Danazol but not gonadotropin-releasing hormone agonists suppresses autoantibodies in endometriosis

The effects of fetal exposure to danazol

OBJECTIVE

To assess the consequences of exposure to danazol in utero. Additionally, by assessing the risk, to facilitate the counselling of pregnant women inadvertently exposed to danazol in early pregnancy.

DESIGN

Retrospective review of reported case histories.

SUBJECTS

129 women exposed to danazol during pregnancy were identified from individual case reports, data from the Australian Drug Reactions Advisory Committee and the United States Food and Drug Administration and from the reports of danazol exposure made directly to the manufacturers.

MAIN OUTCOME MEASURES

Teratogenic effects of fetal exposure to danazol in relation to dosage and duration of exposure.

RESULTS

Of the 129 reported pregnancies, 12 miscarried and 23 were aborted. Of the 94 completed pregnancies, 37 resulted in the birth of normal males, 34 in non-virilized females and 23 in virilized females. Virilization occurred in a proportion of female fetuses with a pattern of cliteromegaly, fused labia and urogenital sinus formation. Surgery to the genital tract was usually, but not always, required in childhood. The abnormality has not been reported where danazol therapy had been discontinued before the 8th week of pregnancy. Although more common in the higher dosages, virilization was reported in one case with a 200 mg daily dosage.

CONCLUSIONS

Danazol should remain contraindicated in pregnancy and clinicians should give careful contraceptive advice to patients commencing or continuing danazol therapy. Nonetheless it is possible to be cautiously optimistic about the outcome of danazol-exposed pregnancies, particularly if treatment is discontinued before 8 completed weeks gestation.

Autoreactivity in women with endometriosis

Serum samples from 71 patients with laparoscopically staged endometriosis and from 109 age-matched non-pregnant control women were tested for antibodies to nuclear, phospholipid, smooth muscle and sperm antigens. Immunoglobulin G, M and A and complement components C3 and C4 were measured. Prevalence of the following autoantibodies was statistically significantly greater in women with endometriosis than in the control group: antinuclear antibodies, antibodies to ribonucleoproteins, smooth muscle antibodies, lupus anticoagulant and anticardiolipin antibody. Forty-one women with endometriosis (58%) had some type of autoantibody compared with 13 controls (12%). More women in the endometriosis group had IgG and IgM levels above the normal range. This was statistically significant for IgG in women with grade 3 and for IgM in those with grade 4 endometriosis, IgG levels were significantly higher in antibody-positive women with endometriosis than in the control group. Immunoglobulin and complement component levels tended to have a positive correlation with stage of disease.

Nafarelin acetate: a gonadotropin-releasing hormone agonist for the treatment of endometriosis

Nafarelin acetate is a gonadotropin-releasing hormone (GnRH) agonist proven as effective as danazol in treating endometriosis. Its proposed mechanism of action is the desensitization of pituitary GnRH receptors leading to a decrease in gonadotropin release, and ovarian hormone serum concentrations similar to those achieved in postmenopausal women. Nafarelin decreases or ablates the physical symptoms associated with endometriosis, and pregnancy rates following therapy with this drug are comparable to rates observed after danazol therapy. Nafarelin is administered by nasal inhalation and has been generally well tolerated. It is associated with a high incidence of adverse effects but they are rarely severe enough to cause withdrawal from treatment, and those occurring most frequently--hot flashes, vaginal dryness, and decreased libido--are a consequence of the hypoestrogenemia induced by the drug. Increased bone turnover occurs in women on nafarelin but biochemical parameters return to pretreatment concentrations by six months after termination of treatment. This agent's place in the therapy of endometriosis will be determined as clinical experience accumulates.

Localization of anti-endometrial antibody binding in women with endometriosis using a double-labelling immunohistochemical method

Anti-endometrial antibody binding was localized using a double-labelling immunohistochemical method on frozen sections of endometrium taken from a woman without pelvic disease. Serum from 40 women with endometriosis was tested and, as controls, serum samples from 20 adult males and 20 umbilical cords. The method allowed compensation for endogenous immunoglobulins in endometrium and accurate localization of anti-endometrial antibody binding in the cytoplasm of the glandular epithelium. Significantly more women with endometriosis (14/40) were found to have anti-endometrial antibodies than controls (1/40) (P less than 0.001; chi 2). There was no correlation between disease severity and the presence of anti-endometrial antibodies or the intensity of staining.

Immunological aspects of surgically induced experimental endometriosis: variation in response to therapy

Elevated endometrial antibody titers were detected in serum and peritoneal fluid of rabbits with experimentally induced endometriosis. Surgical extirpation of implants or suppression with gonadotropin-releasing hormone agonist resulted in decreased endometrial antibody titers, whereas the antibody titers in untreated rabbits with endometriosis increased significantly. Endometrial implants and normal endometrial tissue had similar proteins by polyacrylamide gel electrophoresis. However, the serum and peritoneal fluid from rabbits with experimentally induced endometriosis had gamma G immunoglobulin antibodies to an endometrial protein with molecular weight of approximately 40 kD. These antibodies were absent in rabbits without endometriosis. Isolation of endometrial antigens eliciting the humoral immune response in endometriosis may aid in the development of a specific antibody marker for endometriosis.