What is pelvic inflammatory disease?

Female friends may suffer from various diseases in their lives, and pelvic inflammatory disease is one of them. Many people are worried that pelvic inflammatory disease will cause excessive harm to the health of female patients. We all know that pelvic inflammatory disease is indeed difficult to treat, so we need to understand what this disease is. We must seriously figure out what is going on.

1. Concept

1. Definition

Pelvic inflammatory disease (PID) is the most common and most serious infectious disease in women, and its incidence has increased significantly in recent years. The U.S. Centers for Disease Control and Prevention (CDC) defines it as a group of diseases caused by infections of the female upper reproductive tract, mainly including endometritis, salpingitis, tubo-ovarian abscess and pelvic peritonitis. PID can be confined to one site or involve several sites at the same time, the most common of which is salpingitis. PID mostly occurs in sexually active, menstruating women, but rarely occurs in premenarche, postmenopausal or unmarried women. If pelvic inflammatory disease occurs, it is often the spread of inflammation in adjacent organs.

2. Domestic understanding of pelvic inflammatory disease

In the past, the "Obstetrics and Gynecology" textbook divided pelvic inflammatory disease into acute pelvic inflammatory disease and chronic pelvic inflammatory disease. Domestic textbooks describe the symptoms of acute pelvic inflammatory disease as lower abdominal pain accompanied by fever and increased vaginal discharge at the onset of the disease; physical examination shows lower abdominal tenderness or rebound pain and muscle tension; cervical lifting pain, uterine body tenderness, and adnexal tenderness. The description of chronic pelvic inflammatory disease is that the systemic inflammatory symptoms are not obvious, sometimes only low fever, fatigue, lower abdominal distension, pain and lumbar pain; cord-like thickening of the fallopian tube or lamellar thickening and tenderness can be felt on one or both sides of the uterus. The pelvic inflammatory disease in the 7th edition of the textbook "Obstetrics and Gynecology" mainly refers to acute pelvic inflammatory disease, and chronic pelvic inflammatory disease is no longer discussed.

3. Foreign knowledge on pelvic inflammatory disease

By definition, pelvic inflammatory disease is an acute inflammatory process, and the concept of chronic pelvic inflammatory disease is usually inappropriate, so chronic pelvic inflammatory disease refers to the sequelae of the acute process, that is, the sequelae of pelvic inflammatory disease (sequelae of PID). The clinical manifestations of pelvic inflammatory disease are wide-ranging, ranging from mild to severe patients with obvious clinical symptoms, to patients with "asymptomatic" or "atypical" pelvic inflammatory disease. Wolner-Hanssen proposed the concept of “asymptomatic”, “atypical” and “latent” pelvic inflammatory disease [1]. This type of pelvic inflammatory disease is not asymptomatic or subclinical infection, but these women are unaware of their own symptoms[2] and therefore do not seek medical treatment or are not diagnosed with pelvic inflammatory disease.

(IV) Recurrent PID

Recurrent PID is currently classified as a sequela of PID. Based on some foreign literature reports and clinical observations, I believe that recurrent pelvic inflammatory disease also falls into the category of PID and should not be classified as a sequela of PID. This is because women who have had PID may have another episode of pelvic inflammatory disease, and the results of bacterial culture of the lesions show that it is actually a second pelvic infection. In addition, women with PID caused by STDs are very likely to be exposed to these microorganisms again after clinical treatment, thus being reinfected and causing PID. In addition, delayed treatment and non-standard treatment can cause latent infection of microorganisms in the lesions, forming "asymptomatic" PID. Many data show that recurrent PID is an important cause of PID sequelae.

5. Sequelae of pelvic inflammatory disease

Short-term sequelae of pelvic inflammatory disease include perihepatitis (Filipino-Kerr syndrome), tubo-ovarian abscesses, and rarely death. Long-term sequelae include infertility, ectopic pregnancy, and chronic pelvic pain. The sequelae of PID are related to whether PID can be diagnosed early and effectively treated, to "asymptomatic" or "hidden" PID, and to the number of PID attacks. Foreign literature reports that none of the patients with clinical PID symptoms treated within 2 days of onset developed infertility. It has also been reported that those who were treated 3 days after symptom onset had a higher probability of infertility than those who were treated within 3 days (19.7%: 8.3%).

In summary, the concept and diagnosis of chronic pelvic inflammatory disease are relatively vague. The chronic pelvic inflammatory disease previously diagnosed in China may include atypical or latent PID and recurrent PID, and may also include PID sequelae or both. If the domestic concept of chronic pelvic inflammatory disease continues, it may continue to lead to misdiagnosis and delayed treatment of a large number of PIDs, thus causing the occurrence of PID sequelae.

2. Etiology

PID is caused by pathogenic microorganisms ascending from the lower genital tract to the upper genital tract, occasionally spreading directly through the lymphatic system, blood circulation, or adjacent organs. The microorganisms detected from PID patients can be divided into two major categories: endogenous microorganisms come from the flora residing in the vagina, including aerobic bacteria and anaerobic bacteria. It can be an aerobic infection alone or an anaerobic infection alone. Mixed infection of aerobic and anaerobic bacteria is more common, and about 2/3 of the cases are combined with anaerobic infection; exogenous pathogens include Neisseria gonorrhoeae, Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis, and Mycoplasma genitalium. Neisseria gonorrhoeae and Chlamydia trachomatis are the main sexually transmitted microorganisms that cause PID. The pathogenic role of M. genitalium is still unclear.

3. Risk factors of PID

Risk factors for PID include age, sexual behavior, contraceptive measures, vaginal douching, etc.

(A) Age is inversely proportional to the incidence of PID. Sexually active women under 24 years of age are three times more likely to develop PID than women aged 25-29, but their chances of developing sequelae such as infertility are lower than those in older age groups.

(ii) The high prevalence of sexually transmitted infections (STDs) has led to an increased incidence of PID. Neisseria gonorrhoeae, Chlamydia trachomatis infection and bacterial vaginosis (BV) are important risk factors for PID.

(III) Sexual behavior is associated with an increased risk of PID. Age of first sexual intercourse, frequency of sexual intercourse, multiple sexual partners in a short period of time, and sexual intercourse during menstruation.

(IV) The relationship between the choice of contraceptive method and PID. The risk of PID and its sequelae increases 2-9 times in women with intrauterine contraceptive devices. The WTO reported that women with IUDs have a 2-4 times higher risk of developing acute salpingitis than those who use other contraceptive measures or do not use contraception. Reasonable use of condoms can reduce the risk of STDs, PID, tubal infertility and ectopic pregnancy. Oral contraceptives can reduce the risk of clinically symptomatic PID by 40%-60%. Oral contraceptives change the cervical mucus, hindering the invasion of vaginal and cervical microorganisms into the upper reproductive tract; oral contraceptives shorten the menstrual period and reduce the menstrual flow, shortening the "window period" for microorganisms to invade the uterus and fallopian tubes. Svensson et al. reported that women who took oral contraceptives had a better prognosis for future pregnancy than women who used other methods of contraception.

(V) Vaginal douching increases the risk of PID and ectopic pregnancy. Vaginal douching changes the pH and ecological balance of the normal vaginal flora, leading to the dominance of certain microorganisms or susceptibility to bacterial vaginosis, increasing the risk of PID. Vaginal douching can allow microorganisms to invade the upper reproductive tract, increasing the risk of upper reproductive tract infection.

(vi) Women with PID are most likely to experience symptom onset within 7 days of menstruation. Smoking, alcoholism, and abuse of illicit drugs are associated with the occurrence of PID.

If we can better understand the knowledge of pelvic inflammatory disease, the treatment of this disease will not be a problem. In fact, if we can prevent the occurrence of this disease before it occurs, the disease will not endanger the patient's health. This requires us all to understand the cause of pelvic inflammatory disease.