Microbiology: Infections in O&G Flashcards
How does the pH of the vaginal throughout a woman life & why does this occur?
At puberty under the influence of oestrogen the vagina changes from simple cuboidal to squamous epithelium and lactobacilli become the predominant organism, this drops pH to 3.5-4.5. After menopause changes back and pH rises to 7.0
What % of vaginal candidiasis are due to C.albicans?
80-90%
remaining C glabrata, C krusei C tropicalis
How many woman are colonised with candida (mostly asymptomatic)?
How does this change in pregnancy
20%
40%
How does the Tx of candida change in pregnancy?
Do not use oral azoles
Creams or pessaries
How can genuine recurrent infection with candida be Tx
6 month weekly fluconazole
Boric acid intravaginally
Does candida effect pregnancy?
no
What is the comment of cause of abnormal discharge? Prevelance in UK?
BV 12%
What is the pathophysiology BV
Anaerobic organism normally in low concentration increase, taking over the predominant lactobacilli. pH rises from 4.5 tp 7.0
gardnerlla vaginalis, bacteroides,..
What is the Amsel criteria to Dx BV?
vaginal pH >4,5
fish smell on addition of alkali
characterise discharge on examination
clue cells on microscopy
Tx of BV
Metronidazole tablets or cream
Clindamycin cream
Complications of BV in pregnancy
2nd trimester miscarriage, preterm delivery
Transmission of Trichomonas
Sexually transmitted, asymptomatic for many months
Clinical features of trichomonad
vulvovaginitis
green/yellow discharge +/- offensive smell
punctuate haemorrhage on cervix ‘strawberry’
Trichomoniasis is detected on what swab?
NAAT
Tx of trichomoniasis>
metronidazole
partner should also be Tx
Complications of trichomoniasis in pregnancy
increased risk of preterm birth but asymptomatic tx not shown to improve outcome
Tx for pubic lice and scabies
Topical malathion or permethrin
Tubal factor infertility is how common after PID (1 episode, 3 episodes)
Tubal infertility rate following 1 episode PID 12%
Tubal infertility rate following 3 episodes PID 50%
How common is chronic pelvis pain after PID
15%
Chlamydia and gonorrhoea account for what % of PID
25-50%
What % of women of childbearing age are infected with chlamydia
10% most common STI
highest <25
What % of people infected with chlamydia are asymptomatic?
50% & 80%
What form of chlamydia can cause severe proctitis?
Lymphogranuloa Venereum (LGV)
What type of bacteria is chlamydia?
Obligate intracellular bacteria
What abx are effective in uncomplicated chlamydia?
Azithromycin
Doxycycline
Ofloxacin
erythromycin
What % of women of child baring age are infected with gonorrhoea?
1%
What % of people infected with gonorrhoea are asymptotic?
women 50%
men 10%
What is the appearance of gonorrhoea on microscopy?
Gram -ve intracellular diplococci
reccommeneded Tx fo gonorrhoea?
Single dose azithryomycin 1g PO (or doxycycline)
Ceftriaxone 500mg IM
How does cervicitis present?
Post coital bleeding
purulent vaginal discharge
Chronic cervicitis can lead to what?
nabothian follicles (cysts) and scarring
What clinical features indicate PID
- hx pelvic pain and deep dyspareunia
- cervical motion tenderness
- lower UTI
- pyrexia
- adnexal ass (20%)
clinical dx 70-80% accurate
Gold standard Ix for diagnosis for PID
laproscopy
Complications of PID
Tubal factor infertility
Abscess
Adhesions - chronic pelvic pIN
pelvic peritonitis
Standard Abx for PID
IM ceftriaxone 500mg
Doxycycline 200mg BD - 14days
Metronidazole 400mg BD - 14days
What condition caused by chlamydia/gonnorea present with fever & RUQ pain
Fitz-high-curtis syndrome - requires 3 weeks abx
Name of disseminated chlamydia that presents with asymmetrical oligoarthritis affecting large joints of lower limb, uveitis and a rash (similar to psoriasis)
Reiter syndrome
Associated with HLA B27
How does disseminated gonorrhoea present?
Septic oligoarthritis effecting hands and wrists + scanty papular rash
How does infection with chlamydia/gonorrhoea effect pregnancy/newborn?
Pregnancy: chorioamnitis and 2-3 high risk of preterm birth
Infant: Opthalmia neonatorum (may lead to corneal scarring and blindness), in chlamydia may develop pneumonitis
What are the symptoms of genital tuberculosis?
In most cases, the disease is asymptomatic, infertility is the most common.
Other symptoms reported are menstrual irregularities and abnormal vaginal discharge.
Pelvic actinomycosis is associated with what iatrogenic cause?
IUCD
Syphilis is caused by which bacteria?
Treponema Pallidum
How & when does primary syphilis present?
Painless chancre and lymphadenopathy 3-90 days (women do no always see the chancre as often on cervix)
How & when does secondary syphilis present?
Widespread rash typically affecting hands and soles of feet.
Wart lesions (condyloma latum) of mucus membranes
within 6 months
What occurs after secondary syphilis?
Latent phase
No symptoms, +be serological testing, can transmit
How & when does tertiary syphilis present
Gummas OR
Neurosyphilis OR
Cardiovascular syphilis
3+ year after primary infection
Main Abx to Tx syphilis?
Penicillins
By what gestation must syphilis be treated to prevent late congenital symphilis?
20 weeks
How can syphilis effect the fetus
Fetal death
long term
- 8th nerve deafness, insteitial keratitis, abnormal teeth
Infectious causes of genital ulcer diease
Herpes simplex Primary syphilis Lymphogranuloma venereum chancroid donovanosis HIV
What is chancroid
Chancroid is a bacterial sexually transmitted disease (STD) caused by infection with Haemophilus ducreyi. It is characterized by painful necrotizing genital ulcers that may be accompanied by inguinal lymphadenopathy.
What is granuloma inguinale (donovanosis)
Granuloma inguinale is a rare sexually transmitted disease caused by the bacteria Klebsiella granulomatis. It leads to chronic inflammation and scarring of the genitals. Granuloma inguinale typically causes a painless, red lump on or near the genitals, which slowly enlarges, then breaks down to form a sore.
What are the common low risk HPV strains responsible for 90% genital warts?
HPV 6 & 11
What are the common high risk HPV stains found in 70% of cervical cancer cases?
HPV 16&18
Lifetime risk of infection with HPV?
80%
Lifetime risk of cancer if infected with HPV 16 or 18
5% in unscreened
1-2% in screened women
Gardasil vaccinate against which strains
6,11,16,18
Tx of genital warts
Physical methods - weekly cryotherapy
podophyllotoxin applied BD for 3 days
imiqimod TDS
On average if untreated how long does HIV take to develop into AIDS
10 years
How is HIV diagnosed, the monitored
Antibody to gp120 or p24 antigen
Monitored by measuring CD4 lymphocytes
Conc of Viral RNA
Treatment of HIV
1) Antiretrovirals → NRTI + NNRTI or protease inhibitor
2) Prophylaxis against opportunistic infections
How often does vertical transmission happen in pregnancy of HIC if no interventions take place?
25-40%
With antiretrovirals 1.2%
How often does transmission throughou the breastmilk occur?
15%
Breastfeeding should be avoided regardless of viral load
Can women with HIV give birth vaginally?
Depend on 36 week viral load
<50: Yes
50-400: consider other risk factors
>400: ELCS or if taking zidovudine mono therapy
When is infant Antiretroviral therapy(ART) given?
Depends on which risk group
Very low risk: 2 weeks zidovudine
Low risk: 4 week zidovudine
high risk: PEP
How often should women with HIV have cervical cytology?
Yearly - HPV flourishes and higher risk cervical cancer
What contraception can be offered to women taking antiretrovirals?
Depot infection
IUCD
What can be offered to women how experience frequency UTI after sexual intercourse?
3-6 months of low dose abx either every night or after intercourse (trimethoprim 100mg on)
Which bacteria can cause a more severe puerperal fever?
Group A strep
How many women a year die from puerperal sepsis?
10
