[Procalcitonine--early marker of neonatal infection]

Neonatal infection represents the third most important cause of mortality in Neonatal Intensive Care Units (NICU), following perinatal asphyxia and respiratory distress syndrome. The incidence varies according to the level of care, between 5% in level II neonatal wards and 20% in the NICUs. The lack of specific early markers for infection could be partially responsible for the lack of antibiotic treatment or unnecessary treatment. In this context, many variables were examined as markers for sepsis. Large concentrations of C-reactive proteine (CRP) and procalcitonine (PCT) were positively correlated with the severity of the infection and generally indicated a poor outcome.

The aim of this study is to demonstrate the utility of PCT as a fast, early and routinely used marker of neonatal infection, correlated with CRP, clinical symptoms and blood cultures.

this is a retrospective-prospective study on 2 lots of newborns from two neonatal wards of different levels of care (Lot I - 32 newborns from the Cuza-Voda NICU in Iasi, born in 2010, Lot II - 127 newborns from the Buna Vestire Maternity in Galati, born during 2008-2009). PCT was assessed before the beginning of the antibiotic treatment in newborns with high risk of sepsis or newborns with proven sepsis as corroborated with complete blood counts, CRP, fibrinogen, clinical symptoms and blood cultures.

Among risk factors for neonatal infection, those found more often in newborns with proven sepsis are: ruptured membranes over 18 hours (p=0.043), Gram-negative bacilli colonization (p=0.003), respiratory distress syndrome (p=0.0008), abdominal distention (p=0.0042), oedema (p<<0.05) and necrotizing enterocolitis (p<<0.05). High values for PCT in premature newborns show the high risk for infection for this category of newborns, due to immunological imaturity and the presence of risk factors. High sensitivity and specificity of PCT (specificity =88.98%, sensitivity=87.5%) showed that the accuracy of PCT assessment in studied lots was 88.68% during the 24-72 hours of life time frame.

High serum levels of PCT in studied lots plead for the usage of PCT for the fast and early diagnostis of neonatal infection. In those cases with positive PCT and negative blood cultures or positive CRP and clinical symptoms of infection, PCT would be a useful tool, aiding in the initiation or termination of antibiotic treatment, which would ultimately lead to lowering costs. PCT as a screening tool for cases with risk factors for infection is still to be analysed in terms of costs versus benefits and the longterm implications of neonatal sepsis and antibiotic treatment.