Genital Infections Flashcards
Definition of recurrent vulvovaginal candidiasis
At least 4 episodes of infection per year and/or a positive microscopy of moderate to heavy growth of C. albicans
Prevalence of C. albicans in asymptomatic women
30-40%
Indications for treatment of vulvovaginal candidiasis
Only if symptomatic
Pregnancy is not an indication for treatment - no evidence of adverse outcomes and oral imidazoles are contraindicated in pregnancy
Causes of vulvovaginal candidiasis
80-90% C. albicans Non-albican species (tend to have similar symptoms but more severe and/or recurrent) - C. tropicalis - C. glabrata - C. krusei - C. parapsilosis
Factors pre-disposing to vulvovaginal candidiasis
Pregnancy High-dose COCP Immunosuppression Broad spectrum antibiotics Diabetes Hormone Replacement Therapy HIV
Microbiology of C. albicans
Diploid fungus
Gram positive spores + long pseudohyphae
Common commensal in gut flora
Diagnosis of C. albicans
Vaginal swab Gram stain:
Gram +ve spores and long pseudohyphae
Numerous polymorphs
Abnormal bacterial flora (resembling bacterial vaginosis)
Management of uncomplicated vulvovaginal candidiasis
Avoid soaps, perfumes, synthetic underwear
Change from high to low dose COCP or to progesterone only if recurrent
Either a single treatment or a course of several applications/pessaries
Local topical azole
Oral: fluconazole 150mg single dose
OR clotrimazole single 500mg pessary or 100mg pessaries over 6 days
Maintenance treatment for recurrent vulvovaginal candidias
150mg Fluconazole weekly for 6 months
OR
weekly topical clotrimazole 500mg for 6-8 weeks
Evidence for use of oral or vaginal lactobacillus or yeasts for vulvovaginal candidiasis
NO EVIDENCE. not recommended
Definition of trichomonas vaginalis
A severe vulvovaginitis caused by the protozoan trichomonas that is usually sexually transmitted and commonly recurs if male partner is not treated
Clinical features of trichomonas vaginalis
Vulval soreness and itching
Foul smelling frothy yellowish green discharge
Dysuria
Abdominal discomfort
Strawberry cervix - punctate haemorrhages
May be asymptomatic carrier
Confirming diagnosis of trichomonas vaginalis
MCS of vaginal swab:
- cone-shaped, flagellated organism with terminal spike
- motile protozoa - i.e. amoeboid motion with flagella waving if looking at under microscope
Management of trichomonas vaginalis
Metronidazole - 2g single oral dose
Ensure screening and treatment of partners too
Normal vaginal pH
4.5 i.e. slightly acidic environment
Definition of bacterial vaginosis
A common condition of the vagina characterised by the presence of foul-smelling vaginal discharge in the absence of obvious inflammation. It is caused by an increase in the vaginal pH secondary to a change in the flora of the vagina from normal lactobacilli to predominantly anaerobes
Risk factors for bacterial vaginosis
Sexual activity Woman-woman sexual intercourse HSV-2 infection HIV infection Vaginal douching Cigarette smoking
Common species involved in bacterial vaginosis
Gardnerella vaginalis
Mobilinicus spp.
Mycoplasma hominis
Bacteroides spp.
Clinical features of bacterial vaginosis
Fishy malodorous vaginal discharge
More prominent during and following menstruation
Creamy or greyish-white vaginal discharge adherent to vaginal wall
May be asymptomatic carrier
Diagnostic criteria for bacterial vaginosis
Amsel criteria:
- Presence of clue cells on microscopic examination of vaginal swab
- creamy greyish white discharge seen on naked eye examination
- Vaginal pH >4.5
- Positive whiff amine test (release of characteristic fishy odour on addition of alkali: 10% potassium hydroxide)
at least 3 of the 4 to make a diagnosis
What is a clue cell
An epithelial cell studded with adherent coccobacilli that gives the cell a stipple appearance - indicator of bacterial vaginosis
Management of bacterial vaginosis
ORAL 400mg metronidazole BD 5 days 2g metronidazole single dose 300mg clindamycin BD 7 days (preferred in pregnancy) Tinidazole 2g orally single dose OR TOPICAL METRONIDAZOLE OR CLINDAMYCIN
Microbiology of neisseria gonnorhoea
Gram-negative intracellular diplococcus
Has affinity to infect the mucous membranes of the genital tract - columnar and cuboidal epithelium in endocervical and urethral mucosa
Can also infect the rectal and oropharyngeal mucous membrane
Clinical features of gonorrhoea in a symptomatic females
Increased discharge
Lower abdo/pelvic pain
Dysuria with urethral discharge
Proctitis with rectal bleeding, discharge and pain (if anal sex)
Endovcercvical mucopurulent discharge and contact bleeding
Mucopurulent urethral discharge
Pelvic tenderness with cervical excitation
Clinical features of gonorrhoea in symptomatic males
Dysuria
white, yellow or green urethral discharge
Painful or swollen testicles (less common)
Rectal infection: discharge, itching, soreness, bleeding, painful bowel movements
Diagnosis of gonorrhoea
Endocervical swabs/swabs from symptomatic areas
- Gram-negative intracellular dipplococci
OR
nucleic acid amplification tests: can test samples from urine and lower vagina
management of gonorrhoea
Contact tracing
Antibiotics:
in urban Australia: Ceftriaxone 500mg IV or IM + Azithromycin 1g orally (single doses)
In remote areas (less penicillin resistance):
amoxycillin 3g, probenecid 1g, azithromycin 1g all as single oral doses
Groups at highest risk of STIs
Young people under 25 Men who have sex with men People who inject drugs Sex industry workers Known contacts of someone with an STI
5 Ps of sexual history taking
Partners Practices Protection from STIs Past history of STIs Prevention of pregnancy (contraception)
Chlamydia trachomitis serotypes responsible for genitourinary infection
Serotypes D-K
A-C infect the conjunctiva and cause trachoma
Clinical features of chlamydia in women
Majority asyptomatic Increased vaginal discharge Lower abdominal pain Postcoital bleeding Intermenstrual bleeding Mucopurulent cervical discharge with contact bleeding Dysuria with urethral discharge
Clinical features of chlamydia in men
Mucoid or watery urethral discharge - often clear and only seen upon milking the urethra
Dysuria
Incubation period approx 5-10 days i.e. longer than that of gonorrhoea
Gold standard investigation for diagnosis of chlamydia
Nucleid acid amplificationt test (NAAT)
- first catch urine sample, low vaginal swab or endocervical swab
Microscopy is not useful for the diagnosis of chlamydia
Management of uncomplicated chlamydia in women
Azithromycin 1g orally single dose
OR
Doxycycline 100mg orally BD for 7 days
Management of chlamydia in men
doxycycline 100mg BD for 14-21 days
OR
Azithromycin 1g orally stat, repeated 1 week later if concern of adherence
Management of STI suspected epididymo-orchitis without identified organism
Treat for both chlamydia and gonorrhoea: Ceftriaxone 500mg IM or IV PLUS Azithromycin 1g orally stat PLUS Doxycycline 100mg BD 14 days or Azithromycin 1g 1 week later
Factors affecting recurrent infection in genital herpes
More likely to occur in HSV2 (4x per year) v HSV1 (1x per year)
Longer duration and greater severity of primary infection
Recurrence rates highly variable
Management of genital herpes primary infection
Oral Aciclovir, famciclovir of valaciclovir for 5 days
begin treatment as soon as clinical diagnosis is made
up to 10 days of treatment may be needed for severe disease
Management of recurrent genital herpes
Most patients will not require treatment with mild infrequent recurrences
Episodic treatment if infrequent and moderate severity
Short courses started with onset of prodromal symptoms or with onset of lesions
Aciclovir, famciclovir or valaciclovir for 1-5 days accordingly
Suppressive therapy: indicated for frequent severe recurrences, reduces recurrence by 70-80%
Aciclovir, famciclovir, (BD) valaciclovir (once daily), reassess at 6 months
Can safely be continued long-term
Diagnosis of genital herpes
Confirm clinical diagnosis with PCR, viral culture of immunofluoresence of vesicular fluid ideally
serology may be useful if repeat swabs negative, patients with partners who have genital herpes, risk of new infection in pregnancy
Management of gonorrhoea
500mg IM ceftriaxone
Gonorrhoea and chlamydia contact tracing
Gonorrhoea: sexual partners from past 2 months
Chlamydia: sexual partners in last 6 months
