STIs Flashcards
Impact of STIs?
- sterility, cancer, and death
RFs for STIs
- unmarried
- residence in urban area
- new sex partners
- multiple sex partners (concurrent)
- history of a prior STI
- illicit drug use
- contact with sex workers
- young age (15-24)
- African-American race
- admission to correctional facility or juvenile detention center
- meeting partners on the internet
Causes of genital ulcers (STI and noninfectious etiology)
STI:
- HSV
- Treponema pallidum (syphilis)
- Haemophilus ducreyi (chancroid)
- chlamydia trachomatis (lymphogranuloma venereum; LGV)
noninfectious etiology:
Behcet’s disease
fixed drug reactions and trauma
HSV infection -> causative agents
- causative agents: HSV- 1 and HSV-2
- no longer separated into genital and oral
- both serotypes can cause either type of infection
Very common: 50 mill people in US - frequently under-recognized b/c infection is often subclinical
Types of HSV infection
Primary: infection in a pt w/o abs to HSV-1 or HSV-2
nonprimary: 1st episode infection due to acquiring HSV-1 w/ preexisting abs to HSV-2 or vice versa
Recurrent: reactivation of genital herpes in which the HSV type recovered in the lesion is the same type as the abs recovered in the serum
Symptoms of HSV infection
- Primary: highly variable from very symptomatic to asymptomatic
- sxs tend to be more severe in women than in men
- systemic sxs, local pain/itching, dysuria, lymphadenopathy
- Dysuria can be due to acute urinary retention or more rarely to lumbosacral radiculomyelitis
nonprimary: less symptomatic than first episode
recurrent: less severe, shorter duration
- asymptomatic shedding
- if women get in cervix or vagina it could go unnoticed, shedding virus without lesions
Transmission of HSV
- highly transmittable
- can be transmitted by oral-genital contact
- greater risk of acquiring HSV w/ male source
- 70% of transmission occurred during periods of asymptomatic shedding
- condom use 50% decline in transmission
- HSV -2 genital ulcer disease has been linked to an increased risk for acquiring HIV-1 infection (any break in the skin increases risk of HIV)
Dx HSV
- viral culture: if active lesions present
- PCR: more sensitive
- Direct fluorescent ab
serology:
- type-specific ab testing of serum
- helps to determine if the pt is at risk of acquisition
- determines if pt has hard evidence of prior infection
- can do screening for HSV
Tx of HSV
drugs:
acyclovir
Famcilovir -> more bioavailable
Valacyclovir -> more bioavailable/BID
primary genital HSV: should be treated (w/in 72 hours) - decreases duration of symptoms - increases healing of lesions - decreases viral shedding - analgesics may be required/ sitz baths helpful
Recurrent disease: chronic suppressive therapy: expensive and may not be covered by all insurance carriers
- episodic therapy: start at 1st sign of prodromal symptoms usually take for 3 days
- no intervention
HSV in pregnancy
- most common mode of transmission is from direct contact of fetus w/ infected vaginal secretions during delivery
- Maternal immunity is impt: if mother contracted HSV before pregnancy -> have abs that will transfer to baby
- biggest risk: if mother contracted HSV while pregnant
- Acyclovir can be used to tx a primary infection
prophylactic C-section: do if active lesions at birth canal, not recommended if mother has no active lesions or if lesions have crusted at time of delivery (or have feeling of prodromal sxs), not recommended if have active nongenital HSV lesions
Prevention of HSV
- counseling!!!
- pts need to be educated that they may not have acquired the infection recenetly and that there has not necessarily been infidelity in a monogamous partner
- education on recurrences
- monogamous partner testing
- telling future sexual partners
Syphilis causative agent and tests available?
- Treponema palidum
can’t be cultured, can be seen with dark field microscopy - serologic tests available: nontreponemal: VDRL, RPR, TRUST/ reported as titers
treponemal: reported as reactive or nonreactive: - fluorescent treponemal ab absorption
- microhemagglutination test for abs to T. palidum
- Treponema palidum particle agglutination assay
- Treponema pallidum enzyme immunoassay
Who should be screened for Syphilis?
- pt with suspected disease
- screening high risk populations (pts with other STIs, persons with multiple sex partners)
- routine screening of pregnant women
- commercial sex workers
- all sexually active HIV infected pts at least annually, more frequent screening for those w/ multiple sex partners and unprotected intercourse
What is syphilis associated with?
- reportable infection in the U.S.
- number of cases increasing since 2001: primarily in MSM (HIV pop not using protection, syphilis started to spread then branched out into other populations
- also in heterosexual pop.
- *It is associated with an increased risk for acquisition and transmission of HIV
- all pts who are dx with syphilis should be offered HIV testing and counseling
Transmission of Syphilis?
- Primary and secondary syphilis produce chancres, mucous patches and condyloma lata
- estimated transmission occurs in 30% exposed to someone who is infected
- syphilis can be spread by kissing or touching a person who has active lesions on the lips, oral cavities, breasts or genitals
- it can be acquired through passage through the placenta
Primary syphilis characteristics
- incubation period of 2-3 weeks from inoculation - a papule forms and soon ulcerates to the chancre
- chancre is usually painless
- usually there is bilateral lymphadenopathy
- chancres heal spontaneously within 3-6 weeks even without tx
- widespread dissemination of the organism occurs at the same time
Secondary syphilis characteristics
- weeks to a few months later 25% of people with untreated infections will develop systemic illness:
- rash: any form BUT vesicular, includes palms and soles.
- Gray/white lesions warm moist areas -> condyloma lata
- systemic sxs
- lymphadenopathy
- alopecia (patchy)
- hepatitis
- GI abnormalities ( can be misdx as lymphoma)
- musculoskeletal and renal abnormalities
- ocular disease
Tertiary syphilis characteristics
- 1-25 years after secondary syphilis: early tertiary syphilis presents = year
- late tertiary syphilis presents > 1 year from initial infection
systems involved:
-subcutaneous tissue (gumma) - granulomas
-CV: ascending thoracic aorta becomes dilated aortic valve regurgitation occurs.
CNS (most common):
early: meningitis, meningiovascular disease
late: general paresis, tabes dorsalis, ocular, otosyphilis
Characteristics of neurosyphilis
- when suspected need to do a lumbar puncture
CSF findings: lymphocytic pleocytosis, elevated protein, + CSF-VDRL and or FTA-ABS
Need to follow CSF during tx to make sure there is a response (lumbar punctures)
Tx of early syphilis
For primary, secondary syphilis and early latent:
- 2.4 mill units of benzathine PCN G IM
- for PCN allergies DOC: doxy 100 mg BID for 14 days
- tetracycline, azithro, and ceftriaxone are other alternatives although not well documented.
