Combination of non-invasive and semi-invasive tests for diagnosis of minimal to mild endometriosis

Non-surgical diagnostic approach for endometriosis would be of great gain to both physicians and patients. The aim of this study was to evaluate the diagnostic value of serum measurement of IL-6 combined with the presence of nerve fibres in the functional layer of endometrium for diagnosis of minimal-mild endometriosis. In this prospective study 114 women who underwent laparoscopy for infertility and/or pelvic pain were divided into two groups: control cases (40 cases) with no pathologic findings; and endometriosis patients (74 cases) {[}subdivided into stages 1-2 or minimal-mild (MM) and stages 3-4 or moderate-severe cases]. Blood was drawn one day before laparoscopy and stored for subsequent analysis of IL-6. Endometrial biopsy was obtained prior to laparoscopy and Immunohistochemistry was performed using the pan-neuronal marker protein gene product 9.5(PGP9.5). Then laparoscopic diagnosis of endometriosis confirmed by histopathology was done. Serum IL-6 with a threshold of 15.4 pg/ml was found to be able to diagnose MM endometriosis with 89.5 \% sensitivity and 82.5 \% specificity, but sensitivity and specificity of presence of nerve fibres in the functional layer of endometrium were 92 \% and 80 \% respectively. When two diagnostic modalities were combined the sensitivity and specificity were raised to 100 and 92.5 \% respectively. Combination of both serum IL-6 and presence of nerve fibres in the endometrium is more reliable method for diagnosis of MM endometriosis than in single test.