Pelvic inflammatory disease
Definition
• Collection of upper genital tract infections in women
• Comprises salpingitis, endometritis, myometritis, parametritis,
oophoritis, tubo-ovarian abscess, peritonitis and perihepatitis
• Most common serious infection in women aged 16-25
• Most common gynaecological cause of ED presentations
• Often present with non-specific complaints
Organisms
• C. trachomatis and N. gonorrhoea instrumental in initial infectious process with
polymicrobial infections arising as inflammation increases and abscesses form
• Mixed infection in 30-40% of cases
• STI: Chlamydia, Gonorrhoea, Trichomoniasis, HSV
• Other:
• Endogenous mycoplasma: M. genitalium, Ureaplasma urealyticum, M. hominis
• Anaerobes: Bacteroides, Peptostreptococcus
• Aerobes: Gardnerella vaginalis, H. influenzae, S. agalactiae, E. coli
• 10-20% of untreated gonorrhoea or chlamydia will progress to PID
• Bilateral tubal ligation does NOT provide protection but patients have less
severe or delayed disease in most cases
Risk factors
• Multiple sexual partners
• Hx of STI or PID
• Hx of sexual abuse
• Frequent vaginal douching
• IUD within previous month
• Overall 10/1000 insertions, with greatest risk in first 20 days
• Adolescence, young adults
Complications
• Tubo-ovarian abscess in 1/3 of women hospitalised for PID
• Rate of ectopic pregnancy 12-15% higher if previous PID
• Tubal factor infertility rises with each episode
• 12-50% incidence
• 50% of women with tubal factor infertility have no hx of PID but have
scarring consistent with this (silent PID)
• Chronic pelvic pain 18%
• Menstrual disturbances
• Dyspareunia
History
• Lower abdominal pain (>90% of cases)
• Abnormal vaginal discharge (75% of cases)
• Vaginal and postcoital bleeding (30% of cases)
• Irritative voiding symptoms
• Fever, malaise, nausea, vomiting
• Need full obs/gyn history in all cases
Examination
• Lower abdominal tenderness, cervical motion tenderness, adnexal or uterine
tenderness
• May have associated peritonitis
• Adnexal tenderness is the most sensitive finding (95%)
• Mucopurulent cervicitis is common and absence should raise suspicion of an
alternative diagnosis
• Fever, adnexal tenderness and elevated ESR are all independent predictors of
endometritis
• RUQ tenderness, esp. with jaundice, may indicate Fitz-Hugh-Curtis syndrome
• Seen in 4% of mild-moderate PID
• May not have any PID symptoms/signs
• Normal LFT
• USS useless and needs CT or laparoscopy for diagnosis
Differential
• Adnexal torsion
• Ectopic pregnancy
• Cervicitis
• Endometriosis
• Ovarian cyst +- rupture
• Spontaneous abortion
• Septic abortion
• Cholecystitis
• Appendicitis
• Diverticulitis
• Pyelonephritis
• Renal colic
Investigations
• CT with contrast if appendicitis cannot be ruled out
• Pregnancy test
• Endocervical and high vaginal swabs
• Raised WCC, ESR or CRP support diagnosis
• Urinalysis to exclude UTI
• Blood cultures are NOT helpful unless septic
• Urine PCR for STI
• 95% sensitive for C. trachomatis (vs. 80% for swabs)
• 92% sensitivity for Gonorrhoea (vs. 97% for swabs)
• Endocervical swab for STI
• Adds diagnostic utility only if purulent discharge for Gonorrhoea
Transvaginal USS
• Findings
• May demonstrate thickened (>5mm), fluid-filled fallopian tubes
• Free pelvic fluid
• Not specific enough for definitive diagnosis
• Tubo-ovarian abscess may appear as a complex adnexal masses with
multiple internal echoes
• May also help rule out ovarian torsion, haemorrhagic ovarian cyst,
appendicitis and endometriosis
Abdominopelvic CT/MRI
• May show
• Obscuration of pelvic fascial planes
• Cervicitis
• Oophoritis
• Salpingitis
• Thickening of uterosacral ligaments
• Simple or complex pelvic fluid or abscess collections
• Can help rule out adnexal torsion if USS has shown normal ovarian
anatomy
Laparoscopy
• Gold standard for diagnosis
• Most sensitive and specific than clinical criteria
• Can obtain material for definitive culture without vaginal contamination
• Fails to identify PID in 20% still as can only see surface of organs and as
such may not appreciate full extent of disease/miss diagnosis
Diagnosis (CDC)
• Group 1: Minimum criteria
• Uterine or adnexal tenderness
• Cervical motion tenderness
• Group 2: Additional criteria to improve diagnostic accuracy
• Oral temp >38.3
• Abnormal cervical mucopurulent secretions
• Elevated ESR or CRP
• Lab evidence of N. gonorrhoea or C. trachomatis
• Group 3: Specific criteria for PID based on procedures that may be suitable for
patients
• Laparoscopic confirmation
• TVUSS (or MRI) showing thickened, fluid-filled tubes with/without pelvic free fluid or tuboovarian
abscess
• Endometrial biopsy showing endometritis
Treatment
• Recommended to maintain low threshold for aggressive therapy as crucial to treat
early in maintaining fertility, preventing transmission and improving symptoms
• Long-term outcomes are improved by early empirical treatment
• Large trial showed no difference between oral and parenteral treatment regimes
• CDC guidelines
• Empiric treatment recommended for women at risk who exhibit lower abdominal pain,
adnexal tenderness and cervical motion tenderness (as per groups above)
• Antibiotics (See next) + Analgesia, antipyretics, antiemetics
• Remain abstinent or adhere strictly to condom use, until symptoms have abated and
entire antibiotic regime complete
• Contact tracing for positive results
Treatment (Dunn)
Sexually acquired
• Mild/moderate – Azithromycin 1g PO stat + Metronidazole 400mg BD for 14 days + Ceftriaxone 250mg IM/IV stat + repeat Azithromycin in one week or give doxycycline course 100mg BD for 14 days (poor compliance)
• Severe – Ceftriaxone 2g IV daily + Metronidazole 500mg IV BD + Azithromycin 500mg IV daily with ultimate 2 week course
Non-sexually acquired
• Mild/moderate – Augmentin 875/125 BD + Doxycycline 100mg BD for 14 days
• Severe – Amp/Gent/Metronidazole
Treatment
• Mild-moderate sexually acquired PID – Azithromycin 1g PO stat then repeat in 7 days, Metronidazole 400mg PO q12h for 14 days, Ceftriaxone 500mg IM or IV as single dose if gonorrhoea suspected
• Mild-moderate non-sexually acquired PID – Augmentin q12h for 14 days, Azithromycin 1g PO stat and repeat in 7 days
• Severe sexually acquired PID – Ceftriaxone 2g daily IV + Azithromycin 500mg IV daily + Metronidazole 500mg IV q12h
• Admit and treat as severe if HIV + irrespective of CD4+ count
• Studies have shown poor compliance with doxycycline therapy (alternative regimes to above), 20-25% of patients never fill their
script
• Can change to oral therapy after 24 hours if improvement and total course of 14 days
• Re-evaluate at 72 hours for clinical improvement if discharged home
• Single dose azithromycin effective for lower tract STI but NOT upper tract
Tubo-ovarian abscess
• Disproportionate unilateral adnexal tenderness or adnexal mass/
fullness may indicate tubo-ovarian abscess
• 60-80% resolve with antibiotics alone
• If this fails, laparoscopy may be useful for identifying potentially
drainable abscess or demonstrate alternative pathology
Who gets admitted?
• Parenteral regimes if severe and HITH not available
• Severe symptoms
• Low likelihood of adherence to outpatient regime
• High likelihood of major anaerobic infection (IUD, suspected abscess or recent
instrumentation)
• Uncertainty of diagnosis
• Coexisting illness
• Immunosuppressed
• Pregnant
• Major fertility issues
Contact tracing
• All sexual partners of the last 60 days require treatment empirically for
both Chlamydia and Gonorrhoea
Last Updated on September 27, 2021 by Andrew Crofton