Microbiology of your junk Flashcards Preview

Module 6: Repro/Endocrine > Microbiology of your junk > Flashcards

Flashcards in Microbiology of your junk Deck (22):
1

What are the primary non-ulcerative STIs?

N. gonorrhoeae C. trachomatis (servars D-K) Mycoplasma and Ureaplasma

2

Gram -

no detectable peptidoglycan

DNA, RNA, 70s ribosomes

Intracellular pathogen

Chlamydia trachomatis

3

Gram negative Capnophilic Pyogenic coccus

N. gonorrhoeae

4

What type of infections does N. gonorrhoeae cause?

Urethritis in men>women Cervicitis 50% asymptomatic Pharyngitis Proctitis Opthalmia neonatorum PID, Endometritis, Salpingitis Epididymitis DIG

5

Discribe the manifestations of disseminated gonococcal infection.

Dermatitis-hemorrhagic papular lesions, fingers, wrists and feet (Reactive) Arthritis-large joints, synovial fluid cultures postive in 30% Endocarditis

6

What are gonococcal virulence factors?

colonization pili - adheres to epithelium 
Fe receptors - lactoferrin, transferris, Hb
IgA1 specific protease
Opa proteins - invade epithelial cells
LOS - addition of host derived sialic acid
Porin P1A & P1B bind C4bp and FH

7

Why are repeated gonococcal infections so common?

Homologous recombination of the pilE genes with pilS loci results in 10^17 different types of pili May be immunosuppressive by inducing Th17 pathway

8

How is gonorrhea diagnosed in the laboratory?

Gram stain -95% sensitive in men, 50-70% in women PCR/DNA (NAAT) - urine or cervical discharge Culture - chocolate or thayer martin in candle jar

9

What is current treatment for gonococcal infections?

ceftriaxone with azithromycin or doxycycline

10

Symptoms of Chlamydial Urethritis/cervicitis?

Men -symptomatic discharge clear

Women -usually asymptomatic

LGV-ulcerative disease of the lymphatics

11

What can an ascending Chlamydial infections result in?

Reiter's syndrome (urethritis, conjunctivitis, polyarthritis) Epidydimitis Endometritis, salpingitis, PID

12

What is the most common form of neonatal conjunctivitis in the US?

Chlamydial conjunctivitis

13

What are elementary bodies and reticulate bodies?

EM-extracellular, infectious, metabolically inactive form of C. trach. Contains disulfide cross-linked outer membrane proteins

RB-Larger, intracellular replicative form of C. trach. Osmotically fragile

14

What is the pathogenesis of C. trachomatis?

induce acute and chronic inflammation
cytopathic effect on host cells

tissue damage (fallopian tube scarring) caused by host response

heat shock proteins may play a role

15

How is Chlamydia diagnosed?

NAAT

direct fluorsecent antibody test
Culture with MOMP-specific antibody

16

How is Chlamydia treated?

single dose of azithromycin

Tetracycline or Doxy for 7 days

LGV- doxy for 21days

Conjunctivitis- oral erythromycin

 

17

Ureaplasma urealyticum and Mycoplama genitalium account for what percent of nongonococcal urethritis cases?

20%

18

How do you diagnose Mycoplasma/Ureaplama spp.?

rule out other causes
Inoculate specail transport media (PPLO)
Colonies will appear on solid agar plates in 2-5 days

Nuc. acid and other rapid diagnostic tests in development

19

What's the most common CDC reportable STI?

Chlamydia trach.

20

How does coinfection affect HIV transmission?

Increases it
-inflammatory response brings WBCs to site of infection
-HIV viral load higher in gonorrhea secretions
-ulceritive STIs increase suceptibility 

21

Why are younger women at increased risk of Chlamydia and Gonorrhea?

Cervical ectopy

columnar epitheilium less resistant to infection

22

What is nonoxynol-9 and how does it affect STI transmission?

Spermicide
increases transmission by disrupting endothelial cells (detergent action)

inflammation brings in WBCs for HIV to infect