Pelvic inflammatory disease occurs when bacteria move upward from the woman’s vagina or cervix into the reproductive or other organs and can cause PID, but many cases are associated with gonorrhea and chlamydia, two very common bacterial STDs. A prior episode of PID increases the risk of another episode because the reproductive organs may be damaged during the initial bout of infection. Females below the age of 25 are especially at risk, because the cervix of teenage girls and young women is not fully matured, with the squamocolumnar zone on the ectocervix, increasing their sensitivity to STDs and PID.

One out of seven, approximately 14%, of all women will get salpingitis in their lifetime. Pelvic soft tissue infection is more common in blacks than whites. Divorced women are more likely to get salpingitis than currently married women or never married women (19%, 12%, and 6%, respectively). The risk of salpingitis increases with the number of lifetime sexual partners (7% in women with one lifetime partner vs 19% in women with two or more). Other associated risk factors include increased number of sexual partners, people who have sex partners who themselves have more than one sex partner, women who douche frequently, and a slight increased risk at the time of insertion of an intrauterine device (IUD).

Historic information directly correlated with the etiology of a sexually transmitted disease (STD) includes: the time of onset of symptoms relative to the onset of the last menstrual period (LMP), last sexual exposure, number of sexual partners (lifetime but, perhaps more importantly, over the last 2–3 months), history of previous STD (whether treated as an outpatient or as an inpatient), sexual partner with symptoms (complaint of urethral discharge or “drip”), and contraceptive practices. A history of recent instrumentation may elucidate the mechanism by which endogenous flora may gain access to and produce disease of the upper genital tract and includes the following: dilation and curettage (D&C) for diagnosis or elective termination of pregnancy, intrauterine contraceptive device insertion, or hysterosalpinography. Smoking predisposes the patient to more STDs, possibly because smokers are greater risk takers and are more sexually active than nonsmokers and probably because smoking alters the host defense by reducing biologically active estrogens, impairing ciliary activity of oviductal cells, reducing leukocyte action, and reducing immunoglobulin A activity in cervical mucus.

Many signs and symptoms may suggest infection of the pelvic structures. A patient may complain of fever, abdominal or pelvic pain, cervical or vaginal discharge, nausea, vomiting, right upper quadrant pain, etc. Upon examination, she may be found to have a normal temperature or temperature elevation; localized or generalized pain or tenderness with or without evidence of pelvic or abdominal peritonitis; discharge, the source, character and amount of which may be suggestive of the offending pathogen(s), etc. These may be characterized by the presence of “-ors,” the classic findings associated with inflammation: color (heat), dolor (pain), rubor (redness), and tumor (mass). Additional findings may be characterized by utilizing the suffixes “-osis,” the presence of organisms without histologic changes induced in underlying tissues (e.g. nonspecific vaginosis), and “-itis,” the presence of pathogenic organisms with histologic changes induced in the underlying tissues (e.g. vaginitis, endometritis, salpingitis); or abscess, a collection of pus and debris composed of desquamated or necrotic cells, tissues or organisms contained in a circumscribed location (e.g. appendiceal abscess, demarcated by loops of bowel), or by the destruction of organs or tissues (e.g. tubo-ovarian abscess).

In 2006 the CDC set forth the following criteria for diagnosis of PID. The patient must have a minimum of one of the following: lower abdominal pain, adnexal tenderness, and tenderness with cervical motion, and also one or more of the following additional criteria: sign of lower genital tract inflammation, oral temperature more than 101º F, abnormal cervical or vaginal discharge, greatly increased number of white blood cells on saline microscopy of vaginal secretion, elevated erythrocyte sedimentation rate, elevated C-reactive protein levels, laboratory documentation of cervical infection with C. trachomatis or N. gonorrhoeae. Additional findings may be present, including: histologic evidence of endometritis at endometrial biopsy, pelvic fluid or tubo-ovarian complex on transvaginal sonogram or images from other modalities, and laparoscopic abnormalities that are consistent with PID, including presence of pus seen exuded through the tube.

Various simple tests may be performed in order to suggest the identity of the pathogenic organisms. A wet-mount smear with sodium chloride may aid in the diagnosis of nonspecific bacterial vaginosis, nonspecific vaginitis or Trichomonas vaginalis, while one utilizing potassium hydroxide aids in the diagnosis of Candida albicans. Gram stains made of cervical discharge, vaginal discharge, wound infections or from margins of abscesses permit the identification of broad classes of organisms based on their morphologic appearance and gram stain status. Empiric therapy may be selected, accordingly, while results of cultures are pending. These cultures should be obtained from portals or adjacent structures involved in sexual activities. These may include the oropharynx, urethra, cervix, vagina, and rectum. It may be necessary to obtain cultures for aerobic and anerobic organisms, GC, and genital mycoplasmas, as well as tissue cultures for CT. More recently, the availability of ligase chain reaction and polymerase chain reaction has made the screening for GC and CT from cervical or urine specimens more efficient and cost-effective. New tests have emerged that can do screening for both gonorrhea and chlamydia in one culture, which has made the screening process much easier.

Ultrasound of the female pelvis is frequently performed but it has not replaced the pelvic examination. If adnexal masses are visualized by ultrasound, suggesting inflammatory processes, the prudent physician does not aspirate them; instead, a trial of antibiotic therapy is instituted. An x-ray of the abdomen and pelvis may demonstrate gas in soft tissues; air under the diaphragm, suggestive of a perforated viscus; a mass lesion; ileus, etc. A CT or MRI scan may identify masses or a blood-filled collection that are not discernible by other diagnostic studies. A barium enema (BE), upper gastrointestinal tract series (UGI) or intravenous pyelography may be useful in establishing or ruling out the diagnosis of gastrointestinal or genitourinary conditions. Thus, standard diagnostic tests are useful in making the diagnosis of female pelvic soft tissue infections.