Download STImed - School of Medicine

Sexually transmissible
infections
Dr Ursula Nusgen
SpR in Microbiology
St. James’s Hospital
Medical students don’t practise
safe sex on holiday
“Less than half of male students
interviewed at St George’s Hospital
Medical School, London, who have
sex with a new partner when on
holiday always use a condom.”
Family Practice (2003;20:93)
in STUDENTBMJ September 2003
NDSC Ireland, 2003
Increase of 9.4% for all STI’s in 2001
Of all notified cases in 2001, 61.5%
were in the 20 to 29 year old category
NDSC Ireland, 2004
Irish Times, 7/12/04 “Big increase in numbers
of syphilis and HIV”
Notified STIs increased by 8% from 2001 to
2002
10% increase in HIV cases
“Chlamydia is just rising and rising”
“The highest for any years on record”
NUI Galway
Acute lack of knowledge of relevant
issues related to student’s sexual health
Unawareness of individual risk of being
infected with an STI
Risky sexual behaviour
WESTfile, October 2003
Western Health Board
Department of Public Health
Microorganisms causing STI
Bacteria:
Viruses:
Neisseria gonorrhoeae
Chlamydia trachomatis
Treponema pallidum
Gardnerella vaginalis
Human immunodeficiency virus (HIV)
Herpes simples virus (HSV)
Hepatitis B virus, Hepatitis C virus
Human papillomavirus (HPV)
Trichomonas vaginalis
Protozoa:
Fungi:
Candida albicans
Ectoparasites: Phtirus pubis
Sarcoptes scabei
STI ?
STI
Often asymptomatic
Complications of untreated infections
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Chronic pelvic infection
Infertility
Ectopic pregnancy
Mother to child transmission
Recurrent infections
Systemic infection, many organs may be involved
Consequences may be longterm/lifelong
Early treatment important
STI
Correct diagnosis important
Get the right specimens the first time
Urethral/endocervical (NOT vaginal)
swabs, blood tests, others
Two or more STIs may be present at
a time
STI - Management
Appropriate treatment
simple treatment schedule
Risk reduction advise
Change risky behaviour
Limit number of partners
Safer sex practices (condoms)
Partner notification
STI - Symptoms
Unusual discharge from penis or vagina
Dysuria
Unusual blisters in the genital area
Itching or irritation in the genital area
Dyspareunia
Lower abdominal pain
OFTEN ASYMPTOMATIC
Urethritis
Gonococcal urethritis
Neisseria gonorrhoeae
Non-gonococcal urethritis (NGU)
Chlamydia trachomatis
(50-70% of cases)
Ureaplasma urealyticum
Mycoplasma genitalium
Other infectious causes
Non-infectious causes
Gonorrhoea
Neisseria gonorrhoeae (gonococcus)
Urethral/vaginal discharge
Pain (worse than chlamydia)
May disseminate
Or no symptoms
Complications of untreated infection
Gonorrhoea - urethritis
Gonorrhoea - cervical
Gonorrhoea - disseminated
Gonorrhoea
Specimens from urethra, uterine cervix,
rectum and pharynx
Specimens need to get to the lab quickly
Microscopy and culture
Treat: Penicillin, Ciprofloxacin, Ceftriaxone
Note: Increasing resistance worldwide
Gonorrhoea
Chlamydia trachomatis
Very common
Major cause of female infertility
Urethritis/cervicitis/NO SYMPTOMS
Special swabs from urethra/ endocervix
Diagnosis by molecular methods
(PCR or LCR)
Treatment: Azithromycin, Doxycycline
Chlamydia
Species
Hosts
Main disease Serotypes
C. trachomatis Humans
2 biovars
C. pneumoniae Humans
C. psittaci
Birds
C. abortus
Sheep/Goat
Oculogenital
D-K
Trachoma
A-C
LGV
L1-3
Lymphogranuloma venereum
Mainly in tropical countries
Papule/ulcer on genitalia
Regional lymphadenopathy (painful/discharge)
+/- painful bloody rectal infection
Compl.: permanent damage to bowels and genital
disfigurement (elephantiasis)
Diagnosis difficult, send to specialist laboratories
Early treatment with tetracycline, doxycycline,
erythromycin
Lymphogranuloma venereum
Syphilis
Treponema pallidum
Stage 1:
Stage 2:
Stage 3:
painless ulcer
Fever and rash,
condylomata lata
Gummata
Cardiovascular/Neurosyphilis
Syphilis – Stage 1
Syphilis – Stage 2
Syphilis – Stage 3
Syphilis - cardiovascular
Treponema pallidum
Syphilis - Diagnosis
Darkfield microscopy/immunofluorescence
stains from active lesions
Serology
standard non-treponemal tests
(VDRL, RPR)
specific treponemal antibody tests
Syphilis
Mother to child transmission
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Antenatal screening
Penicillin
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Different regimens according to stage of
disease
Genital Herpes
Herpes simplex virus (HSV1 > HSV2)
Lifelong latency
Periodic recurrences
THERE IS NO TREATMENT TO
ERADICATE THE LATENT STAGE
Herpes
Herpes - cervicitis
Herpes
Herpes
Prompt antiviral treatment to relieve systemic
symptoms (e.g. acyclovir)
Cannot prevent latency
Reactivations throughout life
Special viral swabs from active lesions for
diagnosis
Mother to child transmission
Condom may fail to prevent infection
Unpredictable, distressing, lifelong illness
Viruses with significant sexual
and non-sexual transmission
HIV
Transmission of HIV is enhanced
in the presence of other STIs
Hepatitis B
Genital warts
Human papilloma virus (HPV)
Mostly benign
HPV type 16 and 18 associated with
cancer of uterine cervix
Treatment: Chemical applications
(creams), surgery, cryotherapy,
electrosurgery, laser treatment
Genital warts
Molluscum contagiosum
Molluscum contagiosum
Trichomoniasis
Very common STI
Vaginal discharge (frothy, yellow)
Diagnosis by microscopy and culture
Treatment: Metronidazole
Trichomonas vaginalis
Phthirus pubis
Phthirus pubis - egg
Phthiriasis of pubic hair
Sarcoptes scabei
Scabies
Candidiasis
Candida - vaginitis
Candida - balanoposthitis
Bacterial vaginitis
Is not usually an STI
Inflammation of the vagina, with vaginal
discharge/irritation
Overgrowth of normal bacteria
Gardnerella vaginalis (may be an STI)
Bacterial vaginosis
Common
Vaginal discharge of fishy odour
Absence of inflammatory signs
Overgrowth of G. vaginalis /other anaerobes
Vaginal pH >6.0
Clue cells
Complications in pregnancy
Bacterial vaginosis
STI - Summary
More than one STI at a time
There may be no symptoms
Take correct specimens to get diagnosis right
Most can be cured if treated early
Longterm consequences if not treated
Mother to child transmission
Barrier contraceptives (condoms)
Partner notification
Recommended reading
Sexually Transmitted Diseases Treatment
Guidelines 2002
MMWR May 10, 2002/51 (RR06); 1-80
http:// www.cdc.gov