STIs Flashcards
What factors affect the transmission of genital infections?
Age Ethnicity Socio-economic status Age at first sexual intercourse Number of partners Sexual orientation Condom use Menstrual cycle
Describe the epidemiology of sexually transmitted infections (STIs)
Chlamydia is the most common STI
Highest rates amount 20-24 year olds
Black men most likely to have chlamydia
Outline testing for STIs in men
Urine analysis = gonorrhoea/chlamydia, midstream urine for C+S
Urethral sampling = gonorrhoea cultures, gram stain
Rectal and pharyngeal samples = gonorrhoea and chlamydia
Swab of ulcer base = herpes, PCR for syphilis
Bloods = syphilis, blood borne
Outline testing for STIs in women
Vulvovaginal swabs = gonorrhoea and chlamydia
High vaginal swabs = trichomonas, candida
Endocervical swabs = gonorrhoea
Urine = SU for C+S
Rectal and pharyngeal samples = gonorrhoea NAAT
Swab ulcer base = herpes, PCR for syphilis
Bloods = syphilis, blood borne
Vaginal pH
Outline general management of STIs
Treatment = Abx
Screen for other STIs
Contact tracing
STI prevention
List the most common sexually transmitted infections, identifying the infecting organism in each case
Chlamydia = Chlamydia trachomatis
Gonorrhoea = neisseria gonorrhoea
Herpes = herpes complex ½
HIV = human immunodef virus
Syphilis = treponema pallidum
Genital warts = human papillomaviruses (HPV)
Describe the clinical presentation, diagnosis and management of chlamydial infections
Chlamydia trachomatis
M = urethritis, dysuria, epididymitis, proctitis, prostatitis
F = mostly asymptomatic, increased discharge, bleeds
Diag = swabs (urethral, vulvovaginal, rectal, pharyngeal), NAAT, NOT VISIBLE on microscopy
Treat = azithromycin 1g PO
Describe the clinical presentation, diagnosis and management of gonorrhoea
Neisseria gonorrhea
M = urethral discharge, dysuria, anal discharge
F = asymptomatic, altered discharge, lower abdo pain
Diag = gram stain, NAAT, cultures
Treat = IM ceftriaxone 500mg + 1g azithromycin PO
Describe the clinical presentation, diagnosis and management of genital herpes
incubation 3-14d
Asymptomatic, painful ulceration, dysuria, vaginal discharge
Diag = viral detection at ulcer base, serology, syphilis serology, PCR
Mx = sick note, rest, analgesia, saline washing, systemic acyclovir, lidocaine ointment, avoid sexual contact
Comp = urinary retention, adhesions, meningism, emotional distress, recurrences
No cure - sitting dormant in dorsal root ganglion
Preg: primary infection in 1st trimester - CS
Explain the 3 reasons azithromycin is used on top of ceftriaxone
Azithromycin boosts activity of ceftriaxone
Lowers levels of resistance
35% of gonorrhoea cases also have chlamydia – treatment therefore for both
Describe the clinical presentation, diagnosis and management of genital warts
Human papillomaviruses 6/11
- High-risk = HPV 16 and 18
Benign painless ep or mucosal outgrowths on penis, vulva, vagina, urethra, cervix, perianal skin - itching, soreness, urethral/PR bleed, distortion of urine flow
Diag = biopsy
Treat =
- Podophyllotoxin (Warticon) antimitotic - good for mucous membrane warts
- Imiquimod (Aldara) stim NK activity + macrophage nitric oxide secretion - good for thick keratinised warts
- Cyrotherapy - complex warts, preg
- Cervical warts - refer to gynae fo colposcopy
HPV vaccination
What is syphilis?
Treponema pallidum
S+S = chancre (firm, painless, non-itching skin ulceration), inguinal lymphadenopathy
Ix = swab, microscopy, PCR, Treponemal enzyme immunoassay (EIA), Treponema pallidum particle agglutination assay (TPPA), rapid plasma reagin test (RPR), full STI screen
Complications = CV syphilis, neurosyphilis, gumma
(BTS)
Diffuse maculo-papular rash on hands and feet - think syphilis
Mx = benzathine penicillin injection, partner notification
What is trichomonas vaginalis?
Flagellated protozoa
M = infect urethra, urethral discharge, dysuria
F = vaginal discharge (yellow, frothy)
Diag = cultures, NAAT
Treat = metronidazole 400mg PO BD 5d
