Endometritis refers to inflammation or infection involving the endometrium. Endometritis can be acute or chronic and may arise in an obstetric setting, such as following delivery or miscarriage, or in a nonobstetric setting due to pelvic inflammatory disease (PID) or endometrial instrumentation.
It complicates 2-3% of vaginal deliveries as well as up to 85% of Caesarean sections 5.
Endometritis is the most common cause of fever in a postpartum patient 6.
The typical presentation is with fever and lower abdominal pain. While imaging features can be helpful, the diagnosis is clinical as imaging can be normal, particularly in uncomplicated cases.
Recognised associations include 3:
- prolonged labour
- premature rupture of membranes
- retained intrauterine clots
- retained products of conception
Endometritis is a clinical diagnosis and caution should be taken due to the overlap of expected postpartum imaging findings and the ones related to the inflammatory process.
While the sonographic appearance of the uterus and endometrium may be normal in early stages, findings may include:
- thickened and heterogeneous endometrium
- intracavitary/cul-de-sac fluid
- increased vascularity on Doppler ultrasound
- intrauterine air
- T2: the uterus may be enlarged with overall high signal intensity
- T1 C + (Gd): can show intense enhancement of the uterus
Treatment and prognosis
- progression to a pyometrium
- pelvic septic thrombophlebitis
Differential considerations include:
- retained products of conception: echogenic material in the endometrial cavity showing intrinsic vascularity
- endometrial carcinoma: can have overlapping sonographic features but will occur in a different clinical context 1
- intrauterine blood clot
- no associated vascularity
- 1. Dubinsky TJ, Stroehlein K, Abu-ghazzeh Y et-al. Prediction of benign and malignant endometrial disease: hysterosonographic-pathologic correlation. Radiology. 1999;210 (2): 393-7. Radiology (full text) - Pubmed citation
- 2. Kido A, Togashi K, Koyama T et-al. Diffusely enlarged uterus: evaluation with MR imaging. Radiographics. 23 (6): 1423-39. doi:10.1148/rg.236035033 - Pubmed citation
- 3. Nalaboff KM, Pellerito JS, Ben-levi E. Imaging the endometrium: disease and normal variants. Radiographics. 21 (6): 1409-24. Radiographics (full text) - Pubmed citation
- 4. Schmidt W, Kurjak A. Color Doppler Sonography in Gynecology and Obstetrics. Thieme Medical Publishers. (2004) ISBN:1588902560. Read it at Google Books - Find it at Amazon
- 5. Wolfgang Dähnert. Radiology Review Manual. ISBN: 9781451153644
- 6. Gupta A, Desai A, Bhatt S. Imaging of the Endometrium: Physiologic Changes and Diseases: Women's Imaging. (2017) Radiographics : a review publication of the Radiological Society of North America, Inc. 37 (7): 2206-2207