Stage-wise comparison of anti-endometrial-antibodies against peptides of SLP2, TMOD3 and TPM3 in diagnosis of endometriosis

Abstract

The lack of non-invasive diagnostic test for early diagnosis of endometriosis results in 8-11 years delay in diagnosis leads to deterioration of quality of life. Previously, we identified anti-endometrial-antibodies against peptides of Stomatin like protein 2 (SLP2), Tropomodulin 3 (TMOD3) and Tropomyosin 3 (TPM3), and further proposed their utility as non-invasive biomarkers for early diagnosis of endometriosis.The aim of the present study was to investigate whether the levels of biomarkers vary with disease progression and to compare the sensitivity, specificity and diagnostic accuracy of the biomarkers in diagnosis of endometriosis in early stages (Stage I-II) versus advanced stages (Stage III-IV). Multi-centre, cross sectional study Women with endometriosis (Stage I-II n=133, Stage III-IV n=133)and healthy controls (n=104) were screenedfor eleven novel autoimmune markers (anti-endometrial-antibodies of SLP2a, SLP2b, SLP2c, TMOD3a, TMOD3b, TMOD3c, TMOD3d, TPM3a, TPM3b, TPM3c and TPM3d) using the peptide ELISA.The statistical analysis was performed using STATA software (version 8.2, Texas, USA). The mean serum levels of anti-endometrial-antibodies of SLP2a, SLP2b, SLP2c, TMOD3a, TMOD3b, TMOD3c, TMOD3d, TPM3a, TPM3b, TPM3c and TPM3d) in early stages (Stage I-II) were significantly higher than that of advanced stages (Stage III-IV) of endometriosis (p<0.05). The sensitivity and diagnostic accuracy of all these biomarkers were higher in detection of Stage I-II endometriosis than in the detection of Stage III-IV endometriosis at an acceptable specificity of ≥60%. We observed that the levels of serum anti-endometrial antibodies to SLP2, TMOD3 and TPM3 did not appear to elevate further in advanced stages (Stage III-IV) of endometriosis.