Endometriosis

Definition

• Endometriosis is defined as ectopic endometrium-like tissue.
• Adenomyosis is defined as endometrial tissue in the myometrium.
• Affected are 10% of women (fertile), 50% with chronic pain.
• The condition is a chronic, oestrogen-dependent disease.

Classification

RASRM

• The abbreviation rASRM stands for rev. classification of the Am. Society for Repr. Medicine.
• According to rASRM, what is assessed is the peritoneal/ovarian lesions, adhesions, Douglas pouch.
• The point score results in four stages (minimal to severe).
• The weakness of the rASRM classification is that it doesn't map DIE/organ involvement/pain.

#ENZIAN

• The #ENZIAN classification describes compartment-based, including deep infiltrating form.
• Compartment P stands for peritoneal endometriosis.
• Compartments O and T stand for ovaries; T: tubo-ovarian junction.
• Compartments A, B, and C stand for vagina/rectovaginal space, sacrouterine lig., rectum.
• The suffix F (for “far”) denotes A: adenomyosis, B: bladder, U: ureter, I: bowel, O: other.
• The size of the lesions is coded in 3 grades: <1 cm, 1–3 cm, >3 cm.

Aetiopathogenesis

Theories

• Sampson's transplantation theory states endometrial cells reach the abdomen retrogradely.
• Meyer's metaplasia theory states coelomic epithelium transforms into endometrial tissue.
• The archimetra theory explains adenomyosis via disturbed uterine peristalsis.
• For extragenital spread, lymphogenous and hematogenous spread is assumed.
• As no single theory explains all phenomena, it is assumed to be a multifactorial process with immune and genetic factors.

Risk and Protective Factors

• The risk of endometriosis is increased by early menarche, short cycles, nulliparity, family history.
• Outflow obstructions such as a vaginal septum increase the risk because they increase retrograde menstruation.

Why Fertility is Impaired

• Mechanical disturbances: Fertility is mechanically impaired by adhesions, tube/ovary displacement, Douglas obliteration.
• Functional disturbances: Functional disturbances include peritoneum, oocyte quality, implantation.
• Adenomyosis: In adenomyosis, there is the additional factor of disturbed junctional zone, altered uterine peristalsis.
• Time to pregnancy: About one in two to three women with endometriosis reports an increased time to pregnancy.

Clinical features

Four Ds

• The first D of the cardinal symptoms is dysmenorrhoea, i.e., pain with menstrual bleeding.
• The second D is dyspareunia.
• The third D is dyschezia, i.e., pain during defecation.
• The fourth D is dysuria.
• This series of cardinal symptoms is often supplemented by infertility as a fifth cardinal symptom.

Diagnostic Latency

• Between the first symptoms and the final diagnosis, there are on average years.
• A main reason for the diagnostic latency is the trivialisation of menstrual pain.
• There is no correlation between extent of lesions and severity of pain.

Locations

• Most commonly affected are the peritoneum, ovaries, sacrouterine ligg., pouch of Douglas.
• Genital endometriosis can also affect the rectovaginal septum, vagina, cervix.
• Extragenitally, lesions occur in the bowel, bladder, ureter, umbilicus, diaphragm, pleura.
• Abdominal wall endometriosis typically develops in a C-section scar with cyclical pain.

Appearance of Lesions

• Fresh, active lesions are red and well-vascularised.
• Older lesions are black-blue as powder-burn lesions.
• Burnt-out lesions are white, fibrotic with stellate scar retraction.
• An endometriotic cyst of the ovary is called an endometrioma (chocolate cyst).

More facts from the study questions

• The four 'D's of the cardinal symptoms are dysmenorrhoea, dyspareunia, dyschezia and dysuria.
• Dyspareunia is pain during sexual intercourse.
• There is no correlation between the extent of the lesions (stage) and the severity of pain.
• The patient's level of suffering is a central aspect of the medical history.
• It is assessed by analgesic use and limitations in daily life, among other factors.
• Endometriosis is the presence of endometrium-like tissue outside the uterine cavity.
• Adenomyosis is the specific form with this tissue present within the myometrium.
• Endometriosis is a chronic, oestrogen-dependent disease.
• With the fall in oestrogen levels in the postmenopause, the symptoms cease.
• Sampson's transplantation theory is one of the central hypotheses on the origin of endometriosis.

Diagnosis

Inspection and Speculum Examination

• Speculum examination: Using a bivalve speculum, one looks for bluish-red lesions in the posterior vaginal fornix.
• Diagnostics for suspected TIE: If there is suspicion of deeply infiltrating endometriosis, a targeted biopsy under vision is possible.
• Examination of the abdominal wall: During inspection, c-section scar for cyclical pain.

Palpation

• Bimanual examination: One palpates bimanually for size, position, mobility, and tenderness of the uterus.
• Finding in TIE: A bimanually fixed, retroverted uterus is suggestive of for DIE with adhesions.
• Rectovaginal examination: This is performed to to palpate for firm, painful nodules.
• Optimal timing for examination: The examination is most informative during/shortly after menstruation.

Role of Diagnostics

• Gold standard: The gold standard for confirming the diagnosis remains laparoscopy with histology.
• Laboratory diagnostics: In terms of laboratory tests, there is no specific laboratory marker.

Systematic Assessment

• The sliding sign tests mobility of uterus against rectum.
• A negative sliding sign means an obliteration of the pouch of Douglas by adhesions.
• A systematic search is also conducted for nodules on septum, ligaments, bladder & bowel wall.

MRI and Limitations

• MRI is superior to sonography for deep endometriosis with bowel/bladder involvement.
• Imaging generally fails to detect purely peritoneal endometriosis.
• In case of bowel involvement, colonoscopy/endorectal ultrasound for stenosis may also be considered.

Keep learning in the app

Further reading (selection)

1. StatPearls: Endometriosis (NCBI Bookshelf)
2. DocCheck Flexikon, Endometriose
3. DocCheck Flexikon, Endometriom

Cross-references