STIs Flashcards
what microorganism causes chlamydia
chlamydia trachomatis
outline the 3 main serovars that cause chlamydia
A-C causing trachoma (eye infection)
D-K causing genital infection
L1-L3 causing lymphogranuloma venereum
how does chlamydia present in men and women
men - asymptomatic or urethritis with dysuria and discharge
women - majority are symptomatic, post-coital or interenstrual bleeding, discharge, lower abdominal pain
if untreated what are the complications of STIs in men and women
men - proctitis and epididymitis
women - salpingitis, infertility and pelvic inflammatory disease
what type of bacterium is chlamydia
obligate intracellular bacterium
what is the best test for diagnosing chlamydia
NAAT - nucleic acid amplification test
how are specimens obtained from men and women for NAAT
women - vulvovaginal swab
men - first catch urine
men who have sex with men can have rectal swab if anoreceptive sex
the incubation period for chlamydia is 3-21 days, how many days after exposure should a chlamydia test be taken for a correct result
14 days
list some advantages and disadvantages of NAAT
less invasive specimens required
more sensitive than culture
can detect dead organisms, must wait 5 weeks for test of cure
what is the first line treatment for chlamydia
100mg doxycycline BDS for 7 days
what is the second line treatment for chlamydia
1g azithromycin for one day then 500mg daily afterwards
azithromycin is first line for pregnant women
outline some complications of chlamydia
transmission to neonate
reactive arthritis
Fitzhugh-Curtis syndrome
pelvic inflammatory disease
outline the features of reactive arthritis
anterior uveitis
urethritis
arthritis of knees, hands
outline the features of Fitzhugh-Curtis syndrome
liver capsule inflammation with perihepatic adhesions
improves on management of chlamydia
what is the partner notification period for chlamydia
if male urethral sex - 4 weeks
any other infection is 6 months
what organism causes gonorrhoea
neisseria gonorrhoea
what type of bacteria is gonorrhoea
gram -ve intracellular diplococcus
what are the symptoms of gonorrhoea
asymptomatic
urethritis, dysuria, mucopurulent discharge
pelvic pain, post-coital or intermestrual bleeding
how is gonorrhoea managed
IM ceftriaxone 1g stat
what is the partner notification period for gonorrhoea
male urethral - 2 weeks
any other infection - 3 months
where is lymphogranuloma venereum endemic
tropics, africa, south east asia
higher in men with HIV and hep C co-infection
how does lymphogranuloma venereum present
painless ulcerating papule on genitalia several weeks after infection
later the ulcer heals and regional lymphadenopathy develops
acute proctitis and perirectal abscess
outline the management of lymphogranuloma venereum
exclude syphilis and viral infections
doxycycline 100mg twice daily for 21 days
follow up until symptoms have resolved
what organism causes syphilis
treponema pallidum
what type of bacteria is syphilis
motile spirochete acquired through sexual contact
what are the 4 stages of syphilis
primary syphilis
secondary syphilis
latent
late stage
how does primary syphilis present
10-90 days after exposure
papule develops into painless, firm chancre at the site of exposure eg penis, endocervix or rectum
painless lymphadenopathy is association
how and when does secondary syphilis present
4-10 weeks after primary lesion
fever, malaise, arthralgia, sore throat
maculopapular non-itchy rash on palms and soles
snail track ulcers in oropharynx and genitalia
what is the term used to describe the maculopapular rash
condylomata lata
how does latent syphilis present
no symptoms
not usually infectious during this time
how and when does late stage syphilis present
can develop several years after primary infection
CVS, CNS and gummatous involvement
is treponema pallidum picked up in vitro culture
no
what is the best test for picking up treponema pallidum
dark field microscopy
what test for syphilis is best for monitoring response to therapy
rapid plasma reagin
how is syphilis managed
IM penicillin for 10 days
late stage, extend for another week
what is the partner notification look back period for syphilis
primary - 90 days
secondary - 2 years
which type of herpes simplex virus is most common
HSV 2
how does primary genital herpes present
systemic - fever, myalgia, headache
genital - multiple shallow ulcers which crust over after 10 days
tender inguinal lymphadenopathy
how is HSV diagnosed
usually clinical diagnosis
HSV PCR using swab of lesion or culture of virus lesion
how is HSV managed
symptomatic - saltwater bathing or warm bath, aciclovir 200mg 5 times a day
rest, analgesics and anti-pyretics
recurrent attacks of HSV are more or less severe
less severe - can be managed with simple measures
what strains of HPV are most likely to cause genital warts
types 6 and 11
how does HPV genital infection present
development of warts around fourchette, perianal region, penile shaft and vagina
how is HPV infection treated
local agents - podophyllin extract and trichloracetic acid for non-keratinising lesions
physical therapies such as cryotherapy, laser ablation and electrocautery are best for keratinising lesions
imiquimod also
how can HPV infection be prevented
HPV vaccine, protects against types 6, 11, 16 and 18
given to girls and boys before they are sexually active
what type of organism is trichomonas vaginalis
flagellated protozoon infection
how does trichomonas vaginalis present in men and women
men - urethral discharge, irritation and frequency
women - offensive discharge causing local irritation ad frothing
what test confirms diagnosis of trichomonas vaginalis
culture
what antibiotic is used to treat trichomonas vaginalis
metronidazole either single dose of 2g orally or 400mg twice daily for 7 days
what are the risk factors for developing candida infection
pregnancy and COCP use
use of broad spectrum antibiotics and corticosteroids
diabetes
immunosuppression - very florid infection
how does candidiasis present in women
pruritis of the vulva
red, fissured and sore external genitalia
altered vaginal discharge, curdy
what is the most likely organism to cause candida infection
candida albicans
more resistance types could be due to candida glabrata
what are the topical treatments used for candida infection
pessaries or creams containing clotrimazole (antifungal) 500mg
what are the oral treatments used for candida infection
fluconazole or itraconazole but only if topical therapy has failed
is it likely that candida infection is passed on sexually
unlikely
what causes bacterial vaginosis to develop
imbalance of normal bacteria, mixed flora of gardnerella, anaerboes and mycoplasma hominis
what is the main commensal bacteria of the vagina
lactobacilli
a pH of what is likely to be bacterial vaginosis
> 4.5
how does bacterial vaginosis present
homogenous, grey/white adherent discharge that has very strong odour
what is the main complication of BV in pregnancy
chorioamnionitis causing increases incidence of premature rupture of membranes
how is BV diagnosed
fishy odour on mixing discharge with 10% potassium hydroxide
microscopy
what cells are seen on BV microscopy
clue cells - granular appearance
how is bacterial vaginosis managed
metronidazole
recurrence rate is high
what organism causes pubic lice
Phthirus pubis
what is the main presenting complaint of pubic lice
itch
how is pubic lice treated
0.5% malathion lotion
1% permethrin
apply to whole body and wash off after 12 hours
