Endometriosis vs. Endometritis: Key Distinctions
Endometriosis and endometritis are fundamentally different diseases—endometriosis is a chronic inflammatory condition where endometrial-like tissue grows outside the uterus causing pelvic pain and infertility, while endometritis is an acute or chronic infection/inflammation of the endometrium itself (the uterine lining).
Endometriosis: Chronic Systemic Disease
Definition and Location:
- Endometriosis is an inflammatory disease characterized by lesions of endometrial-like tissue outside the uterus that is associated with pelvic pain and/or infertility 1
- Affects approximately 10% of women during reproductive years, translating to 176 million women worldwide 2, 3, 4
- The tissue can be found on pelvic organs, peritoneum, ovaries, bowel (90% rectosigmoid), bladder, and other locations 5
Pathophysiology:
- This is a chronic, estrogen-dependent, progesterone-resistant disease with proliferative characteristics 2, 6
- Involves multifactorial etiology including genetic factors with epigenetic influences, environmental exposures, and chronic systemic inflammation 1, 6
- Now recognized as a systemic disease affecting metabolism, causing systemic inflammation, and altering brain gene expression leading to pain sensitization and mood disorders 7
Clinical Presentation:
- 90% of patients report pelvic pain including dysmenorrhea, nonmenstrual pelvic pain, and dyspareunia 3
- 26-50% experience infertility 2, 3
- Sacral backache with menses may indicate bowel involvement 5
- Diagnosis is typically delayed 5-12 years after symptom onset 3
Diagnosis:
- Definitive diagnosis requires surgical visualization with histological verification 3, 4
- Transvaginal ultrasound has 82.5% sensitivity and 84.6% specificity for deep disease 6
- Normal physical examination and imaging do not exclude the diagnosis 3
Endometritis: Uterine Lining Infection
Definition and Location:
- Chronic endometritis (CE) is a local mucosal inflammatory disorder of the uterine lining itself 8
- Histopathologically recognized by unusual infiltration of CD138+ plasmacytes into the endometrial stromal compartment 8
Pathophysiology:
- Major cause is intrauterine infection by common bacteria (Escherichia coli, Enterococcus faecalis, Streptococcus, Staphylococcus), Mycoplasma/Ureaplasma, and Mycobacterium 8
- Local dysbiosis in the female reproductive tract may contribute to onset and development 8
Clinical Presentation:
- Associated with female infertility and obstetric/neonatal complications 8
- Presents as an infectious/inflammatory process rather than a chronic systemic disease
Treatment:
- Antibiotic treatments against causative microorganisms are effective in eliminating endometrial stromal plasmacytes 8
- This represents a fundamental treatment difference from endometriosis
Critical Distinctions Summary
| Feature | Endometriosis | Endometritis |
|---|---|---|
| Location | Tissue outside uterus [1,2] | Inflammation within uterine lining [8] |
| Nature | Chronic systemic inflammatory disease [7] | Infectious/inflammatory disorder [8] |
| Cause | Multifactorial (genetic, hormonal, environmental) [6] | Bacterial infection [8] |
| Treatment | Hormonal suppression, surgery [3] | Antibiotics [8] |
| Diagnosis | Surgical visualization preferred [3] | Histopathology showing plasmacytes [8] |
Common Pitfall to Avoid
The similar terminology can cause confusion, but remember: endometriosis involves tissue growing in the wrong place (outside the uterus), while endometritis involves infection of the normal location (inside the uterus) 1, 8. These require completely different diagnostic and therapeutic approaches.