5/26- Sexually Transmitted Diseases Flashcards
Minimum evaluation requirements for someone with even 1 STD
- Syphilis- RPR
- Chlamydia (urethral/cervical swab)
- Gonococci
- HIV antibody
- Hep B antibody
Why is compliance with therapy for STDs notoriously poor?
- Much denial around diseases (contributing to behavior)
- Most persons who acquire are likely not in full control of their own health issues (excluding innocent bystanders)
What is the best documented means of STD control?
Condoms (not abstinence)
What are some non-typical STD infections?
Enteric diseases in MSM:
- Shigella (flexneri)
- Cryptosporidia
Causes of venereal chancres?
- Syphilitic chancre;treponema pallidum
- Chancroid; haemophilus ducreyi
- Herpes
Causes of nonvenereal chancres?
- Fixed drug eruption
- Trauma (clean or purulent/2ndary infxn)
- Unknown (Behcet’s dz)
Causes of warts/bumps?
- Human papillomavirus (venereal)
- Molluscum contagiosum
Causes of condyloma lata?
- Extension of syphilitic infxn if 1’ untreated
Characteristics of syphilitic chancre?
- Clearly demarcated with raised margin and clean base
- Single or multiple
- Genital lesions are painless
- Most are genital (shaft of penis, labia, cervix), but possible in mouth, anus or rectum
- Enlarged regional lymph nodes
Early diagnosis of syphilis?
- Scraping of chancre (for 1’ infxn) and Darkfield exam
- Early on, RPR may still be negative
When are women typically diagnosed with syphilis?
When it’s a 2’ infxn (not 1’), since the chancre is painless
Characteristics of chancroid lesion of Haemophilus ducreyi?
- Jagged margin and purulent base
- Painful
- Single or multiple
- Genital only
- Greatly enlarged regional lymph nodes; painful (typically diagnosed syndromically)
Characteristics of herpes lesions?
- Multiple vesicles that ulcerate because of friction from underwear
- Painful
- 1st episode has systemic Sx plus enlarged regional lymph nodes (less in subsequent bouts)
- Highly associated with relapse; recurring disease (less severe). Possibly have lifelong shedding of virus even if no lesions
What is the most common cause of herpes? Percent?
- Herpes simplex type 2
- Causes > 80%
Characteristics of fixed drug eruption?
(Nonvenereal chancres)
- Single
- Round, clearly demarcated, clean base
- May be pruritic
- Allergy to sulfas, tetracycline, or macrolides (while taking, 3-4th day); unknown reason
What is the most common cause of HPV warts?
Associated with CA?
Vaccine coverage?
Epidemiology?
- Usually types 6 and 11
- (recall 16 and 18 are associated w/ CA of cervix or anus)
- All 4 are covered by vaccine
- Common infection among sexually active young adults (65% of inner city adolescent women in 1 study)
Treatment for HPV warts?
Topical; stimulate inflammatory response
- Podphyllin
- Imiquimod
Cause of Molluscum contagiosum?
Pox virus
Treatment for Molluscum contagiosum?
- Self-limited
- Liquid nitrogen
Characteristics of condyloma lata?
- Plaque-like eruptions
- Vulva, perineam, or anus
- Occurs especially in MSM
- Highly contagious
- May be seen in moist areas as part of 2’ syphilis (but rare recently)
Using RPR to diagnose syphilis:
- % positive in diff stages?
- Titer level indicates __?
- 75-80% + with 1’
100% + with 2’
- Height corresponds to activity; rises steadily, peaking in 2’ and somewhat subsides when latent; recurs in 3’ (but highest in 2’)
1’: (-) or (+) up to 1:32
2’: 1:64 - 1:256
latent: 1:2 - 1:8
3’: 1:4 - 1:32
treated: (-) following quick treatment (1’ or 2’ infxn)
serofast: <1:4
What is serofast?
- When RPR remains + at very low titer (<1:4)
What is a biological false positive in regards to RPR?
- Bad terminology
- RPR may be positive at low titer in aging or under certain immunologic/infectious diseases
Using MHA-TP to diagnose syphilis:
- What does it stand for?
- % positive in diff stages?
- Titer level indicates __?
- Micro Hemagglutinating Ab to T. pallidum
- 90% + with 1’
100% with 2’
- Current or prior infxn (once positive, it remains so for life); can be used to EXCLUDE but not DIAGNOSE syphilis
- Highly sensitive and highly specific
2’ syphilis can cause what non-venereal presentation (1)?
- Characteristics?
- Diagnosed in this stage for which patients?
Generalized rash
- Widespread maculopapular rash
- Unusual b/c it involves palms and soles!
- Many forms, but only rarely vesicular except on palms and soles (may be vesicular or pustular)
- Diagnosed in this stage in women and MSM men in whome painless, hidden primary lesion goes unrecognized
Other presentations of 2’ syphilis (many)?
- Generalized Sx (uncommon unless AIDS)
- Lymphadenopathy (regional is common but generalized is not)
- Hepatitis (subclinical; lab abnl; common)
- Arthritis (rare)
- Osteitis (modern era; only seen on bone scan)
- CNS invasion (regularly occurs by asymptomatic; sets stage for neurosyphilis)
- Uveitis
- Nephrotic syndrome (deposition of circulating immune complexes)
- Mucous patches
- Eyebrow loss; patchy alopecia
Nuances of syphilis in HIV pts?
- Surprisingly little difference early on (1’, 2’, 1st yr of latency)
- Much slower response to drugs
- Many more remain serofast after treatment
- Early neurosyphilis (meningeal or meningovascular)
- Syphilitic lesions increase likelihood of spread of HIV
Fate of pts with 2’ syphilis?
Everyone eventually has spontaneous remission (4-8 wks) into latency (absence of any clinical manifestations
Fate of pts with untreated latent syphilis?
- Recurrence of 2’ lesions in 25% within 1-2 yrs (early latency time frame)
- Does not recur in late latency (>2 years)
Time frame of neurosyphilis in those with HIV?
- May precede AIDS
- Many with reactive RPR (>1:32) and no Sx have CNS involvement as proven by +VRDL and cells in CSF
Pathology of neurosyphilis in those with HIV?
- Cranial nerve abnormalities: II (retinitis), VII, VIII, others
- Meningitis: subclinical, mild or frank +/- CN abnormalities
What does RPR test?
Antibody to cardiolipin
Fate of those with untreated syphilis?
“Rule of thirds”
- 1/3 return to (-) serologic tests and never have evidence of dz
- 1/3 maintain active serologic tests but never develop evidence of dz (late latent)
- 1/3 develop 3’ syphilis
[40% neurosyphilis, 40% gummas of soft tissues/organs, 20% CVD (aortitis), perforated palate)
What does MHA-TP test?
Antibody to outer membrane proteins of T. pallidum
Using ELISA to diagnose syphilis?
- Good for screening but not diagnosing
- Gives many false positives
- Proposed 2-step screening: ELISA first, then RPR
How to diagnose venereal ulcers due to Haemophilus ducryei?
- Culture
- PCR
- Syndromic, especially in developing countries
How to diagnose venereal ulcers due to Herpes?
- Rapid nucleic acid identification
- Culture (distinguishes HSV1 and 2; prognostic value)
Therapy for genital chancre (overview)
- Immediate Darkfield
- RPR (some delay okay)
Treatment if Darkfield + for T. pallidum?
Benzathine penicillin G (prolonged to treat slow replication of organism)
Treatment if Darkfield - but unknown RPR?
Treat for chancroid pending RPR with:
- Azithromycin (1 oral dose) or
- Ceftriaxone (1 IM dose) or
- Ciprofloxacin (3 days) or
- Erythromycin (4x per 7 days)
(these have a low threshold for treating syphilis anyway pending RPR that may be -)
Treatment for initial bout of genital herpes?
- Acyclovir
- Famciclovir
- Valacyclovir (7-10 days)
Treatment for recurrent bout of genital herpes?
Lower dose and 5 day treatment only
Usual understanding of neurosyphilis (non-HIV): - Time frame? - Affects what tissue? - Manifestations?
- Appears 4-40 yrs after onset of latency, so older subjects (common pre-penicillin and still today)
- Affects ectodermal structures like neuronal tissue
- Broad range manifestations: tabes dorsalis, paresis, dementia, grand dementia of insane, CVA, death
Causes of urethritis or cervicitis?
- Gonorrhea (Neisseria gonorrhoeae)
- Chlamydia trachomatis
- Mycoplasma genitalium
- Trichomonas vaginalis??
Gonococcal and non-gonococcal tend to coexist! (esp chlamydia and gonorrhoea)
Characteristics of Gonorrhea?
- Exuberant purulent discharge with pain (although may be minimal and non-symptomatic infxn occurs)
- Gonococcus may cause proctitis or pharyngitis (pharynx is colonized by gonococci in 5% of MSM)
Characteristics of non-gonococcal urethritis?
- Pain less severe
- Exudate scanty, not purulent
- MCC of urethritis in certain populations
Special agar for Neisseria (gonorrhoeae)?
Thayer Martin agar:
- Chocolate agar
- Vancomycin (vs. Gm +)
- Nystatin (vs. candida)
- Gentamycin (vs. Gm- rods)
Gonococcal vs. Nongonococcal urethritis?
Gonococcal: inner city, painful, copious/purulent discharge, many WBC and organisms, responds to cell wall ABx and maybe non cell wall
Non-Gonococcal: universities, irritating, scanty discharge, few WBC/organisms, no response to cell wall Abx but responds to non cell wall
Complications of gonococcal urethritis in men? women?
Men:
- Local: epididymitis
- Disseminated: arthritis, skin lesions
Women:
- Local: PID, infertility
- Disseminated: arthritis, skin lesions
Complications of NON-gonococcal urethritis in men? women?
Men:
- Epididymitis only and rare
Women:
- PID (other bacteria may contribute)
- Infertility (major worry)
Chlamydia stats for adult population?
3-5% in 15-19 yo
Bacterial resistance of M. genitalium?
> 40% resistant to azithromycin
Diagnosis of urethritis and cervicitis (4)?
Gm stain of pus
- >95% true + for men
- Other bact in women may confuse
- Gm stain of pharynx/rectum uninterpretable
Culture
- Chocolate agar using Abx to supress bacteria /fung (Thayer-Martin) + CO2 supplement
- Could just use chocoloate if TM not available
Nuclei acid amplification (PCR) or rapid immunoassays for:
- N. gonorrhoeae
- Mycoplasma
- Chlamydia
Urine specimen:
- Good in men but cervical swab unreliable to diagnose gonorrhoea
Treatment for gonorrhea?
High level, short duration (1 dose) of 3rd gen cephalosporins
- Cefixime (oral)- now resistance
- Ceftriaxone (IM)
NO quinolones (resistance)
Treatment for non-gonococcal urethritis?
Azithromycin
Try to treat in clinic since at risk population not likely to return
- Used (but no approved) for gonorrhea, esp if cephalosporin allergy; test cure 1 wk later; some resistance
- Higher cure rate than doxycycline for Mycoplasma genitalium
Causes of pelvic inflammatory disease?
Vary with age and SES (just like gono/non-gono urethritis):
- Gonococci (inner cities)
- Chlamydiae (universities)
- Mixed infxns with Gm - or anaerobic flora +/- chlamydia or mycoplasma
Pelvic Inflammatory Disease involves what process?
Spread of infxn from vagina and cervix to uterus fallopian tubes, and/or peritoneum
Symptoms of PID?
- Lower abdominal pain (unrelated to meals/bowel mvts)
- Dyspareunia (pain on intercourse)
- +/- vaginal discharge
On exam: Minimal CDC criteria:
- Lower abdominal tenderness
- Tenderness w/ cervical mvt
- Adnexal tenderness
Additional criteria:
- Fever
- Cervical exudate
Lab results with PID?
- Elevated WBC count
- Pus at cervix (or culdoscopy)
- Microbiologic confirmation of N. gonorrhoeae or Chlamydia
Treatment for PID?
- Hospitalize?
- Inpatient?
- Outpatient?
Must decide whether to hospitalize (often done to initiate therapy):
- Seriously ill
- Unable to take oral meds
- Uncertain diagnosis
- Abscess present
- Pregnancy
- Unreliable pt
Inpatient:
- Cefoxitin or Cefotetan AND
- Doxycycline
OR
- Clindamycin AND
- Gentamicin AND
- Dyoxycycline
Outpatient (14 d):
- Ceftriaxone or Cefoxitin AND
- Doxycycline
All of these +/- metronidazole for 14 days
Complications of PID?
- Infertility (chlamydia infxn may be asymptomatic!)
- Ectopic pregnancy
What causes buboes?
- Syphilis
- Chancroid
- Lymphogranuloma venereum (LGV) from C. trachomatis
- Cat scratch fever if lymphadenopathy without genital lesion
Characteristic of enlarged inguinal LNs in syphilis?
- Modest size
- Minimally tender
Characteristic of enlarged inguinal LNs in chancroid?
- Huge
- Exquisitely tender
- Overlying skin is very thin; LN may rupture through skin
Characteristic of enlarged inguinal LNs in LGV?
- Very large
- Not so tender
- Chronic
- LNs become “matted” and involved overlying skin, causing thickening
- Caused by L. serovars of Chlamydia trachomatis (diff from those causing urethritis)
What else will be seen if suspect that syphilis or chancroid are causing inguinal LN enlargement?
Penile or scrotal lesion (always!)
