Bacterial STIs I

Question 1

What serotype of Chlamydia trachomatis causes blindness?

Answer 1

C. trachomatis sereotypes A, B, Ba, and C cause Trachoma (blindnes).

This is the leading worldwide cause of preventable blindness

Question 2

What serotype of c. trachomatis causes Urogenital tract disease?

Answer 2

D-K

Question 3

C. trachomatis is unable to produce what?

Answer 3

C. trachomatis is unable to produce ATP- therefore it is an obligate intracellular parasite

Question 4

What two forms can C. trachomatis exist in?

Answer 4

C. trachomatis can exist as

Elementary body: infectious form

Reticulate body: noninfectious form

Question 5

what type of cells do C. trachomatis preferentially attach to?

Answer 5

C. trachomatis preferentially attaches to columnar epithelial cells

Question 6

what form of C. trachomatis is metabolically active?

Answer 6

Reticulate bodies are the metabolically active form of C. trachomatis

Question 7

what form of C. trachomatis is:
resistant to harsh environmental factors

has a double layer outer membrane

and has a central, dense core with a cytoplasmic membrane

Answer 7

Elementary body

it is the metabolically inactive form of C. trachomatis

Question 8

C. trachomatis can initiate the reactive arthritis syndrome known as what?

Answer 8

Reiter syndrome

“can’t see, can’t pee, can’t climb a tree”

Question 9

How do we identify C. trachomatis?

Answer 9

Nucleic acid amplification test

EIA test

chlamydial inclusions in conjunctival scrapings by Giemsa stain or DFA

Culture with isolation in McCoy cells

Question 10

What type of stain do you use for C. trachomatis?

Answer 10

Giemsa

or

Direct fluorscent Ab stain (DFA)

Question 11

S/S:

purulent discharge

dysuria

PID

can cause neonatal eye infection

Answer 11

Neisseria gonorrhoeae

Question 12

Buzzwords:

purulent discharge

no protective immunity

IgA protease

Lipooligosaccharide

Answer 12

Neisseria gonorrhoeae

Question 13

what is the morphology of Neisseria gonorrhoeae?

Answer 13

Neisseria gonorrhoeae is a gram (-) diplococci

Question 14

what type of cells does Neisseria gonorrhoeae infect?

Answer 14

Neisseria gonorrhoeae infects polymorphonuclear leukocytes

The bacteria prevents the phagocyte and lysosome from fusing, so the lysosomes are rendered ineffective

Question 15

Neisseria gonorrhoeae

What is the function of:

OMP I

OMP II

OMP III

Answer 15

Neisseria gonorrhoeae

1. OMP 1: functions as a porin protein along with OMP III to resist phagolysosome formation
2. OMP II: function is for attachment to cells
3. OMP III: reduction-modifiable proteins protect surface antigens from antibodies

Question 16

Other virulence factors of Neisseria gonorrhoeae include:

Answer 16

IgA1 protease

Transferrin, lactoferrin

Pili (attachment to specific sites on mucosal surfaces)

Lipooligosaccharide that leads to inflammation and tissue damage

Question 17

Diagnosis of Neisseria gonorrhoeae can be made by:

Answer 17

1. culture on both nonselective (chocolate blood agar) and selective enriched media (Thayer-Martin medium)
2. PCR
3. Gram stain with intracellular G-neg diplococci
   
   1. females require culture with isolation to verify the dx

Question 18

where should specimens be collected for diagnosis of Neisseria gonorrhoeae?

Answer 18

specimens should be collected from the

urethra of male

cervix of femals

Question 19

Neisseria gonorrhoeae

treatment

Answer 19

dual therapy:

injectable ceftriaxone and oral azithromycin

the azithromycin is because the chance of a coinfection with chlamyida is high