RESUMO
UNLABELLED: Early diagnosis avoiding unnecessary treatment of maternal-fetal bacterial infection remains one of the greatest challenges for obstetricians and pediatricians. To meet these objectives, many inflammatory mediators were used, including procalcitonin (PCT). The aim of our study was to determine the usefulness of PCT in early diagnosis and management of neonatal infection. SUBJECTS AND METHODS: Over a period of 8 months, all living newborns with highly suspected maternal-fetal bacterial infection who were to receive antibiotic treatment according to our neonatal unit protocol were included in this prospective study. Serum PCT concentrations were determined at birth and after 12h of life using a specific immunoluminometric assay. Two distinct populations were defined based on clinical, biological, and bacteriological criteria: group 1: infected neonates, and group 2: noninfected neonates. STATISTICAL METHODS: We compared PCT means in different groups and determined the cut-off value correlated with maternal-fetal bacterial infection by analyzing the receiver operating characteristics curve (ROC). RESULTS: A total of 130 neonates were included in the study: 38 (29%) were classified in group 1 with 29 possible infections and 9 defined infections, including 5 cases of septicemia. The average PCT at birth in group 1 was significantly higher than in group 2 (3.52 ± 8.19 ng/ml vs 0.43 ± 0.73 ng/ml; P<0.001). The PCT threshold value at birth found by the ROC curve with the highest sensitivity (71.1%) and highest specificity (62%) was 0.215 ng/ml. The negative predictive value (NPV) was 83.8%, making it possible to avoid unnecessary treatment in the majority of the cases. The PCT threshold value within 12h of birth was 3.78 ng/ml, for a sensitivity of 89.5% and 1 NPV of 94.4%. CONCLUSION: PCT is a valuable biological examination because it can be administered early, it is sensitive, and it has a NPV. These characteristics make PCT a biological argument that can be used in the initial decision on whether to administer antibiotics. Another study will be conducted to establish the cut-off value.
