genitalium resistant to?

Doxycycline

23

What is Mycoplasma genitalium susceptible to?

Azithromycin

24

How is Ureaplasma treated?

Doxycycline

25

What is Chancroid caused by?

Haemophilus ducreyi

26

List the characteristics of Haemophilus ducreyi.

Gram (-) pleomorphic coccobacillus

27

What is required for the growth of Haemophilus ducreyi ?

X & V factor

28

What are the symptoms of Chancroid?

Genital ulcers
- Painful chancre (vs. painless)
- Soft (vs. hard)
- Multiple vs. 1 lesion
- Lymphadenopathy

"You do cry with ducreyi"

*Note that diagnosis is challenging because labs are NOT set up to detect b/c of low prevalence

29

How is Haemophilus ducreyi i.e. Chancroid treated?

Macrolides

30

What causes Donovanosis or Granuloma inguinale?

Klebsiella granulomatis

31

What are the symptoms of Donovanosis?

- Primary lesion is ulcerated
- Lesions are painless & bleed easily
- Significant genital damage can occur
- Hard

32

How is Donovanosis diagnosed?

Donovan bodies

33

Describe the medical decision making process when a patient presents with a genital ulcer.

1) Syphilis vs. Genital Herpes?
2) IF NOT, then chancroid or donovanosis

34

M. genitalium vs. Ureaplasma & doxycycline?

M. genitalium is resistant!
Ureaplasma is susceptible

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