Clinical Guide > Comorbidities and Complications > PID

Pelvic Inflammatory Disease

January 2011

Chapter Contents


Pelvic inflammatory disease (PID) is the syndrome resulting from the ascent of microorganisms from the vagina and cervix to the uterine endometrium, fallopian tubes, ovaries, or contiguous abdominal structures. Many episodes of PID go unrecognized, because of lack of symptoms or mild, nonspecific symptoms (e.g., dyspareunia, abnormal bleeding, and vaginal discharge). Infecting organisms may include Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT), which are sexually transmitted, as well as anaerobic bacteria (Gardnerella vaginalis or Haemophilus influenzae), gram-negative rods (Escherichia coli), Streptococcus agalactiae, gastrointestinal flora, and mycoplasmas (Mycoplasma hominis). It is thought that PID generally is caused by sexually transmitted infections (STIs) and that additional organisms become involved after infection spreads and protective immunological barriers are disrupted.

Between 20% and 40% of women with cervical chlamydial infection and 10-20% of women with gonococcal infection eventually develop PID, but accurate estimates of the incidence of PID and infertility resulting from GC and CT are difficult to obtain. Hospitalizations for PID declined steadily throughout the 1980s and 1990s but remained relatively constant between 2000 and 2006, at approximately 80,000 annually.

PID is co-epidemic with HIV among some urban populations of reproductive age. Data on PID outcomes among HIV-infected women are limited. Many studies have documented no difference in length or severity of lower abdominal pain, vaginal discharge, fever, abnormal vaginal bleeding, or low back pain between HIV-infected and HIV-uninfected women with PID. However, there is a higher rate of tubo-ovarian abscesses and severe salpingitis and pyosalpinx among HIV-infected women.

Clinical presentation may include salpingitis, endometritis, tubal and ovarian abscess, and pelvic peritonitis, although PID may present with subtle or mild symptoms even in HIV-infected women. Long-term complications of PID may include infertility, ectopic pregnancy, pelvic adhesions, and chronic pain. After a single episode of PID, a woman's risk of ectopic pregnancy increases sevenfold. Approximately 13% of women are infertile after a single episode of PID, 25-35% after two episodes, and 50-75% after three or more episodes.

Diagnosis of PID usually is based on clinical findings, and providers should maintain a low threshold for diagnosing and promptly treating this disease, as it can wreak havoc on a woman's reproductive health. All women who are diagnosed with PID should be tested for GC and CT.

S: Subjective

The patient may complain of mild-to-moderate lower abdominal pain and tenderness, pain with intercourse, vaginal discharge, fever, chills, heavy menstrual bleeding, or other abnormal vaginal bleeding.

Inquire about the following during the history:

O: Objective

Check vital signs with special attention to temperature (may be elevated or normal).

Perform a focused physical examination. Check abdomen (bowel sounds, distention, rebound, guarding, masses, suprapubic and costovertebral angle [CVA] tenderness); perform complete pelvic examination looking for abnormal bleeding or discharge; uterine, adnexal, or cervical motion tenderness; pelvic masses or adnexal enlargement.

A: Assessment

A partial differential diagnosis includes the following:

P: Plan

Diagnostic Evaluation

A diagnosis of PID usually is based on clinical findings; however, the following can support a diagnosis and help rule out other causes of abdominal pain:

Often, diagnosis must be made and treatment initiated on the basis of clinical criteria. Current guidelines identify three "minimal criteria" found on pelvic examination in patients with PID:

The following signs support a diagnosis of PID:

Definitive diagnosis may be made on the basis of:


Because clinical diagnostic criteria for PID are not always conclusive, presumptive diagnosis and early empiric treatment is common. The positive predictive value of a clinical diagnosis is 65-90%.

Empiric therapy for PID should be started in women who have one or more of the minimal criteria, plus pelvic or lower abdominal pain and risk factors for PID (sexually active young women, women at risk of STIs), unless another cause for the symptoms is identified.

Treatment considerations

Antimicrobial regimens must be broadly effective against likely pathogens (see below). HIV-infected women appear to respond as well to standard antibiotic regimens as do HIV-uninfected women. It is not known whether HIV-infected women with advanced immunosuppression should be treated more aggressively; decisions about whether to use oral or parenteral therapy must be individualized.

Resistance to fluoroquinolone by GC is widespread in the United States and elsewhere; thus, this class of antibiotics is no longer recommended for treatment of PID.

No evidence suggests that IUDs should be removed in women diagnosed with PID. However, caution should be used if the IUD remains in place, and close clinical follow-up is recommended.

The goals of treatment include the following:

Indications for hospitalization of patients with PID include the following:


If the patient is pregnant, aggressive treatment is essential to prevent preterm delivery, fetal loss, and maternal morbidity. Some medications should be avoided to reduce the risk of fetal toxicity; these include doxycycline and gentamicin. Hospitalization for parenteral antibiotic therapy is recommended.

Antibiotic Regimens

Recommended Oral/Outpatient Regimens
Alternative Oral Regimens

If parenteral cephalosporin therapy is not feasible, consult with an expert. Some evidence supports the use of amoxicillin/clavulanic acid with doxycycline, and azithromycin with or without metronidazole or ceftriaxone. Because of the prevalence of fluoroquinolone-resistant GC, use of fluoroquinolones is no longer recommended but may be considered, with or without metronidazole, if the community prevalence and patient's risk of gonorrhea is low. For more information, see the CDC STD Treatment Guidelines (see "References," below).

Recommended Parenteral Regimens
Alternative Parenteral Regimen

Women who are started on oral antibiotics but do not respond within 72 hours should be reevaluated to confirm the diagnosis of PID and should be administered parenteral therapy on either an outpatient or inpatient basis. Patients who are treated with parenteral antibiotics usually can be transitioned to oral antibiotics within 24 hours of clinical improvement.


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