What is the diagnostic workup for a woman of reproductive age presenting with symptoms suggestive of Endometriosis and Adenomyosis, such as pelvic pain, heavy menstrual bleeding, and infertility?

Diagnostic Workup for Endometriosis and Adenomyosis

Begin with transvaginal ultrasound (TVUS) as your first-line imaging modality, using expanded protocol TVUS when deep endometriosis is suspected, and proceed to MRI pelvis without IV contrast if ultrasound is inconclusive or for surgical planning. 1

Clinical Assessment Framework

Essential History Elements

• Pain patterns: Specifically assess for dysmenorrhea, dyspareunia, dyschezia (painful defecation), and dysuria 1
• Infertility: Present in approximately 50% of endometriosis cases and 20-68% overall when considering both conditions 1, 2
• Heavy menstrual bleeding: Common presenting symptom, particularly with adenomyosis 3, 4
• Chronic pelvic pain: Document duration, severity, and relationship to menstrual cycle 1

Physical Examination Findings

• Pelvic examination: Assess for nodularity, fixed retroverted uterus, or tender uterosacral ligaments 1
• Speculum examination: Evaluate for visible endometriotic lesions 2
• Bimanual examination: Assess uterine size, mobility, and tenderness; enlarged, tender uterus suggests adenomyosis 3, 2

Imaging Algorithm

First-Line Imaging: Transvaginal Ultrasound

Standard TVUS combined with transabdominal ultrasound is the initial imaging study, allowing assessment of both endometriosis and adenomyosis 5, 1, 6

For suspected deep endometriosis, use expanded protocol TVUS which requires: 1

• Evaluation of uterosacral ligaments
• Assessment of anterior rectosigmoid wall
• Dynamic sliding maneuvers to detect adhesions
• Bowel preparation or enema for optimal visualization
• Evaluation of appendix and diaphragm when indicated

Performance characteristics: 1, 2

• Sensitivity 82.5%, specificity 84.6% for endometriosis overall
• Up to 96% sensitivity and 99% specificity for deep infiltrating endometriosis with expanded protocol
• Comparable to MRI for deep endometriosis detection when expanded protocol is used

For adenomyosis diagnosis on ultrasound: 3, 4

• Look for myometrial thickening, heterogeneous myometrial texture
• Identify subendometrial linear striations and myometrial cysts
• Note that sensitivity drops to 33.3% when coexisting leiomyomas are present

Second-Line Imaging: MRI Pelvis

MRI pelvis without IV contrast is indicated when: 1, 6

• TVUS is inconclusive or endometrium cannot be fully visualized
• Surgical planning is needed for deep infiltrating disease
• Coexisting pathologies like leiomyomas obscure ultrasound findings

MRI performance characteristics: 1

• 90.3% sensitivity and 91% specificity for deep pelvic endometriosis overall
• 92.4% sensitivity and 94.6% specificity for intestinal endometriosis
• 88% sensitivity and 83.3% specificity for deep infiltrating endometriosis in posterior locations
• 78% sensitivity and 93% specificity for adenomyosis when ultrasound is equivocal 6

Key MRI findings: 1

• Endometriosis: T2 hypointense fibrosis at torus uterinus and uterosacral ligaments, T1 hyperintense hemorrhagic foci (endometriomas), T2 dark spot sign, obliteration of pouch of Douglas
• Adenomyosis: Junctional zone thickening, myometrial cysts, heterogeneous myometrial signal

Technical optimization: 1

• Moderate bladder distention improves lesion conspicuity
• Vaginal contrast enhances visualization of deep infiltrating disease
• Add IV contrast specifically to differentiate endometriomas from ovarian malignancies, though not routinely needed for detecting deep endometriosis itself

Alternative Advanced Imaging

Transrectal ultrasound can be considered for deep infiltrating endometriosis with 97% sensitivity and 96% specificity for rectovaginal disease 1

Laboratory Testing

Limited Role of Biomarkers

• CA-125: Has no clinical utility for diagnosis; may be helpful for monitoring clinical response in confirmed extrauterine disease, but can be falsely elevated due to peritoneal inflammation or infection 1
• Pregnancy test: Essential to rule out pregnancy-related bleeding 6
• Hemoglobin level: Assess for anemia from heavy menstrual bleeding 6, 7

Tissue Diagnosis Considerations

When Endometrial Sampling is Needed

Endometrial biopsy is essential in perimenopausal women with heavy menstrual bleeding to exclude endometrial cancer or hyperplasia, even with normal imaging 6, 7

Surgical Diagnosis

• Laparoscopy with histologic confirmation is no longer required before initiating empiric treatment for endometriosis 1
• Surgery is now reserved for definitive treatment rather than diagnosis 1
• Preoperative imaging reduces morbidity by decreasing incomplete surgeries requiring reoperation 1

Critical Pitfalls to Avoid

Imaging Errors

• Do not rely on standard TVUS alone for deep endometriosis—expanded protocols or MRI are essential 1
• Do not use CT pelvis as initial imaging—it has no role in standard endometriosis diagnosis 5, 1
• Do not assume negative imaging excludes endometriosis—superficial peritoneal disease is poorly detected by all imaging modalities 1

Clinical Errors

• Do not delay empiric treatment waiting for surgical confirmation—diagnosis is fundamentally clinical 1
• Do not miss coexisting adenomyosis—it frequently coexists with endometriosis and affects treatment success 6, 2, 8
• Do not overlook the need for endometrial sampling in perimenopausal women, even with imaging findings suggesting benign structural causes 6, 7

Classification Systems for Documentation

When endometriosis is confirmed, use the classification toolbox approach: 5

• r-ASRM classification: Longest established, widely used, incorporated into other systems
• Enzian classification: Specifically for deep endometriosis characterization
• Endometriosis Fertility Index (EFI): Valuable for predicting fertility outcomes post-surgery 2

Note that these classification systems have poor correlation with pain symptoms but are useful for surgical planning and fertility counseling 5