In a context so far rarely explored, this proteomics study on patients with postoperative peritoneal infection found a possible effect on serum proteins involved in oncological processes, inflammation and immune response, as well as pathways related to cardiomyopathy, extracellular matrix organisation, cell adhesion, PI3K-Akt and TGF-β. This evidence concerns the gene TGFB1 and cardiomyopathy.