© Springer Science+Business Media New York 2015
Leonardo Kapural (ed.)Chronic Abdominal Pain10.1007/978-1-4939-1992-5_1010. Chronic Abdominal Pain of Gynecologic Causes: Diagnosis and Treatment
(1)
Department of Obstetrics & Gynecology, Minimally Invasive Gynecologic Surgeon, Kaiser Permanente, 27400 Hesperian Blvd., Hayward, CA 94545, USA
(2)
Department of Obstetrics and Gynecology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 668, Rochester, NY 14642, USA
(3)
Department of Obstetrics and Gynecology, Strong Memorial Hospital, University of Rochester Medical Center, 601 Elmwood Avenue, Box 668, Rochester, NY 14642, USA
Keywords
Chronic pelvic painDysmenorrheaDyspareuniaEndometriosisPelvic inflammatory diseaseIntroduction
Chronic pelvic pain (CPP) is a common disorder in women. One study from the United Kingdom found a prevalence of 3.8 % in women aged 15–73; higher than the prevalence of migraine (2.1 %) and similar to that of asthma (3.7 %) and back pain (4.1 %) [1]. Similarly a study in Seveso, Italy, found that 4 % of all women had moderate to severe, noncyclic pelvic pain [2]. A US study suggested a higher prevalence of 16 %, with a mean average pain score of 5, and 4 % with pain severe enough to cause them to miss work [3]. This study estimated that 9.2 million US women suffer from chronic pelvic pain.
Chronic pelvic pain leads to many medical interventions. It is the indication for 17 % of all hysterectomies in the United States [4] and more than 40 % of gynecologic diagnostic laparoscopies [5]. Overall, it is estimated that direct and indirect costs of chronic pelvic pain in the United States are over $2 billion per year [3]. At an individual level, chronic pelvic pain frequently leads to years of disability and suffering, with loss of employment, marital discord, and divorce.
CPP as defined by the American College of Obstetrics and Gynecology is nonmenstrual pain of 6 or more months’ duration that localizes to the anatomic pelvis, anterior abdominal wall below the umbilicus, or the lumbosacral back and causes functional disability or requires medical or surgical treatment [6]. This definition excludes vulvar pain and cyclical pain of dysmenorrhea. However, it is important to recognize that women with chronic pelvic pain often have vulvar pain or dysmenorrhea as part of their symptom complex.
There are a myriad number of gynecologic disorders that are associated with chronic pelvic pain [7]. As stated above, chronic abdomino-pelvic pain patients should always be evaluated for non-gynecologic sources of pain which are commonly found in this population. This chapter will focus on the more commonly diagnosed gynecologic diseases associated with pelvic pain: endometriosis, leiomyomata or uterine fibroids, adenomyosis, pelvic congestion syndrome, ovarian remnant syndrome, ovarian retention syndrome, and pelvic inflammatory disease (PID). Adhesive disease can also occur in the pelvis but postsurgical adhesions will be addressed in chapter XX. Because many women with CPP also have vulvar or vaginal pain, a few of the more important disorders associated with vulvar or vaginal pain—provoked vestibulodynia (previously vulvar vestibulitis) and pudendal neuralgia—will also be briefly reviewed.
History and Physical Examination
More than 80 % of women with chronic pelvic pain have had pain for longer than 1 year when they seek medical care, and about one third have had pain for longer than 5 years [8]. Making accurate diagnoses in women with CPP can be perplexing. There are numerous possible gynecologic and non-gynecologic diagnoses (only gynecologic will be covered in this chapter). Additionally, it is likely that chronic pain itself may need to be considered a diagnosis [9].
The history and physical examination are powerful diagnostic and therapeutic tools in chronic pelvic pain. As diagnostic tools, a thorough history and examination may lead to an accurate diagnosis. This process minimizes the need for expensive laboratory testing and imaging or risky operative interventions. It is important that the clinician remember that even a “routine” pelvic examination is emotionally stressful for many patients with chronic pelvic pain as the exam can be painful and often the patient has undergone numerous undesired exams. Establishing rapport and trust with a patient by a compassionately taken history and a sensitively performed examination ensures that the patient feels the physician is caring and competent. Often just by giving the patient the opportunity to express her frustration with the course of her symptoms and validating her suffering allows the patient to leave the physician’s office feeling better.
The history of the patient’s pain must be thoroughly explored and all pertinent imaging, pathology and operative records obtained, along with the review of systems, with particular attention to the gastrointestinal, reproductive, urologic, and musculoskeletal systems. Because of the complexity of the history in most patients, intake questionnaires are extremely helpful in obtaining details of the history (see, for example, www.pelvicpain.org). However, they should not replace allowing the patient to tell her story.
Establishing the location of the patient’s pain may be an important key to accurate diagnosis. Women with somatic nociceptive pain usually describe pain that is well localized to the area of disease. Such clear pinpointing is not always the case, however. For example, sometimes with levator ani pain the symptoms are described as deep, aching, heavy pain along with sharp, shooting pain and the patient cannot accurately localize the pain to the pelvic floor muscles. With visceral nociceptive pain there is almost always poor localization and usually a description of deep, dull, and cramping pain. Furthermore, because the cervix, uterus, and adnexae have the same metameric innervation as the bladder, distal ureter, lower ileum, colon, and rectosigmoid, it is often difficult to determine if visceral abdomino-pelvic pain is of gynecologic, urologic, or intestinal origin. For these reasons it is important to have the patient complete a pain map.
Women with CPP are more likely to have dysmenorrhea and dyspareunia. For example, dysmenorrhea is present in more than 80 % of women with chronic pelvic pain (in contrast to about 50 % in the general population), and dyspareunia is present in at least 40 % (in comparison to 10–15 % in the general population) [8]. The presence of either of these symptoms often is assumed to indicate a gynecological diagnosis, but dyspareunia and increased pain perimensturally are as common with IBS, IC/PBS, and pelvic floor muscle pain as with gynecological disorders.
Exploring the nature of the onset of pain may aid in diagnosis. For example, an immediately antecedent trauma, such as a fall, surgery, or motor vehicle accident, suggests a musculoskeletal cause. Pain that started with a pregnancy or immediately postpartum may suggest peripartum pelvic pain syndrome. Pain that started at or soon after menarche as dysmenorrhea, progressed to premenstrual pain, and then became constant suggests endometriosis or adenomyosis. If pain started soon after a physical or sexual assault, it may have significant musculoskeletal or psychological components.
Elucidation of any temporal pattern to the pain may be helpful. Cyclicity related to menses suggests gynecologic pain, but is not pathognomonic of gynecologic disease. The same pattern may occur with pain of intestinal, urologic, or musculoskeletal origin also. For example, symptoms of IBS or IC/PBS frequently increase premenstrually. A history of pain or increased pain with coitus is frequently present, as just discussed, and may be due to a variety of disorders, including psychological disease, marital problems, endometriosis, vulvodynia, IC/PBS, and IBS. If intercourse is painful, it is important to find out if pain is with entry at the outermost part of the vagina or if it is with deeper penetration high in the vagina or pelvis, or both. Diseases associated with chronic pelvic pain are not generally associated with entry dyspareunia, except as provoked vulvodynia or vaginismus.
The quality or nature of pain should be sought. For example, neuropathic pain is often described as burning or sharp and piercing, with an electric shock-like quality. Muscular pain may be aching in quality, with sharp, lancing pain with changes in position. Similar qualities of aching with occasional intermittent sharp and radiating pains may also be described with visceral pain. Pain with endometriosis is usually described as cramping [10].
Finding out about any prior treatments for chronic pelvic pain and the response to those treatments is a crucial part of the history. It may be important to know about any prior surgery, not just surgical treatment for pain, because postoperative surgical pain may be a risk factor for or proximate cause of chronic pelvic pain.
Ideally a thorough psychosocial history should be obtained on every patient with chronic pelvic pain. An extensive evaluation by a psychologist or similarly educated professional cannot always be done—nor is it always necessary. However, a basic psychosocial history is always important, especially asking about catastrophizing, anxiety, and depression. Depression, in particular, is one of several predictors of pain severity in women with chronic pelvic pain, and it is also a significant indicator of responsiveness to treatment. Asking about abuse, which may be difficult, is nevertheless another important part of the psychosocial history [11, 12]. Although there is a significant association between physical and sexual abuse and the development of chronic pelvic pain, the presence of moderate or severe depression or history of abuse was not found to be associated with a decreased response to treatment [13].
The physical examination should seek to find the exact anatomic locations of any areas of tenderness and, as much as possible, correlate these with areas of pain. This type of “pain mapping” examination requires a systematic and methodical attempt to duplicate the patient’s pain by palpation, positioning, or bodily movement. At any tender areas or painful positions, the patient should be asked whether the pain produced is the same as her chronic pain. The examination should evaluate the musculoskeletal, gastrointestinal, urinary, and neurological systems, not just the reproductive tract. It facilitates the examination to divide it into standing, sitting, supine, and lithotomy components. As the pelvic examination is particularly relevant for gynecologic disorders, it is the only component of the examination that will be reviewed in detail in this chapter.
Vulvar examination starts with careful visualization of the vulva, perineal body, and anus looking for abnormal pigmentation or erythema, masses, and any skin or mucosal lesions. Palpation should be done with a moistened cotton-tipped swab to evaluate the vulva and the vulvar vestibule for tenderness. This is particularly useful in patients with localized provoked vestibulodynia (vulvar vestibulitis), who have exquisite tenderness in localized areas at the minor vestibular glands just external to the hymen, with normal sensation in adjacent vulvar areas.
A single-digit examination, using only one hand, is how the pelvic examination should be initiated. The introital bulbo-carvenosus and transverse perineal muscles, then the levator ani muscles, should be palpated for tone, spasm, and tenderness. In patients with pelvic floor pain this palpation may cause pain consistent with at least part of the patient’s clinical pain symptoms. Pelvic floor pain may also result from trigger points of one or more of the muscles of the pelvis. The piriformis, coccygeal, and internal obturator muscles should be thoroughly evaluated using single-digit examination. The piriformis muscles can be difficult to evaluate transvaginally, however. Rectal examination may allow an easier evaluation than vaginal examination. Transvaginally or transrectally the examining finger is pressed posterolaterally just superior to the ischial spine. In the lithotomy position, if the patient is asked to abduct the thigh against resistance as the piriform muscle is palpated, the muscle may be more easily palpated, and there is exquisite tenderness of the muscle if there is spasm or tension myalgia involving the piriform muscle (piriformis syndrome).
The anterior vaginal, urethral, and trigonal areas should be palpated to elicit any areas of tenderness, induration, discharge, or thickening suggestive of chronic urethritis, chronic urethral syndrome, urethral diverticulum, vaginal wall cyst, trigonitis, or interstitial cystitis. With deeper palpation the cervix, paracervical areas, and vaginal fornices should be palpated with the single digit for tenderness or trigger points suggestive of problems such as repeated cervical trauma (usually from intercourse), pelvic infection, endometriosis, ureteral pain, or trigger points.
The uterus usually can be adequately evaluated for tenderness by direct palpation with a single digit. Significant uterine tenderness may be consistent with diseases such as adenomyosis, pelvic congestion syndrome, pelvic infection sequelae, endometriosis, or premenstrual syndrome. A uterus that is immobile and fixed in position, especially a retroflexed one, may suggest endometriosis or adhesions. The coccyx can be palpated with the single digit, and an attempt should be made to move it 30° or less. This may be easier to evaluate during the rectovaginal examination. Normally the coccyx moves 30° without eliciting pain, but in patients with coccygodynia this movement elicits pain. The ureteral and the adnexal areas should be palpated next, still using a single digit without the use of the abdominal hand. All of the preceding evaluations are “monomanual-monodigital”—that is, only one finger of one hand is used. No abdominal palpation with the other hand is involved.
The traditional visual, speculum, and bimanual examinations are still needed for a thorough evaluation, but they should usually follow the single-digit examination. A cotton-tipped swab can be used to evaluate the cervical os and the paracervical and cervical tissues for tenderness. In posthysterectomy patients the full vaginal cuff should be similarly palpated for tenderness with a cotton-tipped swab. Any pain or tenderness elicited with the bimanual examination is less specific, because it involves stimulation of all layers of the abdominal wall, the parietal peritoneum, and the palpated organ or organs. Including the rectovaginal examination is important in most women with chronic pelvic pain, looking particularly for nodularity and tenderness.
Endometriosis
Endometriosis is often blamed as the source for CPP but several studies on CPP patients found that the most frequent disorders were in fact non-gynecologic [8, 13] and one found that only 15 % of patients had confirmed endometriosis [13]. Endometriosis is the presence of ectopic endometrial glands and stroma, that is, endometrium located outside of the endometrial cavity. Endometriosis may be found in many locations in the body, but most often is found in the pelvis. Endometriosis remains an enigmatic disorder in that the etiology, the natural history, and the precise mechanisms by which it may cause pain are not completely understood.
Endometriosis has a well-recognized direct association with dysmenorrhea, dyspareunia, and chronic pelvic pain, but it may also be a risk factor for the development of non-reproductive tract CPP. For example, women with dysmenorrhea or endometriosis have increased episodes and increased severity of pain related to urinary calculi than women without dysmenorrhea or endometriosis [14]. Similar results have been experimentally demonstrated for vaginal pain, as well [15]. Also, women with endometriosis have been shown to have an increased incidence of interstitial cystitis/bladder pain syndrome [10, 16]. Such viscero–visceral interactions may have a significant role in chronic pelvic pain in women, reflecting central sensitization, explaining in part why some women with a past history of endometriosis have persistent pelvic pain after their endometriosis is gone [17].
Neither the etiology of endometriosis nor the etiology of pain associated with endometriosis is completely understood. The etiology of endometriosis is complex, but it seems certain that both genetic and environmental factors contribute to the disease phenotype. There are several general theories regarding the etiology of endometriosis but none is sufficient to explain the protean manifestations of endometriosis, or the predilection of some women, but not others, to develop symptomatic endometriosis. For example, the most widely spread theory, retrograde menstruation occurs in most women but only 5–10 % develop endometriosis [18].
Endometriosis is a disease of women of reproductive age, so most women with endometriosis-associated pain are 20–45 years of age. However it has been reported in girls as young as 10 years and it may be a more common cause of pain in teenagers than is generally recognized. It may also occur in postmenopausal women, particularly if they are on estrogen replacement.
Classically the woman with endometriosis presents with one or more of the following triad: an adnexal mass (endometrioma), infertility, or pelvic pain [19]. Pelvic pain most often starts as dysmenorrhea and about 90 % of women with endometriosis-associated pelvic pain have dysmenorrhea as a component of their pain symptoms. Perimenstrual exacerbation of pain can also occur in women with IC/PBS and IBS, and menstrual suppression may reduce these pain flares. Also, these three common diagnoses frequently occur together. One study found only 18 % of women with endometriosis had only endometriosis, while 32 % also had IC/PBS and 31 % had IBS [10]. Dyspareunia with deep penetration is also a frequent component of endometriosis-associated pain, occurring in about 40 % of cases. Intestinal involvement occurs in about 15 % of women with endometriosis and may be associated with gastrointestinal symptoms of tenesmus, dyschezia, constipation, diarrhea, low back pain, and, rarely, hematochezia or symptoms of bowel obstruction. Urinary tract involvement occurs in about 10 % of women with endometriosis and may be associated with urinary frequency, pressure, dysuria, or hematuria.
In many women with endometriosis-associated pelvic pain the physical examination is completely normal. In others there is tenderness and other findings only during menses. For this reason it is sometimes helpful to do the examination during the first day or two of menstrual flow in women with suspected endometriosis. Some women with endometriosis have persistent areas of tenderness in the pelvis, whether or not they are menstruating. Classic physical findings include a fixed retroverted uterus with tenderness posteriorly, tender nodularity of the uterosacral ligaments, and cul-de-sac on rectovaginal examination. However, these are not commonly found. Asymmetrically enlarged, tender ovaries that are fixed to the broad ligaments or pelvic sidewalls may also occasionally be found.
The symptoms and signs that lead to a clinical diagnosis of endometriosis are reliable 65–80 % of the time, but an accurate diagnosis can only be made by surgical excision with histologic confirmation [20, 21]. Accurate diagnosis requires microscopic visualization of both endometrial glands and stroma [22, 23]. As endometriosis may have a wide variety of gross appearances, it is essential that the surgeon be familiar with the variety of potential appearances of endometriosis for accurate diagnosis [22, 23]. A negative laparoscopy should lead one to consider other diagnoses such as IC/PBS or IBS, which can mimic endometriosis.
Treatment of endometriosis is also complex and many factors must be considered in planning treatment. It is important to educate the patient about endometriosis and the treatment options and actively involve her in decision-making. The patient’s age, reproductive plans, duration of infertility, and attitude toward surgery or toward hormonal medications may be vital components of the patient’s needs or concerns.
There are many medical treatments available for endometriosis-associated pelvic pain. Only those used commonly with good evidence of efficacy will be reviewed here.
Medical treatment with gonadotropin releasing hormone (GnRH) agonists, progestins, danazol or combined oral contraceptives effectively relieves endometriosis-associated pelvic pain. The number needed to treat for medical treatments is 2–2.5 [24].
GnRH agonists shut down LH and FSH production and release, leading to a dramatic decline in estradiol levels, induction of amenorrhea, and improvement of pain levels. When patients have a recurrence of pain within 1 year after treatment with GnRH analogs, re-treatment appears to be reasonably effective, with about two-thirds of patients showing a significant reduction of pain levels during re-treatment [25]. Loss of bone density with GnRH analogs is a serious concern. Clinical trials with GnRH agonists show that add-back therapy with conjugated equine estrogen and/or norethindrone acetate significantly decreases bone loss [26].
Danazol, a 17-ethinyl-testosterone derivative, has efficacy similar to that of GnRH agonists, but is not as frequently used due to possible androgenic side effects, including significant weight gain, mood changes, and masculinizing symptoms [27].
Medroxyprogesterone acetate (MPA) has been a recommended treatment for many years. Although a high dose of 100 mg/day was used in the only placebo-controlled trial of MPA, lower doses are used generally in clinical practice [28]. A randomized study of a 104 mg dose of a subcutaneous formulation of MPA compared to depot-leuprolide showed similar efficacies for both treatments [29].
Oral contraceptive (OCP) treatment of endometriosis is a long-standing approach, using either cyclical or continuous dosing. Efficacy appears to be similar or somewhat less than the other hormonal treatments [30]. There is some evidence that women not responsive to cyclical administration of OCPs may respond to continuous administration [31].
Some more recent approaches to medical treatment of endometriosis-associated pelvic pain are levonorgestrel-releasing intrauterine device [32], aromatase inhibitors [33, 34], selective progesterone modulators [35], and other progestins [36]. Although data from randomized clinical trials are needed, current evidence suggests that these therapies are effective alternatives in many patients.
Surgical treatment can be done at the time of laparoscopic diagnosis in symptomatic women. Organ-preserving, laparoscopic surgical treatment has been shown to significantly improve pain in women with stage II, III, and IV endometriosis, with a number needed to treat of 2–2.5 [37, 38]. Surgery for advanced-stage endometriosis can be challenging, tedious, frustrating, and prone to complications, so it is likely that surgical outcomes are surgeon dependent. Postoperative medical treatment may improve pain relief for the duration of the medical treatment, but does not improve long-term outcomes [28, 39, 40].
Presacral neurectomy (resection of the superior hypogastric plexus) and uterosacral neurectomy (uterine nerve resection or transection of the uterosacral ligament) have been recommended for relief of CPP associated with endometriosis. Data from clinical trials show that presacral neurectomy somewhat improves pain relief obtained with surgical treatment of endometriosis [41, 42]. However, presacral neurectomy may lead to intractable constipation and urinary urgency in up to 5 % of patients [43]. Data from clinical trials show that uterosacral neurectomy does not improve pain relief when included in surgical treatment of endometriosis and should not be performed [44].
If fertility is not desired, then hysterectomy, with or without bilateral salpingo-oophorectomy, is often recommended for endometriosis-associated pelvic pain. There is no consensus as to the advisability of removal of both ovaries if one or both are not directly involved by endometriosis. In one study evaluating this dilemma, recurrence of pain when one or both ovaries are preserved has been reported to occur in 62 % of cases compared to 10 % when both ovaries are removed, giving a relative risk for pain recurrence of 6.1 (confidence interval 2.5–14.6) [45]. Reoperation for pain was also more likely with ovarian preservation, with 31 % requiring reoperation compared to 4 % if both ovaries were removed at the time of hysterectomy for endometriosis. Although uncommon, endometriosis has been reported to recur after hysterectomy and bilateral salpingo-oophorectomy, with and without estrogen replacement therapy [46–48]. The potential risks of cardiovascular and bone density risks in premenopausal women without estrogen replacement likely outweigh the rare risk of recurrence.
Complications of medical treatment include side effects of weight gain, edema, hot flushes, headaches, nausea, acne, hirsutism, hot flushes, abnormal uterine bleeding, decreased breast size, decreased libido, vaginal dryness, weakness, decreased bone density, and thromboembolic disease. Surgical complications vary with the severity of disease, but injury to pelvic viscera is a potential risk in women with endometriosis. Endometriosis untreated is rarely life threatening, although there are cases of ureteral and bowel obstruction due to endometriosis, as well as invasion of the urinary and gastrointestinal tracts.
It is important to recognize that the finding of endometriosis in women with CPP does not ensure that medical or surgical treatment of endometriosis will result in effective relief of pain. To the contrary, although treatment of endometriosis in women with pelvic pain is clearly indicated based on randomized, placebo-controlled, double-blind clinical trials, pain relief of 6 or more months duration due to treatment can be expected in only about 40–70 % of women with endometriosis-associated CPP (number needed to treat of 2.0–2.5). Also, recurrence rates of CPP are high after medical and surgical therapy. Women with endometriosis need to be evaluated for all sources of chronic abdomino-pelvic pain including non-gynecologic to ensure appropriate treatment for their CPP.
Pelvic Congestion Syndrome
Pelvic Congestion Syndrome (PCS) is defined by the triad of pelvic pain, pelvic varicosities, and abnormal venous function. Abnormal venous function is identified by a pelvic venogram. Pain is usually worse premenstrually rather than having pain levels which peak with menses. Symptoms often develop after childbirth as pregnancy increases the capacity of pelvic veins by 60 % [49]. Both of these are likely related to hormonal changes affecting the pelvic vasculature associated with pregnancy and the menstrual cycle. In addition, pain is usually dull and aching, with exacerbations related to movement and position changes such as sitting to standing, or left to right side while supine, and may improve after lying down. Backaches which worsen with standing can also occur. Deep dyspareunia and post-coital pain are very common. On abdominal exam, palpation at the ovarian point can reproduce the pelvic pain in 80 % of women with PCS. This point lies at the junction of the upper and middle thirds of a line drawn from the anterior superior iliac spine to the pubic symphysis. Adnexal tenderness may also be found on bimanual exam.
Diagnosis is confirmed by a pelvic venogram showing venous stasis, dilation, delayed emptying and a plexus formation of the ovarian or uterine vessels. This can be performed by transcervical injection of the myometrium at the fundus or by transcutaneous retrograde injection of the ovarian veins by interventional radiology with serial imaging. It cannot be diagnosed on ultrasound or CAT scan or by simply visualizing enlarged pelvic vessels on laparoscopy.
Treatment can be either menstrual suppression with progestin hormonal therapy, with GnRH agonists, with embolization of the dilated ovarian vessels by interventional radiology, or for refractory cases in women done with child-bearing, hysterectomy and bilateral salpingo-oophorectomy. Symptom improvement after embolization may take several months, but long-term success in a small 3-year follow up study has been reported at 76 % [50].