STI

Question 1

what is the causative agent of gonorrhea?

Answer 1

neisseria gonorrhoeae (gonococcus)

Question 2

what kind of bacteria is the causative agent of gonorrhea?

Answer 2

gram-negative diplococcus (coffee bean shape)

Question 3

is gonococcus fastidious? how does collecting samples for testing go?

Answer 3

yes they are, they do not grow very well in culture and they’re susceptible to drying
- require transport medium for culture, regular blood agar will not work it needs enriched ingredients
- will die if dried or delayed

Question 4

what is a sign of gonorrhea?

Answer 4

gonorrheal discharge in the cervix or urethra

Question 5

is gonorrhea increasing? who is it most common amongst? transmitted how?

Answer 5

incidence dropped in 1990s, now increasing across Canada
- most common in 20-25 age group
- transmitted through contact of mucous membranes (sexually or perinatally)

Question 6

what are the main clinical manifestations of gonorrhea?

Answer 6

• mucopurulent urethritis
• mucopurulent cervicitis
• pelvic inflammatory disease
• pharyngitis (sore throat)
• conjunctivitis (pink eye)
• disseminated gonococcal infection, especially joint infection (fever, arthritis, skin lesions)
• gonorrheal ophthalmia neonatorum (neonates)

Question 7

what is gonorrheal ophthalmia neonatorum ?

Answer 7

Gonorrheal ophthalmia neonatorum is a severe eye infection in newborns caused by transmission of the Neisseria gonorrhoeae bacteria from an infected mother during birth
- Symptoms include red, swollen eyes with pus or purulent discharge, which can rapidly lead to corneal damage, ulceration, and permanent blindness if not treated promptly

Question 8

how does disseminated gonococcal infection happen?

Answer 8

if it goes untreated for long enough, it becomes disseminated through their body so they can become bacteria in their blood that can set up infections elsewhere ex. joints

Question 9

what are the two mechanisms used for diagnosing gonorrhea and chlamydia?

Answer 9

1. Nucleic acid amplification testing (NAAT)
   - includes PCR testing
   - can detect by urine sample
   - done on a machine called panther, which can also detect dead organisms
2. culture of urethral or cervical swabs
   - less sensitive, but very specific
   - resistance is becoming a problem

Question 10

what is the go to treatment for gonorrhea?

Answer 10

cefixime (oral) or ceftriaxone (intramuscular, most common) combined with one does of azithromycin (athrizo is for possible chlamydia co-infection)

Question 11

what did they use to prescribe for gonorrhea?

Answer 11

ciprofloxacin - but resistance is now common
resistance is appearing worldwide to cefixime and ceftriaxone

Question 12

what is the causative agent for chlamydia?

Answer 12

chlamydia trachomatis
- different serotypes exist

Question 13

certain types of chlamydia trachomatis can cause… but…

Answer 13

can cause LGV (lymphogranuloma venereum) but these types are not endemic in Canada

Question 14

some types of chlamydia can cause eye disease…

Answer 14

called trachoma, a type of severe conjunctivitis (found in tropics)
- can happen among newborns

Question 15

chlamydia trachomatis is what kind of bacteria?

Answer 15

obligate intracellular bacteria devoid of a cell wall (cannot be gram-stained)
- atypical organism

Question 16

what is the culture like needed for testing chlamydia?

Answer 16

• cannot be grown on artificial media, requires culture in cultured cells (expensive)
• detected by molecular amplification testing routinely

Question 17

chlamydia has two alternating forms:

Answer 17

1. reticulate body: actively replicating form found within cells
2. elementary body: inert infectious form found on the surface of cells, invades cells. transmitted form

Question 18

when the RB or EB enter cells what do they become?

Answer 18

RB: when mature it causes cell rupture and fragments into many elementary bodies
EB: on entering cells, develops into the reticulate body

Question 19

what cells does chlamydia infect?

Answer 19

urethral, cervical, and conjunctival epithelial cells

Question 20

what form of chlamydia is the sexually transmitted form?

Answer 20

elementary body

Question 21

how common is chlamydia? transmitted how? most common amongst who?

Answer 21

• one of the most common STIs
• transmitted through sexual contact or perinatally, direct contact to conjunctiva
• most common in 15-25 age group
• asymptomatic carriers are common
• incidence increases as number of partners increases

Question 22

what are the clinical manifestations of chlamydia?

Answer 22

• nongonococcal mucopurulent and cervicitis (drainage from urethra)
• epididymitis
• pelvic inflammatory disease
• proctitis (inflammation of the rectum and anus)
• reactive arthritis, urethritis (UTI)
• conjunctivitis (especially in neonates) and trachoma

Question 23

what are complications of pelvic inflammatory disease?

Answer 23

ectopic pregnancy and sterility secondary to scarring

Question 24

how are swabs taken for chlamydia?

Answer 24

men:
- urine swabs
- urethral swabs
women:
- self-taken vaginal swabs
- specimen of choice
- urine (not common)
- endocervical swabs (not common)

Question 25

what is treatment for chlamydia?

Answer 25

doxycycline, azithromycin, erythromycin

Question 26

what is the causative bacteria of syphilis?

Answer 26

treponema pallidum, a tightly coiled spirochaete

Question 27

what is difficult about the syphilis bacteria?

Answer 27

it is not easily cultured in the lab and it is too fine to gram stain so darkfield microscopy is used

Question 28

most common in who? how is it transmitted?

Answer 28

not very common in general but getting more prevalent - most common in men with multiple male partners mainly transmitted through sexual contact, can transmit through birth

Question 29

what are the five clinical manifestations of the syphilis bacteria?

Answer 29

1. primary syphilis (localized) 2. secondary syphilis (systemic) 3. latent infection (asymptomatic) 4. tertiary syphilis (late) 5. congenital

Question 30

primary syphilis?

Answer 30

presents 1-4 weeks post contact - produces a chancre (painless ulceration) - heals spontaneously in weeks

Question 31

secondary syphilis?

Answer 31

bacteria has transmitted through the body into the blood - full body skin rash, flu like illness, lymphadenopathy (swollen lymph nodes)

Question 32

latent infection?

Answer 32

have it, but no symptoms usually happens instead of secondary syphilis

Question 33

tertiary syphilis?

Answer 33

- cardiovascular (heart failure) and neurological (dementia, seizures, paralysis) - gumma (masses on skin surface or in organs)

Question 34

congenital syphilis?

Answer 34

bone, teeth, and brain damage - most prevalent in children born with syphilis

Question 35

when is dark field microscopy used for diagnosing syphilis?

Answer 35

in the primary disease only, high volume areas - used on primary chancre

Question 36

serology is the main route to diagnosis, what are the two tests?

Answer 36

1. nonspecific test (non treponemal test) - VDRL, RPR (rapid plasma reagin) cheap but can also give false positives 2. specific test - enzyme immunoassay (EIA) is often used first - TRPA confirmatory these are used with non specific tests

Question 37

what is the treatment for syphilis?

Answer 37

1. penicillin - doxycycline is used as alternative if allergy - longer treatment needed if CNS involvement - HIV is a common co-infection

Question 38

what is the bacteria like that causes genital herpes?

Answer 38

neurotropic, invades nerves and becomes dormant within them, regrowth gives reactivation of infection

Question 39

how common is herpes? amongst who?

Answer 39

primary, laten, and recurrent infection - occurs in all population groups - prevalence of antibody increases with age and correlates too number of partners

Question 40

clinical presentations of herpes?

Answer 40

1. primary infection - fever, headache - painful lesions on genitalia - unusual discharge - tender nodes 2. latent - shedding of virus without any lesions

Question 41

reocurrance and congenital of herpes

Answer 41

HSV-2 > HSV-1 - usually less severe than primary infection - localized to genitals - 50% have prodromal symptoms (tingling, pain) congenital infection in babies especially if mother has primary infection during delivery - life threatening

Question 42

diagnosis of herpes?

Answer 42

swabs of local lesions - NAAT

Question 43

treatment of herpes?

Answer 43

antivirals - acyclovir, valacyclovir - long term prophylaxis may be necessary if breakouts are common

Question 44

genital warts is caused by

Answer 44

human papillomaviruses - certain serotypes are causative agents of cancers, oral, cervical, and anal

Question 45

what is the main symptom of HPV?

Answer 45

skin growths on genitalia, perianal area - may be asymptomatic, usually transient infection resolving in months

Question 46

what does the HPV vaccine do?

Answer 46

prevents infection by more common cancer-related types - warts can be removed by chemical means, freezing, or surgery