To investigate the clinical significance of ferritin (SF) in the diagnosis of neonatal early-onset sepsis.

Total of 109 cases of neonatal early-onset sepsis in neonatal intensive care unit (NICU) of Chengde Central Hospital were selected from August 2017 to August 2019, among whom, 54 cases (SF < 200 ng/ml) as SF normal group and 55 cases (SF ≥ 200 ng/ml) as SF elevated group. The general conditions (sex, onset day, gestational age, fetal heart abnormality or asphyxia, anemia in late pregnancy, full-term/preterm delivery, mode of delivery, premature rupture of membranes), inflammatory indicators levels such as C-reactive protein (CRP) and procalcitonin (PCT) were compared. Multivariate Logistic regression analysis was used to analyze the risk factors of elevated SF in early-onset sepsis. The changes of inflammatory indexes and their predictive value in the groups of newborns were compared by the ROC curves of CRP and PCT to predict ferritin level.

There were no significant differences in sex, abnormal fetal heart or asphyxia, anemia in late pregnancy, age of onset and age of pregnant mother between the two groups (all P > 0.05). But the delivery mode (χ² = 13.799, P < 0.001), full-term/preterm delivery (χ² = 10.717, P = 0.001) and premature rupture of membranes (χ² = 10.639, P = 0.001) were significantly different between the two groups. The levels of CRP [(5.43 ± 4.75) mg/L] and PCT [(5.85 ± 3.56) ng/ml] of neonates in SF normal group were significantly lower than those of SF elevated group [CRP: (13.79 ± 4.36) mg/L, PCT: (13.58 ± 7.42) ng/ml], with significant differences (t = 2.890, P = 0.006; t = 2.158, P = 0.034). Multivariate Logistic regression analysis showed that spontaneous delivery (OR = 5.16, P = 0.032), premature rupture of membranes (OR = 0.195, P = 0.038) and full-term (OR = 4.104, P = 0.041) were all independent risk factors for elevated SF in children with early-onset sepsis. The ROC curve of CRP and PCT to predict the increase of ferritin showed that: the best diagnostic cut-off point of CRP was > 10.4 mg/L, the sensitivity and specificity were 56.0% and 87.6%, respectively. The best diagnostic cut-off point of PCT was > 5.54 ng/ml, the sensitivity and specificity were 73.5% and 62.6%, respectively.

Early delivery, premature rupture of membranes and full-term were all independent risk factors for elevated SF in children with early-onset sepsis. Elevated SF could be used as an inflammatory marker to assist the diagnosis of early-onset sepsis.