Systemic immune-inflammation index to predict placenta accreta spectrum and its histological subtypes

In this study, we aimed to investigate the role of systemic immune-inflammation index (SII) and other inflammatory parameters in the diagnosis of placenta accreta spectrum (PAS) and its histological subtypes.

This retrospective case-control study included patients who underwent surgery for placenta previa (PP). Case group (patients with PAS) included pregnant women diagnosed with histologically confirmed PAS, whereas control group (patients with PP) included pregnant women who underwent cesarean section with a PP diagnosis, required no additional intervention during the operation. Both groups were compared with respect to their demographic data, clinical characteristics, SII, and other laboratory parameters. Cut-off values that can predict PAS were calculated. The PAS group was separated into subgroups based on histology findings, and inflammatory parameters were compared between subgroups.

In this study, data of 273 patients were analyzed. Of these, 68 (24.9%) were included in the PAS group and 205 (75.1%) patients were included in the PP group. Significant differences were observed in SII, platelet distribution width, mean platelet volume, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio (p = 0.000, p = 0.006, p = 0.002, p = 0.000, and p = 0.000, respectively). The best SII cut-off value was 985.02109/L (57.4% sensitivity and 72.2% specificity). There was no significant association between the histologic subtypes of PAS and inflammatory parameters.

SII can be used to predict PAS in pregnant women with PP. The relationship between the histologic subtypes of PAS and inflammatory parameters should be investigated in more comprehensive studies.