Genitourinary Medicine - WH + GP Flashcards
Define Bacterial Vaginosis? What bacteria cause it?
Overgrowth of anaerobic bacteria in the vagina due to a loss of commensal lactobacilli (recent antibiotics or excessive vaginal cleaning)
Lactobacilli produce lactic acid which maintains a low vaginal pH (below 4.5) and prevents other bacteria from overgrowing. When there are reduced numbers of lactobacilli in the vagina, the pH rises and allows anaerobic bacteria to grow:
- Gardnerella vaginalis (most common)
- Mycoplasma hominis
- Prevotella species
Presentation of Bacterial vaginosis
The standard presenting feature of bacterial vaginosis is a fishy-smelling watery grey or white vaginal discharge. Half of women with BV are asymptomatic.
Itching, irritation and pain are not typically associated with BV and suggest an alternative cause or co-occurring infection.
Microscopy of a high vaginal swab (speculum) shows clue cells. What is the diagnosis?
Bacterial vaginosis gives “clue cells” on microscopy. Clue cells are epithelial cells from the cervix that have bacteria stuck inside them, usually Gardnerella vaginalis.
Can also test for higher vaginal pH but I doubt this is actually done.
Rx for BV
Metronidazole is the antibiotic of choice for treating bacterial vaginosis. Metronidazole specifically targets anaerobic bacteria. This is given orally, or by vaginal gel.
Asymptomatic BV does not usually require treatment.
Tom Tip: Avoid alcohol with metronidazole - Alcohol and metronidazole can cause a “disulfiram-like reaction”, with nausea and vomiting, flushing and sometimes severe symptoms of shock and angioedema.
Complications of BV and clamydia in pregnancy are almost indentical?
All:
- miscarriage
- preterm delivery
- PROM
- chorioamnionitis
- low birth weight
- post-partum endometritis
- clamydia specific - neonatal pneumonia.conjuctivitis
What causes vaginal thrush? (inc risk factors)
Vaginal infection with candida yeast (most commonly candida albicans). Cadndida may asymptomatically colonise the vagina but then progress to infection when the right environment occours:
- increased oestrogen (pregnancy)
- broadspectrum antibiotics (like BV)
- immunosupression/diabetes
A female presents with:
- Thick, white discharge that does not typically smell
- Vulval and vaginal itching, irritation or discomfort
Diagnosis?
How would you confirm the diagnosis?
Thrush - Vaginal Candidiasis
A charcoal swab with microscopy can confirm the diagnosis.
Managment of vaginal candiasis
Treatement is with antifungal medications. Inital management can be given in one of three ways
- intravaginal clotrimazole cream at night
- **clotrimazole pessary **
- a signle dose of oral fluconazole
Canesten Duo is a standard over-the-counter treatment worth knowing. It contains a single fluconazole tablet and clotrimazole cream to use externally for vulval symptoms.
Ix for clamydia
Nucleic acid amplification tests (NAAT) are used to diagnose chlamydia and gonorrhoea. Rather than using microscopy these are checked directly for the DNA and RNA of the organism.
- Vulvovaginal swab
- Endocervical swab (speculum)
- First-catch urine sample (in women or men)
- Urethral swab in men
- Rectal swab (after anal sex)
- Pharyngeal swab (after oral sex)
Officially charcoal swab isnt mentioned but i think it is taken, in case its is gonorheaea to help guide antibiotic choice.
A women presents with abnormal vaginal discharge, pelvic pain, dyspareunia, dysuria and post-coital bleeding. Diagnosis? How does the presentation differ from another key differential?
Answer - Chlamydia
Presentation of Chlamydia in women:
Abnormal vaginal discharge
Pelvic pain
Abnormal vaginal bleeding (intermenstrual or postcoital)
Painful sex (dyspareunia)
Painful urination (dysuria)
Presentation of Gonorrhea in women:
- odourless purulent discharge, possibly green or yellow
- dysuria
- pelvic pain
SO BASICALLY CLAMYDIA CAN CAUSE ABNORMAL BLEEDING, Gonorhea dischare is purulent, odourless and possibly green/yellow.
In men (these are the same for both chlamydia and gonnorhea)
- urethral discharge
- dysuria
- epidydymo-orchitis
A large number of chlamydia cases are asymptomatic (50% in men and 75% in woman). Infection with gonorrhoea is more likely to be symptomatic than infection with chlamydia. Only 10% of men and 50% of women are asymptomatic.
Rx for clamydia?
In pregnancy?
First-line for uncomplicated chlamydia infection is Doxycycline 100mg twice a day for 7 days.
Pregnancy:
- Doxycycline is contra-indicated in pregnancy and breastfeeding. Alternatives include Azithromycin and erythromycin.
- a test of cure should be used in pregnancy
What is clamydial conjuctivitis
Chlamydia can infect the conjunctiva of the eye. Conjunctival infection is usually as a result of sexual activity, when genital fluid comes in contact with the eye, for example, through hand-to-eye spread. It presents with chronic erythema, irritation and discharge lasting more than two weeks. Most cases are unilateral.
Chlamydial conjunctivitis occurs more frequently in young adults. It can also affect neonates with mothers infected with chlamydia.
Gonococcal conjunctivitis is a crucial differential diagnosis and should be tested. In neonatas, gonococaal conjuntivitis (contracted during birth) is a medical emergency associated with sepsis and blindness.
What is lyphogranuloma venereum?
Usually occours in MSM, lymphogranuloma venereum is a condition affecting the lyphoid tissues around the site of a clamydia infection.
It occours in three stages with a painless ulcer in the rectum, vagina or penis, followed by inguinal lymphadenitis (painful inflammation of lymph nodes), followed by proctitis.
Rx is with Docycycline (just like uncomplicated clamydia) but for 21 days (uncomplicated is 7 days).
Ix for Gonorrheae
Like chlamydia, NAAT testing is used to test for gonorrhea:
- endocerival swab
- vulvovaginal
- urethral
- rectal
- pharyngeal
ALSO a charcoal swab for microscopy, culture and antibiotic sensaitivities.
NAAT test do not provide any information about the specific bacteria and their antibiotic sensitivities and resistance. This is why a standard charcoal swab for microscopy, culture and sensitivities is so essential, to guide the choice of antibiotics to use in treatment.
Rx for Gonorrhea
- A single dose of intramuscular ceftriaxone 1g if the sensitivities are NOT known
- A single dose of oral ciprofloxacin 500mg if the sensitivities ARE known
Unlike clamydia, because of high antibitoic resistance, a test of cure is performed.
Key - Ceftriaxone is also safe in pregnancy.
What is pelvic inflammatory disease?
Causes?
Pelvic inflammatory disease (PID) is inflammation and infection of the organs of the pelvis, caused by infection spreading up through the cervix. It is a significant cause of tubular infertility and chronic pelvic pain. It includes endometritis, salpingitis, oophoritis, parametritis.
Most cases are caused by STI accending:
- Neisseria gonorrhoeae tends to produce more severe PID
- Chlamydia trachomatis
- Mycoplasma genitalium
Less commonly caused by non-STIs:
- Gardnerella vaginalis (associated with bacterial vaginosis)
- Haemophilus influenzae (a bacteria often associated with respiratory infections)
- Escherichia coli (an enteric bacteria commonly associated with urinary tract infections)
