Adolescent Health Care: A Practical Guide

Chapter 63

Pelvic Inflammatory Disease

Lydia A. Shrier

Pelvic inflammatory disease (PID) is an ascending polymicrobial infection of the female upper genital tract and includes endometritis, parametritis, salpingitis, oophoritis, tuboovarian abscess (TOA), peritonitis, and perihepatitis. Neisseria gonorrhoeae and Chlamydia trachomatis are usually the causative agents of PID, but vaginal and enteric microorganisms also contribute to its pathogenesis. Approximately 20% of women with PID experience at least one long-term consequence, such as chronic pelvic pain, ectopic pregnancy, or infertility. Intervention efforts aimed at preventing PID during adolescence focus on primary prevention of all sexually transmitted diseases (STDs) and secondary prevention through aggressive screening for and early treatment of gonorrhea and chlamydial infection. The rates of U.S. cases of gonorrhea, chlamydial infection, and hospitalization for PID decreased during the 1990s. Although it is likely that the overall rate of PID decreased, there has also been a shift in the management of most cases of PID from the inpatient to the outpatient setting.

Etiology

Risk Factors

  1. Age: Adolescents account for 33% of all cases of PID, and women younger than 25 years account for 70% of cases. Both biological and behavioral factors explain the tenfold increased risk of PID and threefold increased risk of gonococcal or chlamydial infection among sexually active adolescents compared with that of adults.
  2. Cervical ectropion: The erythematous ring around the cervical os that is commonly seen on speculum examination of adolescents, represents the transitional zone between the columnar and squamous epithelium. Cells in this zone are highly susceptible to STDs. During childhood, the transitional zone is located in the distal vagina. By adulthood, it usually recedes into the more protected environment of the endocervical canal.
  3. Cervical secretory immunoglobulin A: The levels are lower during adolescence than adulthood owing to the lower prevalence of past exposure to immunogenic factors.
  4. Cervicitis with N. gonorrhoeae or C. trachomatis: Female adolescents have the highest rates of chlamydial infection of any age–sex group. Chlamydial infection is frequently asymptomatic and therefore can evolve into PID without prior symptoms prompting the infected young woman to seek early treatment. Adolescents with a gonococcal or chlamydial infection of the endocervix may have a 30% increased risk of PID.
  5. Sexual and other health risk behaviors: Adolescents frequently engage in behaviors associated with increased rates of STDs and PID including unprotected intercourse, frequent intercourse, multiple sex partners, intercourse during menses, smoking, alcohol and other drug use, and douching.
  6. Age at first intercourse: Risk for STDs is inversely related to adolescent age at coitarche.
  7. Previous PID: A history of previous PID increases the risk of subsequent PID 2.3 times. At least one in five females with PID will experience a subsequent episode.
  8. Race: Nonwhite adolescents are 2.5 times more likely to develop PID than white adolescents.
  9. Contraceptive methods
  10. Condom: Inconsistent condom use is associated with a two to three time increased risk of PID.
  11. Spermicide: Nonoxynol-9 promotes cell wall destruction of N. gonorrhoeaeand C. trachomatis.
  12. Oral contraceptives: Oral contraceptive use may decrease the risk of PID by thickening the cervical mucus and by decreasing cervical dilation, uterine contraction, and blood flow during menses. However, oral contraceptives have been associated with an increased risk of chlamydial infection and not all studies have found that oral contraceptives reduce the risk of PID.
  13. Intrauterine device (IUD): Women who have an STD at the time of IUD insertion have a greater, although still low risk of PID than women who are free of infection. The use of the more recently developed IUDs appear to carry a far lower risk of PID than the earlier systems. The risk is concentrated in the first 3 weeks after insertion of the IUD and then declines rapidly. Overall, the current risk of PID with IUDs is rare (1 in 1,000). There is no evidence that IUDs should be removed in women with acute PID. IUDs may be associated with increased risk of failed conservative treatment and need for surgical treatment of PID (Viberga et al 2006).

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  1. Bacterial vaginosis (BV): BV may facilitate ascension of organisms pathogenic for PID to the upper genital tract. BV has been associated with PID after first-trimester therapeutic abortion, as well as third-trimester preterm delivery. However, longitudinal studies have not consistently supported an association between BV and PID.
  2. Menses: Menses may be associated with an increased risk of ascending infection because of the loss of the cervical mucus plug, shedding of the endometrium, presence of menstrual blood (a good culture medium), and/or occurrence of myometrial contractions resulting in reflux of blood into the fallopian tubes.

Microbiology

PID is a polymicrobial infection that usually begins with a sexually transmitted organism such as N. gonorrhoeae or C. trachomatis but involves other organisms as well, such as anaerobes. Organisms isolated from the upper genital tract of women with PID include the following:

  1. N. gonorrhoeae:Twenty-five percent to 50% of women with PID have evidence of upper tract gonococcal infection, and of these, 40% also have evidence of chlamydial infection. The likelihood of positive endocervical test results for gonorrhea is three times higher among women with PID who present within the first 24 hours of symptoms than among women who present after 48 hours.
  2. C. trachomatis:Ten percent to 43% of women with PID are reported to have evidence of upper tract chlamydial infection. However, because laboratory testing for C. trachomatishas improved dramatically over the last decade, it is likely that the rates are higher than those previously reported.
  3. Bacteroidesspecies and other anaerobes: Fifty percent of women with PID have evidence of upper tract infection with anaerobic organisms.
  4. Escherichia coli, Streptococcusspecies, and other facultative bacteria
  5. Mycoplasma hominisand Ureaplasma urealyticum

Pathogenesis

  1. After lower tract infection with N. gonorrhoeaeor trachomatis, the normal vaginal lactobacilli are supplanted by anaerobes, facultative bacteria, and genital mycoplasmas.
  2. Inflammatory disruption of the cervical barrier facilitates ascension of the inciting sexually transmitted pathogens and other microorganisms from the vagina into the normally sterile uterus. Plasma cell infiltration of the endometrium is the hallmark of PID.
  3. Decreased tubal motility secondary to inflammation results in collection of fluid (hydrosalpinx) or pus (pyosalpinx) within the tube.
  4. Spillage of infected contents from the tubal fimbriae into the peritoneal cavity may result in the following:
  5. Peritonitis
  6. Perihepatitis (Fitz-Hugh-Curtis syndrome): Infected material tracks along the paracolic gutter. Inflammation of the hepatic capsule and diaphragm causes right-upper-quadrant (RUQ) pain and referred right subscapular pain. Liver function study results are normal or minimally elevated and nonspecific markers of inflammation, such as the erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) may be higher than is typically seen in mild, uncomplicated PID.
  7. TOA: TOA develops if resolution of the upper tract infection is delayed or if previous tubal scarring occludes the tube. The abscess can form in the tube or between the tube and ovary. Estimates of TOA formation range from 7% to 19% of women with PID.
  8. Adhesions: As PID resolves, scar tissue may form in the tube, between the tube and ovary, or in the peritoneal cavity. Adhesions are the cause of subsequent infertility, ectopic pregnancy, and chronic pain.

Presenting Signs and Symptoms

Classically, PID presents with lower abdominal or pelvic pain, abnormal vaginal and/or cervical discharge, and fever and chills, with leukocytosis and increased ESR. However, this constellation of signs and symptoms is seen in approximately one in five laparoscopically verified cases of PID. Subclinical infection likely accounts for most cases of PID; more than 70% of women with infertility from bilateral tubal occlusion have serum antibodies to C. trachomatis and approximately 60% do not report a history of PID.

  1. Pelvic or abdominal pain: More than 80% of adolescents with PID present with pelvic or abdominal pain and 50% to 75% of those with pain present within 7 days of menses. The pain of PID is constant, cramping, and exacerbated by walking and intercourse.
  2. Abnormal vaginal bleeding: The endometritis of PID is associated with irregular, prolonged, and/or heavy vaginal bleeding in 35% of patients with PID. Unlike with anovulation, the most common cause of irregular bleeding during adolescence, bleeding due to PID is painful.
  3. Vaginal discharge: Cervicitis and/or vaginitis cause an abnormal discharge in approximately 50% of patients with PID.
  4. Gastrointestinal (GI) symptoms: Peritonitis may cause an ileus with anorexia, nausea, or vomiting. Severe vomiting is not common in PID and should suggest a careful exploration of another GI problem.

Other history, signs, and symptoms compatible with a diagnosis of PID include dysuria or urinary frequency, dyspareunia, onset of symptoms within 1 week of menses, and a sexual partner with recent urethritis.

Findings on Physical Examination

  1. Vital signs: Temperature higher than 38°C is present in 40% of patients with laparoscopically verified PID. Tachycardia secondary to the pain and fever is common.
  2. Abdomen: Tenderness to palpation of the lower abdomen, with or without rebound and guarding.
  3. Pelvic examination
  4. Abnormal vaginal or cervical discharge
  5. Friable, inflamed cervix
  6. Cervical motion tenderness (present in >80% of patients with PID)
  7. Adnexal tenderness (unilateral or bilateral)
  8. Palpation of an adnexal mass (5% to 60%)
  9. Uterine tenderness (common)

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Laboratory and Radiological Evaluation

No single test is diagnostic of PID. The following laboratory and radiological tests should be considered in the evaluation of suspected PID.

  1. White blood cell (WBC) count: Elevated in 30% to 67% of patients with PID.
  2. ESR (or CRP): An ESR of >15 mm/hour is found in 75% to 80% of patients with PID.
  3. Saline wet mount of vaginal secretions: Most women with PID have either mucopurulent cervical discharge or WBCs on microscopic examination of a saline wet mount of vaginal secretions (90.9% sensitive, 26.3% specific for PID). The absence of any leukocytes in the secretions suggests a diagnosis other than PID (negative predictive value is 94.5%).
  4. Microbiological tests: Presumptive diagnosis and treatment of PID should not await microbiological test results. Positive results for N. gonorrhoeaeor trachomatis infection support but do not confirm the diagnosis of PID and negative results do not eliminate the diagnosis.
  5. Specimens should be collected and sent to the laboratory before initiating antibiotic therapy.
  6. Because a pelvic examination is required for the diagnosis of PID, endocervical, rather than vaginal or urine specimens, are preferred.
  7. The specimens should be examined for N. gonorrhoeaeand trachomatis, but not for anaerobes, mycoplasmas, or enteric organisms that normally colonize the vagina.
  8. The preferred test for N. gonorrhoeaein patients with suspected PID is either endocervical cell culture or a nucleic acid amplification test (NAAT), such as polymerase chain reaction (PCR), transcription-mediated amplification (TMA), or strand displacement amplification (SDA).
  9. The preferred test for trachomatisin patients with suspected PID is a NAAT.
  10. Urinalysis and urine culture: To evaluate for possible urinary tract infection/pyelonephritis.
  11. Urine pregnancy test. If positive, an ectopic pregnancy must be considered.
  12. Human immunodeficiency virus (HIV) testing: All patients with STDs should be offered HIV counseling and testing.
  13. Pelvic ultrasonography: Used if the clinician cannot adequately assess the adnexa, palpate an adnexal mass, or questions the presence of an ectopic pregnancy or TOA. Ultrasonography (especially if performed transvaginally) can be useful in narrowing the differential diagnosis, but is a relatively insensitive test for PID.
  14. Laparoscopy: Indicated diagnostically in the patient whose pain does not respond to antibiotic therapy and therapeutically in the patient with a persistent TOA.

Diagnosis

Timely and accurate diagnosis of PID is essential in preventing sequelae. Depending on the criteria used and the epidemiological characteristics of the patient population, the positive predictive value of a clinical diagnosis of PID, using laparoscopic diagnosis as the gold standard, ranges from 65% to 90%. The differential diagnosis is broad (Table 63.1).

TABLE 63.1
Differential Diagnosis of Pelvic Inflammatory Disease

Gastrointestinal

  Appendicitis

  Cholecystitis

  Cholelithiasis

  Constipation

  Diverticulitis

  Gastroenteritis

  Hernia

  Inflammatory bowel disease

  Irritable bowel syndrome

Gynecological

  Corpus luteum cyst

  Dysmenorrhea

  Ectopic pregnancy

  Endometriosis

  Mittelschmerz

  Ovarian

   Cyst

   Torsion

   Tumor

  Pregnancy

   Ectopic

   Spontaneous, septic, or threatened abortion

   Postabortion endometritis

Urological

  Cystitis

  Nephrolithiasis

  Pyelonephritis

  Urethritis

Musculoskeletal

Rheumatologic/autoimmune

Psychiatric

The Centers for Disease Control and Prevention (CDC) has made recommendations on the use of minimum and elaborate criteria for the diagnosis of PID (Table 63.2). These recommendations for diagnosing PID are intended to help health care providers recognize when PID should be suspected and when additional information is needed to increase diagnostic certainty. PID should be considered as a likely diagnosis in any woman with pelvic tenderness and signs or symptoms of lower genital tract inflammation. Empirical treatment should be initiated in young women at risk for STDs if any of the minimum criteria is present and no other cause(s) for the illness can be identified.

The CDC urges that clinicians maintain a low threshold for the diagnosis and empirical treatment of PID. However, because incorrect diagnosis and management can cause unnecessary morbidity, more elaborate diagnostic criteria may be used to enhance the specificity of the minimum criteria.

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TABLE 63.2
Centers for Disease Control and Prevention Diagnostic Criteria for Pelvic Inflammatory Disease

Minimum criteria (initiate treatment in females at risk for STDs and complaining of lower abdominal pain when one or more clinical sign is present and no other diagnosis is apparent)

  Cervical motion tenderness, OR

  Uterine tenderness, OR

  Adnexal tenderness

Additional criteria (support a diagnosis of PID)

  Oral temperature >101°F (>38.3°C)

  Abnormal cervical or vaginal mucopurulent discharge

  Presence of abundant numbers of white blood cells on saline microscopy of vaginal secretions

  Elevated erythrocyte sedimentation rate

  Elevated C-reactive protein level

  Laboratory documentation of cervical infection with N. gonorrhoeae or C. trachomatis

Definitive criteria (warranted in selected cases)

  Endometrial biopsy with histopathological evidence of endometritis

  Transvaginal sonography or magnetic resonance imaging techniques showing thickened, fluid-filled tubes with or without free pelvic fluid or tuboovarian complex, or Doppler studies suggesting pelvic infection (e.g., tubal hyperemia)

  Laparoscopic abnormalities consistent with PID

Therapy

PID requires treatment with broad-spectrum antibiotics as soon as a presumptive diagnosis is made. CDC-recommended treatment regimens for PID are summarized in Tables 63.3 and63.4. Fluoroquinolones are no longer recommended for the treatment of PID due to increased prevalence of gonococcal resistance.

CDC criteria for hospitalization are as follows:

  1. Surgical emergencies such as appendicitis cannot be excluded
  2. Pregnancy
  3. Poor response to oral antimicrobial therapy
  4. Inability to follow or tolerate an outpatient oral regimen
  5. Severe illness, nausea and vomiting, or high fever
  6. TOA (at least 24-hours inpatient followed by outpatient antimicrobial therapy for a total of at least 10 days)
  7. Immunodeficiency (e.g., HIV infection with low CD4 counts, immunosuppressive therapy)

Other reasons to consider hospitalization in the adolescent with suspected PID include age <15 years, abortion or other gynecological surgery procedure within previous 14 days, a history of a previous episode of PID, and other extenuating medical or social circumstances that may preclude receipt of appropriate treatment as an outpatient.

TABLE 63.3
CDC-Recommended Parenteral Antibiotic Regimens for Pelvic Inflammatory Disease

1.  Cefotetan 2 g IV every 12 hr or cefoxitin 2 g IV every 6 hr, plus doxycycline 100 mg PO or IV every 12 hr

2.  Clindamycin 900 mg IV every 8 hr plus gentamicin loading dose IV or IM (2 mg/kg of body weight), followed by a maintenance dose (1.5 mg/kg) every 8 hr (single daily dosing may be substituted)

3.  Alternatives

Ampicillin/sulbactam 3 g IV every 6 hr plus doxycycline 100 mg PO or IV every 12 hr Parenteral therapy can be discontinued 24 hours after clinical improvement. Therapy should be continued with doxycycline 100 mg PO twice a day or clindamycin 450 mg PO four times a day to complete a total of 14 days of therapy

Among women with mild-to-moderate PID, there does not appear to be any difference in reproductive outcomes between inpatient and outpatient treatment. Whether treatment is provided is an inpatient or outpatient setting, the following general recommendations should be considered:

  1. Patients should be educated about the importance of completing a full 14-day course of antibiotics. The duration of treatment does not depend on the result of any laboratory test.
  2. All sex partners within the preceding 60 days require treatment for trachomatisand N. gonorrhoeae infections, regardless of patient or partner microbiological test results.
  3. The use of nonsteroidal anti-inflammatory drugs is recommended to treat abdominal pain or cramping.
  4. In the setting of TOA, clindamycin or metronidazole with doxycycline is used as continued therapy for expanded anaerobic coverage.

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  1. Single-dose azithromycin (used for treatment of chlamydial cervicitis or urethritis) has not been shown to be effective for the treatment of PID.

TABLE 63.4
CDC-Recommended Oral Regimens for Pelvic Inflammatory Disease

Ceftriaxone 250 mg IM in a single dose or

Cefoxitin 2 g IM and probenecid 1 g PO concurrently in a single dose or another parenteral third-generation cephalosporin (e.g., ceftizoxime or cefotaxime), plus doxycycline 100 mg PO twice a day for 14 days with or without metronidazole 500 mg PO twice a day for 14 days

If a parenteral regimen is used, the following points should be considered:

  1. Patients who do not improve clinically within 72 hours require further evaluation and possibly surgical intervention.
  2. Intravenous doxycycline should be avoided because of pain and venous sclerosis with infusion.
  3. Cephalosporins other than cefotetan or cefoxitin are less active against anaerobes and are not recommended.

Adolescents with PID who are treated as outpatients, should have a follow-up examination within 72 hours to document defervescence and improvement in pain. If the baseline C. trachomatis and/or N. gonorrhoeae tests are positive, repeated screening for reinfection is warranted 4 to 6 weeks after the completion of therapy.

Consequences

  1. Recurrence: Reported rates vary from 12% to 33%. Risk is inversely correlated with treatment of sexual contacts.
  2. TOA: May occur in as many as one third of women hospitalized with salpingitis. Antibiotic therapy is effective in 42% to 92% of cases. Surgical therapy is indicated for rupture or ultrasound evidence of increasing size or nonresponse.
  3. Infertility: One episode of PID is associated with a 13% to 21% risk; two episodes, a 35% risk; and three or more episodes, a 55% to 75% risk. It is important to counsel an adolescent who has had PID about the risk of infertility. If the risk of possible infertility is overemphasized, the adolescent may assume that she is unable to conceive or may not use effective contraception in an effort to test her fertility.
  4. Ectopic pregnancy: PID is the single most common predisposing factor for ectopic pregnancy. One episode of PID increases the risk of ectopic pregnancy six- to ten-fold.
  5. Chronic abdominal and/or pelvic pain: Dysmenorrhea and dyspareunia occur in up to 18% of women after one episode of PID.

Prevention

  1. Primary prevention involves education about STD prevention and aggressive screening of all sexually active adolescents.
  2. Education about the signs and symptoms of STDs, the consequences of STDs, and behaviors that increase or decrease the risk should begin early.
  3. Communities must prioritize the establishment and maintenance of comprehensive STD control strategies that include health promotion, as well as confidential clinical service.
  4. Secondary prevention focuses on those adolescents with a history of PID.
  5. Counseling should begin with the initiation of antibiotic therapy. If the adolescent is hospitalized, the inpatient stay provides an important opportunity for intense education and discussion.
  6. Sex partners should be included in secondary counseling and education.
  7. Prevention continues after treatment, with the promotion of secondary abstinence or safer sexual behaviors.

Acknowledgments

Dr. Shrier is supported in part by grant #1 R21 MH072533-01A1 (Shrier) from the National Institute of Mental Health, National Institutes of Health, and Leadership Education in Adolescent Health grant #5 T71 MC 00009 from the Maternal and Child Health Bureau, Health Resources and Services Administration.

Web Sites

For Teenagers and Parents

http://www.youngwomenshealth.org/pid.html. The Center for Young Women's Health of Children's Hospital Boston handout, available in English and Spanish.

http://www.mckinley.uiuc.edu/health-info/womenhlt/pid.html. University of Illinois Health Center handout.

http://womenshealth.gov/faq/stdpids.htm. The National Women's Health Information Center Web site.

http://www.engenderhealth.org/wh/inf/dpid.html. Engender Health worldwide women's health Web site.

http://www.cdc.gov/std/PID/STDFact-PID.htm. CDC patient information sheet, available in English and Spanish.

For Health Professionals

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5511a1.htm. Sexually Transmitted Diseases Treatment Guidelines 2006 from the CDC.

http://www.emedicine.com/med/topic1774.htm. eMedicine Web site.

http://edcenter.med.cornell.edu/CUMC_PathNotes/Female_Genital_Tract/FGT_2.html. Cornell University teaching slides on female genital tract.

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