Endometriosis Diagnosis
History
- Should include:
- Age (reproductive year, most commonly at 25-29 years old)
- In utero exposure to environmental toxins like diethylstilbestrol which increases the incidence of endometriosis
- Family history of endometriosis (7x higher risk than with no family history)
Physical Examination
- Ideally done during early menses because endometrial implants are likely to be largest and deep infiltrating, hence more easily detectable
- Perform abdominal inspection and palpation, a rectovaginal examination, and assess the uterus’ mobility, position and size
- Diagnosis is more definite if deeply infiltrative nodules are found on the uterosacral ligaments or in pouch of Douglas, and/or lesions are directly seen in the vagina or cervix
- Note that there may be no abnormal findings on physical exam
- For patients who are not sexually active, a rectal-abdominal exam may be better tolerated than a vaginal-abdominal exam
- A cotton swab can be inserted into the vagina to document patency and exclude complete or partially obstructive anomalies such as a transverse vaginal septum, imperforate or microperforate hymen, or an obstructed hemivagina
- Pain with uterine movement or pelvic tenderness
- Tender, enlarged adnexal masses
- Fixation of adnexa or uterus in a retroverted position
Laboratory Tests
- Urinalysis and urine culture to identify pain originating in the urinary tract (eg cystitis, stones)
- Pregnancy test and tests for sexually transmitted infection (STI) like gonorrhea, chlamydia, when appropriate
Serum CA-125
- Women with endometriosis may have high serum CA-125 concentration
- No value as diagnostic tool in endometriosis, though it may be used to assess the presence of an undiagnosed adnexal mass
- Also elevated in ovarian epithelial neoplasia, myoma, adenomyosis, acute pelvic inflammatory disease (PID), ovarian cyst, pregnancy
Imaging
Transvaginal Sonography (TVS)
- Considered the 1st-line imaging tool to examine suspected endometriosis
- Should be performed to determine whether a pelvic mass or structural anomaly is present
- Useful in diagnosing or excluding rectal endometriosis
- May identify an ovarian endometrioma and help identify other structural causes of pelvic pain, such as ovarian cysts, torsion, tumors, genital tract anomalies and appendicitis
- Distinguishes endometrioma from other ovarian cysts with 83% sensitivity and 89% specificity
- Ovarian endometrioma may be diagnosed in premenopausal women with findings of ground glass echogenicity and 1-4 compartments and absence of papillary structures with blood flow
- May be helpful in some cases to better define an abnormality suspected by sonography
- Detects ovarian endometrial cysts with 90% sensitivity and 98% specificity
- Provides exact location of deep retroperitoneal lesion
- May be used as part of pre-op workup, but should not be used as 1st-line
- Cystoscopy, colonoscopy and rectal ultrasonography may be required if deep endometriosis is suspected
Surgical Tests
Laparoscopy
- Gold standard for diagnosis, unless lesions are visible in the vagina
- May also be used for therapeutic purposes
- Should not be done during or within 3 months of hormonal treatment to avoid under-diagnosis
- Biopsy and histopathologic study of at least one lesion is ideal
- 3 cardinal features (ie ectopic endometrial glands, ectopic endometrial stroma, and hemorrhage into adjacent tissue) should be present
- In adolescents, features of endometriosis may be atypical (ie clear vesicles and red lesions)
- A negative laparoscopy does not exclude the diagnosis of endometriosis
- Depending on the severity of the disease found, it is best to remove the endometriotic lesion at the same time
- Differential diagnoses (eg endosalpingiosis, mesothelial hyperplasia, hemosiderin deposition, hemangiomas, adrenal rests, inflammatory changes, splenosis and reactions to oil-based radiographic dyes) can be excluded by biopsy
- Revised American Society for Reproductive Medicine (rASRM) Score [formerly the Revised American Fertility Society (rAFS) Score]
- Noted aspects include bilaterality, depth of invasion, size, involvement of the ovary and cul-de sac, and density of adhesions
- Scores are as follows: 1-5 minimal disease (stage I), 6-15 mild disease (stage II), 16-40 moderate disease (stage III), >40 severe disease (stage IV)
- Does not take into account the retroperitoneal structures and deep infiltrating endometriosis
- Enzian Staging System
- Presence of deep infiltrating endometriosis is taken into account
- Supplements the rASRM score with a description of deep infiltrating endometriosis, retroperitoneal structures and other organ involvement
- May be considered in suspected endometriosis lesions and endometriomas to help confirm the diagnosis and exclude possible malignancy
- Recommended for the diagnosis of patients with mild to moderate endometriosis
- In patients with endometriosis, prevalence of ovarian cancer is <1%