Chronic pelvic inflammatory disease is one of the common diseases seen in gynecology clinics, and chronic pelvic pain is one of the most common reasons for their visits. Chronic pelvic pain is defined as non-cyclical pelvic pain that lasts more than six months. The common gynecological diseases causing chronic pelvic pain include endometriosis, pelvic adhesions, and pelvic stasis syndrome, in addition to chronic pelvic inflammatory disease. Common non-gynecological diseases include irritable bowel syndrome, urinary system diseases, musculoskeletal abnormalities and psychological factors. This article analyzes and compares chronic pelvic pain caused by chronic pelvic inflammatory pain with chronic pelvic pain caused by other diseases.
1, chronic pelvic inflammatory disease
The inflammatory diseases that occur in the female internal genitalia and its surrounding connective tissue and pelvic peritoneum are called pelvic inflammatory disease, including uterine inflammation, tubo-ovarian inflammation, pelvic connective tissue inflammation and pelvic peritonitis. Chronic pelvic inflammatory disease is caused by the untimely or incomplete treatment of acute pelvic inflammatory disease, and the long-term inflammatory stimulation results in various types of disease.
1.1 Chronic endometritis
Due to the periodic exfoliation of the endometrium and the good drainage conditions of the uterine cavity, inflammation rarely has a chance to stay in the endometrium for a long time, and clinically, except for tuberculous and senile endometritis, other lesions are rare. It is mainly seen in cases of intrauterine device placement, placenta-fetal membrane residual mechanization after abortion or delivery, submucosal fibroids or mucosal polyps in the uterus with infection, and upstream infection of pathogenic bacteria in the vagina. About 40% of patients with chronic endometritis complain of lower abdominal cramping pain and lumbosacral ache during intermenstrual periods [1]. This is accompanied by increased leucorrhea, excessive menstruation and dysmenorrhea. The main signs were: normal or slightly large uterus size with tenderness and no significant abnormalities in the bilateral adnexal areas. The diagnosis of chronic endometritis pain is not difficult, and ultrasound and hysteroscopy are feasible if necessary to understand the intrauterine situation.
1.2 Chronic tubo-ovarian inflammation
It is the most common type of chronic pelvic inflammatory disease and one of the most common causes of chronic pelvic pain. The types of lesions can be subdivided into 4 types: chronic interstitial tubal inflammation, adnexitis masses, tubal effusion and tubo-ovarian cysts, tubal pus and tubo-ovarian abscesses. Because of the close proximity of the fallopian tubes and ovaries and the abundance of blood vessels and lymphatic vessels, chronic tubal and ovarian inflammation often coexist. The pain is characterized by vague and swelling pain in the lower abdomen, often heavier on one side, and soreness in the lower back and sacral area, which is aggravated after exertion. Due to pelvic adhesions, there may be painful filling of the bladder and rectum or painful emptying. It is accompanied by excessive and frequent menstruation, dysmenorrhea, infertility, increased leucorrhea and painful intercourse. Long-term pelvic pain can also lead to gastrointestinal dysfunction, fatigue, depression and other systemic symptoms. Signs: The uterus is often posteriorly positioned, with poor activity. There is usually pain when moving the cervix or uterine body, and in mild cases, only one or both sides of the adnexal area can be palpated with striated thickening, while in severe cases, fixed masses of varying sizes and irregularities can be palpated on both sides of the pelvis or the posterior side of the uterus, mostly with pressure pain. If the wall is thin, tense and slightly movable, it is more likely to be hydronephrosis; thick-walled and adherent cysts are more likely to be abscesses. Ultrasound and laparoscopy can be performed to assist in the diagnosis.
1.3 Chronic pelvic connective tissue infection
Pelvic connective tissue is fibrous connective tissue located in the posterior pelvic peritoneum, on both sides of the uterus and in the anterior bladder space. The cervical and uterine lymph are directly connected to the parametrial tissues, so inflammation can spread to the parametrium via lymphatic spread due to cervical injury, hematoma and infection around the vaginal dissection after total hysterectomy, and damage to the uterine wall during uterine operations. In addition, severe chronic cervicitis can also cause chronic pelvic connective tissue inflammation. Pain features: lumbosacral cramping and lower abdominal distension, painful intercourse is a common symptom due to the low location of the lesion. The main signs: the uterus is normal in size, often posteriorly positioned or displaced, with restricted movement. Bilateral thickening of the uterosacral ligaments, such as two cords encircling the sides of the rectum, with tenderness, and bilateral thickening of the parametrial tissues, usually more pronounced on one side, are often found during the triage examination. If the uterus is fixed or enclosed in the surrounding inflammatory scarring tissue, it is frozen, called “frozen pelvis”, which is now rare clinically due to the early treatment of inflammation and the application of broad-spectrum antibiotics.
2.Differential diagnosis
In addition to chronic pelvic pain caused by pelvic inflammatory disease, there are many other diseases that can cause chronic pelvic pain, which are described below for differentiation.
2.1 Endometriosis
During diagnostic laparoscopy of women with chronic pelvic pain, it was found that 10% to 50% were patients with endometriosis [2]. In severe pelvic lesions, this often leads to pelvic adhesions and pelvic congestion, resulting in lower abdominal pain and lumbosacral cramping even between menstrual periods, which is aggravated before and during menstruation, and is easily confused with chronic pelvic inflammatory pelvic pain. However, the typical symptoms of endometriosis are secondary, progressive dysmenorrhea accompanied by painful intercourse, infertility, menstrual disorders, and bowel or urinary tract symptoms. The site of pain is related to the location of the lesion. For example, lesions involving the rectal uterine sulcus, the uterosacral ligament or the vaginal rectal septum often cause pain in the lumbosacral region and radiate to the anus, resulting in painful intercourse; lesions involving the rectum and sigmoid colon may cause difficulty in defecation or painful cramping, or even blood in the stool; lesions invading the bladder may cause periodic urinary frequency, painful urination and hematuria; ectopic lesions in the abdominal wall scar cause pain in the abdominal wall scar during menstruation. The typical signs of endometriosis are one or several hard nodules with pressure pain, often found in the posterior superior aspect of the cervix or in the uterosacral ligament. The uterus is often fixed posteriorly and is normal or enlarged in size. If the lesion involves the ovaries, a cystic mass with thick, often fixed walls may be found on one or both sides of the uterus and may be painful. However, in some patients with endometriosis, the symptoms and signs are not obvious and it is difficult to differentiate them from chronic pelvic inflammatory disease, so diagnostic treatment or laparoscopy can be tried to clarify the diagnosis.
2.2 Pelvic adhesions
It is most often caused by pelvic surgical infection or foreign body reaction, and is most commonly caused by surgical trauma. According to Frankfurter, 79% of patients with pelvic adhesions have a history of previous surgery, especially gynecological and appendectomy. The most common sites of adhesions after gynecologic surgery are the greater omentum and small intestine, and colonic adhesions are rare. The ileum is the most common site of small bowel adhesions, and because part of the ileum is located in the pelvis, it is prone to pelvic adhesions, especially in short and fat women.
The most common symptom of pelvic adhesions is pelvic pain, which is easily confused with chronic pelvic inflammatory disease. Monk reported that 20% to 50% of people with chronic pelvic pain suffer from this condition, which is mainly associated with entrapment pain and visceral pain due to tissue ischemia or altered tone caused by fibrosis, which irritates the organs. The pain is characterized as non-cyclic, with a chronic persistent dull pain that can lead to secondary dysmenorrhea [3]. Pelvic adhesions can alter the pelvic anatomy, affecting the peristalsis of the fallopian tubes or causing their obstruction and causing infertility. Laparoscopy is the best option to diagnose this condition.
2.3 Pelvic stasis syndrome
This refers to a syndrome of chronic lower abdominal pain, postcoital pain, low back pain, extreme fatigue, and vegetative dysfunction due to varicose veins or venous plexus and stasis of blood. It is mostly seen in women of childbearing age who have given birth, and the symptoms most often start within a short period of time after a particular delivery or miscarriage, and is also an important cause of chronic pelvic pain.
The symptoms of pelvic stasis syndrome are widespread and do not have very typical signs, resulting in a frequent discrepancy between the patient’s conscious symptoms and the objective examination. The most common symptom is lower abdominal pain, mostly chronic diffuse or bilateral lower abdominal pain in the suprapubic symphysis, with persistent cramping, often heavier on one side, starting in the middle of menstruation and aggravated by prolonged standing, fatigue, supine sleep, after sexual intercourse and a few days before menstruation. Most patients have congestive dysmenorrhea, which mostly starts before menstruation. It may be accompanied by excessive leucorrhea, a saucy color of menstrual blood and breast tenderness due to cyclic edema of the breast. More than half of the patients have phytodysfunction, such as irritability, agitation, insomnia, dreaminess, headache, palpitation and poor appetite. The physical signs on gynecological examination are mostly inconspicuous and not proportional to the severity of subjective symptoms. Vulvar and vaginal varices may be found; cervical hypertrophy and petechial hemorrhage with purple-blue color; uterus is mostly posterior, soft and full; pain increases when touching the cervix or posterior vault, without obvious painful knots, or obvious abdominal muscle tension and rebound pain. It is easily misdiagnosed as chronic pelvic inflammatory disease. Pelvic venography is the main method to confirm the diagnosis of this disease, and laparoscopy helps in the diagnosis and differential diagnosis.
2.4 Irritable bowel syndrome
The incidence is higher in women than in men, about 3:1. According to Kay, 7%-60% of patients with chronic pelvic pain are caused by this syndrome, and the cause of abdominal pain is unknown, probably due to abnormal and strong contraction of intestinal smooth muscle. Its pain characteristics: abdominal pain is diffuse, no fixed pain point, may be paroxysmal or continuous spasmodic pain, mostly in the left lower abdomen, with increased pain after stress, depression, eating and premenstrual or menstrual periods, mostly accompanied by chronic constipation, occasionally diarrhea, a few patients have painful intercourse similar to gynecological disease. The gynecologic triad can often have pressure pain in the sigmoid area without other signs of inflammatory bowel disease. Abdominal ultrasonography can be used to understand the presence of occupying lesions, and sigmoidoscopy can assist in the diagnosis.
2.5 Musculoskeletal abnormalities
Musculoskeletal abnormalities are also a common cause of chronic pelvic pain, but they are often underappreciated by clinicians and thus are often missed. Since the pelvic floor muscles, ligaments, and reproductive organs in the pelvis have the same innervation as the lumbar spine, the area below the iliac joint, and the trunk muscles, either reproductive organ disease or musculoskeletal malfunction can cause similar pelvic pain and low back pain. The difference between the two causes of pain is that the degree and location of musculoskeletal pain often changes with position change or after activity, and the pain decreases significantly after rest and increases when the affected muscle is exerted. There are no abnormal findings on gynecological examination of the pelvis. In the case of anal raphe spasm, the patient complains of a sensation of falling, which is evident in the afternoon and evening, often accompanied by back and lumbosacral pain, which increases during the premenstrual period, but is less cyclical than endometriosis and pelvic stasis syndrome, and the pain can be relieved when the patient is in a recumbent position. The main sign is anal raphe tenderness, and the pain increases when the patient is instructed to contract the anal raphe; this test is an effective way to confirm the diagnosis of this disease [4].
2.6 Urological disorders
Urological diseases such as urethral syndrome, recurrent cystourethritis and interstitial cystitis can cause chronic pelvic pain, but because patients usually have bladder irritation symptoms such as urinary frequency, urinary urgency and pain, they are easily distinguished from pelvic pain caused by chronic pelvic inflammatory disease.
2.7 Psychological factors
According to domestic reports, the etiology of chronic pelvic pain is due to social factors accounting for 5%-25%. Psychogenic pelvic pain has the following characteristics: persistent dull pain, often painful upon awakening, and can be attacked both in the presence of psychosocial factors; inconsistent with the distribution of nerves, non-radioactive, diffuse pain sites, and easy to change; maintaining the same pain for a long time, without improvement or intensification; not triggering or increasing pain during gynecological examination. It is commonly seen in patients with depression, dysthymia and delusional psychiatric disorders [5].
In conclusion, there are many diseases that cause chronic pelvic pain, and the diagnosis should not be limited to chronic pelvic inflammatory disease in clinical work, using ultrasound, hysteroscopy and laparoscopy to assist in the diagnosis, and in patients in whom it is difficult to find any organic lesion, several more causative factors should be considered to facilitate a clear diagnosis.