Analytical performance of C-reactive protein and Procalcitonin and Potential Impact on Patient Care

Abstract

Antibiotic stewardship plays an important role in minimising antibiotic resistance. Procalcitonin (PCT) and C-reactive protein (CRP) are blood biomarkers which may be measured to guide antibiotic initiation and cessation. Algorithms for antibiotic stewardship may incorporate specific PCT and CRP cut-off values for antibiotic related intervention. Published literature for PCT method comparisons and external quality assessment data suggest significant differences of measured concentrations exist between individual PCT and CRP methods. Therefore, ubiquitous use of specific PCT and CRP intervention thresholds may not be appropriate. This study aimed to show the impact of PCT and CRP assay variability on clinical guidance, patient intervention and antibiotic stewardship. 60 serum samples were analysed on five automated PCT immunoassays in singleton. 16 EQA samples were analysed for PCT and CRP to review bias of each method and method imprecision was assessed over seven consecutive days, analysing three samples per day in singleton. Results for PCT and CRP overall showed acceptable imprecision across four different concentrations, however mean values of the precision pools across all methods were significantly different (P

Date of Award	1 Aug 2023
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Paul Dark (Supervisor) & Katherine Hayden (Supervisor)