Unit1 Micro

Question 1

Treponema pallidum Bacteriology

Answer 1

syphilis
small, spirochete, don’t survive outside host, surface of spirochetes are non-immunogenic and they also are believed to down regulate the host’s TH1 response.

Question 2

Treponema pallidum Pathogenesis

Answer 2

syphilis
Stage 1: 3 to 12 weeks,ulcer
Stage 2: 4 to 10 weeks, Macropapular rash, condylomata lata, patchy alopecia, consittutional symptoms
-High antibody titers
Latent Syphilis: either symptoms come and go pt remins infectious
Stage 3: -Granulomas (gummas) liver, brain, bones and testes
-Cardiovascular syphilis, syphilitic menegitis, meningovascular syphilis (5 to 10 yrs), parenchymal nuerosyphilis (15 to 20 yrs)

Question 3

Argyll- robertson pupil

Answer 3

Test for nuerosyphilis:

-1 or more pupils does not constrict normally to light, but does constrict during accommodation

Question 4

Treponema pallidum Lab tests

Answer 4

Darkfield microscopy

RPR or VDRL ( tests for Reagin through flocculation)

Question 5

Reagin

Answer 5

Bulk nonspecific antibody population raised with a spirochete infection, detectable through RPR or VDRL

Question 6

Congenital Syphilis

Answer 6

40-50% of babies with infected mom and spontaneously aborted

surviving babies develop sever secondary syphilis

Question 7

Treponema pallidum Treatment

Answer 7

Single injection of benzathine penicillin G

Question 8

Jarisch-Herxheimer reaction

Answer 8

24 flu like symptoms seen after treatment of a spirochete

Question 9

Yaws (Treponema pertenue)

Answer 9

Ancestral form of syphilis
3 phase disease but without neuro or cardiac involvement
Gives positive RPR
Tropical disease spread by direct contact with cutaneous lesion

Question 10

Pinta (Treponema carateum)

Answer 10

Just cutaneous involvement
Central and south america
Gives positive RPR

Question 11

LOS vs LPS

Answer 11

LOS is a truncated form of LPS
LOS is less immunogenic than LPS
LOS causes local inflammation, LPS causes systemic
LOS in Niesseria

Question 12

Differences btw N. meningitidis and N. Gonorrheae

Answer 12

N. gonorrhoeae is not incapsulated, even more sensitive to dehydration and cold, antibiotic resistance is more common, and there are hundreds or serotypes (no vaccine)
only N. meningococci ferment maltose

Question 13

HIV introduction into humans, where,when what?

Answer 13

From chimpanzees
First documented case in 1902 to 1921 in Cameroon.
Three independent introduction of SIV into humans occured.

Question 14

Demographics of new HIV infections in the USA

Answer 14

63% of new infections are in gay and bisexual men
25% other heterosexual contact
44% African American
10% of new infections are in young gay black men

Question 15

Ro for HIV

Answer 15

Ro

Question 16

Pathogenesis of initial HIV infection

Answer 16

1) Virus is in the mucosa
2) If there are breaks in that tissue the virus can cross into the target cells it wants to affect called the founder cells (macrophages, dendritic cells)
3) Days later there is local expansion (still susceptible to antivirals, why PEP works)
4) Drains into the lymphnodes, and propagates around the body (PEP no longer effective)

Women are more vulnerable to get HIV from Men than Men are from women

Question 17

HIV microbiology

Answer 17

ssRNA virus, two copies of the genone in the virion (so it’s diploid and those two copies are often different from one another

Question 18

Early HIV coreceptor used alongside CD4

Answer 18

CCR5 on marcophages

people with delta32 mutations of CCR5 can be HIV resistant

Question 19

Late HIV coreceptor used alongside CD4

Answer 19

CXCR4 on T cells

Question 20

Biggest change in antiviral therapy

Answer 20

when we created protease inhibitors

protease cleaves gag into its subunits MA-CA-NC

Question 21

syncytium formation

Answer 21

Env can fuse infected T cells with uninfected T cells (lethal for T cells)
creates more virulent strains

Question 22

N. gonorrhea treatment

Answer 22

ceftriaxone

Question 23

C. trachomatis treatment

Answer 23

Doxycycline

If Preggers, Peds or allergic: Erythromycin