Calgranulin C is a natural immune peptide at the air–mucosal interface associated with neutrophil involvement, which, when overexpressed, has been implicated as a biomarker of inflammatory diseases. We hypothesized that S100A12 is differentially expressed in the sinonasal mucosa of patients with CRS than controls and that S100A12 is a potential biomarker of CRS-specific QOL and disease severity.

The present study was a prospective observational study, including 70 patients: 17 controls, 28 having CRSsNP, and 25 with CRSwNP. The expression of S100A12 and HNE was assessed in the anterior ethmoid tissues from all patients using ELISA and IHC analyses. Disease-specific QOL and disease severity were evaluated and correlated to the expression levels of S100A12.

S100A12 and HNE were significantly elevated in patients with CRSsNP than normal controls and patients with CRSwNP, as measured by ELISA and IHC analyses. Patients with CRS exhibited worse CRS-specific disease severity than standard rules, and the increased protein levels of S100A12 were significantly correlated to disease severity, represented by CT scores.

The study concluded that S100A12 is differentially expressed in CRS subtypes and is significantly elevated in patients with CRSsNP and associated with CRS-specific disease severity.