Week 4: Sexually Transmitted Infections Flashcards
Question

C. They don’t survive long without warmth and moisture
Features of sexually transmitted diseases

Epidemiology of STDs

Most common STD
Chlamydia
Why are STDs prevalence increasing
?
Chlamydia clinical manifestations
8 listed
- Urethritis
- Cervicitis
- PID
- Epididymitis
- Proctitis
- Conjunctivitis, Trachoma
- Neonatal pneumonia and conjunctivitis
- Reactive arthritis
Gonorrhea clinical manifestations
8 listed
- Urethritis
- Cervicitis
- PID
- Epididymitis
- Proctitis
- Conjunctivitis
- Neonatal conjunctivitis
- Disseminated infection
Why are the clinical manifestations of Chlamydia and Gonorrhea similar?
They both adhere to columnar epithelium
What is Urethritis?
- infection of urethra (not urinary tract infection)
Gonococcal urethritis or cervicitis incubation period
3 - 7 days
Urethritis signs & symptoms
- dysuria
- purulent discharge
Cervicitis signs and symptoms
- Dysuria (pain with urination)
- Purulent discharge
Gonococcal urethritis and cervicitis

Gonorrhea pathogen
Neisseria gonorrheae
Neisseria gonorrheae classification
Gram-negative diplococci (not truly intracellular)
Neisseria gonorrheae tropism
Adhere to columnar epithelium
- Cervix
- Urethra
- Rectum
- Eye
- Throat
Neisseria gonorrheae discharge
Vigorously purulent response
Neisseria gonorrheae immune response
- Vigorous purulent discharge
- Phagocytosed by WBCs
- Pili are antigenically variable
Examples of diplococci
- Neisseria gonorrheae
- Neisseria meningitidis
- Moraxella sp
- etc.
Gram-stain of Neisseria gonorrheae
gram-negative diplococci (pink)
How is gonorrhea diagnosed?
- Gram stain - gram-negative diplococci
- Culture media chocolate agar in high-CO2 atmosphere
- Nucleic acid amplification
Gonorrhea culture details
Chocolate agar in high CO2 atmosphere
Gonorrhea nucleic acid amplification from where?
- Urethra
- Cervix
- Throat
- Rectal
- Urine
- Vaginal
Gonorrhea evolution of resistance
- has acquired multiple plasmid and chromosomal resistance mutations
- Becoming resistant to a lot of conventional antibiotics

Resistance tracking of Neisseria gonorrheae

First-line treatment for gonorrhea
Ceftriaxone
or
Cefixime
Neisseria gonorrheae susceptibility patterns

Recommended treatment for Gonorrhea
Ceftriaxone and Azithromycin

Ceftriaxone method of use
IM
Ceftriaxone drug class
3rd generation cefalosporin
Considerations of gonorrhea treatment
6 listed
- Be sure the patient is treated correctly
- Be sure the partner is treated
- All abstain from sex for 7 days
- Report case to DOH
- Educate patient
- Promote development of new drugs
Question

D. the surface antigens mutate frequently (surface pili proteins are antigenically variable)
Chlamydia pathogen
Chlamydia trachomatis
Chlamydia trachomatis classification
Obligate intracellular bacterium
Chlamydia trachomatis tropism
Adhere to columnar epithelium cells
Chlamydia trachomatis gram stain
Outr membrane is like gram-negative bacteria but does NOT gram stain
Chlamydia trachomatis features of intracellular infection
- Doesn’t make its own ATP so it uses host cell ATP
- Cytopathic effect: cytoplasmic inclusion bodies
Chlamydia trachomatis culture
Culture requires Eukaryotic cell line so they are rarely done
Memory immune response and Chlamydia trachomatis
Immunity does not protect against reinfection
Describe the life cycle of Chlamydia trachomatis
Slower life-cycle so it requires a longer duration of anti-biotic
Have 2 different forms
Start out as Elementary bodies (more hardy survive in the environment) where they stick on columnar epithelial cell and enter the cell and form Reticulate bodies and replicate and form inclusion bodies and continue replicating until cell lysis and release of more chlamydia in the Elementary body form to infect more cells

Chlamydia and gonorrhea are most common in what age group?
- young people
- more common in women

Chlamydial urethritis incubation
7 - 21 days
Chlamydial urethritis signs & symptoms
- Dysuria (pain while urinating)
- A discharge which is often clear or scant
Chlamydial urethritis gram stain
white cells, no organisms seen
Chlamydial urethritis vs Gonorrhea urethritis
Gonorrhea is often more inflammatory and produces a purulent discharge while Chlamydia is less inflammatory and produces a clear or scant discharge
Chlamydial Cervicitis incubation
7-21 days
Chlamydial Cervicitis signs & symptoms
- Dysuria (pain while urinating)
- A discharge which is often clear or scant
Chlamydial Cervicitis gram stain
white cells, no organisms
Chlamydial Cervicitis vs gonorrhea cervicitis
Gonorrhea is often more inflammatory and produces a purulent discharge while Chlamydia is often less inflammatory and produces a clear or scant discharge
Pictures of Chlamydial urethritis or Cervicitis

PID AKA
Pelvic inflammatory disease
PID caused by Chlamydia or Gonorrhea
Chlamydia and gonorrhea start in the cervix and can progress if not treated up to the uterus and fallopian tubes where there is also columnar epithelium and cause a lot of inflammation and adhesions which can cause infertility, chronic pelvic pain, ectopic pregnancies (fallopian tube damage)

Complications of Chlamydia in women AND Gonorrhea

What is the most common presentation of chlamydia?
Absolutely no symptoms
How is Chlamydia diagnosed
Antigen detection methods
DNA probe
Nucleic acid amplification (NAAT)

Tissue culture of Chlamydia
- Expensive
- insensitive
Chlamydia Antigen Detection Methods
Insensitive
Chlamydia DNA probe
more sensitive
Test of choice for Chlamydia
NAAT (Nucleic Acid Amplification)
Chlamydia NAAT
- most sensitive
can do on
- urine
- anal swab
- cervix
- throat
- self-collected
Chlamydia screening parameters

Chlamydia and pregnancy
Conjunctivitis and pneumonia in neonates
Gonorrhea and pregnancy
Conjunctivitis
When is Chlamydia and Gonorrhea transmitted during pregnancy?
Transmitted at the time of delivery
Pregnant women and STD screening
SCREEN ALL PREGNANT WOMEN!
Chlamydia treatment
want something that gets into cells and has a long half-life
(Tetracycline, newer Doxycyline)
Azithromycin
Unique syndromes associated with Gonorrhea
- Disseminated gonococcal infection
- Bacteremia
- Skin Pustules
- Septic Arthritis
- Tenosynovitis
Unique syndromes associated with Chlamydia
Reactive arthritis
- arthritis
- Skin lesions
- Dysuria
- Eye problems
Differential Diagnoses of Genital ulcers
STIs
- Herpes Simplex
- Syphilis (Treponema pallidum)
- Chancroid (Hemophilus ducreyi)
Autoimmune
- Behcet’s
- Reactive arthritis (circinate balanitis)
Drug toxicity
- Fixed drug eruption
Other infectious and non-infectious conditions
Herpes Simplex Virus classification
Enveloped, double-stranded DNA virus (susceptible to soap and water (lipid envelope))
Type 1 Herpes Simplex virus
Usually oral
Type 2 Herpes Simplex virus
usually genital
Prevalence of HSV-2
- 17% of US adults
- Most who have it don’t know they have it
Herpes simplex virus duration of infection
Latent in neurons, reactivates periodically with or without symptoms
Herpes is forever
How can herpes simplex virus be transmitted?
can be transmitted from symptomatic sores or can even be transmitted by asymptomatic shedding
Herpes simplex virus severity
- Nuisance for most people giving them a couple of sores every couple of months
- Can be serious in immunosuppressed or neonates - transmitted at time of delivery can be very bad or lethal (however neonatal herpes infections are very rare)
Vaccine for Herpes
No vaccine yet
Treatment of Herpes Simplex Virus
- Acyclovir
- Valacyclovir
- Famciclovir
episodically for outbreaks or daily for suppression
Pictures of Genital HSV

Syphilis pathogen
Treponema pallidum
Treponema pallidum causes
Syphilis
Treponema pallidum family
Spirochete family
(others in family: Borrelia, Leptospira)
Treponema pallidum classification
- too small for light microscopy
Treponema pallidum culture
- Cannot grow in vitro
- Can inoculate into mammals for research
Diagnosis of Treponema pallidum
Direct visualization by special staining
Serology: Can be challenging to interpret
Treponema pallidum treatment
curable with penicillin
Syphilis prevalence
Was very common around 1900s but it is increasing again
Syphilis serology

Once you have had syphilis what antibody do you have
Always have Treponemal antibody if you’ve had syphilis
Categories of syphilis serology tests
- Nontreponemal (antibodies against self as a result of syphilis infection)
- Treponemal
Characteristics of nontreponemal syphilis serology
- RPR, VDRL
- Quantitative
- Titers go down with treatment
- False positives and negatives
Characteristics of treponemal syphilis serology
- TPPA, MHA-TP, FTA
- Qualitative
- Stays positive for life after an infection
- More specific than nontreponemal
False positives of nontreponemal Ab tests can be related to
other autoimmune antibodies causing a false positive for syphilis
Rates of primary and secondary syphilis

Describe the distribution of syphilis

How does syphilis get into the body
The delicate spirochetes can enter the body if there is cracked skin or microabrasions, or if they get through columnar epithelium
Events of syphilis infection
- immediately after syphilis enters the body you will get an immune response causing a local ulceration (Chancre)
- After that they can enter lymph nodes which can cause local lymphadenopathy but from the lymphatic system can distribute throughout the body
Syphilis staging
- Primary
- Secondary
- Latent
- Tertiary
- Neurosyphilis
- Congenital syphilis
When would a syphilis infection be staged as primary
2-3 weeks after infection
When would a syphilis infection be staged as secondary
6-12 weeks
When would a syphilis infection be staged as latent
where there is a positive blood test so the patient is infected but there are no current signs or symptoms
When would a syphilis infection be staged as tertiary
sometime after 12 weeks
Describe the signs and symptoms of primary syphilis
- Chancre at entry site
- regional lymphadenopathy

what is this?

Chancre (syphilis)
Serology of primary syphilis
serology may not yet be positive
Signs & symptoms of secondary syphilis
- Rash
- joint pain
- hepatitis
- general lymphadenopathy
- etc
Signs & symptoms of latent syphilis
Positive blood test so patient is infected but there are no signs & symptoms
Signs & symptoms of tertiary syphilis
- CNS damage
- Aorititis
- gumma
- other late sequelae
When does neurosyphilis occur?
CNS infection can happen at ANY stage of syphilis
How is congenital syphilis transmitted from mother to baby
Passed through the placenta
Primary chancre
usually painless

Rash of secondary syphilis
can be anywhere and can be highly variable but this rash can also go on the “palms and soles”

Condyloma lata
secondary syphilis

Patchy alopecia
secondary syphilis

Mucous patches
Secondary syphilis

Signs & symptoms of congenital syphilis
- Miscarriage
- Stillbirth
Early or Late
- Hepatomegaly
- Meningitis
- Rash
- CBC changes
- Bone changes
- Blindness
- Deafness
- CNS damage
Most important thing to prevent congenital syphilis
Screen ALL pregnant women
What is Vaginitis?
- Vaginal discharge/discomfort
- Not necessarily an “-itis” (inflammation)
Common causes of Vaginitis
- Bacterial vaginosis
- Candida
- Trichomonas
- Many other infectious and non-infectious causes
Normal vaginal flora
Lactobacillus and other good bacteria
Epidemiology of HPV and genital worts
Prevalent (mostly asymptomatic)
Signs & symptoms of HPV and genital worts
- Mostly asymptomatic
- Some strains more likely to cause warts (6, 11)
- Some strains more likely to cause dysplasia (16 & 18 > 31, 33, 35, 52, 58)
- Infection and warts may spontaneously resolve
- Worse in immunocompromised

HPV strains more likely to cause warts
6 & 11
HPV strains more likely to cause dysplasia
16 & 18 > 45, 31, 33, 35, 52, and 58
HPV tropism
Only infects squamous epithelial cells
Pathology of HPV
Viral E6 and E7 proteins immortalize squamous cells -> cervical, anal, head/neck squamous cancer
Treatment of HPV
- No antiviral medication
- Vaccine greatly reduces warts and dysplasia
- The vaccine effective against multiple strains
Prevalence of cervical dysplasia

Principles of STI management
- Evaluate patient for other STIs, including HIV
- Evaluate and treat all recent partners
- Educate patient: treatment failure, reinfection, prevention
- Condoms reduce risk
- Notify public health department (reportable diseases)
- Follow CDC treatment guidelines