Serum procalcitonin as an early marker of neonatal sepsis.
BACKGROUND
It has recently been suggested that procalcitonin (PCT) is of value in the diagnosis of neonatal sepsis, with varying results. This study was to evaluate the role of PCT as a single early marker of neonatal sepsis.


METHODS
Neonatal Unit, Johannesburg Hospital, and Microbiology Laboratory, National Health Laboratory Service (NHLS), South Africa.


METHODS
Neonates undergoing evaluation for sepsis between April and August 2002 were eligible for inclusion. Patients were categorised into 'no infection', 'possible infection' and 'definite infection' on the basis of C-reactive protein (CRP), white cell count (WCC), platelet count and blood culture results. PCT was correlated with infection categories.


RESULTS
One hundred and eighty-three neonates were enrolled. One hundred and eighteen had no infection, 52 possible infection and 13 definite infection. PCT differed significantly among infection categories (p < 0.0001) and correlated significantly with CRP at presentation (correlation coefficient 0.404, p < 0.001) and CRP at 24 hours (correlation coefficient 0.343, p < 0.001). PCT predicted 89.5% of definite infection. Receiver operating characteristic (ROC) analysis for PCT to predict definite infection showed odds ratio (OR) 1.145 (95% confidence interval (CI): 1.05-1.25) with an area under the curve of 0.778. PCT had a negative predictive value of 0.95 (95% CI: 0.915-0.988) for definite infection.


CONCLUSIONS
Although PCT was significantly related to the category of infection, it is not sufficiently reliable to be the sole marker of neonatal sepsis. PCT would be useful as part of a full sepsis evaluation, but is relatively expensive. A negative PCT on presentation may rule out sepsis, but this needs to be evaluated further.
Ballot
Daynia E
DE
Department of Paediatrics, University of the Witwatersrand, Johannesburg.
Perovic
Olga
O
Galpin
Jacky
J
Cooper
Peter A
PA
D016470:Bacteremia / Q000175:diagnosis / Q000382:microbiology; D015415:Biomarkers / Q000097:blood; D001724:Birth Weight; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D016015:Logistic Models; D010976:Platelet Count; D011237:Predictive Value of Tests; D011498:Protein Precursors / Q000097:blood*; D012372:ROC Curve; D018805:Sepsis / Q000097:blood* / Q000175:diagnosis*
D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide