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to OBSTETRICS & GINECOLOGYEndometriosis is a disorder in which abnormal growths of tissue ,histologically resembling the endometrium,are present locations other than the uterine lining..Although endometriosis can occour very rarely in postmenopausal women,it is found almost exclusively in women of reproductive age. All other manifestations of endometriosis exhibit a wide spectrum of expression.The lesions are usually fond on the peritoneal surfaces of the reproductive organs and adjacent structures of the pelvis,but they can occur any where in the body.The size of the individual lesions variesfrom microscopic to large invasive masses that erode into underlying organs and cause extensive adhesion formation.In the uterineendometriosis the lesion is in the miometrium which is invaded by endometrium from within,this condition is generally called adenomiosis.
The cause of endometriosis is unknown.Several theories have been offered to explain its occurrence,but none have sactisfactorily explained all of the features of the disease.
Atheory of retrograde menstruation was proposed during the 1920s. It was postulated that endometrioses occurred because viable fragments of endometrium were shed at the time of menstruation and passed through the uterine tubes,the tissuebecame implanted on peritoneal surfaces and grew into endometriotic lesions.This theory is simple and atractive but it does not explain why all women do not develop endometriosis or the rare cases of endometriosis in the lung ,brain,or other soft tissues or in nonmentruating subjects (S. Turneror absent uteri).
Other workers proposed that endometrial tissue could be transported by lymphaic or hematogenous routes,and a theory of coelomic metaplasia was postulated.In the latter,peritoneumis induced to under go metaplasia into endometrial tissue by some stimulus(menstrual fluid or other irritants, cyclic ovarians hormones,etc).
A role for the immune sistem in the origin of the endometrisis was suggested by workers studying monkeys with spontaneus endometriosis that mounted a lesser immune response to endometrial antigens tan control animals. also,the peritoneal fluid of women with endometriosis has been noted to have increased immunossupressive properties and lymphocytes with decreased natural killer cell activity.
Genetic influences in the development of endometriosis have been discribed.Further investigation failed to link endometriosis with the presence of a particular HLAantigens.
The gross appearence of endometriosis at operation is usually quite characteristc.The smallest implants are red,pethechial lesions on the peritoneal surface.With further growth,menstrual like detritus accumulates within the lesions,giving a cystic,dark brown,dark blue,or black appearence.The surrounding peritoneal surface becomes thickened and scarred.When present on the ovary,cysts may enlarge to several centimeters in size and are called endometriomas or chocolate cysts.Severe disease can erodeinto underlying tissues and distort the remaining organs with extensives adhesions.In addition to these traditionalpresentations,endometriosis lesions can have a variety of a nonclassical appearences:clear vesicles,white or yellow spots or nodules,circilar folds of peritoneum(pockets)and lesions so small only be deteced microscopically.
The distribuition of lesions exhibits cacharacteristc pattern.The most common site of desease is the ovary,followed by the uterine cul-the-sac,uterosacral ligaments,the posterior surfaces of the uterus and broad ligament,and the remaining pelvic peritoneum.Implants can occour over the bowel,blader,and the ureters;rarely they may erode into underlying tissue and cause blood in the stool or urine,or their associated adhesions may results instricture and obstruction of these organs.Very rarely,endometriosis is found distant from the pelvis,in such sites as the lung,brain,and kidney.Pleural implantations are associated with recurrent right pneumotoraces at the time of the menses(catamenial pneumotorax).Similarly,lesions inthe central nervous sistem can cause catamenial seizures.
The microscope finding that these lesion are composed of tissue histologically resembling endometrial glands and stroma gives endometriosis its name.However,further assumptions about similarities between the tissues must be made with great caution.Simultaneus biopsies of implants and endometrium have found the implants often to be histologically out of phase with the uterine tissue.Also the characteristic changes of estrogens and progesterone receptors presents in endometrium across the menstrual cycle are absent in endometriosis implants.
Infertilityand pelvic pain are the cardinal simptoms.
Pain is produced by pressure and inflamation within and aroud the lesion, by traction on adhesions, by the number of the implants and their proximity to nerves and others sensitive structures, and by the mass efect of the large lesions. Although this sequence of events explains why premenstrual pelvic pain occur in endometriosis, it is incomplete, because many patients with extensive endometriosis have no pain. Dispareunia is often present.Adhesions from endometriosis may cause disconfort at any time of the cicle, and sensation of pelvic pressure may result if lage masses are present. Premenstrual spottinf may occur and is more likely to be associated with endometriosis than with luteal-phase inadequancy.
The relationship between endometriosis and infertility has been more extensively investigate.Its not difficult to understand how advanced disease can result in infertility, because its association with adhesions that distort pelvic anathomy, prevent a normal tubo-ovarian apposition, and encasethe ovary. But minimal or mild endometriosis, in with pelvic anatomy isentirely normal exept for a few peritonial surface lesions, can also cause infertility. The mechanism by with this occurs is unknow.Various theories have been proposed to explain this phenomenon: Alteration in peritoneal fluid volume, elevations in peritoneal fluid prostaglandins F2 alpha and E2, several disorders of menstrual cyclicity and ovulation, an ncreased incidence of lutheal phase deficiency, immunologic phenomena and deficiency in celular immunity to endometrium.
It must be enphasized, that many ptients either have no symptoms or have infertility as their only symptom and that the extend of desease often has little correlation with the severity of the symptoms.
The physical examination may be helpful in dicerning whether endometriosis is present. Classicaly, pelvic examination reveals tender nodules in the posterior vaginal fornix and pain upon uterine motion.The uterus may be fxed and retroverted due to cul-de-sac adhesions, and tender adnexial masses may be felt because the presence of endometriomas .Careful inspection may reveal implants in healeds wounds especially episiotomy and cesarean section incisions, in the vaginal fornix, or on the cervix.Biopsy may be required to prove that the lesions are due to endometriosis
Endometriosis shoud be suspected in any patient of reproductive age complaining of pain or infertility. Medical treatment can be given for pelvic pain thought to be to endometriosis , but the specific diagnosis shoud not be made unless documented by direct visualization. The final diagnosis of endometriosis can only be made at laparoscopy or laparotomy, by direct observation of the implants.
Treatment options are dictated by the patient’s desire for future fertility, her symptoms, thstage of her disease, and to some extend her age. It must be emphasized that therapy for endometriosis requires operative inspection of the lesions for correct diagnosis and staging and to be sure that the patient’s symptoms are attributable to endometriosis only.
Observation
In asymptomatic patients, those mild discomfort, or infertile women with minimal or mild endometriosis, expectant managment may be appropriate.
Analgesic Therapy
It is appropriate when the patient has mild premenstrual pain from minimal endometriosis, no adnormalities on pelvic examination, and no desire for immediate fertility.
Pseudopregnancy
The aim of the therapy is to creata constant high levels of progestins, as seen in pregnancy, to thin the endometrium and cause its regression with pseudodecidual changes. Medroxyprogesterone acetate, 10-30 mg daily, is commonly given, as are continuous oral contraceptive pills. Current, pseudopregnancy is best reserved for patients with milder forms of endometriosis who do not desire immediate fertility and unable to take other treatments
.Pseudomenopause
In this treatment, a medication attempts to reduce endogeneous estrogen and progesterone production to constant low levels. This therapy is the medical treatment for choice for endometriosis.
Danazol - It acts at the hypothalamic level to inhibit gonadotropin release, which in turn lowers ovarian production of sex steroids and prevents ovulation. The dosage of danazol is 800 mg/d in divided doses for 6 months. In mild endometriosis, danazol treatment is probably no better than expectant management, and patients with severe disease wil not see resolution of their adhesions or endometriomas from this therapy. Endometriosis symptoms usually recur several months after treatment.
GnRH agonists - Gonadotropin-releasing hormone (GnRH) agonists are congeners of the 10-amino-acid peptide hormone GnRH.
Surgical Treatment
In women with complaints of infertility who have severe disease or adhesions or are older, conservative surgical therapy is the treatment of choice. If the patient not desire future childbearing and has severe disease or symptons, definitive surgery is appropriate and often curative. This entails total abdominal hysterectomy, bilateral salpingooophorectomy, and excision of remaining adhesions or implantations. If endometriosis remains after excision, postoperative medical therapy may be indicated.
Assisted Reproduction
Infertile women with endometriosis who are older, or who have failed other therapies for infertility, can undergo assisted reproduction (in vitro fertilization, gamete intra-fallopian transfer, etc) with success rates similar to those seen in women with other diagnoses.
Long-term concerns must be more guarded in that all current therapies offer relief but not cure. The course of endometriosis in any individual is impossible to predict at present, and future treatment options should greatly improve what can now be offered.
2-Coates Jeff,Principles of gynaecology-Fifth Edition
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