Summary
Pelvic inflammatory disease (PID) is caused by a bacterial infection that spreads beyond the cervix to infect the upper female reproductive tract, including the uterus, fallopian tubes, ovaries, and surrounding tissue. The most common pathogens that cause PID are Chlamydia and Gonococci. Symptoms may vary considerably; while some women are asymptomatic, others may complain of mild pressure pain and discharge or present with signs of systemic inflammation, such as fever and severe abdominal pain. Diagnosis is based on clinical findings and may be supported by ultrasound, PCR, and/or cultures of cervical and urethral discharges. Calculated parenteral antibiotic therapy is indicated in women with suspected PID. Most common complications include infertility, ectopic pregnancy, and chronic pelvic pain.
Epidemiology
- Lifetime prevalence: ∼ 4.5% in women of reproductive age (18–44 years) [1]
- > 1 million women experience an episode of PID/year. [2]
- PID is one of the most common causes of infertility. [1]
Epidemiological data refers to the US, unless otherwise specified.
Etiology
-
Pathogens [3][4]
- Most common: Chlamydia trachomatis, Neisseria gonorrhoeae
- Less common (consider coinfections): E. coli, Ureaplasma, Mycoplasma, and other anaerobes
-
Risk factors [4]
- Multiple sexual partners, unprotected sex
- History of prior STIs and/or adnexitis
- Intrauterine devices [3]
- Risk is lower during pregnancy; PID development during pregnancy increases the risk of maternal morbidity and preterm births. [5]
- Vaginal dysbiosis [6]
- Pathophysiology: Infection from the lower genital tract (e.g., vagina, cervix) ascends to infect the upper reproductive tract (endometrium, fallopian tubes, ovaries) and/or peritoneal cavity.
-
Possible sites of infection
- Endometrium: endometritis (see also “Postpartum endometritis”)
- Fallopian tubes: salpingitis
- Ovaries: oophoritis
- Uterine adnexa: adnexitis
- Surrounding pelvic structures (parametritis) or, in some cases, the peritoneum (peritonitis)
Clinical features
- Lower abdominal pain (generally bilateral), which may progress to acute abdomen [7]
- Nausea, vomiting
- Fever
- Dysuria, urinary urgency
- Menorrhagia, metrorrhagia
- Dyspareunia
- Abnormal vaginal discharge (yellow/green color)
Diagnostics
Diagnosis is primarily based on clinical findings. Further diagnostic tests help confirm the diagnosis, especially in ambiguous cases.
-
Important diagnostic criteria [8]
- Patient history: most often a sexually active young woman
- Lower abdominal pain
- Vaginal examination
- Cervical motion tenderness: severe cervical pain elicited by pelvic examination
- Uterine and/or adnexal tenderness
- Purulent, bloody cervical and/or vaginal discharge
- Blood tests: : elevated ESR, leukocytosis
- Pregnancy test: to rule out an (ectopic) pregnancy
-
Cervical and urethral swab
- Gonococcal and chlamydial DNA (PCR) and cultures (see “Gonorrhea” and “Chlamydia infections”)
- Giemsa stain of discharge can show cytoplasmic inclusions in C. trachomatis infections, but not in N. gonorrhoeae infection.
-
Imaging
- Ultrasound: free fluid, abscesses, pyosalpinx/hydrosalpinx
- Exploratory laparoscopy [9]
- Endometrial biopsy: to confirm the presence of endometritis [1]
-
Culdocentesis: aspiration of intraperitoneal fluid from the pouch of Douglas [10]
- Reveals nature of the fluid (e.g., serous, purulent, bloody)
- Culdocentesis is no longer a routine procedure and it has been largely replaced by ultrasound.
PID may manifest with symptoms of appendicitis due to periappendicitis or perihepatitis. Symptoms may also mimic ectopic pregnancy.
PID should be suspected in young, sexually active women who present with lower abdominal pain and adnexal/cervical motion tenderness.
Differential diagnoses
Differential diagnosis of lower abdominal pain in women of reproductive age | |||
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Disorder | Clinical features | Diagnostic clues | Therapy |
Ectopic pregnancy |
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PID |
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Appendicitis |
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Kidney stones |
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Ovarian cyst rupture |
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|
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Ovarian torsion |
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|
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Pelvic cellulitis [11] |
|
|
Cervicitis [12]
- Definition: inflammation of the uterine cervix
-
Etiology
- Infectious (most common): C. trachomatis, N. gonorrhea, HSV-2 , T. vaginalis
- Noninfectious
- Localized trauma (e.g., cervical caps, diaphragms, tampons)
- Chemical irritation (e.g., contraceptive creams, latex exposure)
- Malignancy
-
Risk factors
- Young age
- Multiple sexual partners
- New sexual partner within the last 6 months
- Unprotected intercourse
-
Clinical features
- Often asymptomatic
- Usually no fever
- Vaginal discharge: may be purulent, blood-tinged, and/or malodorous
- Dyspareunia
- Postcoital or intermenstrual bleeding
- Lower abdominal or pelvic pain
- Symptoms of the underlying condition (e.g., genital lesions in HSV infections)
-
Physical examination
- Abdominal palpation: possible tenderness/discomfort (if concomitant PID is present) [13]
- Bimanual examination: motion tenderness of the cervix
- Pelvic examination: erythematous, edematous, friable cervix ; possibly visible discharge
-
Diagnostics
-
Diagnosis mainly clinical [3]
- Mucopurulent discharge
- Friable cervix on pelvic examination
- Further tests for identification of a pathogen
- Assess vaginal secretions for appearance, pH , leukocyte count, and visible pathogens (e.g., protozoa in T. vaginalis infections)
- Swab samples for bacterial culture
- NAAT for N. gonorrhea and C. trachomatis
-
Diagnosis mainly clinical [3]
-
Treatment
- Antibiotics; are tailored to the causative agent (see “Treatment” section below).
- Evaluate sex partner(s) of patients with infectious cervicitis.
- Follow-up to evaluate treatment success.
- Complications: PID
The differential diagnoses listed here are not exhaustive.
Treatment
Empirical antibiotic therapy (also consider coinfections) [1][3]
-
Outpatient regimen
- One single dose of IM ceftriaxone and oral therapy with doxycycline
- Signs of vaginitis or recent gynecological instrumentation: Add oral metronidazole.
-
Inpatient regimen (parenteral antibiotics)
- Indications
- No response to or inability to take outpatient oral regimen
- Non-compliance concerns (e.g., teenagers)
- Severe illness with nausea, vomiting, and/or high fever
- Tuboovarian abscess
- Pregnancy
- Possible combinations (should be administered for 14 days)
- Cefoxitin or cefotetan plus doxycycline
- Clindamycin plus gentamicin
- In the case of tuboovarian abscess: Add oral metronidazole or clindamycin (to enhance anaerobic coverage).
- Switch to oral therapy with doxycycline after clinical improvement.
- Indications
It is better to overtreat rather than delay treatment if PID is suspected.
Complications
-
Short-term complications
- Pelvic peritonitis
-
Fitz-Hugh-Curtis syndrome (perihepatitis)
- Inflammation of the liver capsule
- Characterized by violin-string-like adhesions extending from the peritoneum to the liver
- Tubo-ovarian abscess
-
Long-term complications
- Infertility: caused by adnexitis, adhesions of the fallopian tubes and ovaries, and tubal scarring, which result in impaired ciliary function and tubal occlusion
- Ectopic pregnancy
- Chronic pelvic pain
- Hydrosalpinx/pyosalpinx: accumulation of fluid/pus in the fallopian tubes due to chronic inflammation and consequent stenosis
- Chronic salpingitis
We list the most important complications. The selection is not exhaustive.