Pancreatic Stone Protein in the Diagnosis of Sepsis in Children Admitted to High-Dependency Care: A Single-Center Prospective Cohort Study

Objectives: Blood level of pancreatic stone protein (PSP) is a promising biomarker of sepsis both in adults and children. The aim of our study was to investigate the diagnostic accuracy of PSP in children with suspected sepsis and to compare diagnostic performance with other sepsis biomarkers approved for clinical use, that is, procalcitonin (PCT) and C-reactive protein (CRP). Design: Prospective study. Setting: PICU and pediatric emergency department. Intervention: Blood levels of PSP were measured using a nanofluidic point-of-care immunoassay (abioSCOPE, Abionic SA, Switzerland) within 24 hours of admission. Measurements and main results: We studied 99 children aged between older than 1 month and younger than 18 years with signs and symptoms of systemic inflammatory response syndrome (irrespective of associated organ dysfunction). The prevalence of sepsis was 35 of 99 (35.4%). Patients with sepsis had higher PSP levels ( p < 0.001) than patients with systemic inflammation of noninfectious cause. In this analysis, the optimal cutoff for the diagnosis of sepsis using PSP was 123 ng/mL, which resulted in a sensitivity of 0.63 (95% CI, 0.43-0.80), specificity of 0.89 (95% CI, 0.77-0.95). The PSP test area under the receiver operating characteristic curve (AUROC) was 0.82 (95% CI, 0.73-0.91) and, by comparison, procalcitonin and CRP AUROC were 0.70 (95% CI, 0.58-0.82) and 0.72 (95% CI, 0.60-0.84), respectively. Overall, the pretest to posttest probability of sepsis with a positive test changed from 0.35 to 0.73. Conclusions: In this single-center prospective pediatric cohort, admitted to the high intensive care and to the PICU, our findings suggested the potential use of PSP as a sepsis biomarker. However, because of the clinical diagnostic uncertainty with a positive result, further investigation is needed particularly in combination with other biomarkers.