14 Neisseria gonorrhea & Chlamydia

Question 1

What disease is the second most commonly reported infectious disease in the US with >330,000 cases in 2012?

Answer 1

Neisseria gonorrhea

Question 2

What disease is the first most commonly reported infectious disease in the US with 1.4 million cases in 2012?

Answer 2

Chlamydia

Question 3

What is the mode of transmission for N. gonorrhea?
Environmental
Human-human
Insect-borne
Animal-human

Answer 3

Human-human ONLY

Question 4

What are the hallmark signs of N. gonorrhea?

Answer 4

Inflammation and purulent discharge from a mucosal surface

Question 5

What mucosal surfaces can be involved in a N gonorrhea infection?

Answer 5

throat, anal, eyes of infants, male urethra, female cervix mucosa

Question 6

What are the sx of gonorrhea urethritis in males?

Does the male seek treatment?

Answer 6

extensive urethral discharge
dysuria
rare complications
Yes, infected male seeks treatment 2-5 days after the sexual encounter

Question 7

What are the sx of gonorrhea infection in females (gonorrheal cervicitis)?

Answer 7

generally none - if symptoms, variable
Possibly:
abdominal pain
cervical discharge
dysuria
intermenstrual bleeding

Question 8

What is the chance of an uninfected female engaging in genital sex with an infected male becoming infected?

Answer 8

50-73%

Question 9

What is the chance of an uninfected male engaging in genital sex with an infected female becoming infected?

Answer 9

20%

Question 10

Which portion(s) of the female reproductive tract are initially infected with N. gonorrhea?

Answer 10

Only the cervix (columnar epithelial cells)

Not the vaginal mucosa

Question 11

What is the danger of untreated gonorrhea & Chlamydia in females?
Gonorrhea: What percentage of infected, untreated females have complications?

Answer 11

It ascends into the uterus and fallopian tubes (salpingitis)
PID (pelvic inflammatory disease), possibly causing fallopian tube scarring and/or persistent pelvic pain
10-20%

Question 12

Define salpingitis:

Answer 12

inflammation of the fallopian tubes

Question 13

What are the potential complications of damaged fallopian tubes?

Answer 13

infertility & ectopic pregnancy

Question 14

What can happen if N. gonorrhea enters the blood stream? (systemic infection complications)

Answer 14

septic arthritis - fever, migratory arthralgiaas, reddened pustular lesions on extremities, petechiae
gonococcal meningitis
endocarditis

Question 15

What is the most common cause of infectious arthritis in sexually active adults?

Answer 15

Septic arthritis caused by N. gonorrhea

Question 16

Who is more susceptible to systemic complications of N. gonorrhea?

Answer 16

females

patients with late complement protein deficiencies

Question 17

Define ophthalmia neonaturum:

When does it develop?

Answer 17

Purulent conjunctivitis leading to blindness if untreated

Develops 5 days after vaginal birth to a gonococcal-infected mother

Question 18

What is the prophylaxis treatment for ophthalmia neonaturum?

When is it given?

Answer 18

Eye drops of erythromycin/neomycin administered within minutes after birth

Question 19

What is happening during much of the incubation period for N. gonorrhea? How is it getting into the body? Where does it replicate?

Answer 19

Pili and other proteins allow them to adhere to non-ciliated epithelium
They trick epithelial cells to take them up into intracellular vesicles and then exit out the basolateral surface
Bacteria replicate in the sub-epithelial space

Question 20

Bacteria replicating in the sub-epithelial space elicit what response? To what part of the bacterium?

Answer 20

They elicit a characteristically exuberant PMN response in response to LOS

Question 21

What 5 virulence factors does N. gonorrhea use to survive PMN killin?

Answer 21

• Opa (opacity protein) mediates firm attachment to epithelial cells and invasion into cells
• Outer membrane porin (Por) prevents phagolysosome fusion following phagocytosis -> promoting intracellular survival
• Rmp is an outer membrane protein that blocks bactericidal antibodies directed against Por and LOS
• Other surface features block or cleave antibodies
• Iron binding systems steal iron from lactoferrin, transferrin, and hemoglobin to overcome host’s nutritional immunity

Question 22

If untreated, how long will N. gonorrhea infections persist?

Answer 22

months even after antibody titers reach high levels

Question 23

How can N. gonorrhea persist for months even with high antibody titers?

Answer 23

Antigenic diversity: has numerous strategies for hypervariability of surface proteins (e.g. 1 in 100-10,000 bacteria make a novel pilin variant -> keeps gc ahead of immune system)

Question 24

How is gonorrhea diagnosed in symptomatic males?

Answer 24

G- dipplococci observed in purulent discharge from the urethra (Gram stain)
can plate on chocolate agar for culture

Question 25

How is gonorrhea diagnosed in females?

Answer 25

Because of complex vaginal flora, requires more than Gram stain
Streak cervical specimen onto Thayer-Martin agar (chocolate agar + antibiotics that select against normal vaginal flora) & plain chocolate agar
Diagnosis made by culture of bacteria on selective media

Question 26

What is the alternative lab procedure for diagnosis of gonorrhea in males or females?

Answer 26

PCR assay that identifies gc-specific DNA

Question 27

What are the pros/cons of PCR DNA assay over culture for gonorrhea diagnosis?

Answer 27

DNA assay faster than culture
DNA assay less invasive because can be conducted from urine specimen
DNA assay able to avoid fragile gc dying during specimen transport
Downside: DNA assay has no antibiotic sensitivity determinations; culture does

Question 28

Gonorrhea treatment?

Answer 28

Penicillin no longer effective because of beta-lactamase prevalence in last 30 years
Cephalosporins (ceftriaxone - 3rd gen broad spectrum) is effective

Question 29

If gonorrhea is diagnosed and removed but the symptoms remain, what is likely the problem?

Answer 29

there was an underlying Chlamydia problem that goes undiagnosed until the gonorrhea is removed. If not treated quickly, complications can arise

Question 30

What is the antibiotic treatment of a Chalmydia infection?

Answer 30

If Chlamydia trachomatis has not been ruled out, azithromycin or doxyxycyclin is also used

Question 31

What are 4 options for gonorrhea prevention?

Answer 31

No vaccine - hypermutable surface antigens
Barrier contraception - condoms + nonoxynol-9 containing spermicide
Abstinence
Wholly monogamous relationships

Question 32

What are the lab characteristics of Chlamydia?

Answer 32

obligate intracellular parasite

non-motile G- bacteria

Question 33

Being an intracellular parasite, Chlamydia relies on host machinery for what metabolism?

Answer 33

Rely on host enzymes to provide many amino acids and other building blocks
STEAL ATP from the host cell

Question 34

What is present on the outer membrane of human-specific Chlamydia?

Answer 34

LPS and lipid A but very little to no peptidoglycan

Question 35

What is the name for the active replicating form in the Chlamydia life cycle?

Answer 35

Reticulate body (RB)

Question 36

What is the name for the inactive, non-replicating infectious form of Chlamydia?

Answer 36

Elementary body (EB)

Question 37

Does Chlamydia cause acute or chronic infections?

Answer 37

both :)

Question 38

Which is resistant to harsh conditions?
reticulate body
elementary body

Answer 38

elementary body

Question 39

Which of these species are in the genus Chlamydia and which are in Chlamydophilia?
C. trachomatis
C. psittaci
C. pneumoniae

Answer 39

Chlamydia trachomatis
Chlamydophilia psittaci
Chlamydophilia pneumoniae

Question 40

Which is responsible for STDs, conjunctivitis, lymphogranuloma venereum, trachoma, infant pneumonia?
C. trachomatis
C. psittaci
C. pneumoniae

Answer 40

C. trachomatis

Question 41

Which is responsible for bronchitis, sinusitis, and primary atypical pneumonia syndrome while also being linked to atherosclerosis?
C. trachomatis
C. psittaci
C. pneumoniae

Answer 41

C. pneumoniae

Question 42

Which is responsible for severe influenza-like disease from psittacine birds (ornithosis or parrot fever)?
C. trachomatis
C. psittaci
C. pneumoniae

Answer 42

C. psittaci

Question 43

What is the most common bacterial sexually transmitted infection in the US and the most common cause of preventable blindness in the world?

Answer 43

C. trachomatis

Question 44

What infections are at peak incidence at ages 18-24?

Answer 44

gonorrhea & Chlamydia trachomatis

Question 45

What Chlamydia trachomatis serovars cause STDs?

Answer 45

D-K

Question 46

What is the diagnosis of nongonococcal urethritis in men? How often is it asymptomatic?

Answer 46

lack of pink diplococcic in Gram stain of exudate

Asymptomatic in at least 1/3 of males

Question 47

How does postgonococcal urethritis develop? When?

Answer 47

In men who are treated with antibiotics for diagnosed gonorrheal urethritis
2-3 weeks post-treatment of gonorrhea, Chlamydia becomes evident

Question 48

What signs/symptoms are present in mucopurulent cervicitis?

What is the complication if left unchecked?

Answer 48

No obvious symptoms
Careful speculum exam shows yellow mucopurulent discharge in 30-50% cases
Can progress to PID

Question 49

What bacterium can cause urethral infections in sexually active women, epididymitis, Reiter’s syndrome?

Answer 49

Chlamydia trachomatis

Question 50

What is epididymitis?

Answer 50

Unilateral scrotal pain, fever, epididymal tenderness or swelling
Most common local complication of Chlamydia trachomatis infection

Question 51

What is Reiter’s syndrome?

Answer 51

immune mediated disease: 3 combined conditions:

• urethritis
• arthritis
• conjunctivitis

Question 52

What infection is found in newborns delivered vaginally by C. trachomatis-infected mothers?

Answer 52

conjunctivitis or TRIC (trachoma inclusion conjunctivitis) - profuse mucopurulent discharge
followed by neonatal afebrile pneumonia

Question 53

How is adult inclusion conjunctivitis contracted by adults? Severity?

Answer 53

transmitted thru hand-to-eye spread of infected genital secretions (Chlamydia trachomatis)
rarely leads to blindness (milder than trachoma)

Question 54

Define lymphogranuloma venereum:

Answer 54

rare disease in US
transient, painless papule or vesicle on any part of genitals; may rarely ulcerate. painful, multiocular suppurative lymphadenopathy, fever, headaches, conjunctivitis, skin rashes, nausea vomiting

Question 55

What is the treatment for Chlamydia trachomatis infection?

Answer 55

little protective immunity
no acquired antibiotic resistance
most infections treated with tetracycline/doxycycline or macrolides (erythromycin for neonatal infections or azithromycin)

Question 56

What are the recommendations on intercourse while treating C. trachomatis?

Answer 56

treatment of sexual partner key

abstain from intercourse for 7 days after therapy has begun

Question 57

What is the SAFE strategy?

Answer 57

Surgery for deformed eyelids, Azithromycin; Face washing and Environmental improvements
Blindness prevention public health effort

Question 58

Chlamydophila pneumonia diagnosis:

treatment?

Answer 58

difficult, tissue culture not routinely used
retrospective diagnosis
treatment: tetracycline or erythromycin

Question 59

Who are most at risk for a C. psittaci infection?

Mode of transmission

Answer 59

people who work with birds or at a poultry slaughter house

Generally acquired from birds via respiratory route

Question 60

Psittacosis is:

Answer 60

pneumonia with systemic manifestations (fever, headache, etc); spread to liver, spleen, heart, kidney