STI's Flashcards
Gonorrhoea - What is it caused by?
Neisseria gonorrhoeae, inncubation period - 5/6 days.
Gonorrhoea - sy/sx men
10% have no sy, sx - thick profuse yellow discharge, dysuria. Rectal and pharyngeal infeciton is often asymptomatic
Gonorrhoea - sy/sx women
vaginal discharge, dysuria or intermenstrual/post-coital bleeding
Gonorrhoea - dx/ix
Nucleic Acid Amplification Test (NAAT) on urine or swab from an exposed site – vagina, rectum, throat. Could be self-obtained or clinician-obtained.
Gram stained smear from urethra/cervix/rectum in symptomatic people.
Culture of swab-obtained specimen from an exposed site using highly selective lysed blood agar in a 5% CO2 environment. Should be done for all confirmed cases to assess antibiotic sensitivity.
Gonorrhoea - tx
Ceftriaxone. Followup if tx is working after 2 weeks.
Gonorrhoea - complications
Male: Epididymitis, Female: Pelvic inflammatory disease. Bartholin’s abscess. [Gonococcal ophthalmia neonatorum.] Both: Acute monoarthritis usually elbow or shoulder.
Chlamydia - what is it caused by?
Chlamydia trachomatis, people under 25, sexually active teenage women
Chlamydia - sy/sx men
> 70% asymptomatic, sx- Slight watery discharge, dysuria,
Chlamydia - sy/sx women
> 80% asymptomatic, vaginal discharge, dysuria, intermenstrual/post-coital bleeding. Both men and women may get Conjunctivitis
Chlamydia - dx/ix
First void urine in men. Self-taken or clinician-taken swab from cervix, urethra, rectum as appropriate.
All specimens tested using a NAAT
Chlamydia - Tx
Doxycycline 100mg for 1 week (if pregnant give Azithromycin once), then followup at 3-12 months
Chlamydia - complications
Men Epididymitis. Women: PID and hence ectopic pregnancy, pelvic pain and infertility. Probably only ~1% of women who get chlamydia will develop a problem with their fertility Both: Reactive arthritis/ Reiter’s syndrome – urethritis/cervicitis + conjunctivitis + arthritis
Herpes - what is it caused by?
HSV1 and 2 (inncubation period of 5 days to months, some may nnever get symptoms), very common, HSV2 is an important cofactor for HIV transmission
Herpes - sy/sx
80% have no symptoms. The rest have recurring symptoms – monthly, annually. Burning/itching then blistering then tender ulceration. Tender inguinal lymphadenopathy. Flu-like symptoms. Dysuria, Neuralgic pain in back, pelvis and legs,
Herpes - dx/ix
clinical, swab from lesionn then PCR
Herpes - tx
Primary outbreak: Aciclovir: various regimens – eg 400mg tds for 5 days, Lidocaine ointment.
Infrequent recurrences: Lidocaine ointment. Aciclovir 1.2g once daily until symptoms gone (1-3 days)
Frequent recurrences: Aciclovir 400bd long-term as suppression.
Herpes - complications
Autonomic neuropathy, (urinary retention), neonatal infection, secondary infection.
Syphilis - what is it caused by?
Treponema pallidum subspecies pallidum, >90% MSM
Syphilis- sy/sx
Primary Local ulcer (CHANCRE), Secondary Rash, mucosal ulceration, neuro symptoms, patchy alopecia, other symptoms.
Early latent no symptoms but <2years since caught. Late latent no symptoms but >2 years since caught. Tertiary Neurological, cardiovascular or gummatous – skin lesions, (all v rare).
Syphilis - dx/ix
Clinical signs, urethral swab then TPPA - Serology for TP IgGEIA, and RPR, PCR on sample from an ulcer
Syphilis - tx
Early (<2 yrs and no neurological involvement): Benzathine penicillin 2.4 MU im once Or Doxycycline 100mg bd po 2 weeks
Late (>2 years) and no neurological involvement: Benzathine penicillin 2.4MU im weekly for 3 doses, Doxycycline 100mg bd po 28 days
Syphilis - complications
neurosyphilis – cranial nerve palsies are commonest, cardiac or aortal involvement.
infectious diseases wihich may be accquired from abroad on a buisniess trip…
HIV, HCV, chlamydia, genital or oral HSV, HBV, anal genital warts.
Trichomoniasis - What is it caused by?
Trichomonas vaginalis, more common in middle aged women
Trichomoniasis - sy/sx
Men: usually asymptomatic, Women: 10-30% asymptomatic, Profuse thin vaginal discharge - greenish, frothy and foul smelling. Vulvitis.
Trichomoniasis - dx/ix
PCR on a vaginal swab. NB not validated on urine yet so no test for men.
Point of Care - Microscopy of wet preparation of vaginal discharge.
Trichomoniasis - tx
Metronidazole 400mg po bd for 5 days or 2g single dose.
Trichomoniasis - complications
miscarriage, preterm labour
Anogenital warts - what is it caused by?
Human Papilloma Virus types 6 and 11 (and occasionally type 1)
Anogenital warts - sy/sx
Lumps with a surface texture of a small cauliflower. Occasionally itching or bleeding especially if perianal or intraurethral.
Anogenital warts - dx/ix
Appearance. Biopsy if unusual – to exclude intraepithelial neoplasia, but this is rarely needed.
Anogenital warts - tx
Podophyllotoxin (brands warticon and condyline), imiquimod (brand Aldara). Both home treatments, Others – cryotherapy, Bulky warts – diathermy, scissor removal.
Give examples of sexually transmitted bacteria, viruses and parasites
Bacteria - Chlamydia trachomatis, Klebsiella granulomatis, Mycoplasma genitalium
Viruses - HSV, HIV, HPV, Molluscum contagiosum virus
Parasites - Pthirus pubis, Sarcoptes scabei, Trichomonas vaginalis
what are important features of STI’s
They’re transmissible, partner notification important, Asymptomatic most of the time, symptoms and screening, All manageable but not always curable, treatment/prevention of complications, Avoidable, primary prevention = education
sy in general from sti’s
Morbidity, psychological distress and unpleasant symptoms: Ulceration, Lumps, Urethritis, Discharge, Rashes
Systemic symptoms: Fever, Rash, Lymphadenopathy, Malaise, Infertility
