Endometriosis

Definition: presence of normal endometrial mucosa abnormally implanted in locations other that the uterine cavity

Typical locations of endometriosis:
 - ovaries
 - fallopian tubes
 - vagina
 - cervix
 - uterosacral ligaments
 - rectovaginal septum

Pathophysiology:
- commonly located in the dependent portions of the female pelvis
- ectopic foci respond to cyclic hormonal fluctuations the same way as intrauterine endometrium (proliferation, secretory activity, and cyclic sloughing of menstrual material)
- products of metabolic activity, release of cytokines and prostaglandins, leading to an altered inflammatory response characterized by neovascularization and fibrosis formation

Risk Factors:
1) Family History of Endometriosis
2) Early age of menarche
3) Short menstrual cycles (<27d)
4) Long duration of menstrual flow (>7d)
5) Heavy bleeding during menses
6) Inverse relationship to parity
7) Delayed childbearing
8) Defects in the uterus or fallopian tubes
9) Hypoxia and iron deficiency may contribute to early onset of endometriosis

History:
1) one-third of the patients are asymptomatic
2) Symptoms:
       - secondary dysmenorrhoea,
       - metromenorrhagia,
       - pelvic pain,
       - lower abdominal/ back pain,
       - dyspareunia,
       - dyschezia often with cycles of diarrhoea and constipation,
       - bloating,
       - nausea,
       - vomiting,
       - inguinal pain,
       - dysuria,
       - increased frequency of urination,
       - pain during exercise

Physical Examination:
1) tenderness at sides of involvement
2) nonspecific pelvic tenderness
3) tenderness best detected during menses
4) acute abdomen in case of rupture of an ovarian endometrioma
5) involvement of GI tract may cause adhesions and obstructions
6) should also include evaluation for cervicitis, abnormal discharge, STDs

Differential Diagnoses:
1) Appendicitis,
2) Chlamydial GU infection
3) Diverticulitis
4) Ectopic pregnancy
5) Gonorrhoea
6) Ovarian cysts
7) Ovarian torsion
8) Pelvic inflammatory disease
9) UTI

Laboratory Studies:
1) Complete blood cell - differentiate pelvic infection from endometriosis
2) Urinalysis, urine culture -  to rule out UTI
3) Serum cancer antigen 125 (CA - 125) test - serial measurements useful as prognosticators of treatment outcome

Ultrasonography
1) transvaginal ultrasonography - endometriomas - internal echoes to solid masses
                                                - chocolate cyst - homogenous internal echoes consistent with old blood

Laparoscopy
- considered as primary diagnostic modality for endometriosis
- 97% sensitivity, 77% specificity
- protean in appearance
- classic lesions: blue-black or have a powder-burned appearance
- can be red, white, or nonpigmented
- peritoneal defects and adhesions are also indicative
- common sites: ovaries, posterior cul-de-sac, broad ligament, uterosacral ligament, rectosigmoid colon, bladder, distal ureter
- Histologic features: endometrial glands and stroma in biopsy specimens obtained from outside of uterine cavity. Finding of fibrosis in combination with hemosiderin-laden macrophages.

Treatment:

Medical
1) Progesterone: medroxyprogesterone acetate, norethindrone acetate, megestrol
              - induce decidualization and resorption of endometriosis
2) Combined contraceptive pill:
             - desogestrel and ethynil estradiol, norgestimate/ ethinyl estradiol
             - induces decidualization of ectopic endometrium
3) Danazol
             - steroid hormone closely related to testosterone, inhibits pituitary gonadotrophins
             - antioestrogenic, antiprogestational, androgenic and anabolic
4) Gonadotrophin releasing hormone analogues (GnRH analogue)
             - goserelin, leuprolide, nafarelin
             - depot injection or nasal spray
             - causing desensitization of Pituitary receptors, suppressing ovarian function, causing hypo-
                oestrogenism state and regression of endometrioid deposits

Surgical
1) radical surgery
              + total hysterectomy and bilateral oophorectomy indicated for women who has completed her
                 family
              + adhesiolysis is performed to restore mobility and normal intrapelvic organ relationships
2) conservative surgery:
              + reproductive potential is retained
              + using laparoscopic bipolar diarthermy or laser
              + recurrence 19%, relieving pelvic pain in 87% of patients
3) semiconservative surgery:
              + indicated for women who already completed family but too young for surgical menopause
              + hysterectomy and cytoreduction of pelvic endometriosis
              + ovarian function is retained