STIs Flashcards
Examples of infections which can be transmitted sexually but aren’t STIs
- Hep A
- Hep C
- Zika
- Giardiasis
Difference between STI and STD
- STI - infection which is predominantly sexually transmitted
- Chlamydia trachomatis
- HIV
- STD - disease caused by infection
- HPV is STI and warts is the STD
General principles of STI
- If have one, risk of having others
- Most symptomatic - detection difficult
- Delay in diagnosis can lead to increased transmission and complications
- Can be traumatising
- Partner contact essential
- MD approach
Cause of gonorrhoea
- Neisseria gonorrhoea
Male symptoms of gonorrhoea
- 10% no symptoms (might have clinical signs)
- Thick profuse yellow discharge
- Dysuria
- Rectal and pharyngeal infections often asymptomatic
Female symptoms of gonorrhoea
- >50% have no symptoms
- Vaginal discharge
- dysuria
- Intermenstural/post-coital bleeding
Male complications of gonorrhoea
- Epididymitis
female complications of gonorrhoea
- Pelvic inflammatory disease
- Bartholin’s abscess [Gonococcal ophthalmia neonatrium]
Both complications of gonorrhoea
- Rare
- Acute monoarthritis - usually elbow or shoulder
- Disseminated gonococcal infection - skin lesions (pustular with halo)
Incubation period of gonorrhoea
- Average 5-6 days
- Range from 2 days - 2 weeks
Epidemiology of gonorrhoea
- Approx. 150 cases/year in Grampian
- Much less common than chlamydia
- Most cases men, often MSM
Diagnosis of gonorrhoea
- Nucleic acid amplification test (NAAT) on urine or swab from site
- vagina, rectum, throat - clinician or self 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
Treatment of gonorrhoea
- Blind treatment with ceftriaxone 1g im
- Can also be treated according to sensitivities
Follow up of gonorrhoea
- Test of cure at 2 weeks
- Test of reinfection at 3 months
Cause of chlamydia
- Chlamydia trachomatis serovars D to K
- The rare Serovar L2b, which causes Lymphogranuloma venereum, usually gives symptoms of severe proctitis
Male symptoms of chlamydia
- >70% asymptomatic
- Slightly watery discharge
Female symptoms of chlamydia
- >80% asymptomatic
- Vaginal discharge
- Dysuria
- Intermenstrual/post-coital bleeding
Both symptoms of chlamydia
- conjuctivitis
Male complications of chlamydia
- Epididymitis
Female complications of chlamydia
- PID - hence ectopic pregnancy, pelvic pain and infertility
- Only 1% infertility problems
Both complications of chlamydia
- Reactive arthritis/Reiter’s syndrome
- Urethritis/cervicitis + conjuctivitis+ arthritis
Epidemiology of chlamydia
- Common - approx 2000 cases/year in Grampian
- Most cases people <25, especially sexually active teenage women
Diagnosis of chlamydia
- First void urine in men
- Self-taken or clinician-taken swab from cervix, urethra, rectum
- All specimens testing using NAAT
Treatment of chlamydia
- Doxycycline 100mg bd 1 week
- Azithromycin 1g po once if pregnant
Follow up of chlamydia
- test for reinfection at 3-12 months
- test of cure not needed unless symptoms persist
What causes herpes
- HSV 1 & 2
Symptoms of herpes
- 80% have no symptoms - the rest recurring
- Burning/itching then blistering then tender ulceration
- Tender inguinal lymphadenopathy, flu-like symptoms
- Dysuria, neuralgic pain in back, pelvis, legs
Complications of herpes
- Autonomic neuropathy (urinary retention)
- Neonatal infection
- Secondary infection
Incubation period of herpes
- About 5 days to months
- Some never report symptoms
Epidemiology of herpes
- Very common - 15-20%
- Both strains equally as common in genital infection
- Roughly equal between sexes
- HSV2 is important co-factor for HIV transmission
Diagnosis of herpes
- clinical impression Swab from lesion tested using PCR
Treatment of herpes
- Primary outbreak
- Aciclovir: various regimes e.g. 400mg tds for 5 days
- Lidocaine ointment
- Infrequent recurrence
- Lidocaine ointment
- Aciclovir 1.2g once daily until symptoms gone (1-3 days)
- Frequent recurrence
- Aciclovir 400bd long-term suppression
Cause of trichomoniasis
- Trichomonas vaginalis
Male symptoms of trichomoniasis
- Usually asymptomatic
Female symptoms of trichomoniasis
- 10-30% asymptomatic
- Profuse thin vaginal discharge - greenish, frothy and foul-smelling
- Vulvitis
Epidemiology of trichomoniasis
- Uncommon approx 100/year in Grampian
- More common in middle age women than some other STIs
Complications of trichomoniasis
- Miscarriage and pre-term labour
Diagnosis of trichomoniasis
- Metronidazole
Cause of anogenital warts
- HPV type 6&11 (occasionally 1)
- Different to strains that cause cervical cancer
Symptoms of anogenital warts
- Lumps with a surface texture of a small cauliflower
- Occasionally itching or bleeding especially perianal or intraurethral
Epidemiology of anogenital warts
- >90% have HPV infection at some point
- only 20% of those with wart causing strain get warts
- Drop in cases anticipated due to vaccine
Complications of anogenital warts
- None common
- Neonatal laryngeal papillomatosis
Diagnosis of anogenital warts
- Appearance
- Biopsy if unusual - to exclude intraepithelial neoplasia
Treatment of anogenital warts
- Popophyllotoxin (brans warticon and condyline), imiquimod (bran Aldara)
- Both home treatments
- Others - cryotherapy
- Bulkywarts - diathermy, scissor removal
Cause of syphilis
- treponema pallidum subspecies pallidum
Symptoms of syphilis
- Diverse
- Often entirely asymptomatic or mild symptoms which go unreported
- Primary - often ulcer
- Secondary - rash, mucosal ulceration, neuro symptoms, patchy alopecia
- Early latent - no symptoms but <2 years since caught
- Late latent - no symptoms but >2 years since caught
- Tertiary - neurological, cardiovascular or gummatous - skin lesions
Epidemiology of syphilis
- Approx. 20 cases/year in Grampian
- >90% cases MSM
Complications of syphilis
- Neurosyphilis - cranial nerve palsies are commonest, cardiac or aortal involvement
- Congenital syphilis (rare)
Incubation of syphilis
- 9-90 days until appearance of chancre but can be asymptomatic
Diagnosis of syphilis
- Clinical signs
- Serology for TP IgEIA, TPPA and RPR
- PCR on samples from an ulcer
Treatment of syphilis
- Early (<2 years and no neurological involvement)
- Benzathine penicillin 2.4 MU im once
- Or doxycycline 100mg bd po 2 weeks
- Late (>2 years) an no neurological involvement
- Benzathine penicillin 2.4 MU im weekly for 3 doses
- Doxycycline 100mg bd po 28 days
