STI's

Question 1

what causes Gonorrhea

Answer 1

Neisseria gonorrhoeae (“gonococcus”)

Question 2

Describe the characteristics of Neisseria gonorrhoeae (what causes gonorrhoea)

Answer 2

1. Gram-negative diplococcus (coffee bean shape)
2. Fastidious, and susceptible to drying
   requires transport medium for culture
3. Requires enriched medium and CO2 .
   Dies if dried or delaye

Question 3

Do you use cultures to detect gonorrhoea

Answer 3

no, molecular methods are commonly used

Question 4

Describe how Gonorrheae is clinically represented

Answer 4

1. Increasing across Canada
2. Most common in 20-25y age group
3. Transmitted through contact of mucous membranes
   (sexually or perinatally)

Question 5

what are the clinical manifestations of gonorrhoea

Answer 5

1. mucopurulent urethritis (Infection of the urethra that causes pus-filled discharge and sometimes painful urination)
2. mucopurulent cervicitis (Infection of the cervix causing pus-like discharge, sometimes with bleeding or pain)
3. pelvic inflammatory disease (Infection that spreads from the cervix/uterus to the uterus, fallopian tubes, or ovaries, causing pain, fever, and sometimes long-term complications)
4. pharyngitis (Infection or inflammation of the throat, causing sore throat or discomfort)
   5.conjunctivitis (Red, swollen, and often pus-filled infection of the eye (sometimes called “pink eye”))
5. disseminated gonococcal infection, especially joints (Gonorrhea bacteria spread through the bloodstream, often affecting joints, skin, and sometimes organs)
6. gonorrheal ophthalmia neonatorum (neonates) (Eye infection in newborns caused by gonorrhea, usually picked up during birth, can lead to blindness if untreated)

Question 6

How do you diagnose gonorrhoea

Answer 6

1. PCR (looking for organism DNA) though NAAT, Nucleic Acid Amplification Testing
2. Culture of urethral or cervical swabs

Question 7

Describe the difference between culture and PCR for Gonorrhea

Answer 7

1. PCR/NAAT =
   a) Several variations are commercially available
   b) More sensitive than culture, as molecular methods can also detect dead organisms
   c) Can detect from urine sample (EASY!)!
2. Culture of urethral or cervical swabs
   a) Less sensitive, but very specific
   b) Important for susceptibility
   testing for surveillance
   c) Resistance is becoming a
   problem, treatment failures
   increasing

Question 8

Describe how you treat Gonorrhea

Answer 8

1. Ceftriaxone (intramuscular injection) combined with azithromycin or
   doxycycline (for possible Chlamydia co-infection)
2. Ciprofloxacin resistance now common
3. Increasing resistance worldwide
   a) Resistance now appearing to ceftriaxone!
4. Contact tracing by Public Health to limit spread

Question 9

What is one of the most common STI’s

Answer 9

Chlamydia

Question 10

Describe how Chlamydia is clinically represented

Answer 10

1. Transmitted through sexual contact or perinatally, direct contact to conjunctiva
2. Most common in 15-25 age group, females tend to be younger than males
3. Asymptomatic carriers - common
4. Incidence increases as number of partners increases

Question 11

what is the causative agent of Chlamydia

Answer 11

Chlamydia trachomatis

Question 12

what can chlamydia also cause

Answer 12

1. Certain types cause
   lymphogranuloma venereum (LGV) but these types are not endemic in Canada
2. Some types cause eye disease (trachoma) a type of severe conjunctivitis (found in tropics)

Question 13

Describe the characteristics of Chlamydia trachomatis

Answer 13

1. intracellular bacteria without a cell wall (cannot be Gram-stained)
   –2. Cannot be grown on lab media, requires living
   animal cells (expensive, labor intensive)
2. Detected by molecular amplification testing

Question 14

Describe the chlamydia lifecycle

Answer 14

1. Reticulate body:
2. elementary body:
   a) inert infectious form found on the surface of cells, invades cells. Transmitted form.
   On entering cells, develops into
   the reticulate body
   * Infects urethral, cervical, and
   conjunctival epithelial cells

Question 15

Describe the elementary body of chlamydia

Answer 15

1. (takes place first) inert infectious
   form found on the surface of cells, invades cells. Transmitted form.
2. On entering cells, develops into the reticulate body
3. Infects urethral, cervical, and conjunctival epithelial cells

Question 16

Describe the reticulate body of chlamydia

Answer 16

1. actively replicating form found within cells
2. When mature, it causes cell
   rupture and fragments into many elementary bodies

Question 17

Describe the Chlamydia clinical manifestations

Answer 17

1. Mucopurulent urethritis and cervicitis
2. Epididymitis
3. Pelvic inflammatory disease (PID)
4. Complications include ectopic pregnancy, and sterility secondary to scarring
5. Proctitis
6. Reactive arthritis (formerly, Reiter’s syndrome):
   urethritis, conjunctivitis, and arthritis
7. Conjunctivitis (especially in neonates) and trachoma
   (severe form in tropics)
   Chlamydial conjunctivitis

Question 18

How do you take specimens samples to test for chlamydia for males

Answer 18

Penises:
* Urine samples!
* Urethral swabs

Question 19

How do you take specimens samples to test for chlamydia for women

Answer 19

Vaginas:
1. Self-taken vaginal swabs!
a) Specimen of choice for ease and sensitivity,
2. Urine (second-best sample)
3. Endocervical swabs (requires speculum exam)
– not frequently required now!

Question 20

How do you diagnosis chlamydia

Answer 20

Nucleic acid amplification test (NAAT) = PCR
– Various methods are commercially available

Question 21

How do you treat chlamydia

Answer 21

1. Azithromycin or doxycycline
2. contact tracing by Public Health

Question 22

what is the Causative agent of syphilis

Answer 22

Treponema pallidum

Question 23

Describe the characteristics of Treponema pallidum

Answer 23

1. Tightly coiled spirochaete
2. Not easily cultured in the lab
3. Too fine to gram stain, so we use “darkfield microscopy” (reflected light off the organism)
4. Increasing prevalence since 2000
   a) Esp. men with multiple/anonymous male partners
5. Transmission is through sexual contact or
   transplacental (to the fetus)
   Darkfield Microscopy

Question 24

describe Primary syphilis (localized)

Answer 24

1. Presents 1-4 weeks post infectious contact
2. Produces a chancre (painless ulceration)
3. Heals spontaneously within weeks

Question 25

describe Secondary syphilis (systemic)

Answer 25

1. Skin rash, “’flu like illness”, lymphadenopathy

Question 26

describe Latent infection of syphilis

Answer 26

asymptomatic

Question 27

describe Tertiary syphilis (late)

Answer 27

1. Cardiovascular (heart failure) and neurological (dementia, seizures, paralysis) 2. Gumma (late cutaneous, bony, or visceral masses)

Question 28

describe Congenital

Answer 28

bone, teeth, brain damage from syphilis

Question 29

How do you diagnosis syphilis

Answer 29

1. Nonspecific tests (Non treponemal tests) a) VDRL (Venereal Disease Research Laboratory) – mainly for CSF b) RPR (Rapid Plasma Reagin) b.1) follow titre after treatment 2. Specific tests (Treponemal tests) a) Enzyme Immunoassay (EIA) is often used as a first test b) TPPA (T. pallidum particle agglutination test) confirmatory

Question 30

How do you treat syphilis

Answer 30

1. Penicillin is treatment of choice a) Amount and duration dependent on stage of infection b) Titres of RPR can be followed for response 2. Longer treatment if CNS involvement a) Follow RPR titres to show response 3. HIV is a common co-infection (therefore, test!) 4. Contact tracing by Public Health

Question 31

what is the Causative agent of genital herpes

Answer 31

Herpes simplex virus (HSV) type 1 or 2

Question 32

Describe the characteristics of Herpes simplex virus (HSV) type 1 or 2

Answer 32

1. Linear double-stranded DNA virus a) Neurotropic - invades nerves and becomes dormant (latent) within them, regrowth gives reactivation of infection 2. Primary, latent, and recurrent infection 3. Occurs in all population groups 4. Prevalence of antibody increases with age and correlates with number of partners 5. Seroprevalence studies of HSV-2: 20-80% have antibodies 6. Transmitted through close contact with person shedding virus

Question 33

Describe the primary infection of genital herpes

Answer 33

1. fever, headache, malaise, myalgia 2. painful lesions on genitalia 3. dysuria (males: 44%, females: 88%) 4. vaginal or urethral discharge 5. tender inguinal adenopathy (nodes)

Question 34

describe latent genital herpes

Answer 34

shedding of virus without any lesions

Question 35

Describe Recurrent infection of genital herpes

Answer 35

1. Usually much less severe than primary infection 2. usually localized to genital area 3. 50% have prodromal symptoms (tingling, pain)

Question 36

describe Congenital infection in babies

Answer 36

Newborns can get genital herpes from a mother with a first-time infection at delivery, which may be localized (skin, eyes, mouth), affect the CNS (brain and spinal cord), or be disseminated (multiple organs) and can be life-threatening.

Question 37

How do you diagnose genital herpes

Answer 37

1. Swabs of local lesions a) Nucleic acid amplification test (NAAT) b) culture on cells (less sensitive, laborious) 2. Serology (blood test) is not useful for diagnosis = most are pos

Question 38

How do you treat genital herpes

Answer 38

1. antivirals (acyclovir, valaciclovir) 2. long term prophylaxis may be necessary in frequently recurrent disease

Question 39

What is the Causative agent genital warts

Answer 39

human papillomaviruses

Question 40

describe the characteristics of human papillomaviruses

Answer 40

1.Many serotypes 2. Some at non-genital body sites (not all are STIs) 3. Some serotypes lead to cancer (cervical, anal, oral)

Question 41

describe how genital warts are clinically presented

Answer 41

1. Transmission by direct sexual contact 2. Skin growths on genitalia, perianal area, a) May be asymptomatic b) Usually transient infection, resolving in months

Question 42

describe the treatment of genital warts

Answer 42

1. Warts can be removed by chemical, freezing, or surgery 2. Vaccine prevents infection by more common cancer- related types