Furthermore, critical patients underwent a decrease in the expression on roughly a third (11 out of 30) of the proteins over-expressed in this group of subjects, which included ARNTL (− 2.29 FC), SP9 (− 4.82 FC), Hepatocyte growth factor (− 1.47 FC), Polycystic kidney disease and receptor for egg jelly-related protein (− 1.59 FC), Serotansferrin (− 1.14 FC), OAF (− 1.50 FC), Haptoglobin (− 1.24 FC), and a number of immunoglobulins as IGHG4, IGLV7-46, IGKC and IGHG2 (FCs from − 1.47 to − 2.43) (Table 2). This evidence concerns the gene SP9 and polycystic kidney disease.