Definition –
A clinical spectrum of infection that may involve the cervix, endometrium, fallopian tubes, ovaries, uterus, broad ligaments, intraperitoneal cavity, and perihepatic region.
- Infectious inflammation of the pelvic organs may lead to tissue necrosis and abscess formation. Eventually, the process evolves into scar formation with the development of adhesions to nearby structures.
- Acute PID (salpingitis) is a typical clinical syndrome.
- Chronic PID is an outdated term that refers to the long-term sequelae.
Etiology –
- The pathogenesis is incompletely understood but involves a polymicrobial infection ascending from the bacterial flora of the vagina and cervix.
- Chlamydia trachomatis and/or Neisseria gonorrhoeae is detectable in >50% of women. These pathogens are probably responsible for the initial invasion of the upper genital tract, with other organisms becoming involved secondarily.
- Fifteen percent of cases follow a surgical procedure (endometrial biopsy, intrauterine device [IUD] placement) which breaks the cervical mucus barrier and directly transmits bacteria to the upper genital tract.
Risk factors –
- The classic example of a high-risk patient is a menstruating teenager who has multiple sexual partners, does not use contraception and lives in an area with a high prevalence of STIs.
- Seventy-five percent of women diagnosed are <25 years.
- Premenarchal, pregnant, or postmenopausal patients are rare.
- Having multiple partners increases the risk by fivefold.
- Frequent vaginal douching increases the risk by threefold.
- Barrier (condom, diaphragm) contraception decreases the risk.
- IUD insertion is a risk factor in the first 3 weeks after placement.
- Previous PID is a risk factor for future episodes: 25% of women will develop another infection.
Epidemiology –
- 1 million women in the USA (200,000 in the UK) are diagnosed annually.
Symptoms and Signs –
- PID can occur and cause serious harm without causing any noticeable symptoms.
- Lower abdominal pain is the most common complaint.
- Patients may also have fever, painful intercourse, irregular menstrual bleeding, nausea, and vomiting.
- Seventy-five percent have a mucopurulent cervical discharge on examination.
- Five percent present with Fitz–Hugh–Curtis syndrome (perihepatic inflammation and adhesions), characterized by pleuritic right upper quadrant pain.
Diagnosis –
- The Centers for Disease Control and Prevention (CDC) recommends diagnosis by minimal criteria of lower abdominal pain and uterine/adnexal tenderness or cervical motion tenderness on exam.
- Supportive criteria include temperature >101°F, mucopurulent cervical or vaginal discharge, abundant white blood cells (WBCs) on saline wet-mount, elevated C-reactive protein (CRP), elevated erythrocyte sedimentation rate (ESR), and positive gonorrhea or chlamydia testing.
- Confirmatory criteria traditionally include plasma cell endometritis on endometrial biopsy and visualization on laparoscopy. The sensitivity and specificity of these “gold standard” criteria are debated.
- Women meeting the criteria for PID may have a separate pathologic process (appendicitis, endometriosis, rupture of an adnexal mass) or a normal pelvis in up to 50% of cases.
Treatment of acute PID
- Antibiotic treatment should be started as soon as possible.
- Patients may be managed as outpatients or inpatients, depending on their clinical picture.
- Tubo-ovarian abscesses (TOAs) should be drained percutaneously or surgically.
- Management should include treatment of sexual partners, screening for other sexually transmitted infections, and education on the prevention of re-infection.
Surgical Management –
- Ruptured TOAs are a surgical emergency. The mortality risk is 5–10% chiefly due to the development of septic shock and adult respiratory distress syndrome.
- Patients with a TOA that do not respond to antibiotics and percutaneous drainage also require surgery.
- Bilateral salpingo-oophorectomy with hysterectomy yields the highest chance of success. Leaving any of the reproductive organs in situ risks re-emergence of infection, but conservative surgery should be considered in young patients who desire future fertility.
Long-term sequelae of PID –
Although the acute infection may be treated successfully, subsequent effects are often permanent. This makes early identification very important in preventing damage to the reproductive system.
- Infertility occurs in 10–15% of women with a single episode of PID and depends on the severity of the infection.
- Chronic PID is a recurrent pain syndrome that develops in 20% of women as a result of inflammation.
- Ectopic pregnancy is increased six- to tenfold.
Rare Causes –
Actinomycosis
- Actinomyces israelii is an anaerobic, Gram-positive, non-acid-fast, pleomorphic bacterium.
- The diagnosis should be suspected if such organisms are identified on cervical Gram stain or if an endometrial biopsy shows “sulfur granules.” However, definitive diagnosis requires a positive culture.
- Treatment. High-dose parenteral penicillin plus oral doxycycline for 6 weeks.
Pelvic Tuberculosis
- A common cause of chronic PID and infertility in developing countries.
- Mycobacterium tuberculosis is the causative agent.
- Definitive diagnosis requires histologic evidence of granulomas, giant cells, and caseous necrosis.
- Treatment. Multiple antituberculosis drugs for 18–24 months.