STD Flashcards
definition of STD
infection causewd by bacteria, virus, fungi or protozoa, which can be transmitted through sexual intercourse or close body contact with another infected person
bacterial causes of STI
- syphilis - treponema pallidum
- gonorrhoea - neisseria gonorrhoeae
- non-gonococcal urethritis- chalmydia trachomatis, ureaplasma urealyticum; mycoplasma genitalium
- chancroid- haemophilus ducreyi
- lymphogranuloma venereum (LGV) - chlamydia trachomatis
- granuloma inguinale - calymmatobacteria granulomatis
viral causes of STI
- ano-genital herpes - herpes simplex virus (HSV) type 1&2
- ano-genital warts- HPV
- viral hepatitis- Hep ABC
- AIDS/HIV- human immunodeficiency virus type 1&2
- Molluscum contagiosum- molluscum contagiosum virus
fungi causing STI
- vaginal candidiasis- candida albicans
note: not all due to sex
STI caused by parasites
- scabies- sarcoptes scabiei
2. pediculosis pubis- phthirus pubis
mode of transmission
- sex w infected person
- direct contact of broken skin with open sores, blood or genital discharge
- receiving contaminated blood
- mother to child transmission pregnancy (eg. syphilis, HIV) or childbirth (eg. chlamydia, gonorrhea, HSV) or breastfeeding (eg. HIV)
types of mother to child transmission
- placenta (syphilis, HIV)
- childbirth (chlamydia, gonorrhea, HSV)
- breast milk (HIV)
risk factors of STD
- unprotected sex
- number of sexual partner
- MSM
- prostitution (CSW)
- Illicit drug use
individual prevention methods
- abstinence and reduce sex partners
- barrier contraceptives (condoms lol)
- avoid drug abus and sharing needle (sheEEEesh)
- pre-exposure vaccinationas (HPV, Hep B or A)
- pre & post- exposure prophylaxis (HIV)
why management and prevent of STD is important
- reduce related morbidity, progression to complicated disease
- prevent HIV infection
- prevent serious complications in women
- STI are main preventable cause of infertility
- prevention of HPV reduced cervical cancer - protect babies (untreated STI associated with congenital and perinatal infections in neonates, premature deliveries and neonatal death or stillbirth)
what is gonorrhoea caused by
bacteria- Neisseria gonorrhoea (intracellular gram-neg diplococci)
how is gonorrhoea transmitted by
sexual contact, mother to child (childbirth)
diagnosis of gonorrhoea
gram stain of genital discharge, culture, NAAT, culture or urine PCR test
where can gonorrhoea infect
- urethritis
- cervicitis
- proctitis (rectum)
- pharyngitis
- conjunctivitis
- disseminated
symptoms presented in gonorrhoea
Males: purulent urethral discharge, dysuria, urinary frequency
Females: mucopurulent vaginal discharge, dysuria, urinary frequency
complication in untreated gonorrhoea
Males: epididymitis, prostatitis, urethral stricture, disseminated disease
Females: pelvic inflammatory disease, ectopic pregnancy, infertility, disseminated disease
Both: disseminated, skin lesion, tenosynovitis, monoarticular arthritis
first line management of uncomplicated gonococcal infections
- ceftriaxone 500 mg IM single dose (if >150kg, give 1g)
2. if chlamydial infection not excluded, treat for chlamydia with Doxycycline 100mg PO BD x 7d
alternative regimens for uncomplicated gonococcal
if ceftriaxone cmi
- gentamicin 240mg IM single dose + Azithromycin 2g PO single dose
- cefixime 800mg single dose (+ doxy 100mg BD x 7d if chlamydia not excluded)
management of sex partners in uncomplicated gonococcal infection
- sex partners in last 60d should be evaluated and treated
- if last sexual exposure >60d, most recent partner should be treated
- to minimise disease transmission, abstain for 7d after tx and resolution of symptoms if any
- abstain until all sex partners treated
what causes chlamydial infections
bacteria- Chlamydia trachomatis
diagnosis of chlamydia
NAAT or antigen detection
infection sites of chlamydia
similar to gonorrhea
- urethritis
- cervicitis
- proctitis (rectum)
- pharyngitis
- conjunctivitis
- disseminated
transmission of chlamydia
sex, childbirth
management of chlamydia
doxycycline 100mg PO BD x 7d
alternative chlamydia tx
- azithromycin 1g PO single dose
2. levofloxacin 500mg PO OD x 7d
why is erythromycin no longer recommended for chlamydial infection
GI side effect reduces adherence
management of sex partner for chlamydia
- partners in last 60d should be evaluated and treated, if last sex >60d, most recent partner should be treated
- abstain for 7d single dose/ completion of 7d therapy and resolution of symptoms if present
- abstain until all sex partners treated
causes of Syphilis
bacteria- treponema pallidum
transmission of syphillis
sex, placenta