O&G JC105: Vaginal Discharge: Obstetric And Gynaecological Infections

Question 1

Natural defence mechanisms

Answer 1

1. ***Apposition of labia and vaginal walls
2. Natural resistance to infection of stratified squamous epithelium in lower genital tract
3. Vaginal flora (esp. ***Lactobacilli) —> makes vagina acidic
4. ***Vaginal acidity (pH 3.5-4.5)

Question 2

Factors affecting defence mechanisms adversely

Answer 2

1. ***Menstrual cycle
   - alkalinity of secretions around menses –> higher chance of infection
2. ***Pregnancy and Puerperium
   - ↑ in vaginal pH
   - ↑ estrogen level –> ↑ glycogen content in vaginal secretions
   - trauma at delivery
   - lochia: alkaline
3. Other medical conditions
   - **DM
   - **Antibiotics use

Question 3

***Non-infectious causes of vaginal discharge

Answer 3

1. Physiological
   - Watery, Mid-cycle (during ovulation) (SpC Revision)
   - Thicker after ovulation
2. Cervical ectropion
3. Foreign bodies (e.g. IUCD, ring pessary)
4. Vulval dermatitis
5. Benign / Malignant tumours of genital tract

Question 4

***Infectious causes of vaginal discharge

Answer 4

1. Non-STD
   - Candidiasis
   - Group B Streptococcus
   - Bacterial vaginosis (overgrowth of bacteria naturally found in the vagina, which upsets the natural balance)
2. STD
   - Chlamydia trachomatis
   - Neisseria gonorrhoea
   - Trichomonas vaginalis (parasite)

Question 5

History taking of vaginal discharge

Answer 5

1. History of present illness
   - **Timing of discharge
   - **Smell
   - Associated symptoms e.g. fever, abdominal pain, pruritus
2. Contraception
   - e.g. IUCD
3. Past medical health
   - e.g. DM
4. Obstetrics history
5. ***Cervical smear
   - up-to-date?
   - result normal?

Question 6

Physical examination of vaginal discharge

Answer 6

1. Nature of discharge
2. Local lesions of lower genital tract that explain vaginal discharge

Question 7

Approach to vaginal discharge

Answer 7

1. History taking
2. Physical examination
   –> Differentiate ***Physiological vs Pathological discharge
3. Investigations + Treatment according to DDx
4. Prevent recurrence

Question 8

Candidiasis (念珠菌症)

Answer 8

Causative organism: **Candida albicans (Gram +ve yeast-like fungus)
- incidence in pregnant women: 10-16%
- prevalence in healthy young women: 20-25%
- recurrence: <5%
- **NOT a STD!!!

Question 9

Clinical features of Candidiasis

Answer 9

1. **Vulvovaginitis
   - **pruritus vulvae
   - soreness
2. Thick, white / yellow, ***cheesy / curd-like discharge
3. ***Erythema of vulva, vagina
4. Skin fissure (sometimes)

Question 10

Predisposing factors of Candidiasis

Answer 10

1. **Pregnancy
   - asymptomatic colonisation more common (30-40%) –> colonisation **NOT associated with low birth weight / premature delivery
   - symptomatic candidiasis more prevalent
2. ***DM
3. ***Immunosuppression
4. ***OC pills
5. ***Broad spectrum antibiotics

ALL change defence mechanisms of vagina

Question 11

Diagnosis of Candidiasis

Answer 11

1. ***Clinical diagnosis
2. Vaginal swab from vaginal fornix
   - Microscopic exam (Wet mount: visualise spores / conidia, presence of blastospores / pseudohyphae can be detected in 30-50%)
   - Culture (more important if complicated: severe symptoms, pregnancy, recurrent, non-albicans candida infection, abnormal host)

Question 12

Treatment of Candidiasis

Answer 12

Asymptomatic: ***No need treatment

Symptomatic:
1. Genital hygiene
- keep genital area clean + dry
- use of vulval ***moisturisers as soap substitute + regular skin conditioner
- avoid tight fitting synthetic clothing
- avoid local irritants e.g. perfumed products

2. Antifungal (topical / oral / vaginal (preferred for pregnancy))
   - ***Clotrimazole (e.g. pessary 200mg for 3 nights)
   - Econazole
   - Miconazole
3. Maintenance therapy for recurrent candidiasis

Question 13

Group B Streptococcus (B型鏈球菌)

Answer 13

Streptococcus agalactiae
- Gram +ve cocci
- **GI tract primary reservoir
- Vaginal colonisation: 6-30% of **pregnant women
- ***NOT a STD!!!

Prevalence:
- +ve in 17-20% HK pregnant women

Question 14

Clinical features of GBS infection

Answer 14

Maternal risks
1. UTI
2. **PROM / PPROM (Premature / Preterm premature rupture of membranes)
3. **Preterm labour
4. ***Chorioamnionitis
5. Post-partum endometritis

Neonatal risks
Neonatal GBS colonisation:
- Vertical / Horizontal transmission
- 1 in 100-200 babies will show S/S of infection for GBS-colonised mothers
- ~1/1000 births in HK

1. Early onset neonatal infection (usually **<=3 days (SpC Neonatal teaching))
   - Vertical transmission
   - **Septicaemia, ***Pneumonia, Respiratory failure, Death (5-10%)
2. Late onset neonatal infection (up to **90 days (SpC Neonatal teaching))
   - Vertical / Horizontal transmission
   - **Meningitis, Pneumonia

Question 15

GBS screening

Answer 15

Criteria for screening:
1. Condition should be an important problem
2. Natural history of the condition should be adequately understood
3. A recognisable latent / early symptomatic state
4. An acceptable and effective treatment should be available
5. Facilities for diagnosis and treatment should be available
6. Cost effective
7. Associated risks should be acceptable to patients

GBS screening:
- Universal screening programme started since Jan 2012
- A **Low vaginal + **Rectal swab taken at **35-37 weeks
- GBS screening not required if **intrapartum antibiotic prophylaxis required / patients planned for ***C-section

Question 16

Intrapartum antibiotic prophylaxis

Answer 16

Indication:
1. **Positive screening (unless in elective C-section)
2. **Previous baby with “invasive” neonatal GBS disease
3. **GBS bacteriuria in current pregnancy
4. **Gestation (i.e. Labour) less than 37 weeks (except negative result)
5. **Maternal fever >38oC
6. **PROM for >18 hours
7. Screening result not available at leaking / onset of labour

Drug:
***IV Penicillin G (Benzylpenicillin)

If allergic:
- Cefazolin (if not at high risk of anaphylaxis)
- **Clindamycin, **Erythromycin, Vancomycin

• Helps to prevent early-onset GBS disease
• But is NOT 100%
• does NOT always prevent late-onset GBS infection
  –> babies may pick up GBS from people they come in contact with / via other means

Phoebe Lam:
Go into labour before GBS screening is done / before results available
–> Antibiotic prophylaxis during labour based on risk factors, including:
1. Ruptured membranes >18h
2. Preterm labour
3. Maternal fever >38oC

Complete prophylaxis:
- **>=4 hours before delivery
- reduces **Early-onset neonatal infection by 60-80%
- If Incomplete prophylaxis –> Secondary prevention (CBC, ***monitor for 48h)

Question 17

Breastfeeding in GBS carrier mother (SpC OG)

Answer 17

• GBS may colonise mother’s body
  —> Baby’s body may be colonised and shared the flora with mother in return
  —> A chance that breastmilk may be colonised, but not necessarily cause infection
  —> NO evidence to exclude breastfeeding for GBS mother

Question 18

Bacteria vaginosis (細菌性陰道炎)

Answer 18

Causative organism:
***Anaerobes
- Gardnerella vaginalis
- Prevotella spp.
- Mycoplasma hominis
- Mobiliuncus spp.

Pathophysiology:
- Lactobacilli replaced by Anaerobes –> pH ↑ to 7
- Can occur in sexually active / inactive women

Epidemiology:
- ***commonest cause of vaginal discharge in reproductive age women
- prevalence (UK): 5% in asymptomatic students, ~12% in pregnant women, 30% in women undergoing TOP (termination of pregnancy)
- more common in blacks, those with IUCD, smokers

Question 19

Clinical features of Bacteria vaginosis

Answer 19

1. ***Asymptomatic (50%)
2. ***Offensive, fishy-smelling vaginal discharge
3. Usually not associated with vulvovaginitis
4. ***Thin, white, homogenous discharge coating vaginal wall / vestibule

Question 20

Complications of Bacteria vaginosis

Answer 20

1. ***PID (although no evidence that treating asymptomatic women can prevent PID)
2. ***Late miscarriage
3. ***Preterm labour
4. PPROM
5. Post-TOP endometritis
6. Post-partum endometritis
7. Vaginal cuff cellulitis and abscess after vaginal hysterectomy

Question 21

Diagnosis of Bacteria vaginosis

Answer 21

1. ***High vaginal swab for culture
2. ***Amsel’s criteria (3 out of 4):
   - Thin, white, homogenous discharge
   - Clue cells (on microscopy)
   - pH of vaginal fluid >4.5
   - +ve Whiff test: release of fishy odour on adding alkali (10% KOH)

Question 22

Treatment of Bacteria vaginosis

Answer 22

1. Advice against vaginal douching, use of shower gels / antiseptic bath agents
2. Antibiotic (**symptomatic women, those undergoing surgery, pregnant women)
   - **Metronidazole
   –> oral: **400mg BD for 5-7 days / **2g single dose
   –> intravaginal gel
   or
   - Clindamycin cream

Metronidazole:
- enters breast milk and change its taste
–> avoid high dose in breast feeding / change to intravaginal form
–> if give single dose (2g), discontinue breast feeding for 12-24 hours to ↓ infant exposure

Role of screening uncertain in asymptomatic pregnant women

Question 23

Sexually transmitted diseases (STD)

Answer 23

Epidemiology:
- 13000 cases in social hygiene clinics annually

Top 5 diagnoses (descending frequency):
1. NGU / Non-specific genital infections
2. Genital wart
3. Gonorrhoea
4. Syphilis
5. Herpes genitalis

Question 24

Trichomoniasis (滴蟲陰道炎)

Answer 24

Causative organism: Trichomonas vaginalis
- flagellated ***protozoa
- sexually-transmitted

Risk factors:
- smokers
- Afro-Caribbean / African race
- lower educational level
- unsafe sex
- multiple sexual partners

Question 25

Clinical features of Trichomoniasis

Answer 25

1. Pruritus
2. Vaginitis, Dyspareunia (painful intercourse), Soreness
3. Foul smell, frothy, ***yellowish-green discharge
4. Post-coital bleeding in pregnant women
5. ***Strawberry cervix
6. Preterm birth + Low birth weight

Question 26

Diagnosis of Trichomoniasis

Answer 26

1. ***Clinical diagnosis
2. **High vaginal swab + **Wet mount + microscopy (sensitivity 51-65%)
   - specimens observed within 10 mins to observe motile parasites
3. ***Culture (sensitivity 75-96%)
   - take up to 7 days
4. Rapid Ag test (sensitivity 82-95%)
5. Nucleic acid amplification tests (sensitivity 90-100%)
6. PCR (sensitivity 95-100%)

QMH: 2+3

Question 27

Treatment of Trichomoniasis

Answer 27

1. ***Metronidazole
   - single dose 2g / 400mg BD for 5-7 days
   - enters breast milk and change its taste
   –> avoid high dose in breast feeding / change to intravaginal form
   –> if give single dose (2g), discontinue breast feeding for 12-24 hours to ↓ infant exposure
2. Screen for other STDs
3. Screen + Treat partner
4. Test of cure
   - only recommended if patient remains symptomatic after treatment / symptoms recur

Question 28

Chlamydia (衣原體感染)

Answer 28

Causative organism: Chlamydia trachomatis
- obligate intracellular parasite
- sexually transmitted

Risk factors:
- young age
- multiple sexual partners
- unsafe sex
- low socioeconomic class
- history of STD / PID

Epidemiology:
- varying prevalence (1-30%) (depending on study population)
- national screening programme for Chlamydia available in UK

Question 29

Clinical features of Chlamydia

Answer 29

Incubation period:
- 7-21 days

1. Mild symptoms / 75% ***Asymptomatic
2. ↑ Vaginal discharge
3. Dyspareunia
4. Intermenstrual bleeding
5. Abdominal pain
6. Dysuria
   (7. ***Peri-hepatic adhesions on laparoscopy)

Question 30

Complications of Chlamydia

Answer 30

1. PID
2. Chronic pelvic pain
3. ↑ risk of ectopic pregnancy in future
4. Subfertility
5. ***Fitz-Hugh-Curtis syndrome
6. ***Reiter’s syndrome (ACU) (inflammatory arthritis that develops in response to an infection in another part of body)
   - Urethritis
   - Conjunctivitis
   - Arthritis
7. ***Pregnancy-related
   - Preterm labour
   - PPROM
   - Low birth weight
   - Post-partum endometritis
   - Babies of affected mothers: Conjunctivitis (5-12 days), Pneumonitis (2-3 weeks)

Question 31

Diagnosis of Chlamydia

Answer 31

1. ***Endocervical swab / First void urine (mostly)
2. PCR + ligase chain reaction
3. ELISA
   - monoclonal chlamydia-specific Ab
   - less sensitive + false +ve (compared to culture)
4. Culture (***McCoy cell line)
   - expensive

QMH: Endocervical swab for Immunofluorescence + Culture

Question 32

Treatment of Chlamydia

Answer 32

1. Drug
   - Doxycycline (100mg BD for 7 days) / Tetracycline (Teratogenic)
   or
   - ***Azithromycin (1g single dose)
   or
   - Pregnancy: Azithromycin / Erythromycin / Amoxicillin
2. Screen for other STD
3. Contact tracing + Treatment of partner
4. Test of cure
   - not routinely recommended for uncomplicated genital chlamydia infection
   - recommended in pregnancy

Question 33

Gonorrhoea (淋病)

Answer 33

Causative organism: Neisseria gonorrhoeae
- Gram -ve diplococci
- kidney / bean-shaped
- found in genitourinary tract, rectum, **pharynx, **eyes
- sexually transmitted

Risk factors:
- same as other STDs

Question 34

Clinical features of Gonorrhoea

Answer 34

Incubation period: ~10 days

1. ***Asymptomatic (30-60%)
2. Dysuria, frequency
3. ↑ Vaginal discharge, yellowish green
4. Vaginal pruritus, burning
5. Post-coital bleeding
6. Vaginal erythema on speculum
7. ***Bartholin’s abscess: vulval swelling / pain

Question 35

Complications of Gonorrhoea

Answer 35

1. PID
2. ↑ risk of ectopic pregnancy
3. Subfertility
4. Chronic pelvic pain

**Systemic involvement:
1. **Arthritis
2. **Conjunctivitis
3. **Pharyngitis
4. Proctitis
5. Urethritis
6. Endocarditis
7. Meningitis
8. Disseminated gonococcal infection (rare)

Pregnancy-related:
1. Miscarriage
2. **Premature labour
3. PPROM
4. **Chorioamnionitis
5. SGA (Small for gestational age)
6. Stillbirth
7. Post-partum endometritis
8. Pelvic sepsis

Neonatal:
1. ***Ophthalmia neonatorium (first few days of life)

Question 36

Diagnosis of Gonorrhoea

Answer 36

1. Endocervical / Urethral / Anal / Pharyngeal swabs
2. Microscopy
   - Gram stain diplococci
3. Culture (***Thayer-Martin medium, Martin-Lewis medium)
4. PCR for DNA (expensive)

QMH: Endocervical swab taken for Culture

Question 37

Treatment of Gonorrhoea

Answer 37

1. Drug
   - Penicillin / Spectinomycin / Cephalosporin (e.g. **Ceftriaxone 500mg IM) + **Azithromycin 1g oral
   - Quinolone: ***high resistant rate, not given unless susceptible, CI in pregnancy
2. Screen for other STD
3. Contact tracing + Treatment of partner
4. ***Test of cure
   - important ∵ possible drug resistance
   - recommended in all cases

Question 38

Pelvic inflammatory disease (盆腔炎)

Answer 38

Pelvic infection:
- Infection of
1. Uterus
2. Fallopian tubes
3. Parametria
4. Overlying peritoneum
- NOT include lower genital tract: Vulva / Vagina

Route of infection:
- **Ascending from lower genital tract (most common)
- **From nearby organs (e.g. acute appendicitis)
- ***Haematogenous route

Causative organisms:
1. **Chlamydia trachomatis
2. **Neisseria gonorrhoeae
3. **Aerobic organisms
- Streptococci, Staphylococci, Coliforms, H. influenzae
4. **Anaerobic organisms
- Peptococci, Streptopeptococci, Clostridium spp., Bacteroides
5. Others
- Mycoplasma hominis, Ureaplasma urealyticum
- TB
- Actinomyces

Risk factors:
- Risky sexual behaviour
- Post-abortal
- Puerperium
- Following surgery
- IUCD insertion (first 2-4 weeks)

Question 39

***Clinical features of PID

Answer 39

1. ***Abdominal pain
2. ***Fever
3. ***Vaginal discharge / bleeding
4. Urinary symptoms
5. GI symptoms

Important to ask for risk factors + previous history of PID

Physical signs for PID:
1. Fever
2. BP, pulse (hypotension, tachycardia indicate sepsis)
3. Abdomen
- signs of **peritonitis (indicate severe disease)
4. Vagina
- hot, discharge
5. **Cervical excitation tenderness
6. **Uterine and Adnexal tenderness
7. **Adnexal mass
- tubo-ovarian complex / abscess

Question 40

Diagnosis of PID

Answer 40

**Presumptive diagnosis
- **Sexually active women experiencing pelvic / lower abdominal pain
- **Absence of other causes
- With **cervical excitation / uterine / adnexal tenderness
–> early treatment is important to prevent future sequelae

***DDx:
- Ectopic pregnancy
- Ovarian cyst complication
- UTI
- Acute appendicitis

Question 41

Investigations of PID

Answer 41

1. CBP
   - Leukocytosis
   - ESR, CRP
2. ***Endocervical swab
   - Gonococcus
   - Chlamydia
   - Culture
3. ***High vaginal swab
   - Trichomonas (as part of STD screening)
   - Culture
4. VDRL (to exclude Syphilis)
5. HIV-Ab (to exclude HIV)
6. ***Pregnancy test (to exclude ectopic pregnancy)
7. ***USG pelvis (to exclude ovarian cyst complication)
8. ***MSU (to exclude UTI)
9. Cervical smear (opportunistic screening if due for smear)

Question 42

Treatment of PID

Answer 42

1. Monitor vitals
2. Fluid replacement
3. ***Broad spectrum antibiotic (∵ caused by multiple organisms)
   - Neisseria gonorrhoeae
   - Chlamydia trachomatis
   - Anaerobes
   - Gram -ve facultative bacteria
   - Streptococci

Out-patient treatment:
1. Recommended
- **Ceftriaxone 1g IM single dose + **Doxycycline 100mg oral BD + ***Metronidazole 400mg BD oral for 14 days

2. Alternative (e.g. penicillin allergy)
   - Ofloxacin 400mg BD oral + Metronidazole 400mg BD oral for 14 days (disabling + potentially permanent SE: tendons, muscles, joints, nervous system)
   - Moxifloxacin 400mg OD 14 days oral (for Mycoplasma genitalium)
   - Ceftriaxone 1g IM + Azithromycin 1g oral per week for 2 weeks

In-patient treatment:
Indications:
- Surgical emergency cannot be excluded
- Clinically severe disease
- **Tuboovarian abscess
- **PID in pregnancy
- Lack of response to oral therapy
- Intolerance to oral therapy

1. **IV Antibiotic should be continued until 24 hours after clinical improvement –> followed by **oral therapy
   Recommended:
   - **Ceftriaxone 2g IV daily + **Doxycycline 100mg BD –> Doxycycline 100mg BD + Metronidazole 400mg BD for total of 14 days
   - Cefoxitin 1-2g QDS IV
   - Augmentin + Doxycycline IV

Alternative:
- Clindamycin 900mg TDS IV + Gentamicin IV (2 mg/kg loading dose –> 1.5 mg/kg TDS / single daily dose of 7 mg/kg –> Clindamycin 450mg QDS oral / Doxycycline 100mg BD + Metronidazole 400mg BD oral to complete 14 days

2. Important to review progress
3. Role of surgical intervention: Tubo-ovarian abscess –> image guided drainage / laparoscopy / laparotomy

Question 43

Management of PID in patients with IUD

Answer 43

• Whether to remove IUD is controversial
• Decision to remove IUD balanced against Risk of pregnancy in those had unprotected intercourse in previous 7 days
• If no clinical improvement within 48-72 hours of treatment –> should consider removing IUD

Question 44

Complications of PID

Answer 44

Early:
1. **Tubo-ovarian abscess
2. **Septic shock

Late:
1. **Recurrent PID (25%)
2. **Chronic pelvic pain
- Dysmenorrhoea, Dyspareunia
- 15-20%
3. **Fitz-Hugh-Curtis syndrome
4. **Ectopic pregnancy
5. ***Subfertility (∵Tubal obstruction)
- ~20%
- 1 episode of PID: 13%
- 2 episodes: 36%
- 3 episodes: 75%

Question 45

Prevention of PID

Answer 45

1. Education
   - avoid risky sexual behaviour
2. ***Barrier methods for contraception
3. Prompt diagnosis + treatment
4. ***Contact tracing + treatment

Question 46

Summary: Approach to STI

Answer 46

1. Sensitive
2. ***Screen for other STIs (HIV, VDRL)
3. Treat appropriately + quickly
4. ***Partner(s) referral + treatment
5. Special consideration during pregnancy
   - early treatment to avoid effect on baby
   - use appropriate + safe antibiotics
6. Safer sex education
7. Cervical smear (if opportunistic)
8. Counselling on possible sequelae

Question 47

General Advice for all vulval conditions (SpC Revision)

Answer 47

1. Avoid contact with soap, shampoo and bubble bath
2. Simple emollients can be used as a soap substitute and general moisturiser
3. Avoid tight fitting garments which may irritate the area
4. Avoid use of spermicidally lubricated condoms