Serum expression of ESM-1 and Syndecan-1 and its relationship with disease severity in children with Mycoplasma pneumoniae pneumonia.

Background: This study aim to investigate the role of endothelial damage in the pathogenesis of Mycoplasma pneumoniae pneumonia (MPP) by comparing serum levels of endothelial cell-specific molecule 1 (ESM-1) and Syndecan-1 in patients with varying degrees of MPP severity. Additionally, we aim to explore the relationship between the production of ESM-1 and Syndecan-1 and the severity of MPP, inflammation, as well as hypercoagulative state in children.

Methods: A prospective, observational study that included clinical manifestations, laboratory tests, and serum ESM-1 and Syndecan-1 assays. The correlation between ESM-1 and Syndecan-1 levels with inflammatory markers and coagulation markers was analyzed. Multivariate logistic regression analysis was conducted to identify significant risk factors for Severe Mycoplasma pneumoniae pneumonia (SMPP).

Results: A total of 179 children with MPP and 40 healthy volunteers were enrolled. Serum ESM-1 and Syndecan-1 levels were significantly elevated in children with MPP compared to the healthy children (all P < 0.05). A multivariate analysis revealed that ESM-1, Syndecan-1, D-dimer and LDH were the significant predictors of SMPP, with odds ratios of 1.034, 1.002, 5.042 and 1.014, respectively. The optimal cutoff values of ESM-1, Syndecan-1, D-dimer and LDH for predicting SMPP were 79.67 ng/mL, 3219.35 pg/mL, 0.67 µg/mL and 365.00 U/L, respectively.

Conclusions: ESM-1, Syndecan-1, D-dimer, and LDH can serve as independent predictors for SMPP. The interaction between endothelial damage, excessive inflammatory response, and hypercoagulable state collectively contributes to the development and progression of SMPP.