CNS and STDs

Question 1

1. What is the reservoir for Neisseria meningitidis?
2. How is it spread?

Answer 1

1. Nasopharynx of humans only
2. Spread by respiratory transmission

Question 2

What is the characteristic structure/physiology of Neisseria meningitidis?

Answer 2

Gram negative diplococci with a LipoOligoSaccharide capsule

Question 3

1. Does Neisseria meningitidis possess pili?
2. What is the general process of a N. meningitidis infection?

Answer 3

1. Yes
2. Attach to non-cilia columnar epithelia → Internalized into phagocytic vacuoles → Transcytosis to subepithelial space → LOS induces vascular damage, vessel inflammation, thrombosis

Question 4

1. What does an acute *N. meningitidis *infection look like?
2. What does infantile meningitis look like?
3. How is N. meningitidis infection diagnosed?

Answer 4

1. Abrupt and insidious onset w/ symptoms of a general meningitis (Nuchal rigidity etc.)
2. Irritable, Decreased PO, Seizures, Disturbed tone, Coma
3. Oxidase positive, Gram negative diplococci gram stain of CSF.

Question 5

1. What is the demographic with the highest incidence of N. meningitidis infection?

Answer 5

1. School-age children and young adults

Question 6

1. How many and which serogroups does the N. meningitidis vaccine cover?
2. What is added to make the vaccine effective?

Answer 6

1. It is tetravalent for A, C, Y, W135
2. It is a conjugate vaccine with Diptheria toxin.

Question 7

What is the treatment for N. meningitidis infection?

Answer 7

Cefotaxime
Ceftriaxone
Penicillin G

Question 8

What is used for prophylaxis if someone is exposed to the disease for >8 hours?

Answer 8

Rifampin
Cipro
Ceftriaxone

Question 9

At what age are neonates most at risk/susceptible to N. meningitidis?

Answer 9

6 to 24 months

Question 10

What two sugars does N. meningitidis metabolize?

Answer 10

Maltose and Glucose which can be remembered because meningitis has an M and a G in it.

Question 11

1. What is different about the structure of N. gonorrhea compared to N. meningitidis?
2. How are they similar in structure?

Answer 11

1. It has NO polysaccharide capsule
2. They both possess pili

Question 12

What does N. gonorrhea express that interferes with neutrophil degranulation and resists complement?

Answer 12

PorB

Question 13

1. What do Opa proteins do to promote N. gonorrhea virulence?
2. What portion of N. gonorrhea causes cellular damage?

Answer 13

1. They mediate binding to non-ciliated epithelial cells
2. Core LOS damages urethral and vaginal epithelium

Question 14

How does N. gonorrhea escape antibodies produced by the immune system?

Answer 14

1. Pili frequently alter epitopes
2. PorB has significant serological variation

Question 15

What organism is responsible for the presence of Oxidase positive, gram negative diplococci within PMNLs?

Answer 15

Neisseria gonorrhea

Question 16

What are the special needs of N. gonorrhea when attempting to culture?

Answer 16

It requires a complex medium (chocolate agar) and is sensitive to cold

Question 17

Why isn’t there a vaccine for gonorrhea?

Answer 17

No capsule + High variability

Question 18

1. What age group is the peak incidence for gonorrhea?
2. What is the major reservoir?
3. Are symptoms more common in women or men?

Answer 18

1. 15-24 year olds
2. Asymptomatic individuals
3. Men

Question 19

1. How is Chlamydia trachomatis structure similar/different than N. gonorrhea?
2. What implication does this have on clinical treatment?

Answer 19

1. It is gram negative but does not have a PDG cell wall
2. Beta lactam antibiotics won’t work

Question 20

There are two structural forms for Chlamydia trachomatis, the elementary body and the reticulate body. What is the purpose of each?

Answer 20

1. Elementary body is the infectious form and is environment stable.
2. Reticulate body is the replicative form, is metabolically active, and is NOT environment stable.

Question 21

1. Where does Chlamydia trachomatis replication take place?
2. *Chlamydia trachomatis *is an obligate intracellular parasite. How does it manage to survive inside of inclusion body?

Answer 21

1. Within an inclusion body.
2. It interferes with normal endocytic trafficking.

Question 22

1. How is Chlamydia trachomatis acquired?

Answer 22

1. It is acquired through abrasions or lesions at a sexual site. It attached to non-ciliated **columnar cuboidal ** or transitional epithelia cells.

Question 23

1. What is the more invasive form of Chlamydia trachomatis that can develop into proctitis in women?
2. What happens with untreated Chlamydia trachomatis?

Answer 23

1. Lymphogranuloma venereum
2. It enters a chronic ulcerative phase.

Question 24

1. How/where is a specimen collected for women concerning for Chlamydia trachomatis?
   * 2. Chlamydia trachomatis* cannot be grown in artificial media. What is the best way to test the specimen collected?

Answer 24

1. Endocervical specimen
2. Nucleic acid amplification test.

Question 25

1. What is Reiter syndrome and what organism causes it?
2. What is trachoma?

Answer 25

1. It is urethritis, conjunctivitis, polyarthritis and mucocutaneous lesions. It is caused by Chlamydia trachomatis.
2. It is keratoconjunctivitis by serotypes A,B,Ba, and C. It is endemic to everywhwere except North America and Europe.

Question 26

Who is more likely to be asymptomatic with urogenital *Chlamydia trachomatis *infection, Men or Women?

Answer 26

Women are asymptomatic 80%

Men are asymptomatic 25%

Question 27

What antibiotics are used for Chlamydia trachomatis?

Answer 27

Doxycycline, Erythromycin, or Azythromycin

Question 28

Chlamydia psittaci is primarily an infection of birds and poultry, how can humans acquire it and what kind of illness does it create?

Answer 28

Inhalation of desicated feces particles which causes a viral-like atypical pneumonia.