Serum-soluble CD23 in patients with endometriosis and the effect of treatment with danazol and leuprolide acetate depot injection.

Activated B cells have recently been shown to produce soluble CD23 from their membranes. The serum-soluble CD23 concentration in 21 patients with pelvic pain diagnosed as having endometriosis and confirmed by histology, and in 18 patients without pelvic pain, who had a normal pelvis during laparoscopic sterilization, was studied by chemiluminescent enzyme-linked immunosorbent assay. The endometriosis patients were randomized to 3 months of either danazol or leuprolide acetate injection. Serum was taken before and after 3 months of therapy. The serum-soluble CD23 concentration was significantly elevated in patients with endometriosis when compared with the controls (P < 0.0001). There was no correlation between soluble CD23 concentrations and the severity of endometriosis (r = 0.48, P > 0.05). The serum concentration of soluble CD23 decreased significantly on treatment with danazol but not leuprolide acetate (P < 0.05). We conclude that the elevation of soluble CD23 in patients with endometriosis suggests that there is activation of B cells, which respond to danazol but not leuprolide acetate injection.