What are the cut-off levels for IL-6 and CRP in neonatal sepsis?

Positive maternal C-reactive protein predicts neonatal sepsis

PURPOSE

To evaluate the diagnostic performance of maternal inflammatory marker: C-reactive protein (CRP) in predicting early onset neonatal sepsis (that occurring within 72 hours after birth).

MATERIALS AND METHODS

126 low birth weight newborns (gestation 32±3.2 wk, birth weight 1887±623 g) and their mothers were included. Neonates were divided into sepsis group (n=51) including both proven (positive blood culture) and suspected (negative blood culture but with more than 3 abnormal clinical signs), and controls (n=75). Mothers were subgrouped into CRP positive ≥1.22 mg/dL (n=48) and CRP negative <1.22 mg/dL (n=78) group, determined by Receiver Operating Characteristic curves, and odds ratio was calculated for neonatal sepsis according to maternal condition.

RESULTS

Maternal CRP was significantly higher in neonatal sepsis group than in control (3.55±2.69 vs. 0.48±0.31 mg/dL, p=0.0001). Maternal CRP (cutoff value >1.22 mg/dL) had sensitivity 71% and specificity 84% for predicting neonatal sepsis. Maternal CRP positive group had more neonatal sepsis than CRP negative group (71% vs. 29%, p<0.001). Odds ratio of neonatal sepsis in maternal CRP positive group versus CRP negative group was 10.68 (95% confidence interval: 4.313-26.428, p<0.001).

CONCLUSION

The risk of early onset neonatal sepsis significantly increased in the case of positive maternal CRP (≥1.22 mg/dL). In newborn of CRP positive mother, the clinician may be alerted to earlier evaluation for possible neonatal infection prior to development of sepsis.

Saccharomyces boulardii for prevention of necrotizing enterocolitis in preterm infants: a randomized, controlled study

AIM

To evaluate the efficacy of orally administered Saccharomyces boulardii (S. boulardii) for reducing the incidence and severity of necrotizing enterocolitis (NEC) in very low-birth-weight (VLBW) infants.

METHODS

A prospective, randomised controlled trial was conducted in infants with gestational age ≤32 weeks and birth weight ≤1500 g. The study group received S. boulardii supplementation, and the control group did not. The primary outcomes were death or NEC (Bell's stage ≥2), and secondary outcomes were feeding intolerance and clinical or culture-proven sepsis.

RESULTS

A total of 271 infants were enrolled in the study, 135 in the study group and 136 in the control group. There was no significant difference in the incidence of death (3.7% vs. 3.6%, 95% CI of the difference, -5.20-5.25; p = 1.0) or NEC (4.4% vs. 5.1%, 95% CI, -0.65-5.12; p = 1.0) between the groups. However, feeding intolerance and clinical sepsis were significantly lower in the probiotic group compared with control.

CONCLUSION

Although Saccharomyces boulardii supplementation at a dose of 250 mg/day was not effective at reducing the incidence of death or NEC in VLBW infants, it improved feeding tolerance and reduced the risk of clinical sepsis.

C-reactive protein: a marker of neonatal stress?

AIM

To assess whether blood values of C-reactive protein (CRP) in healthy term newborns, are influenced by stress.

MATERIAL AND METHODS

Since different types of delivery (vaginal delivery [VD], emergency C-section [EMCS] and elective C-section [ELCS]) are notoriously characterized by different levels of stress for the baby, these three groups were used as models of different levels of stress. The mean CRP values of the three groups obtained in the first hours of life were compared.

RESULTS

We retrieved 1012 babies. Median values (3rd-97th ct) were: 0.05 (0.01-0.46), 0.17 (0.02-1.54), 0.30 (0.04-1.77), 0.43 (0.05-1.31), 0.40 (0.04-1.13) at 12, 24, 48, 72 and 96 h, respectively. Mean values in babies born after VD were statistically higher than those born after C-section, and higher CRP values were present in EMCS with respect to ELCS.

CONCLUSION

This study described normal blood CRP values in a wide population of term babies. An influence of the type of delivery on blood CRP is evident, and this may be explained by the different amount of perinatal stress induced by anyone of the three types of delivery we considered.

Mean platelet volume in neonatal sepsis

BACKGROUND

The aim of this study was to investigate any changes in mean platelet volume (MPV) in patients with neonatal sepsis (NS).

METHODS

Subjects were stratified into two groups: proven sepsis (Group 1a) and clinical sepsis (Group 1b). The control group (Group 2) consisted of healthy newborns matched for gestational age and birth weight.

RESULTS

A total of 100 patients with NS (35 with proven sepsis and 65 with clinical sepsis) and 50 healthy controls were enrolled. A comparison of markers of sepsis obtained at baseline revealed white blood cell count (WBC), C-reactive protein (CRP), interleukin-6 (IL-6), and MPV levels to be significantly higher in newborns with sepsis compared to healthy controls (P = 0.01, <0.001, <0.001, and 0.001, respectively). Mean baseline serum levels of CRP and MPV were significantly higher in Group 1a compared to Group 1b (P = 0.003, P = 0.007, respectively), whereas the difference between group with regards to baseline serum levels of IL-6 and platelet count was statistically insignificant (P = 0.14, P = 0.28, respectively).

CONCLUSION

This is the first study to demonstrate a statistically significant difference with regard to baseline MPV values between patients with sepsis (proven or clinical) and healthy controls.

Inflammatory responses to hepatitis B virus vaccine in healthy term infants

Hepatitis B virus (HBV) infection continues to be a serious global health problem. During the course of HBV vaccination, we observed C-reactive protein (CRP) elevation in term infants without sepsis. Therefore, we prospectively studied interleukin-6 (IL-6) and CRP responses to HBV immunization. In 70 healthy term infants without signs and symptoms of sepsis and sepsis risk factors, IL-6, CRP, and white blood cell count levels were determined before and 24 h after immunization. Significant increases in CRP levels were seen 24 h after vaccination (p < 0.001). Although CRP levels of 22 infants at second evaluation were above the cutoff level for sepsis (4.82 mg/L), they had no clinical signs and symptoms of sepsis. After 48-72 h, CRP levels of these infants returned to normal levels with no blood culture positivity.

CONCLUSION

our study showed that HBV vaccine is responsible for CRP elevation in term infants after vaccination at birth. To the best of our knowledge, this is the first study evaluating CRP response to HBV vaccine at birth in term infants. We suggest that this response should be considered in differentiation of early neonatal sepsis to avoid unnecessary antibiotic use.

The association of a cervical length of <25 mm in high-risk pregnancies on neonatal morbidity and mortality in preterm infants

PURPOSE

To evaluate and compare the effects of a short cervix (<25 mm) on neonatal morbidity and mortality as opposed to a normal cervical length (≥25 mm). The predictive value of a short cervix on neonatal outcome is also investigated.

METHODS

Preterm infants who were admitted to the neonatal intensive care unit and whose mothers had undergone a pre-delivery evaluation for cervical length (CL) and cervical cultures were included in the study. Infants were stratified into two groups based on CL measurements (Group 1, CL < 25 mm; Group 2, CL ≥ 25 mm).

RESULTS

A total of 203 infants were included in the final analysis. Group 1 consisted of 105 neonates while Group 2 had 98 newborns. Cervical culture positivity rate was 46.7 % (n = 49) in Group 1 compared to 19.4 % (n = 19) in Group 2 (p = 0.0001). Frequencies of early onset neonatal sepsis (EOS) in Group 1 and Group 2 were 31.5 and 18.4 %, respectively (p = 0.032), whereas respective frequencies of proven sepsis in the two groups were 18.1 and 8.2 % (p = 0.037). A CL < 25 mm was found to increase the risk of cervical culture positivity, EOS and proven EOS by odds ratios of 3.63, 2.03 and 2.48, respectively.

CONCLUSIONS

This is the first clinical study to demonstrate a significant link between CL and each of cervical culture positivity, EOS and neonatal morbidity and mortality. Preterm infants born to high-risk mothers with short CL should be monitored closely for the risk of EOS.

Serum ibuprofen levels of extremely preterm infants treated prophylactically with oral ibuprofen to prevent patent ductus arteriosus

AIM

The aim of this study was to explore the effects of early oral ibuprofen administration on the incidence of hemodynamically significant patent ductus arteriosus (hsPDA) and define the association between serum ibuprofen levels and ductal closure.

METHOD

Preterm infants with a gestational age of <28 weeks and/or birth weight of <1,000 g were randomized either to the intervention (ibuprofen prophylaxis) or control group. The intervention group received oral ibuprofen 10 mg/kg within 12-24 h after birth followed by 5 mg/kg at 24 and 48 h. Serum ibuprofen levels after the treatment were analyzed in the intervention group, and the incidence of hsPDA and complication rates were compared between two groups.

RESULTS

Nineteen infants who received one course (three doses) of prophylactic ibuprofen in the intervention group and 17 infants in the control group who underwent an echocardiographic examination on the fourth day of life were analyzed. hsPDA was observed in five (26 %) infants in the intervention group and ten (58 %) infants in the control group (p = 0.09). In the intervention group two infants experienced gastrointestinal bleeding two infants had spontaneous intestinal perforation, and two infants developed acute kidney failure. Mean serum ibuprofen level was 28.7 ± 16.9 mg/L in the intervention group, and there was no correlation between ibuprofen level obtained on the fourth day and ductal closure.

CONCLUSION

Oral ibuprofen prophylaxis reduces the rates of hsPDA even it is not statistically significant. The ductal closure rate did not correlate with serum ibuprofen levels. Due to high prevalence of adverse events observed, our data do not support the use of oral ibuprofen for prophylaxis of hsPDA.

Proadrenomedullin as a prognostic marker in neonatal sepsis

BACKGROUND

Proadrenomedullin (pro-ADM) for the diagnosis of proven and clinical sepsis in a newborn cohort including preterm newborns has not been investigated. We aimed to investigate the value of pro-ADM as a new marker by comparing it with conventional markers in neonatal sepsis (NS).

METHODS

Participants were stratified into three groups; proven sepsis (Group 1a), clinical sepsis (Group 1b), and the control group (Group 2), which consisted of newborns of matched gestational age and birth weight. Sequential measurements of white blood cell count, C-reactive protein (CRP), interleukin-6 (IL-6), and pro-ADM were compared.

RESULTS

A total of 76 patients with NS (31 with proven sepsis and 45 with clinical sepsis) and 52 healthy controls were enrolled. Mean baseline serum levels of CRP, IL-6, and pro-ADM were significantly higher in both Group 1a and Group 1b as compared with healthy controls (P < 0.001 for both). Although mean baseline CRP and IL-6 levels were similar between groups, mean baseline pro-ADM level was higher in the proven sepsis group than in the clinical sepsis group (P < 0.001).

CONCLUSION

The use of pro-ADM in combination with other acute-phase reactants such as CRP and IL-6 for the diagnosis and follow-up of patients with NS has high sensitivity and specificity.

Transfusion-associated necrotising enterocolitis in very low birth weight premature infants

OBJECTIVE

Our aim was to determine the relationship between red blood cell transfusion and necrotising enterocolitis (NEC) in all admitted very low birth weight (VLBW) infants with or without transfusion.

STUDY DESIGN

All VLBW neonates were categorised into five groups: (i) subjects that developed NEC <48 h after transfusion (n = 15); (ii) subjects that developed NEC >48 h after transfusion (n = 31); (iii) subjects that were never transfused but developed NEC, (n = 50); (iv) subjects that were transfused but did not develop NEC, (n = 250) and (v) subjects that were neither transfused nor developed NEC (n = 301).

RESULTS

A group of 647 infants were enrolled in the study. Mean gestational age and birth weight of the patients were 29 ± 3.1 weeks and 1157 ± 237 g, respectively. The mean age at the onset of NEC in the NEC groups were 20 ± 2.3 days, 12 ± 3 days and 11 ± 2.6 days, respectively (P < 0.05). The mean interval from the last transfusion to the onset of NEC was 16.8 ± 8.8 h in group 1 and 240 ± 50 h in group 2 (P < 0.05).

CONCLUSION

In this study, we sought to evaluate all VLBW infants, whether they received a transfusion or not. We suggest that transfusion associated NEC exists, but many other factors influence this multifactorial disease. The age of NEC onset was later in transfused vs non-transfused patients, whereas the interval between transfusion and NEC was shorter in transfused vs non-transfused patients.

Dose of intravenous lipids and rate of bacterial clearance in preterm infants with blood stream infections

BACKGROUND

Intravenous lipid emulsion (IVLE) is an integral part of the total parenteral nutrition (TPN) regimen in neonates. The use of IVLE during sepsis is the subject of controversy because it may interfere with phagocytosis of microbes by macrophages and may lead to significant hypertriglyceridemia.

OBJECTIVE

This paper aims to study the rate of clearance of bacteria in relation to dose of IVLE administered to preterm infants with blood stream infections (BSIs).

METHODS

Preterm infants (mean gestational age ± SD, 32.0 ± 2.5 weeks) with culture-proven BSI and receiving TPN were randomized to two groups. The first group (n = 22) was given the usual dose of IVLE according to a standard protocol (starting from 0.5 g kg(-1) day(-1) and gradually increased by 1 g kg(-1) day(-1) to a maximum of 3.5 g kg(-1) day(-1)); in the second group (n = 20), IVLE were restricted at a dose of 1 g kg(-1) day(-1). Samples for blood cultures were withdrawn every 24 h until a negative culture was obtained. CRP was measured daily until its normalization. Serum triglycerides were monitored daily.

RESULTS

The rate of bacterial clearance was significantly more rapid in the restricted-dose IVLE group compared to the standard-dose group [72 (48-120) versus 144 (72-168) h, p = 0.001]. Daily weight increment was significantly greater in the standard-dose IVLE group compared to the restricted-dose IVLE group [25 (6.9-31.9) versus 0.9 (-3.3-11.7) g, p = 0.0001]. The duration of antibiotic use was significantly reduced in the restricted-dose IVLE group compared with the standard-dose IVLE group (10.0 ± 4.5 vs 14.9 ± 5.1 days; p = 0.003). The durations of TPN, mechanical ventilation, and hospitalization were not significantly different between groups.

CONCLUSIONS

Restriction of the dose of IVLE to 1 g kg(-1) day(-1) in preterm infants with BSI is associated with earlier negative blood cultures and reduced duration of antibiotic therapy but was associated with a lower daily weight increments.

Cord blood interleukin-6 as a predictor of early-onset neonatal sepsis

AIM

To compare diagnostic accuracy in cord blood of interleukin-6 (IL-6) with C-reactive protein (CRP) as predictors of early-onset neonatal sepsis (EOS) in newborns with prenatal risk factors for infection.

METHODS

During 12 months, cord blood IL-6 and CRP were measured immediately after birth in neonates with prenatal risk factors of infection. The odds of developing sepsis based on IL-6 and CRP values were calculated using likelihood ratios (LR), and their accuracy as predictors was compared by binary logistic regression. Multivariable logistic regression analyses were performed to identify independent risk factors for sepsis.

RESULTS

Ten of 128 neonates (7.8%) were diagnosed with EOS confirmed with positive blood culture in five cases (3.9%). Cord blood IL-6 was a greater predictor of sepsis than CRP [ROC for IL-6 (0.88) vs. CRP (0.70)]. IL-6-positive and IL-6-negative LR [7.14 vs. -0.11] were superior to those calculated for CRP [2.86 vs. -0.51]. Chorioamnionitis and Apgar at 1 min were identified as independent risk factors for EOS.

CONCLUSIONS

Cord blood IL-6 showed superior LR than CRP; therefore, it is a better predictor to initiate treatment in neonates with prenatal infectious risk factors immediately after birth.

The effects of ibuprofen on sepsis parameters in preterm neonates

AIM

To examine the effects of ibuprofen used for patent ductus arteriosus (PDA) treatment on the production of the proinflammatory cytokines C-reactive protein (CRP) and interleukin 6 (IL-6) in preterm septic newborns.

METHODS

Patients with acute phase reactant elevation were divided into two groups according to receiving ibuprofen (Group I, n=51) or not (Group II, n=38). Course of sepsis was evaluated by CRP and IL-6 levels.

RESULTS

CRP and IL-6 levels at the time of diagnosis were not different between two groups [16±9.1 vs 16.4±13.2mg/dL (p=0.43) for CRP and 124±82 vs 119±73mg/dL (p=0.517) for IL-6, respectively]. Similarly, they were statistically insignificant between the groups at the 2nd or 3rd days of ibuprofen treatment [14.3±7.7 vs 13.7±5.9mg/dL (p=0.21) for CRP and 83±46 vs 86±37mg/dL (p=0.29) for IL-6, respectively]. However, CRP and IL6 levels showed significant difference between groups in the following days; 6.03±3.8 vs 9.1±4.9mg/dL (p=0.025) for CRP and 42±33.1 vs 58.9±27.1mg/dL (0.011) for IL-6 on 4th or 5th days of treatment and 2.3±3.2 vs 4.1±2.3mg/dL (p=0.032) for CRP and 16.1±12.4 vs 21.3±16.8mg/dL (p=0.016) for IL-6, on 7th to 10th days of treatment, respectively.

CONCLUSIONS

IL-6 and CRP may decrease in infants receiving ibuprofen treatment more than infants who do not receive it. This decrease should be considered at the time of caring a preterm infant with both sepsis and PDA after ibuprofen treatment.

Early inflammatory markers for prediction of cholestasis in very-low-birth-weight infants

BACKGROUND

Neonatal cholestasis is associated with increased mortality and other adverse outcomes. There are no tools for prediction of infants at risk for cholestasis.

OBJECTIVE

To determine if cholestasis in very-low-birth-weight (VLBW) infants is associated with alterations in cytokines or C-reactive protein (CRP) and, if so, whether inflammatory markers predict which infants will develop cholestasis.

METHODS

VLBW infants expected to be on parenteral nutrition for >7 days were enrolled in this prospective cohort study. Infants with direct bilirubin ≥1.0 mg/dl were considered to have a high risk for cholestasis and were compared to infants who never developed direct bilirubin ≥1.0 mg/dl. Standard descriptive statistics were used to compare biomarkers over time. Multivariable models were used to estimate associations between early inflammatory markers and cholestasis.

RESULTS

Of 63 infants enrolled, 29 were at risk for cholestasis. CRP was highly correlated with direct bilirubin. Infants in the high-risk group had significantly higher IL-1β, IL-6, IL-8, and IL-10 at 2, 4, and 6 weeks and CRP at 2 and 6 weeks. In logistic models, CRP (OR = 4.97, p = 0.02) or IL-1β (OR = 1.11, p = 0.008) at 2 weeks of age was predictive of cholestasis. In linear mixed-effects models, CRP (p < 0.001) or IL-6 (p = 0.02) and IL-8 (p < 0.001) were predictive of cholestasis.

CONCLUSION

Elevated CRP and cytokines are associated with cholestasis in VLBW infants. These inflammatory markers are candidates for further research into the pathogenesis, prediction, and prevention of cholestasis.

Automated determination of neutrophil VCS parameters in diagnosis and treatment efficacy of neonatal sepsis

INTRODUCTION

The Coulter LH780 hematology analyzer can evaluate mean neutrophil volume (MNV), conductivity (MNC), scatter (MNS), and distribution width (DW). We sought to investigate the value of volume, conductivity, and scatter (VCS) parameters in diagnosis and treatment efficacy of neonatal sepsis.

RESULTS

We observed significant increases in MNV, volume distribution width (VDW), conductivity distribution width (CDW), and significant decreases in MNC and MNS in septic newborns. There were significant decreases in MNV, VDW, and CDW, whereas MNC and MNS increased at the end of the treatment. Gram-negative sepsis caused higher MNV and VDW than Gram-positive sepsis.

DISCUSSION

This is the largest reported study seeking to determine cutoff levels of neutrophil VCS parameters in diagnosis of sepsis, and the first study in the evaluation of treatment efficacy and the effects of sepsis onset time and birth weight. We suggest that neutrophil VCS parameters and their DWs are useful both for early diagnosis and evaluation of treatment efficacy in neonatal sepsis without requirement for any extra blood collection.

METHODS

Peripheral blood samples from 304 newborns, 206 in group I (76 proven and 130 clinical sepsis) and 98 in group II (control group), were studied on diagnosis, 3rd day, and at the end of the treatment.

[The role of infection in preterm birth]

Intrauterine infection could be responsible for 25% up to 40% of preterm births. This relationship was initially demonstrated using animal models, inducing their abortion by injecting bacteria or endotoxins. In human research, examination of amniocentesis fluid showed the anteriority of infection over labor induction, and the existence of a subclinical latency phase between these two phenomena. The ascending route is preponderant, and four stages can be distinguished: cervical and vaginal infection, chorio-decidual infection, intra-amniotic infection, fetal infection. The intrauterine infection is very frequent in case of early preterm birth (<30 WG). It is associated with an increase of neurological and pulmonary morbidity. Most commonly found bacterial species are mycoplasma species, but also Escherichia coli, Gardnerella vaginalis and streptococcus B. Several markers of the infection have been studied: a maternal leukocytosis>15,000/mm(3) or a C-Reactive Protein (CRP)>20mg/l, an increase of fibronectin and/or IL-6 cervical, a short cervical length especially before 32 WG, a leukocytosis of the amniotic fluid, and/or high interleukin concentrations. The main marker used for the newborn is the CRP, but other markers can also be used for an early diagnosis of an infection, especially interleukin 6.