STI Flashcards
What is the main bacteria of vaginal flora?
lactobacillus
what is the role of lactobacillus?
prevent pathological prevention by producing lactic acid and H202
what type of gram stain is chlamydia?
gram negative bacterium
what is the cause of chlamudia?
chlamydia trachomatis
what are the serological groupings of chlamydia and their associated infections:
A-C: Eyes - trachoma
D-K: genital
L1-L3: Lymphogranuloma venerum (seen in HIV patients, features: genital ulcers+ painful inguinal lymphadenopathy)
what are the clinical features of chlamydia?
asymptomatic in majority of women cases and half of mens
men:
urethral discharge
dysuria
women:
cervicitis (discharge, bleeding)
dysuria
what are the potential complications of chlamydia?
PID
endometritis
Epididymitis
infertility
increased incidence of ectopic pregnancies
how do you diagnose chlamydia?
screening:
open to all men and women 15-24 years old
Investigation:
women:
NAATs = investigation of choice
alternatives to NAATs: vulvovaginal swab or cervical swab
men:
Urine test is first line
how do you manage chlamydia?
doxycycline (7 day course) 1st line
azithromycin used if contraindicated
pregnant:
azithromycin (1st choice)
can also used erythromycin or amoxicillin
for women and asymptomatic men:
contact all partners of past 6 months
men with urethral symptoms:
all contacts since and in the 4 weeks prior to symptoms
what is the cause of gonorrhoeae?
gram negative diplococcus Neisseria gonorrhoeae
how long is the incubation of gonorrhoeae?
short 2-5 days
what are the clinical features of gonorhoeae?
asymptomatic in less than 10% of men.
men:
smelly
yellow discharge
associated dysruia
can also cause anal discharge
women:
Increased or altered vaginal discharge
Lower abdominal pain
Dysuria
n.b. rectal and pharyngeal infection is usually asymptomatic
how do you diagnose gonorrhoeae?
men: first pass urine
women: vulvovaginal swab
NAAT - tests for chlamydia and gonorrhoea
how do you manage gonorrhoeae?
1st line ceftriaxone IM 1g
use oral cefixime 400mg 1 dose + oral azithromycin 2g 2 dose
what are the complications of gonorrhoeae?
uretheral strictures
epididymitis
salpingitis
what are the key features of disseminated gonococcal infection?
tenosynovitis
migratory polyarthritis
dermatitis
what causes syphillis?
treponema pallidum
what are the clinical features of syphillis?
1.primary 9-90 days:
painless genital ulcer - chancre
2.secondary (6 weeks - 6 months):
mouth ulcers
generalised maculo-papular rash
condylomata lata - highly infective, wart like lesions on genitals
Flu like symptoms - arthlagia, malaise, fever, sore throat
3.Latent:
Asymptomatic
Early: <2 years after infection
Late: >2 years after infection
from late latent and beyond considered non infectious
- Tertiary:
Gummatous syphilis:
Gumma — granulomatous lesions with a necrotic centre.
Can develop anywhere but most often affect skin and bone.
cardiovascular syphillis:
Cardiovascular disease — often due to vasculitis and chronic inflammation of the aortic vasa vasorum.
Neurosyphilis:
Tabes dorsalis (inflammation of spinal dorsal column/nerve roots)
argyl robertsol pupil - bilateral small pupils that reduce in size on a near object
how do you diagnose syphillis?
Non treponemal tests:
non specific for syphilis - false positive risks
e.g. rapid plasma reagin
venereak disease research laboratory
treponemal specific tests:
TP EIA (T pallidum enyme immunoassay)
Pos non treponemal + pos treponemal test= consistent with active syphilis
pos Non treponemal + negative tepronemal = false positive
Neg non treponemal + pos treponemal= successfully treated syphilis
how do you manage syphillis?
IM benzathine penicillin - 1st line
alternative= doxycycline
jarisch- herxheimer reaction sometimes seen following treatment ( rash, fever, tachycardia)
give antipyretics
what is herpes?
an enveloped DNA virus
what are the two strains of Herpes?
HSV-1 - causes most of oral cases. causes 50% of genital infections
HSV-2 - causes 50% of genital infection. 10% of oral cases
what are the clinical features of Herpes simplex?
- primary infection: may present with a severe gingivostomatitis
- cold sores
- painful genital ulcerations
Recurrent genital herpes occur due to reactivation of pre-existent HSV infection after a latent period.
People typically present with painful blisters or ulcers unilaterally in a single anatomical site, and prodromal tingling and burning symptoms may precede the development of lesions by hours or days.
Systemic symptoms such as fever and malaise are less common than initial episodes, and recurrent attacks are usually less severe, lasting between 5–10 days.
what are the risk factors of HSV?
Age — peak incidence of HSV is in people aged 15–24 years.
Previous history of STIs.
A high number of lifetime sexual partners.
More than one partner in the last year, or a recent new partner.
Early age of first sexual intercourse.
Unprotected sexual intercourse.
Men who have sex with men.
Female sexual partners of men who have sex with men.
HIV infection.
People who are immunocompromised.
