STIs Flashcards
Bacterial STIs?
Chlamydia
Gonorrhoea
Syphilis
Viral STIs?
Genital warts (HPV)
Genital herpes
Hepatitis and HIV
Parasitic STIs?
Trichomonas vaginalis
Pubic lice
Scabies
Predisposing factors for candida infection?
Recent antibiotic therapy
High oestrogen levels
Poorly controlled diabetes
Immunocompromised patients
Presentation of candida infections?
Itchy
White vaginal discharge
Diagnosis of candida infection?
Clinical
HVS for culture
Treatment of candida infection?
Topical clotrimazol pessary or cream
Oral fluconazole
What is prostatitis?
Rare complication of UTI in men
Symptoms of prostatitis?
Symptoms of UTI +/- lower abdo/ back/ perineal/ penile pain
Tender prostate
Diagnosis of prostatitis?
Clinical signs
MSSU for c and s
Treatment of prostatitis ?
Ciprofloxacin for 28 days
Trimethoprim for 28 days of high c diff risk
What does lactobacillus produce?
Lactic acid
Hydrogen peroxide
What are normal vaginal flora?
Lactobacillus spp.
Strep viridans
Group B beta haemolytic streptococcus
Candida in small numbers
What is the normal pH of vagina?
pH4-4.5
What happens in bacterial vaginosis?
Replacement of normal vaginal flora with gardnerella vaginalis and species of anaerobic bacteria
What is vaginal discharge like in bacterial vaginosis?
Homogenous
May contain bubbles
What is the whiff test??
Adding 10% potassium hydroxide to discharge. +ve test elicits fishy odour
Does bacterial vaginosis have a positive or negative whiff test?
Positive
Treatment of bacterial vaginosis?
Metronidazole for 7 days
No point treating male partners
What is the commonest bacterial STI in UK?
Chlamydia
What organism is chlamydia caused by?
Chlamydia trachomatis
Does chlamydia stain with gram stain?
No - doesn’t have peptidoglycan in cell wall
Diagnosis of chlamydia?
14 days after exposure NAATs or PCR on: Males - first pass urine sample Females - HVS or vulvo-vaginal swab Rectal or throat swabs Eye swabs
Treatment of chlamydia?
Azithromycin if uncomplicated
Doxycycline
What organism is gonorrhoea caused by?
Neisseria gonorrhoea
What type of bacteria is neisseria gonorrhoea?
Gram negative diplococcus- looks like 2 kidney beans.
Diagnosis of gonorrhoea?
NAATs or PCR
Microscopy of urethral/ endocervical swabs
Culture on selective agar plates
Treatment of gonorrhoea?
IM ceftriaxone
Oral azithromycin
Advantages of NAATs / PCR over culture
Less invasive specimens required
More sensitive
Positive even if organisms dead
Takes hours instead of days
Disadvantages of NAATs/PCR over culture
Will detect dead organisms
Cannot test antibiotic sensitivities without culture so difficult to track antibiotic resistance
What organism causes syphilis?
Treponema pallidum - a spirochaete
Does treponema pallidum stain with gram stain?
No
How many stages are in the syphilis illness?
4
What are the stages of the syphilis illness?
Primary lesion - chancre - organism multiplies at inoculation site and gets into bloodstream
Secondary stage - large numbers bacteria circulating in blood with manifestations in different sites
Latent stage - low level multiplication of spirochaete in intima of small blood vessels
Late stage - CVS or neuro complications many years later
Diagnosis of syphilis?
Dark ground microscopy
Swab for PCR
Serology tests for antibodies
Treatment for syphilis?
Penicillin
What causes genital herpes?
Herpes simplex virus type 1 and type 2
How is genital herpes spread?
Genital/ genital contact or oropharyngeal/ genital contact
Diagnosis of genital herpes?
Swab deroofed blister for PCR
Treatment of genital herpes?
Aciclovir
Pain relief
What does trichomonas vaginalis cause?
Vaginal discharge and irritation
Diagnosis of trichomonas vaginalis?
HVS for microscopy
PCR
Treatment for trichomonas vaginalis?
Oral metronidazole
How long does a make louse live for?
22 days
How long does a female louse live for?
17 days
Treatment of pubic lice?
Malathion lotion
Presentation of chlamydia in females?
Post coital or intermenstrual bleeding
Lower abdo pain
Dysparaneuria
Mucopurulent cervilitis
Presentation of chlamydia in males?
Urethral discharge Dysuria Urethritis Epididymo-orchitis Proctitis
Complications of chlamydia?
PID
Tubal damage - can lead to infertility and ectopic pregnancy
Chronic pelvic pain
Transmission to neonate
Adult conjunctivitis
Sexually acquired reactive arthritis (SARA) / reiters syndrome
Fitz Hugh Curtis syndrome
Incubation period of gonorrhoea in men - (urethral infection )
About 2-5 days
What is the risk of transmission of gonorrhoea from female to male?
20%
What is the risk of transmission of gonorrhoea from male to female?
50-90%
Presentation of gonorrhoea in males?
<10% asymptomatic
Urethral discharge
Dysuria
Pharyngeal/rectal infection
Prevention of gonorrhoea in females?
<50% asymptomatic Increased/ altered vaginal discharge Dysuria Pelvic pain Pharyngeal / rectal infection
Lower genital tract complications of gonorrhoea?
Bartholinitis Tysonitis Periurethral abscess Rectal abscess Epididymitis Urethral stricture
Upper genital tract complication of gonorrhoea?
Endometritis PID Hydrosalpinx Infertility Ectopic pregnancy Prostatitis
Classification of genital herpes ?
Primary infection
Non-primary first episode
Recurrent infection
Presentation of genital herpes primary infection ?
Blistering and ulceration of external genitalia Pain External dysuria Vaginal or urethral discharge Local lymphadenopathy Fever and myalgia
Incubation period of syphilis primary infection
3-6 days
Duration of syphilis primary infection?
14-21 days
What is the most common viral STI in UK?
HVP
How many of the 170 HVP infect anogenital epithelium?
40
List some low risk HPV types?
6 11 42 43 44
List some high risk HPV types?
16 18 31 33 35 45 51 52 66
What is the HPV incubation period ?
3 weeks - 9 months
Treatment of HPV?
Podophyllotoxin Imiquimod Cryotherapy Electrocautery HPV vaccination
Incubation period of primary syphilis?
9-90 days - mean 21 days
Incubation period of secondary syphilis?
6 weeks - 6 months
Presentation of secondary syphilis?
Skin - macular, follicular or pustular rash on palms and soles Lesions of mucous membranes Generalised lymphadenopathy Patchy alopecia Condylomata lata
What is condylomata lata?
Highly infectious lesion in syphilis
Exudes a serum teeming with treponemes
