Chronic Pelvic Pain

By Geri D. Hewitt, MD, and Robert T. Brown, MD

Reprinted by permission from Contemporary Adolescent Gynecology Magazine.

Whether the source is physical or psychosocial or both, the impact is real and serious for the teenager. She needs symptomatic relief, sympathy, and support while you explore a variety of possible causes.

Chronic pelvic pain is classically described as noncyclic pain of at least 6 months' duration. In the adolescent, this condition often frustrates the patient, her parents, and her clinician. Such pain also can lead to changes in family dynamics, school absenteeism, and other significant functional problems. The young woman with chronic pelvic pain may visit several physicians in search of specific diagnoses, effective treatments, and relief of her symptoms. Over a period of time, she might in turn see a pediatrician, gynecologist, gastroenterologist, and emergency department doctor.

Anatomy of pain perception
Understanding chronic pelvic pain begins with understanding how and why patients respond to painful stimuli. Several models have been proposed. One is the classic medical or Cartesian model, which postulates that pain perception results directly from and is related to the extent of local tissue destruction. According to this model, pain in the absence of tissue injury is psychogenic. Unfortunately, while this theory may help us understand acute causes of pain such as appendicitis, its omission of nonorganic causes makes it a poor model for chronic pain syndromes.

Many studies have documented that psychological and social factors predict a patient's response to painful stimuli as well as or better than does the amount of tissue destruction. The gate-control theory of pain therefore provides a better model for chronic pelvic pain because it integrates peripheral stimuli with variables such as depression or anxiety that influence the patient's perception of pain. In this model, both somatic and psychogenic factors can potentiate or modify response to pain. However, the gate-control theory falls short by failing to recognize the many social factors believed to affect a patient's responses to pain and to therapy. These factors include familial response to pain as well as the patient's level of educational attainment and socioeconomic status.

The biopsychosocial theory of pain perhaps provides the most comprehensive model for dealing with chronic pelvic pain in the adolescent. It was developed to try to integrate all the factors that contribute to a patient's perception of pain: nociceptive stimuli, psychological state, and social determinants. This model also explains a phenomenon called symptom "shifting," often seen in patients with chronic pain syndromes. In symptom shifting, removing the nociceptive (mechanical, thermal, or chemical) stimuli but failing to address psychological or social concerns may cause the patient to develop symptoms at an alternative site. Thus, the young woman whose pelvic pain appears to be cured by medical therapy may start to experience headaches. Similarly, a woman who undergoes a surgical intervention that temporarily alleviates her symptoms may suffer pain elsewhere or a relapse of her pelvic pain with even more disabling symptoms.¹

In evaluating an adolescent with chronic pelvic pain it's therefore important to recognize that a variety of somatic, psychological, and social factors may, alone or in combination, play a role in the pain syndrome. Several authorities have emphasized the value of examining these variables concomitantly from the very start of the evaluation.² One prospective, randomized trial compared patients considered for both organic and psychosocial causes of pain at the initial visit with patients considered for psychosocial causes only after organic pathology had been ruled out. Patients in the first group had not only better responses to therapies but also improved long-term outcome.³

The range of organic causes
Gynecologic disorders. The broad differential diagnosis for organic sources of chronic pelvic pain in adolescence includes gynecologic, urologic, gastroenterologic, and musculoskeletal causes (TABLE 1). Gynecologic possibilities include adnexal lesions, such as ovarian tumors or chronic ectopic pregnancy; infectious causes such as pelvic inflammatory disease (PID) or tubo-ovarian abscess (TOA); and endometriosis, which may be associated with Müllerian anomalies. Whether pelvic adhesive disease causes chronic pelvic pain is somewhat controversial, since the incidence of adhesions is the same for patients undergoing laparoscopy for chronic pelvic pain as for women undergoing laparoscopy for elective sterilization. However, many authors suggest that adhesions that impinge on or limit organ function (for example, by restricting bowel motility) may cause pain. Until this relationship is demonstrated, it's advisable to counsel patients that adhesions may or may not be the cause of pain, that surgical lysis of adhesions may or may not relieve pain, and that adhesions may reform at old sites or form de novo.

Ultrasound evaluation for chronic pelvic pain often reveals physiologic or functional ovarian cysts. Such cysts may be present even in premenarcheal girls who have low levels of circulating gonadotropins. However, it's important to resist concluding that these cysts are the cause of the pain. This assumption may cause other, more likely causes to be overlooked. It may also lead to unnecessary surgery. In the vast majority of patients, ovarian cysts are not the source of the pain and will resolve either spontaneously or with suppression when using oral contraceptives (OCs). Adolescents operated on for ovarian cysts, particularly premenarcheal girls, often end up with an oophorectomy even if the surgeon's preoperative intention was to do only a cystectomy. Even if the patient's cystectomy preserves her ovaries, she may be at risk for adhesion formation that may lead to infertility.

Urologic sources. Urinary tract infection (UTI) is a common cause of pelvic pain in adolescent females. UTIs can present with abdominal pain, dysuria, and/or hematuria and, if untreated, can progress to pyelonephritis. Kidney stones, interstitial cystitis, and urethral syndrome, while much less common than UTI, should also be ruled out.

Gastroenterologic causes. Because the pelvic organs and lower GI tract share visceral innervation, various GI causes may be contributing to the pain and need to be considered. Some of these causes can be diagnosed according to symptoms and the physical examination; others require abdominal films or endoscopy. Constipation, for example, is the most common problem, particularly if the patient's diet is poor. It can be diagnosed easily by physical exam and abdominal films and easily corrected by increasing hydration and dietary fiber intake. A dietary history is also important when evaluating a patient for lactose intolerance.

Irritable bowel syndrome is another condition often encountered in young women being evaluated for chronic pelvic pain. Keep in mind that adolescents with chronic pelvic pain and those with irritable bowel syndrome share a higher risk for stress-related psychopathologies such as somatization, depression, and anxiety. Peptic ulcer disease, gastroenteritis, and inflammatory bowel disease also should be considered and may be diagnosed by endoscopy. Chronic appendicitis and hernias may require a consultation with a general surgeon for correction.

Musculoskeletal problems. Musculoskeletal abnormalities can cause pelvic pain, usually because of an increase in muscle tone. Lumbar vertebrae, joint capsules, ligaments, discs, hip joints, and muscles such as the abdominals, iliopsoas, quadratus lumborum, piriformis, and obturator internus and externus are innervated from the T12 to L4 region of the spine and can refer pain to the lower abdomen and the anterior thigh. This pain can change in character as progesterone and relaxin levels fluctuate during the menstrual cycle.

The intensity and location of musculoskeletal pain may also shift in response to variations in posture or specific activities. Poor posture or leg-length discrepancy can produce mechanical stress on joint capsules, ligaments, and muscles that can lead to chronic pelvic pain. Trigger points - areas of hyperirritability within a skeletal muscle - also can give rise to referred pain and tenderness. Trigger points begin with a muscle strain, followed by sensitization of the nerve bundle. Pain from this source can be treated by injecting a local anesthetic.

Other musculoskeletal causes of pelvic pain include joint pain, inflammation, and spinal injury.

FIGURE 1 Model for sources of chronic pelvic pain

Adapted from Levine ME, Rappaport LA: Recurrent abdominal pain in school children. Pediatr Clin North Am 1984;31(5):969

Coping with psychogenic pain
Pelvic pain can be of psychosomatic origin in adolescence, a time of rapid change when awareness of bodily functions and sensations is heightened. It is also a time when the adolescent is encountering many new stressors. In addition to the stresses of rapid growth and development, there often are added school pressures, economic worries, and the problems of burgeoning sexuality. Adjusting to such stresses, even temporary ones, can induce physical symptoms. And stresses that don't go away - for example, those stemming from sexual abuse or parents divorcing - may produce significant physical symptoms, particularly if the adolescent's temperament or circumstances prevent her from coping well.

Coping style can also play a significant role in the development and persistence of psychosomatic symptoms.⁵ Some adolescents can cope proactively with stress. For example, when the home situation becomes intolerable, this type of adolescent can respond with a decisive action, possibly by running away. The adolescent who copes in a passive manner may show no immediate overt reaction to a stressor but may go on to exhibit chronic pain symptoms or fatigue.

Other factors that affect an adolescent's ability to cope with stress include lifestyle and major life events. A lifestyle of regularity— characterized by regular times for meals, regular study and exercise habits, and regular sleeping patterns— may enable an adolescent to cope more effectively with stresses when they occur. In contrast, the adolescent who is poorly organized and burns the candle at both ends may have more difficulty dealing with stress. Occurrence of a major stressful life event, such as moving, the death of a parent or sibling, or a natural disaster, may also severely challenge the ability of an adolescent to cope. When two or more of these events occur within a short time, the likelihood of maladaptive coping and the production of psychosomatic symptoms such as pelvic pain increase significantly.

In making the diagnosis, remember that family violence is not only very prevalent but has a wide variety of physical, behavioral, and emotional manifestations.^35,36 As shown in Table 1, many indicators are nonspecific, so you need to ask a few open-ended questions (see examples in Table 2) to obtain the information you need.³⁷ If you observe indicators of violence, follow up with screening and further assessment.

Figure 1 shows a variety of patient characteristics and circumstances can combine to produce psychosomatic symptoms. In this model, all the factors that can account for the appearance of psychosomatic symptoms are included, with their possible interactions.

History and diagnosis
History taking should emphasize the duration and frequency of symptoms, location and severity of pain, and medications and therapies tried. In addition to current medications, review past medical illness and surgeries. Also explore causes of exacerbation and improvement and ask whether other family members have had similar symptoms. Symptom modeling is a well-known phenomenon of psychosomatic problems. A prospective pain calendar can be useful in obtaining information; the patient should also record her menses to help identify any cyclic component.

Gynecologic history should include sexual activity, exposure to sexually transmitted diseases, age at menarche, menstrual irregularities, and gravidity and parity. Ask about any family history of endometriosis; patients with a first-degree relative with endometriosis face a 7% risk of the same diagnosis.⁵ Frequency, dysuria, or hematuria may suggest a urologic cause. Review dietary history, nausea or vomiting, and bowel habits to evaluate GI sources of pain. Psychosocial factors should also be reviewed carefully, with questions about history of depression, eating disorders, or substance abuse, as well as the number of school days missed. Assess coping style carefully, and ascertain occurrence of any recent major life changes.

A focused physical exam should be done to assess the various potential sources of pain. To screen for musculoskeletal causes of pain, examine the patient's posture to look for evidence of lordosis, one-legged standing, or leg-length discrepancy. Palpate the upper and lower back while the patient is sitting. Once she is supine, have her do leg flexion and head and leg raises while palpating her abdominal wall. Ask her to point to the area where the degree of pain is greatest. With psychosomatic pain, the adolescent typically has difficulty isolating a small area of pain origin.

While performing the pelvic exam, consider urologic as well as gynecologic causes of pain. Palpate the urethra and bladder base and note any specific tenderness. Also palpate the vaginal fornices for tenderness or masses. On bimanual exam, evaluate the uterus and explore for adnexa. A rectal examination is also essential, particularly if a GI source or endometriosis is suspected. If you detect a large mass of soft stool or if the patient has a wide rectal vault, suspect constipation.

Laboratory tests that should be included in the evaluation are complete blood cell count (CBC) with differential, urinalysis, urine culture sensitivity, and erythrocyte sedimentation rate (ESR). Add cervical cultures and b-hCG pregnancy testing for patients who are sexually active. A plain film of the abdomen is helpful if constipation is suspected. Reserve pelvic ultrasound for patients with an identified abnormality or compromised exam. Pelvic ultrasound should not be ordered routinely for pelvic pain, nor should it be used in place of a physical exam.

When to do laparoscopy
An advantage of laparoscopy is that in many conditions it can document the diagnosis as well as provide the route for therapy. It can be beneficial for certain adolescents with chronic pelvic pain but should be done only when indicated. Indications include a suspected organic lesion identified on physical exam or ultrasound, progressive dysmenorrhea or dysmenorrhea unresponsive to drug therapy, and unexplained painful irregular vaginal bleeding. It may also be needed for patients with suspected chronic PID; it should definitely be done when endometriosis is suspected (TABLE 2).

Endometriosis can be diagnosed only by laparoscopy, and it can often be treated at the time of diagnosis by either electrocoagulation or laser vaporization. Endometriosis has been documented as early as 6 months after menarche and in girls as young as 11 years old.⁶ Identifying and treating it early may decrease the patient's risk of pelvic adhesive disease and infertility. The diagnosis of endometriosis may also influence her choice of contraception and timing of pregnancy. In patients with endometriosis, a concomitant MŸllerian anomaly should be ruled out.

Findings at time of laparoscopy have varied, depending on patient selection, preoperative suspicion of endometriosis, and type of operator (general surgeon or gynecologist); in four studies, 56% to 88% of patients had identifiable lesions, most of which could be treated at the time of laparoscopy (TABLE 3).^6-9 In three of the four studies, in patients with organic pathology, endometriosis was the most common finding (TABLE 3).^6,8,9 In the fourth, no endometriosis was found, but this study was done in 1977 by general surgeons before there was a clear understanding that adolescents may have endometriosis and that its appearance in adolescents (clear vesicles) differs from that in adults (classic powder burns).⁷

In addition to endometriosis, other laparoscopic findings for chronic pelvic pain include PID, TOAs, pelvic adhesive disease, hemoperitoneum, ovarian cysts, pelvic tuberculosis, serositis, and paratubal cysts.

Up to 40% of adolescents undergoing laparoscopy for chronic pelvic pain will have no pathologic findings. Don't underestimate the value of negative findings in providing reassurance for the patient and her parents. Symptoms resolve in approximately 60% of patients after a negative laparoscopy for chronic pelvic pain. For optimal reassurance, have pictures showing normal anatomy of the uterus, fallopian tubes, ovaries, bladder, cul-de-sac, appendix, and liver edge taken during surgery and share them with the patient and her family. This reassurance is particularly helpful to a patient whose pain has a psychosomatic component.

When no clear cause is found
In the adolescent for whom laparoscopy is thought not to be indicated or in whom it has detected no organic abnormality, further management is needed. The best approach in these cases is to attend first to the patient's symptoms. From the first visit, even if no clear etiology is found, the physician can show serious concern for the patient by offering symptomatic relief. Simple measures such as applying heat to the abdomen, helping to regularize bowel movements, and offering an exercise program can be effective.

Listen attentively to the language the family uses to describe feelings about the girl's problems. If the family asks to have the pain fixed, describe the various ways that might be considered. Mention at the first visit the possibility that the pain might be of nonorganic origin. Validating this possibility early makes the assistance of a psychologist or social worker more palatable to the family and patient if that should become necessary. If you wait until all tests and procedures are finished before suggesting that a psychosocial factor might be the culprit, the family may interpret this as indicating that the physician thinks the problem is imaginary. Since the pain in her belly is obviously real, such a suggestion usually will send the patient to her next physician in the commonly seen phenomenon of doctor shopping.

By providing sympathy and support for the patient's symptoms and the family's concerns, the physician frequently can form a true therapeutic alliance that will alleviate the patient's disease even if the symptom is not totally relieved. Combined with judicious use of diagnostic technology, this approach should enable you to be successful in treating the majority of adolescents with chronic pelvic pain.

ACKNOWLEDGMENTS
The authors would like to thank Tracy Fox and Harold E. Regan, Jr., MA, for their technical assistance and diligence in completing this manuscript

REFERENCES

1. Rosenthal RH: Psychology of chronic pelvic pain. Obstet Gynecol Clin North Am 1993;20:627
2. Gambone JC, Reiter R: Nonsurgical management of chronic pelvic pain: A multidisciplinary approach. Clin Obstet Gynecol 1990;33:205
3. Peters AAW, van Dorst E, Jellis B, et al: A randomized clinical trial to compare two different approaches in women with chronic pelvic pain. Obstet Gynecol 1991;77:740
4. Ryan-WengerNM: Children's psychosomatic responses to stress, in Arnold LE (ed): Childhood Stress. New York, John Wiley & Sons, 1990, pp 110 - 137
5. Malinak LR, Buttram VC Jr, Elias S, et al: Heritable aspects of endometriosis: II. Clinical characteristics of familial endometriosis. Am J Obstet Gynecol 1980;137:332
6. Goldstein DP, de Cholnoky C, Emans SJ, et al: Laparoscopy in the diagnosis and management of pelvic pain in adolescents. J Reprod Med 1980;24:251
7. Kleinhaus S, Hein K, Sheran M, et al: Laparoscopy for diagnosis and of abdominal pain in adolescent girls. Arch Surg 1977;112:1178
8. Chatman DL, Ward AB: Endometriosis in adolescents. J Reprod Med 1982;27:156
9. Vercellini P, Fedele L, Arcaini L, et al: Laparoscopy in the diagnosis of chronic pelvic pain in adolescent women. JReprod Med 1989;34:827

Dr. Hewitt is assistant professor of clinical obstetrics and gynecology and Dr. Brown is professor of clinical pediatrics, Columbus Children's Hospital and The Ohio State University College of Medicine, Columbus, OH.

Copyright © 1999 Medical Economics Company. Reprinted by permission from Contemporary Adolescent Gynecology Magazine.