Assessing current c-reactive protein sampling practices within the neonatal intensive care unit for neonates with suspected early onset sepsis

Abstract

C-reactive protein is synthesized in the liver as part of the acute phase response activated in reaction to acute injury. It has been well established that CRP levels can be used as an acute marker of inflammation making it a useful aid in the diagnosis and management of sepsis. However, its use within the immediate postnatal period presents unique challenges. Aim: This study aimed to elucidate and standardise CRP blood sampling intervals in neonates with suspected early onset sepsis, and to describe the relationship between CRP results and final blood culture results, with the aim of implementing NICE recommendations within the local setting. Results: 316 infants were included in the study. 26.2% of neonates had at least 1 positive CRP value (>10 mg/dl) during the first 72 hours of life, with 12.7% resulting in a detectable bacterial growth on blood cultures. The largest percentage of positive CRP levels was obtained when blood was sampled within 18 to 24 hours post birth (30.3%). 40.7% of CRP samples were repeated between 24-48 hours of life. For 27.7% of neonates, a first positive CRP level of more than 10 mg/dl was noted after 24 hours of life. The results show the importance of maintaining adequate timing intervals between serial CRP levels, which should be taken as a baseline on admission and then repeated not before 12 hours of age, to achieve optimal sensitivity. Our current sampling practice might lead to falsely reassuring negative CRP values, affecting outcomes in sepsis management.