What is the diagnostic workup for endometriosis (endometrial tissue growth outside the uterus)?

From the Guidelines

The workup for endometriosis should begin with a thorough medical history and physical examination, followed by transvaginal ultrasound as the first imaging study to evaluate pelvic organs and potentially identify endometriomas, as recommended by the American College of Radiology 1. The diagnosis of endometriosis can be challenging due to variable presenting symptoms and nonspecific physical examination findings.

• A thorough medical history and physical examination are essential to identify symptoms like pelvic pain, dysmenorrhea, dyspareunia, and infertility.
• Transvaginal ultrasound (TVUS) is often the first imaging study used to evaluate pelvic organs and potentially identify endometriomas, though it cannot definitively diagnose all forms of endometriosis 1.
• Expanded protocol TVUS studies have been developed to identify and "map" deep endometriosis (DE) and have shown excellent performance for detection of DE 1.
• MRI may be used in complex cases to better visualize deep infiltrating endometriosis, with a tailored protocol that includes moderate bladder distention and vaginal contrast to help improve lesion conspicuity involving these structures 1.
• Laboratory tests, including CA-125, may be checked but have limited diagnostic value due to poor specificity 1.
• Empiric treatment with hormonal therapy, such as combined oral contraceptives or progestins, can be both diagnostic and therapeutic, as improvement suggests endometriosis.
• However, laparoscopy with histological confirmation remains the gold standard for definitive diagnosis, allowing direct visualization and biopsy of endometriotic lesions, particularly important in cases with severe symptoms, when fertility is desired, or when other serious conditions like malignancy need to be excluded 1.

From the Research

Diagnostic Approaches for Endometriosis

• The initial diagnostic investigations for endometriosis include physical examination and pelvic ultrasound 2.
• Transvaginal ultrasound (TVS) is recommended as the first-line imaging modality for diagnosing endometriosis due to its satisfactory overall diagnostic accuracy, wide availability, and low cost 3.
• TVS is particularly useful for detecting ovarian endometriomas and deep infiltrating endometriosis (DIE) 4, 3.
• Magnetic Resonance Imaging (MRI) is commonly used to achieve a better anatomical overview of the entire pelvic organs and is particularly useful for detecting intestine or rectal nodules, as well as rectovaginal septum nodules 4, 5.

Clinical Evaluation and Management

• A thorough clinical evaluation, including a speculum examination and vaginal palpation, is essential for assessing the extent of endometriosis and determining the appropriate management approach 2.
• The Endometriosis Health Profile-30 (EHP-30) or its short version EHP-5, and the generic quality of life questionnaire SF-36, can be used to assess the quality of life in women with endometriosis 2.
• Management of endometriosis is recommended when it has a functional impact (pain, infertility) or causes organ dysfunction, and may involve a multidisciplinary approach 4, 2.

Challenges and Future Directions

• The diagnosis of endometriosis is often delayed due to inherent challenges, including a gold standard based on an invasive surgical procedure (laparoscopy) and diverse symptomatology 6.
• Increasing patient education and timely referral to a women's healthcare provider, as well as shifting the physician approach to the disorder, are essential for remedying the diagnostic delay 6.
• A practical algorithm that combines symptoms, signs, and clinical findings of endometriosis can simplify the diagnosis and make the process accessible to more clinicians and patients, culminating in earlier effective management 6.