Sexually Transmitted Diseases Flashcards
Definition
Infections that primarily transmit via sexual or related close bodily contact
Treponema Pallidum recap: disease, clinical course, outcomes, treatment
Disease: Syphilis
- spirochetes
- non-cultivable in laboratory
Recap clinical course:
- 10-90 days: primary syphilis - painless genital ulcer (chancre)
- secondary syphilis - constitutional symptoms, rash, hepatitis, nephritis, uveitis etc. (widespread dissemination)
- latent syphilis (early = 1yr from contact; late = >1yr)
Outcome:
- remission (2/3)
- tertiary syphilis - CVS (aortitis>aortic aneurysm) and CNS morbidities (1/3)
Treatment:
- benzathine penicillin IM (1 dose if early latency, weekly x3 if late)
- doxycycline/erythromycin if allergy
Treponema Pallidum Diagnosis
- dark ground microscopy - observe for motile spirochetes (false negatives as organism can’t survive long outside host; not routinely used as need dark field microscope)
Serous fluid from chancre:
Non-treponemal test (VDRL; venereal disease research laboratory): measure total IgM and IgG in titre
- SCREENING (non-specific)
- MONITORING treatment (quantitative)
- limitations: false +ve in pregnancy, rheumatoid factors, previous syphilis (need to rule out in Hx)
Treponemal test (TPPA or FTA-ABS)
- T. pallidum particle agglutination assay - qualitative test
- CONFIRMATORY (higher specificity) – rule out syphilis if -ve
- turns -ve after treatment (but not used as monitoring)
- limitation: cost
(CSF for neurosyphilis)
Neisseria gonorrhoeae: gram’s stain, growth requirements, symptoms, diagnosis, treatment
Gram -ve diplococci
- attachment facilitated by pili to columnar epithelial cells
Delicate! - bedside inoculation onto chocolate agar, special transport medium and culture medium; extra CO2 requirement
Symptoms:
- Male: urethral discharge and dysuria
- Female: asymptomatic (endocervicitis)
Diagnosis:
- URETHRAL DISCHARGE for Gram’s STAIN AND CULTURE
- ENDOCERVICAL SWAB (columnar cells) for nucleic acid testing (not vaginal swab!)
Treatment:
- IM ceftriaxone
(add azithromycin if community-based)
Chancroid: organism, gram’s stain, growth requirements, symptoms, diagnosis
Haemophilus ducreyi
- small gram negative bacilli
- requires special enriched medium and fresh preparation – difficult to culture
- found in Africa, SE Asia, developing countries
Symptoms:
- PAINFUL ulcer of genitalia (chancre)
- enlargement and suppuration of inguinal nodes
Enhances HIV transmission
Diagnosis:
- clinical
Chlamydia trachomatis: serovars, symptoms, diagnosis, treatment
Obligate intracellular bacteria
- recall serovars A-C = trachoma
- D-K = mucosal diseases
Symptoms:
- male: NON-GONOCOCCAL URETHRITIS (urethral discharge)
- female: cervicitis, PID, peri-hepatitis
- newborn: inclusion conjunctivitis, pneumonia of newborns
Diagnosis;
- IMMUNOFLUORESCENCE staining of URETHRAL DISCHARGE
- Nucleic acid testing
Treatment:
- Azithromycin
- Doxycycline
Newborn baby with sticky eyes DDx
Vaginal delivery acquired infection (mother usually asymptomatic)
GONOCOCCAL ophthalmia neonatorum
Neonatal CHLAMYDIA conjuncitivitis
Lymphogranuloma venereum: cause, symptoms, diagnosis
Chlamydia trachomatis serovars L1-L3
- lymphoproliferative reaction and lymphangitis
- tropical and subtropical areas
Symptoms:
- painless, small ulcer
- inguinal nodes enlarged, painful and may rupture (bubo)
Diagnosis:
- usually clinical
- molecular testing available in reference lab only
HSV genital infections: symptoms/ extra genital lesions, complications in pregnancy, diagnosis, treatment
HSV-2 mainly
Symptoms:
- genital lesions: cluster of painful ulcers and vesicular lesions on mucosa
- RECURRENCE is common (reactivation at localised site)
- neonatal disseminated herpes (primary herpetic encephalitis with high mortality)
- fluid from vesicles is infectious (autoinoculation e.g. herpes keratitis; extra genital lesions e.g. herpetic whitlow)
- facilitates HIV transmission
Diagnosis:
- VESICULAR FLUID for viral CULTURE/ PCR
- Ag detection (IF from skin scrapings)
Treatment:
- ORAL Acyclovir
- Suppressive therapy for recurrent infections
Molluscum contagiosum: virus, transmission, spot diagnosis, outcome
Pox virus
- benign viral infections of the skin
- transmit by direct contact, fomites or sexual contact
Shining pearly white hemispherical umbilicated papule, enlarging slowly
- facial lesions seen in AIDS
Outcome:
- most cases self limiting in 6-9 months
Diagnosis:
- clinical (spot diagnosis)
Human Papilloma Virus: transmission, symptoms, diagnosis, treatment
> 200 types transmitted through abrasion in skin, sexual contact
Tropism:
- cutaneous/ non-genital warts (plantar warts)
- anogenital warts (genital warts, cervical cancer) - HPV6/11
Diagnosis:
- clinical
Treatment:
- topical cream (imiquimod cream)
- ablation
Vaginitis DDx
Candida albicans
Trichomonas vaginalis
Bacterial vaginosis
Candida Vaginitis: transmission, at risk groups, symptoms, diagnosis, treatment
Candida albicans
NOT always sexually transmitted (most cases non-STI)
- pregnancy, antibiotics, immunosuppression, DM
Symptoms:
- PRURITUS vulvae, vaginal discharge
(vulvovaginitis, balanoposthitis in man)
Diagnosis:
- marked discharge “curd cheese” on bedside speculum exam
- vaginal swab for fungal culture if in doubt
Treatment:
- imidazoles pessary/ cream PV
Trichomoniasis: organism, symptoms, diagnosis, treatment
Trichonomona vaginalis (flagellate protozoan) - sexual transmission
Symptoms:
- male: mostly asymptomatic
- female: MALODOROUS vaginal discharge
Diagnosis:
- VAGINAL SWAB for CULTURE
Treatment:
- metronidazole (note DDI with COC)
- tinidazole
Bacterial Vaginosis: organism, symptoms, diagnosis, treatment
POLYMICROBIAL
- imbalance and overgrowth of anaerobes e.g. peptostreptococcus; Gardnerella vaginalis (MC)
Symptoms:
- vaginal discharge
- “FISHY SMELL”
Diagnosis:
- VAGINAL SWAB for gram’s STAIN –> “CLUE CELL” (squamous epithelial cell packed with dense coccobacilli blurring edge of cell)
Treatment:
- metronidazole
