JC105 (O&G) - Obstetric and gynaecological infections Flashcards
List natural immune defenses in the female genital tract
Apposition of labia & vaginal walls
Stratified squamous epithelium in lower genital tract (natural resistance to infection)
Vaginal microbiome (especially lactobacilli)
Vaginal acidity (pH 3.5-4.5)
Factors that adversely affect immune defense in the female genital tract
Menstrual cycle – secretions (alkaline) around menses
Pregnancy & puerperium:
high pH
Higher estrogen levels and higher glycogen content in vaginal secretions
Trauma at delivery infection in lower genital tract
Lochia (alkaline) – heavy flow of blood and mucus that starts after delivery
Diabetes
Antibiotics
Non-infectious causes of vaginal discharge
Physiological (hormones)
Cervical ectropian
Foreign bodies (IUCD, ring pessary for prolapse)
Vulval dermatitis
Benign and malignant tumours (cervical cancer)
Infectious causes of vaginal discharge
Non-sexually transmitted
Bacterial vaginosis
Candidiasis
Group B Streptococcus
Sexually transmitted
Chlamydia trachomatis
Neisseria gonorrhea
Trichomonas vaginalis
Outline history taking questions for vaginal discharge
History: Differentiate between physiological vs. pathological discharge
Timing of discharge
Smell, color, character
Associated symptoms, e.g. abdominal pain, fever, pruritus
Contraception (IUCD - non-infectious cause of vaginal discharge)
Past health (diabetes)
Cervical smear (up to date? Normal?)
Previous obstetrics history
Top 5 STDs in Hong Kong
- Non-gonococcal urethritis/ nonspecific genital infection
- Genital warts/ condyloma acuminatum - HPV
- Gonorhoea
- Syphilis
- Herpes genitalis
Follow-up tests, referrals and plan of action after STI diagnosis
Present illness:
Screen for other STIs (HIV, VDRL)
Treatment (appropriate and prompt)
Sex partner:
Partner(s) referral (to social health clinics) & treatment
Safer sex education (e.g. barrier method)
Gynaecological:
Special consideration during pregnancy (treat to prevent preterm labor; use safe antibiotics for babies)
Cervical smear (opportunistic screening)
Counselling on possible sequaelae
Pelvic inflammatory disease
- Structures infected
- Routes of infection
- Causative organisms
pelvic infection:
Infection of the uterus, fallopian tubes, adjacent parametria & overlying peritoneum
Does not include lower genital tract (vulval/ vaginal infection)
Route of infection:
- Ascending – from the lower genital tract (most common)
- From nearby organs, e.g. acute appendicitis
- Haematological route
Causative organisms:
Sexually transmitted: Chlamydia trachomatis, Neisseria gonorrhoeae
Aerobic organisms: staphylococci, streptococci, coliforms, Haemophilus influenzae
Anaerobic organisms: Clostridium sp., bacteroides, peptococci, streptopeptococci
Others (less common): Mycobacterium tuberculosis, Actinomyces…etc
Pelvic inflammatory disease
- Risk factors
Risk factors: Existing lower genital tract infection/ hematogenous infection Risky sexual behaviour Post-abortal Puerperium Following surgery IUCD insertion (first 2-4 weeks) Previous history of PID
Pelvic inflammatory disease
- S/S
Symptoms: Abdominal pain Fever Vaginal discharge/ abnormal uterine bleeding Urinary symptoms GI symptoms
Signs:
Fever, BP, pulse (hypotension and tachycardia can indicate severe sepsis)
Abdomen: signs of peritonitis (severe disease, or other DDx)
Vagina: hot, discharge
Cervical excitation tenderness
Uterine & adnexal tenderness
Adnexal mass (tubo-ovarian complex/abscess)
Describe the patient presentation that needs presumptive Dx of PID and early treatment
Sexually active women experiencing pelvic/ lower abdominal pain
In the absence of other cause
With cervical motion/ uterine/ adnexal tenderness
Ddx of pelvic inflammatory disease
Ectopic pregnancy
Ovarian cyst complication
Urinary tract infection
Acute appendicitis
First-line investigations for PID
Blood: CBP – leukocytosis, (+/- inflammatory markers: ESR, CRP)
Microbiology:
Endocervical swabs: Chlamydia (IF + culture), gonococcus (culture)
High vaginal swabs: trichomonas (microscopy, culture)
Blood: VDRL (syphilis), HIV-Ab
MSU: UTI
Cervical pap smear
Additional
Pregnancy test (exclude ectopic pregnancy)
USG or MRI pelvis: ovarian cyst complications
Outpatient treatment options for Pelvic inflammatory disease
Recommended:
1. IM ceftriaxone + oral doxycycline + oral metronidazole
Alternative:
2. Oral Ofloxacin + oral metronidazole (high ride effects)
3. Oral moxifloxacin (best against M. genitalium infection)
4. Intramuscular ceftriaxone + oral azithromycin (last-line)
Indications for adding metronidazole:
Evidence/ suspicion of vaginitis (Trichomonas); or
The patient underwent gynecologic instrumentation in the
preceding 2-3 weeks
Inpatient treatment option for PID
Continue intravenous antibiotic until 24 hours after clinical improvement follow by oral therapy
First-line:
IV Ceftriaxone + Oral antibiotics
Follow by: Oral doxycycline or oral metronidazole
Alternatives:
- IV cefoxitin
- IV augmentin + IV doxycycline
- IV clindamycin/ IV Gentamicin + oral clindamycin or oral metronidazole
Indications for inpatient treatment of PID
Cannot exclude surgical emergency Clinically severe disease Tubo-ovarian abscess complication (adnexal mass) PID in pregnancy Lack of response to oral therapy Intolerance to oral therapy
Last-resort treatment options for PID refractory to medication
Surgical intervention for tubo-ovarian abscess not responding to antibiotrics (image-guided drainage/ laparoscopy/ laparotomy)
Remove IUD (controversial): Consider if no clinical improvement occurs within 48-72 hours of treatment Balance against the risk of pregnancy in those who have had otherwise unprotected intercourse in the preceding 7 days
Treat male partners of women with PID empirically with doxycycline,
Complications of PID
Early:
Tubo-ovarian abscess
Septic shock
Late: Recurrent PID Chronic pelvic pain (15-20%): dysmenorrhoea, dyspareunia Fitz-Hugh-Curtis syndrome Ectopic pregnancy Subfertility (tubal obstruction)
Prevention methods of recurrent PID
Education (avoid risky sexual behavior)
Contraception (barrier methods, e.g. condom)
Prompt diagnosis and treatment
Contact tracing and treatment
List 3 Non-sexually transmitted disease that cause vaginal discharge
Bacterial vaginosis
Vulvovaginal candidiasis/ Candida vulvovaginitis
Group B Streptococcus(GBS) infection
Bacterial vaginosis
- Prevalence
- Causative pathogens
- Risk factors
- Type of discharge and presentation
commonest cause of vaginal discharge in reproductive aged women
Pathogens: Mainly anaerobes (Gardnerella vaginalis, Prevotella sp., Mycoplasma hominis, Mobiliuncus sp.)
Risk factors: Black IUCD Smokers Antibiotics Sex
Types of discharge:
- offensive, fishy-smelling
- Thin, white, homogeneous discharge coating vaginal wall/ vestibule
- Not usually associated with vulvo-vaginitis
Bacterial vaginosis
Complications
Infections:
PID
Post-TOP endometritis
Pregnancy-related: Late miscarriage Preterm labour PPROM (Preterm premature rupture of the membranes, pregnancy complication) Postpartum endometritis
Iatrogenic:
Vaginal cuff cellulitis and abscess after vaginal hysterectomy
Bacterial vaginosis
Diagnostic tests
Amsel’s criteria (3 out of 4): indicate high vaginal swab
- Thin, white homogeneous discharge
- Clue cells on microscopy
- pH of vaginal fluid >4.5
- Release of fishy odour on adding alkali (10% KOH) (‘whiff’ test positive)
Bacterial vaginosis
- management options
General:
Advice against vaginal douching/ use of shower gels/ antiseptic bath agents
Antibiotics: Indications: Symptomatic women Those undergoing surgery Pregnant women Options: - Oral metronidazole (non-breastfeeding) - Intravaginal gel (breastfeeding) - CLindamycin cream
Vulvovaginal candidiasis/ Candida vulvovaginitis
Causative pathogens
Risk factors
Vaginal discharge and presentation
Pathogen: Candida albicans
Risk factors: change defense mechanism of vagina Pregnancy Diabetes, immunosuppression Oral contraceptive pills Broad spectrum antibiotics
Presentation:
- thick, white/yellow, cheesy
- Vulvovaginitis: pruritus vulvae, soreness
- Erythema of vulva, vagina
- May cause skin fissure
Vulvovaginal candidiasis/ Candida vulvovaginitis
Diagnostic tests
Vaginal swab from vaginal fornix (vaginal discharge/ scraping from vulvar lesions) for:
- Microscopic examination: mix with saline and wet mount
- Slings of pseudohyphae of Candida albicans surrounded by round vaginal epithelial cells
- Blastospores, conidia - ± culture for complicated cases: severe symptoms, pregnancy, abnormal host,
non-albicans, recurrent
Vulvovaginal candidiasis/ Candida vulvovaginitis
Treatment options
asymptomatic: no need
Symptomatic
1. Genital hygiene:
Keep genital area clean and dry
Avoid tight fitting synthetic clothing
Avoid local irritants in vulvovaginal area, e.g. perfumed products
Use vulval moisturisers as soap substitute, and regular skin conditioner
- Antifungal agents, e.g. clotrimazole, econazole, miconazole:
Topical, oral (e.g. clotrimazole pessary 200 mg for 3 nights)
Vaginal route for pregnant women
Maintenance therapy for recurrent candidiasis (rare)
Group B Streptococcus(GBS) infection of female genital tract
- Causative pathogen
- Vaginal discharge and presentation
- Complications
Causative pathogen: Streptococcus agalactiae (primary reservoir in GIT)
Presentation: yellow or green discharge, vaginal burning and/or irritation
Complications:
Maternal risks:
UTI
PROM / PPROM (premature rupture of membranes = PROM before 37 weeks)
Preterm labour
Chorioamnionitis (associated with prolonged labor)
Post-partum endometritis
Neonatal infection:
- Early vertical infection: Septicaemia, pneumonia, respiratory failure, death
- Late vertical/ horizontal infection: Meningitis, pneumonia
GBS infection of female genital tract
- DIagnostic tests in pregnant women
- Indication for testing
Universal Group B Streptococcus screening:
- low vaginal and rectal swab at 35-37 weeks
Not required if:
Required intrapartum antibiotic prophylaxis; or
Planned for caesarean section
GBS infection of female genital tract
Treatment options
Effectiveness
Intrapartum antibiotic prophylaxis (during labor):
- Penicillin G/ benzyl penicillin
Alternatives to penicillin:
- cefazolin/ clindamycin/ erythromycin/ vancomycin
Effectiveness:
- Prevents early-onset GBS infection (not 100%)
- Cannot prevent late-onset GBS infection/ horizontal infections
Chlamydial infections in women
- Causative pathogen
- Risk factors
- Incubation period
- Presentation
Pathogen: Chlamydia trachomatis (obligate intracellular gram negative bacterium)
Risk factors:
Young age
Multisexual partners, unsafe sex, low socioeconomic class
History of STD/ PID
Incubation: 7-21 days
Presentation: Most asymptomatic
- Dysuria
- Abnormal vaginal Mucopurulent discharge
- Intermenstrual or postcoital bleeding
- Deep dyspareunia
- Lower abdominal pain
- Cervicitis +/- contact bleeding
(Men: Urethritis, Dysuria, Urethral discharge, Epididymo-orchitis)
Chlamydial infections
Complications
PID
Chronic pelvic pain
Pregnancy: Increased risk of ectopic pregnancy Subfertility Preterm labour PPROM Low birth weight Post-partum endometritis
Syndromes:
Reiter’s Syndrome – urethritis, conjunctivitis and arthritis
Fitz-Hugh-Curtis Syndrome: perihepatitis/ perihepatic adhesions seen in laparotomy
Complication in babies:
Conjunctivitis (5-12 days)
Pneumonitis (2-3 weeks)
Chlamydial infections
Diagnostic tests
Endocervical swab and/or first void urine:
Immunofluorescence
Culture (McCoy cell line)
PCR, ligase chain reaction
ELISA: Monoclonal Chlamydia-specific antibodies
Chlamydial infections
Treatment options
Recommended:
- Doxycycline (100 mg bd for 7 days)
Alternative for Allergic/ intolerant/ pregnancy:
- azithromycin (1g oral single dose, then 500mg daily for 2 days)
- erythromycin
- amoxicillin
- Screen for other STD
- Contact tracing and treatment
- Test of cure - Recommended in pregnancy (implication in newborn)
Gonorrhea
- Causative organism
- Risk factors
- Incubation period
- Presentation
Neisseria gonorrhoeae:
Gram-negative diplococci
Risk factors:
Multisexual partners, unsafe sex, low socioeconomic class
History of STD/ PID
Incubation period: 10 days
Presentation: yellow- green vaginal discharge Dysuria, frequency Vaginal pruritus, burning Post-coital bleeding Speculum exam: Vaginal erythema Vulval swelling/ pain – Bartholin’s abscess
Gonorrhea
Complications in women
PID
Chronic pelvic pain
Increased risk of ectopic pregnancy
Subfertility
Systemic involvement: Arthritis, conjunctivitis, urethritis Pharyngitis Proctitis Endocarditis Meningitis Disseminated gonococcal infection (rare)
Pregnancy: Miscarriage Premature labour PPROM Chorioamnionitis SGA (small for gestational age) Stillbirth Post-partum endometritis and pelvic sepsis
Baby: Ophthalmia neonatorum (first few days of life)
Gonorrhea
Diagnostic test
Endocervical, urethral, anal, pharyngeal swabs:
Microscopy: Gram-negative diplococci
Culture (Thayer-Martin medium, Martin-Lewis medium)
PCR for DNA
Gonorrhea
Treatment options
- Recommended within 14 days of exposure:
IM ceftriaxone
Alternatives:
- Ciprofloxacin if C/ST shows sensitive
- IM ceftriaxone + azithromycin
- IM spectinomycin + azithromycin
- do not use quinolone due to pregnancy S/E and high resistance**
- Screen for other STD
- Contact tracing
- Test of cure for all cases
Trichomoniasis
- Causative pathogen
- Risk factors
- Presentation
- Complications
Pathogen: Trichomonas vaginalis (flagellated protozoal parasite)
Risk factors: Smokers Afro-Caribbean/ African race Lower educational level, unsafe sex, multiple sexual partners
Presentation:
- Foul smell, frothy, yellowish-green
- Vaginitis: usually present with pruritus, soreness, dyspareunia
- Post-coital bleeding (in pregnant women)
Speculum: Strawberry cervix
Pregnancy Cx:
Preterm birth
Low birth weight
Trichomoniasis
Diagnostic tests
High vaginal swab
- Wet mount for microscopy: motile parasites
- Culture (7 days)
- Rapid antigen test (immunofluorescence, enzyme immunoassay)
- Nucleic acid amplification tests (NAAT): detect rRNA
- PCR
Trichomoniasis
Treatment options
For symptomatic women:
1. Metronidazole (oral) for 5-7 days or single high dose
(Avoid high dose if pregnant/ breast feeding)
2. Screen for other STDs
3. Screen and treat partner
4. Test of cure if symptomatic despite Tx/ recurrence
