Pelvic inflammatory disease is an infection and inflammation of a woman's fallopian tubes (salpingitis) and uterine lining (endometritis), which can lead to pelvic pain, infertility, and tubal pregnancies. Even though only one-third to one-half of cases of PID are due to infection with Chlamydia trachomatis or Neisseria gonorrhoeae, most women with PID are treated with antibiotics directed toward these bacteria. However, in a recent study of women with clinically suspected PID, researchers frequently isolated gram-negative and anaerobic gram-positive bacteria, which were strongly associated with endometritis. Due to this finding, the researchers recommend that all women with PID be treated with medication regimens that include the broad-spectrum antibiotic, metronidazole.
This approach could potentially reduce the frequency of infertility, chronic pelvic pain, recurrent PID, and ectopic pregnancy after treatment, according to the researchers. Current guidelines from the Centers for Disease Control and Prevention recommend treatment of PID with ofloxacin, levofloxacin, ceftriaxone plus doxycycline, or cefoxitin plus doxycycline, all with or without the addition of metronidazole for full coverage against anaerobes and bacterial vaginosis.
The researchers investigated the associations of endometritis with N. gonorrhoeae, C. trachomatis, bacterial vaginosis, anaerobic bacteria, facultative bacteria, and lactobacilli among 278 women with complete endometrial histology and culture. Women with acute endometritis were less likely to have lactobacilli but much more likely to be infected with C. trachomatis, N. gonorrhoeae, diphtheroids, black-pigmented gram-negative rods, and anaerobic gram-positive cocci and to have bacterial vaginosis. This study is part of the PID Evaluation and Clinical Health (PEACH) study and was supported in part by the Agency for Healthcare Research and Quality (HS08358).
Details are in "Bacterial vaginosis and anaerobic bacteria are associated with endometritis," by Catherine L. Haggerty, Ph.D., Sharon L. Hillier, Ph.D., Debra C. Bass, M.S., and others, in the October 1, 2004, Clinical Infectious Diseases 39, pp. 990-995.