Endometritis and salpingitis are thought to be components of pelvic inflammatory disease (PID). Some women who have PID without laparoscopic evidence of salpingitis have histologic evidence of endometritis on endometrial biopsy. Eckert and associates conducted a prospective study of women with suspected PID using laparoscopy and endometrial biopsy to identify the differences between women with salpingitis and women with endometritis alone.

The study involved 152 women who had lower abdominal pain for up to three weeks and abnormal adnexal tenderness on pelvic examination. Study subjects were not pregnant and had not recently taken antibiotics. Participants gave a detailed history, which was followed by a gynecologic examination with gonorrhea and Chlamydia cultures, endometrial biopsy, and laparoscopy to confirm PID. Acute salpingitis was defined as the presence of tubal erythema, edema, and exudate on laparoscopy, while endometritis was defined as biopsy findings of plasma cells in the endometrial stroma and neutrophils in the endometrial surface epithelium.

Of the study participants, 43 (28 percent) had neither salpingitis nor endometritis, 26 (17 percent) had endometritis alone, and 83 (55 percent) had salpingitis. Of the women with salpingitis who had endometrial biopsies, 85 percent had histologic evidence of endometritis. The presence of endometritis was not associated with age, frequency of intercourse, recent new or multiple partners, duration of symptoms, douching, oral contraceptive use, or history of PID. A diagnosis of endometritis alone was associated with the use of an intrauterine device (IUD) and recent douching, especially among women infected with Chlamydia, gonorrhea, or bacterial vaginosis. Endometritis was also diagnosed more often during days 1 through 14 of the menstrual cycle.

Women with endometritis alone were more likely to have severe abdominal pain and less likely to have severe lower quadrant tenderness, severe adnexal tenderness, severe cervical motion tenderness, a temperature of at least 38°C (100°F), and peritonitis on laparoscopy. Elevated white blood cell count, erythrocyte sedimentation rate, and C-reactive protein levels were more common in women with salpingitis.

The authors conclude that the physical findings in women with endometritis are generally less pronounced than those in women with salpingitis but are more prominent in the former group than among women who have neither endometritis nor salpingitis.

Positive cultures for gonorrhea or Chlamydia are more common among women with endometritis than among women with salpingitis alone. Recent douching and days 1 through 7 of the menstrual cycle increase the risk of endometritis among women with or without cervical or vaginal infection, and IUD use is a risk factor among women without clear infection. The natural history of endometritis, which can be either symptomatic or asymptomatic, and the frequency with which endometritis may clear with menses, persist in a limited manner, or progress to salpingitis, needs further study.