Evaluation of serum-based inflammatory and haematological markers in patients with endometriosis: A case-control...

To assess the diagnostic value of serum-based inflammatory and haematological markers in women with endometriosis, and determine their relationship with disease severity, including lesion characteristics.

This prospective study included 103 patients with endometriosis (aged 18-45 years) and 103 healthy controls. Serum C-reactive protein (CRP), albumin and complete blood counts were obtained pre-operatively, and inflammatory markers [neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, neutrophil-to-platelet ratio (NPAR), CRP-to-albumin ratio (CAR), systemic inflammation index (SII), systemic inflammatory response index (SIRI) and pro-inflammatory index (PIV)] were calculated. Surgical evaluation (laparoscopy/laparotomy) provided histopathological confirmation of endometriosis. The 1996 revised American Society for Reproductive Medicine (rASRM) classification was used for staging. Statistical analyses used t-tests, Mann-Whitney U-tests, Chi-squared tests, Spearman's correlation, and linear regression modelling. p < 0.05 was considered to indicate significance.

Compared with controls, patients with endometriosis had lower white blood cell (7.28 vs 8.43 × 10³/mm³; p < 0.001), neutrophil (4.17 vs 5.09 × 10³/mm³; p < 0.001) and CRP (2.45 vs 3.34 mg/l; p = 0.008) levels, but higher haemoglobin (12.8 vs 11.9 g/dl; p = 0.001) and haematocrit (40.5 % vs 38.1 %; p < 0.001) levels. NPAR (1.38 vs 1.48; p < 0.001), SII (539 vs 737; p < 0.001), SIRI (1004 vs 1337; p < 0.001), PIV (302 vs 422; p < 0.001), CAR (0.061 vs 0.079; p = 0.008) and NLR (1.89 vs 2.44; p < 0.001) were also significantly lower in patients with endometriosis. Postoperatively, NLR, SIRI, PIV and NPAR increased (p < 0.05). Receiver operating characteristic curve analysis indicated moderate diagnostic performance for neutrophil percentage, NLR, SII, SIRI and PIV. On multi-variate analysis, bilaterality (p < 0.001) and area of endometriomas (p = 0.020) correlated with rASRM score.

Serum inflammatory markers reflect systemic immune changes in endometriosis. Although they offer diagnostic insights, lesion bilaterality and size remain stronger predictors of disease severity. Larger, multi-centre studies are needed to refine cut-off values and optimize clinical application of these markers.