Approach Considerations
Although the diagnosis of endometritis is principally made on clinical grounds, laboratory studies can be helpful for supporting the diagnosis and excluding or identifying other diagnostic possibilities.
The 2010 and 2015 CDC guidelines on sexually transmitted diseases treatment agree that cervicitis can be a sign of endometritis and that women who are experiencing a new episode of cervicitis should be tested for endometritis, as well as other PID, gonorrhea, and chlamydia. [1, 2]
Endometrial biopsy can be obtained to assess chronic endometritis in the nonobstetric population. Chronic endometritis is associated with abnormal bleeding, recurrent abortion, and infertility. It is a subtle condition and is therefore difficult to diagnose. The diagnosis is ultimately based on the presence of plasma cells in the endometrial stroma upon histopathological examination. [15]
Chronic
Pathologically, endometritis is defined as the presence of 5 or more neutrophils per high-power field (400×) in the superficial endometrium and 1 or more plasma cells per high-power field (120×) in the endometrial stroma.
Complete Blood Cell Count
The CBC count typically reveals leukocytosis with a left shift. However, in the postpartum period, this finding may reflect the physiological leukocytosis of pregnancy and it is therefore unreliable for diagnosis.
Anemia is a risk factor for the development of endometritis.
Cultures
Blood culture is positive in 10-30% of cases, and a urine culture should be ordered.
The role of endocervical cultures is controversial. They are not generally helpful in management, as positive results are usually the result of contamination from normal resident cervicovaginal flora. However, endocervical cultures (or DNA probe) are obtained for gonorrhea and chlamydia when appropriate.
Gram Stain
Gram stain or wet mount of the vaginal discharge may be useful in ruling out endometritis. If no pus cells are observed in the Gram stain, the negative predictive value for endometritis is 95%.
Imaging Studies
Perform imaging studies on patients who do not respond to adequate antimicrobial therapy in 48-72 hours. CT scanning of the abdomen and pelvis may be helpful for excluding broad ligament masses, septic pelvic thrombophlebitis, ovarian vein thrombosis, and phlegmon.
Ultrasonography of the abdomen and pelvis may yield normal findings in patients with a clinical diagnosis of endometritis. Abnormal findings overlap with those of retained products of conception and intrauterine hematoma.
