Trends in the incidence and associated factors of late-onset sepsis associated with improved survival in extremely preterm infants born at 23-26 weeks' gestation: a retrospective study

Late-Onset Sepsis among Extremely Preterm Infants of 24-28 Weeks Gestation: An International Comparison in 10 High-Income Countries

INTRODUCTION

Despite advances in neonatal care, late-onset sepsis remains an important cause of preventable morbidity and mortality. Neonatal late-onset sepsis rates have decreased in some countries, while in others they have not. Our objective was to compare trends in late-onset sepsis rates in 9 population-based networks from 10 countries and to assess the associated mortality within 7 days of late-onset sepsis.

METHODS

We performed a retrospective population-based cohort study. Infants born at 24-28 weeks' gestation between 2007 and 2019 were eligible for inclusion. Late-onset sepsis was defined as a positive blood or cerebrospinal fluid culture. Late-onset sepsis rates were calculated for 3 epochs (2007-11, 2012-15, and 2016-19). Adjusted risk ratios (aRRs) for late-onset sepsis were calculated for each network.

RESULTS

Of a total of 82,850 infants, 16,914 (20.4%) had late-onset sepsis, with Japan having the lowest rate (7.1%) and Spain the highest (44.6%). Late-onset sepsis rates decreased in most networks and remained unchanged in a few. Israel, Sweden, and Finland showed the largest decrease in late-onset sepsis rates. The aRRs for late-onset sepsis showed wide variations between networks. The rate of mortality temporally related to late-onset sepsis was 10.9%. The adjusted mean length of stay for infants with late-onset sepsis was increased by 5-18 days compared to infants with no late-onset sepsis.

CONCLUSIONS

One in 5 neonates of 24-28 weeks' gestation develops late-onset sepsis. Wide variability in late-onset sepsis rates exists between networks with most networks exhibiting improvement. Late-onset sepsis was associated with increased mortality and length of stay.

Late-Onset Sepsis in Very Low Birth Weight Infants

BACKGROUND AND OBJECTIVES

Late-onset sepsis is associated with significant morbidity and mortality among very low birth weight (VLBW) infants. Our objective was to determine risk factors associated with late-onset sepsis and to present temporal trends in overall and pathogen-specific rates.

METHODS

Population-based study by the Israel Neonatal Network on VLBW infants (≤1500 g) born between 1995 and 2019. Late-onset sepsis required clinical symptoms and microbiologic confirmation. Bivariate and multivariable analyses were performed to identify risk factors. The study period was divided into 4 epochs. Overall and pathogen-specific late-onset sepsis rates for each epoch were compared.

RESULTS

The study population comprised 31 612 VLBW infants, of whom 7423 (23.5%) had late-onset sepsis. An increased adjusted risk of late-onset sepsis was associated with gestational age <27 w (odds ratio [OR] 8.90, 95% confidence interval [CI] 7.85-10.09) and delivery room resuscitation (OR 1.43, 95% CI 1.34-1.52) and a decreased adjusted risk among infants born between 2013 and 2019 (OR 0.32, 95% CI 0.29-0.35). Late-onset sepsis rates declined from 29.5% in 1995 to 2000 to 13.0% in 2013 to 2019. Gram-negative and fungal rates decreased in all epochs, whereas gram-positive rates decreased only in the last epoch. The adjusted hazard ratios (95% CI) decreased in the 2013 to 2019 versus 1995 to 2000 epochs and were: all late-onset sepsis, 0.40 (0.37-0.43); gram-positive, 0.47 (0.37-0.59); gram- negative, 0.54 (0.48-0.61); fungal, 0.17 (0.12-0.22).

CONCLUSIONS

The strongest risk factor for late-onset sepsis was gestational age <27 w. Over a 25-year period, the pathogen-specific rates of late-onset sepsis among VLBW infants decreased approximately twofold for gram-positive and gram-negative bacterial infections and sixfold for fungal infections.

Neonatal sepsis-causing bacterial pathogens and outcome of trends of their antimicrobial susceptibility a 20-year period at a neonatal intensive care unit

BACKGROUND

Due to increases in the number of infants born with younger gestational age (GA) and lower birth weight, the incidence of neonatal sepsis is increasing.

PURPOSE

We investigated the changes in the prevalence of bacterial pathogens, their antimicrobial susceptibility, and sepsis-related mortality during 20 years at a neonatal intensive care unit.

METHODS

The study period was divided into two 10-year phases (1998-2007 vs. 2008-2017). Medical records were reviewed to gather data on demographics, causative microbial pathogens, incidence of multidrug-resistant organisms, antimicrobial susceptibility, and rates of sepsis-related mortality.

RESULTS

In both study phases, the most common pathogens for neonatal sepsis were coagulase-negative Staphylococcus (CoNS) (28.6%) and Enterobacter cloacae (16.1%) for early-onset sepsis (EOS, ≤72 hours after birth) and CoNS (54.7%) and Staphylococcus aureus (12.9%) for late-onset sepsis (LOS, >72 hours after birth). CoNS and S. aureus showed 100% sensitivity to vancomycin in both phases. The susceptibility of S. aureus to oxacillin increased from 19.2% to 57.9% in phase II than phase I. K. pneumonia and E. cloacae showed increases in its susceptibility to gentamicin, cefotaxime and ceftriaxone in phase II than phase I. In both phases, the most common pathogens that caused sepsis-related death were K. pneumoniae (18.2%) and Pseudomonas aeruginosa (13.6%). Sepsis-related mortality rate was higher in infants with GA <37 weeks than those with GA over 37 weeks (P=0.016). In addition, the mortality rate of neonatal sepsis caused by gram-negative bacteria was significantly higher than that caused by gram-positive bacteria (P<0.001).

CONCLUSIONS

CoNS was the most common pathogen for EOS and LOS. While we found significant changes in antimicrobial sensitivities over time. GA below 37 weeks and gram-negative organisms are associated with mortality rate.

Effect of levothyroxine supplementation in extremely low birth weight infants with transient hypothyroxinemia of prematurity

This study aimed to determine the short- and/or long-term outcomes of levothyroxine replacement therapy in extremely low birth weight (ELBW) infants with transient hypothyroxinemia of prematurity (THOP). The medical records of 335 ELBW infants with THOP were reviewed retrospectively to identify whether levothyroxine treatment affects short- and/or long-term outcomes at a corrected age of 2 years. The infants were arbitrarily grouped based on thyroxine (T4) (free T4 [fT4]) levels into group 1 (n = 142), which included infants with T4 (fT4) levels < 2.5 (0.5) ng/dl, and group 2 (n = 193), which included those with T4 (fT4) levels ranging from ≥ 2.5 (0.5) ng/dl to < 4.5 (0.9) ng/dl. Levothyroxine replacement therapy was not associated with beneficial short- or long-term outcomes in ELBW infants with THOP. Short-term outcomes, such as mortality and composite morbidities, and long-term outcomes, such as failure to achieve catch-up height at a corrected age of 2 years, were significantly higher in group 1 than in group 2, regardless of levothyroxine treatment status. Levothyroxine replacement therapy is not associated with short-or long-term advantages in ELBW infants with THOP. This study suggests that the severity of THOP may be the major determinant of adverse outcomes in ELBW infants with THOP, rather than levothyroxine treatment.

Contemporary Trends in Global Mortality of Sepsis Among Young Infants Less Than 90 Days: A Systematic Review and Meta-Analysis

Objective

Current knowledge on the global burden of infant sepsis is limited to population-level data. We aimed to summarize global case fatality rates (CFRs) of young infants with sepsis, stratified by gross national income (GNI) status and patient-level risk factors.

Methods

We performed a systematic review and meta-analysis on CFRs among young infants < 90 days with sepsis. We searched PubMed, Cochrane Central, Embase, and Web of Science for studies published between January 2010 and September 2019. We obtained pooled CFRs estimates using the random effects model. We performed a univariate analysis at patient-level and a meta-regression to study the associations of gestational age, birth weight, onset of sepsis, GNI, age group and culture-proven sepsis with CFRs.

Results

The search yielded 6314 publications, of which 240 studies (N = 437,796 patients) from 77 countries were included. Of 240 studies, 99 were conducted in high-income countries, 44 in upper-middle-income countries, 82 in lower-middle-income countries, 6 in low-income countries and 9 in multiple income-level countries. Overall pooled CFR was 18% (95% CI, 17-19%). The CFR was highest for low-income countries [25% (95% CI, 7-43%)], followed by lower-middle [25% (95% CI, 7-43%)], upper-middle [21% (95% CI, 18-24%)] and lowest for high-income countries [12% (95% CI, 11-13%)]. Factors associated with high CFRs included prematurity, low birth weight, age less than 28 days, early onset sepsis, hospital acquired infections and sepsis in middle- and low-income countries. Study setting in middle-income countries was an independent predictor of high CFRs. We found a widening disparity in CFRs between countries of different GNI over time.

Conclusion

Young infant sepsis remains a major global health challenge. The widening disparity in young infant sepsis CFRs between GNI groups underscore the need to channel greater resources especially to the lower income regions.

Systematic Review Registration

[www.crd.york.ac.uk/prospero], identifier [CRD42020164321].

Determinants of late neonatal nosocomial infection: a case-control study in Ceará

OBJECTIVES

To assess the determining factors of late healthcare-associated infections (HAIs) and bacterial multiple drug resistance in neonatal intensive care.

METHODS

This is a case-control study, conducted between January 2013 and December 2017, in a neonatal intensive care unit in the state of Ceará, Brazil. Newborns showing late HAIs were considered cases and those without infection, the control. Variables with p-values ≤ 0.05 in our initial bivariate regressive analysis were included in a non-conditional hierarchical logistic model for multivariate analysis. P-values below 0.01 were considered significant.

RESULTS

Of the 1,132 participants, 427 (37.7%) showed late healthcare-associated infections. Of these, 54 (12.6%), positive blood cultures, of which 14.9% contained multidrug-resistant bacteria. Bivariate analysis showed the protective effect of the feminine phenotype (OR = 0.71; 95%CI: 0.56-0.90) and of gestational ages ≥ 34 weeks (OR = 0.48; 95%CI: 0.30-0.75). In earlier-born preterm infants, late infections were 18 times more likely in those with less than 30 week-gestations (OR = 18.61; 95%CI: 9.84-35.22) and four times higher in those weighing less than 1,500 g (OR = 4.18; 95%CI: 3.12-5.61). Mechanical ventilation increased infection odds by more than seven times (OR = 7.14; 95%CI: 5.26-9.09); as did parenteral nutrition (OR = 5.88; 95%CI: 4.54-7.69); central venous catheters (OR = 10.00; 95%CI: 6.66-16.66); the number of catheters used (OR = 3.93; 95%CI: 3.02-5.12); surgery (OR = 4.00; 95%CI: 2.27-7.14); and hospitalization time (OR = 1.06; 95%CI: 1.05-1.07). The association between preterm infants with less than 30 week-gestations (OR = 5.62; 95%CI: 1.83-17.28); mechanical ventilation (OR = 1.84; 95%CI: 1.26-2.68); central venous catheters (OR = 2.48; 95%CI: 1.40-4.37); and hospitalization time (OR = 1.06; 95%CI: 1.05-1.07) remained significant after adjustment. Among deaths, 41 (55.4%) were associated with late infections.

CONCLUSION

Better practices should be adopted in caring for the premature, as well as in the rational use of procedures, to avoid late healthcare-associated infections, preventable deaths, and risks of bacterial multiple drug resistance and environmental contamination.

Cesarean section was not associated with mortality or morbidities advantage in very low birth weight infants: a nationwide cohort study

This study investigated the role of cesarean section (CS) in mortality and morbidity of very-low-birth-weight infants (VLBWIs) weighing less than 1500 g. This nationwide prospective cohort study of the Korean Neonatal Network consisted of 9,286 VLBWIs at 23–34 gestational weeks (GW) of age between 2013 and 2017. The VLBWIs were stratified into 23–24, 25–26, 27–28 and 29–34 GW, and the mortality and morbidity were compared according to the mode of delivery. The total CS rate was 78%, and was directly proportional to gestational age. The CS rate was the lowest at 61% in case of infants born at 23–24 GW and the highest at 84% in VLBWIs delivered at 29–34 GW. Contrary to the significantly lower total mortality (12%) and morbidities including sepsis (21%) associated with CS than vaginal delivery (VD) (16% and 24%, respectively), the mortality in the 25–26 GW (26%) and sepsis in the 27–28 GW (25%) and 29–34 GW (12%) groups were significantly higher in CS than in VD (21%, 20% and 8%, respectively). In multivariate analyses, the adjusted odds ratios (ORs) for mortality (OR 1.06, 95% CI 0.89–1.25) and morbidity including sepsis (OR 1.12, 95% CI 0.98–1.27) were not significantly reduced with CS compared with VD. The adjusted ORs for respiratory distress syndrome (1.89, 95% CI 1.59–2.23) and symptomatic patent ductus arteriosus (1.21, 95% CI 1.08–1.37) were significantly increased with CS than VD. In summary, CS was not associated with any survival or morbidity advantage in VLBWIs. These findings indicate that routine CS in VLBWIs without obstetric indications is contraindicated.

Stem cells for bronchopulmonary dysplasia in preterm infants: A randomized controlled phase II trial

We previously demonstrated the safety and feasibility of mesenchymal stem cell (MSC) transplantation for bronchopulmonary dysplasia (BPD) in preterm infants in a phase I clinical trial. We thus investigated the therapeutic efficacy of MSCs for BPD in premature infants. A phase II double-blind, randomized, placebo-controlled clinical trial was conducted on preterm infants at 23 to 28 gestational weeks (GW) receiving mechanical ventilator support with respiratory deterioration between postnatal days 5 and 14. Infants were stratified by 23 to 24 GW and 25 to 28 GW and randomly allocated (1:1) to receive stem cells (1 × 10⁷ cells/kg, n = 33) or placebo (n = 33). Although the inflammatory cytokines in the tracheal aspirate fluid were significantly reduced with MSCs, the primary outcome of death or severe/moderate BPD in the control group (18/33, 55%) was not significantly improved with MSC transplantation (17/33, 52%). In the subgroup analysis, the secondary outcome of severe BPD was significantly improved from 53% (8/15) to 19% (3/16) with MSC transplantation in the 23 to 24 GW group but not in the 25 to 28 GW subgroup. In summary, although MSC transplantation might be safe and feasible, this small study was underpowered to detect its therapeutic efficacy in preterm infants at 23 to 28 GW. Accordingly, we are now conducting an additional larger and controlled phase II clinical trial focusing on infants at 23 to 24 GW (NCT03392467). ClinicalTrials.gov identifier: NCT01828957.

Fetal inflammation induces acute immune tolerance in the neonatal rat hippocampus

BACKGROUND

Infants born preterm due to chorioamnionitis are frequently affected by a fetal inflammatory response syndrome (FIRS) and then by subsequent postnatal infections. FIRS and postnatal systemic inflammatory events independently contribute to poor neurocognitive outcomes of preterm infants. Developmental integrity of the hippocampus is crucial for intact neurocognitive outcomes in preterms and hippocampally dependent behaviors are particularly vulnerable to preterm systemic inflammation. How FIRS modulates the hippocampal immune response to acute postnatal inflammatory events is not well understood.

METHODS

Prenatal LPS exposed (FIRS) and control neonatal rats received i.p. LPS or saline at postnatal day (P) 5. On P7, immune response was evaluated in the hippocampus of four treatment groups by measuring gene expression of inflammatory mediators and cytosolic and nuclear NFκB pathway proteins. Microglial activation was determined by CD11b+ and Iba1+ immunohistochemistry (IHC) and inflammatory gene expression of isolated microglia. Astrocyte reactivity was measured using Gfap+ IHC.

RESULTS

Postnatal LPS resulted in a robust hippocampal inflammatory response. In contrast, FIRS induced by prenatal LPS attenuated the response to postnatal LPS exposure, evidenced by decreased gene expression of inflammatory mediators, decreased nuclear NFκB p65 protein, and fewer activated CD11b+ and Iba1+ microglia. Isolated microglia demonstrated inflammatory gene upregulation to postnatal LPS without evidence of immune tolerance by prenatal LPS.

CONCLUSION

Prenatal LPS exposure induced immune tolerance to subsequent postnatal LPS exposure in the hippocampus. Microglia demonstrate a robust inflammatory response to postnatal LPS, but only a partial immune tolerance response.

Diagnosis of Neonatal Late-Onset Infection in Very Preterm Infant: Inter-Observer Agreement and International Classifications

Background: The definition of late-onset bacterial sepsis (LOS) in very preterm infants is not unified. The objective was to assess the concordance of LOS diagnosis between experts in neonatal infection and international classifications and to evaluate the potential impact on heart rate variability and rate of “bronchopulmonary dysplasia or death”. Methods: A retrospective (2017–2020) multicenter study including hospitalized infants born before 31 weeks of gestation with intention to treat at least 5-days with antibiotics was performed. LOS was classified as “certain or probable” or “doubtful” independently by five experts and according to four international classifications with concordance assessed by Fleiss’s kappa test. Results: LOS was suspected at seven days (IQR: 5–11) of life in 48 infants. Following expert classification, 36 of them (75%) were considered as “certain or probable” (kappa = 0.41). Following international classification, this number varied from 13 to 46 (kappa = −0.08). Using the expert classification, “bronchopulmonary dysplasia or death” occurred less frequently in the doubtful group (25% vs. 78%, p < 0.001). Differences existed in HRV changes between the two groups. Conclusion: The definition of LOS is not consensual with a low international and moderate inter-observer agreement. This affects the evaluation of associated organ dysfunction and prognosis.

Survival rate dependent variations in retinopathy of prematurity treatment rates in very low birth weight infants

As increased oxidative stress causes increased mortality and morbidities like bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) in very low birth weight infants (VLBWIs), the conundrum of improved survival but increased ROP observed with the high oxygen saturation target range of 91–95% is difficult to explain. To determine the survival rate-dependent variation in ROP treatment rate, 6292 surviving eligible VLBWIs registered in the Korean Neonatal Network were arbitrarily grouped according to the survival rate of infants at 23–24 weeks’ gestation as group I (> 70%, n = 1626), group II (40–70%, n = 2984) and group III (< 40%, n = 1682). Despite significantly higher survival and lower BPD rates in group I than in groups II and III, the ROP treatment rate was higher in group I than in groups II and III. However, the adjusted odds ratios for ROP treatment were not significantly different between the study groups, and the ROP treatment rate in the infants at 23–24 weeks’ gestation was 21-fold higher than the infants at ≥ 27 weeks’ gestation. The controversial association between improved survival and reduced BPD reflecting quality improvement of neonatal intensive care but increased ROP treatment rate might be primarily attributed to the improved survival of the most immature infants.

Neonatal Sepsis and Its Associated Factors Among Neonates Admitted to Neonatal Intensive Care Units in Primary Hospitals in Central Gondar Zone, Northwest Ethiopia, 2019

BACKGROUND

Neonatal sepsis contributes substantially to neonatal morbidity and mortality and is an ongoing major global public health challenge particularly in developing countries. Studies conducted on the proportion and risk factors of neonatal sepsis in Ethiopia are from referral hospitals, which may not be generalized to primary health care units where a significant proportion of mothers give birth in these health facilities. This study sought to determine the proportion of clinical neonatal sepsis and associated factors in the study areas.

METHODS

Institutional-based cross-sectional study was conducted from March to April 2019, in Amhara regional state, central Gondar zone public primary hospitals in Ethiopia. A total of 352 subjects (mother-neonate pairs) were selected using a systematic random sampling technique and pre-tested and structured questionnaires were used to collect data. Multivariable logistic regression analysis was fitted to identify factors associated with neonatal sepsis. Adjusted odds ratio (AOR) with the corresponding 95% confidence interval (CI) was used to show the strength of associations and variables with p-values of <0.05 were considered as statistically significant.

RESULTS

The overall proportion of neonatal sepsis was 64.8% (95% CI (59.2, 69.2)). Being male neonate (AOR=3.7; 95% CI (1.76, 7.89)), history of urinary tract infections during the index pregnancy (AOR =6, 26; 95% CI (1.16, 33.62)), frequency of per-vaginal examination greater than three during labor and delivery (AOR=6.06; 95% CI (2.45, 14.99)), neonatal resuscitation at birth (AOR=6.1; 95% CI (1.71, 21.84)), place of delivery at the health center (AOR=3.05; 95% CI (1.19, 7.79)), lack of training of health workers on neonatal resuscitation and infection prevention practices (AOR=2.14; 95% CI (1.04, 4.44)), late age of neonate at onset of illness (AOR=0.05; 95% CI (0.01, 0.21)) and maternal age of 30-34 years (AOR=0.19; 95% CI (0.047, 0.81)) were significantly associated with neonatal sepsis.

CONCLUSION

The proportion of neonatal sepsis is high. Maternal, neonatal, and health service related factors were identified for neonatal sepsis. Therefore, training of health workers, provision of health care services as per standards, and monitoring and evaluation of obstetrical/neonatal care during labor and delivery are mandatory.

Mortality rate-dependent variations in antenatal corticosteroid-associated outcomes in very low birth weight infants with 23-34 weeks of gestation: A nationwide cohort study

Antenatal corticosteroid (ACS) administration has been known as one of the most effective treatment in perinatal medicine, but the beneficial effects of ACS may vary not only gestational age, but also the quality of perinatal and neonatal care of the institution. This nationwide cohort study of the Korean Neonatal Network (KNN) data was consisted of <1,500g infants born at 23–34 weeks at 67 KNN hospitals between 2013 and 2017. The 9,142 eligible infants were assigned into two groups–group 1 and 2 <50% and ≥50% mortality rate, respectively, for 23–24 weeks’ gestation–reflecting the quality of perinatal and neonatal care. Each group of infants were further stratified into 23–24, 25–26, 27–28, and 29–34 weeks of gestation age. Despite comparable ACS usage between group 1 (82%) and group 2 (81%), the benefits of ACS were only observed in group 1. In the multivariable analyses, infants of group 1 showed significant decrease in mortality and IVH at gestational age 23–24 weeks with ACS use, and the decrease was also seen in early-onset sepsis and respiratory distress syndrome at gestational age of 29–34 weeks while there were no significant decrease in group 2. In this study the overall data was congruent with the previous findings stating that ACS use decreases mortality and morbidity. These results indicate that the improved mortality of infants at 23–24 weeks’ gestation reflects the quality improvement of perinatal and neonatal intensive care, which is a prerequisite to the benefits of ACS.

Prognostic Value of Ionized Calcium Levels in Neonatal Sepsis

BACKGROUND

Despite recent advances in the treatment of neonatal infection, mortality rates and comorbidities associated with neonatal sepsis remain high. Hypocalcemia has been reported in critically ill patients, especially in as-sociation with sepsis. However, the importance of hypo-calcemia in neonatal sepsis has not been explored in detail.

OBJECTIVES

The purpose of this study was to evaluate the prognostic value of hypocalcemia in neonatal sepsis patients and to identify the risk factors associated with sepsis-related mortality.

METHODS

This retrospective study examined perinatal data from patients in a level IV neonatal in-tensive care unit between January 2010 and June 2016. Univariate analysis was performed to understand the differences in clinical and laboratory characteristics between patients with and without neonatal sepsis. Neonates with sepsis were further stratified as having ionized hypocalcemia (if serum ionized calcium [iCa] <1.0 mmol/L) or not. Uni- and multivariate logistic regression analyses were utilized to evaluate the predictive potential of iCa for identifying sepsis-related mortality.

RESULTS

A total of 472 neonates were enrolled in this study, including 169 neonates diagnosed with culture-proven sepsis and 303 neonates without infection (control group). The comparison of neonates with and without sepsis highlighted significant differences in levels of iCa (0.97 ± 0.26 vs. 1.12 ± 0.25 mmol/L), magnesium (0.75 ± 0.22 vs. 0.89 ± 0.12 mmol/L), and phosphate (2.26 ± 1.08 vs. 1.65 ± 0.85 mmol/L; all p < 0.001). When neonates with sepsis were stratified into 2 subgroups based on serum iCa, neonates with hypocalcemia showed higher rates of organ dysfunction than those with normal iCa, as well as higher rates of cardiovascular system dysfunction (37.35 vs. 17.44%), renal dysfunction (34.94 vs. 30.95%), disseminated intravascular coagulation (26.51 vs. 11.63%), and seizure (16.04 vs. 5.8%; all p < 0.05). Among all neonates who had sepsis, the mortality rate was 13.61%, and this rate was higher among neonates with hypocalcemia than among those with normal iCa (20.48 vs. 6.98%, p < 0.05). Uni- and multivariate analyses showed that acidosis, hypoalbuminemia, hypocalcemia, and hyperphosphatemia were independent prognostic markers of sepsis-related mortality. In receiver-operating characteristic curve analysis, the areas under the curve were 0.70 (95% CI 0.624-0.768; p = 0.0004), 0.74 (95% CI 0.671-0.808; p < 0.0001), 0.73 (95% CI 0.653-0.792; p = 0.0002), and 0.67 (95% CI 0.59-0.737; p = 0.0154) for serum albumin, iCa, phosphate, and acidosis, respectively. Based on these findings, we developed a nomogram to predict sepsis-related mortality.

CONCLUSIONS

Hypocalcemia is common in neonates with sepsis and is significantly associated with organ dysfunction and sepsis-related mortality.

The Influence of the Variation in Sepsis Rate between Neonatal Intensive Care Units on Neonatal Outcomes in Very-Low-Birth-Weight Infants

Sepsis is commonly known to affect neonatal outcomes. We assessed how much center-to-center variability of the sepsis rate affects the outcomes of very-low-birth-weight infants (VLBWIs). 7,493 VLBWIs registered in the Korean Neonatal Network from 2013 to 2016 were classified into three groups according to the sepsis rate: low sepsis group (LS) < 25^th percentile versus intermediate sepsis group (IS) 25^th–75^th versus high sepsis group (HS) ≥ 75^th. The incidence density of sepsis for the LS, IS, and HS groups were 1.17, 3.17, and 8.88 cases/1,000 person-days. After propensity score matching was done for multiple antenatal and perinatal factors, the odds ratio of death, moderate to severe bronchopulmonary dysplasia and/or death, periventricular leukomalacia, and survival without major morbidities for the HS group were 2.0 (95% confidence interval 1.4–2.8), 1.9 (1.5–2.4), 1.5 (1.1–2.3) and 0.7 (0.5–0.8) when compared with the IS group, and 2.2 (1.6–3.2), 2.3 (1.8–2.9), 2.0 (1.3–2.9), and 0.7 (0.6–0.9) when compared with the LS group. There were no significant differences in those outcomes between the LS and IS groups. Hence, nationwide quality improvements to control the sepsis rate especially in units with a high sepsis rate will be helpful to improve the outcomes of VLBWIs.

Conservative Non-intervention Approach for Hemodynamically Significant Patent Ductus Arteriosus in Extremely Preterm Infants

While persistent patent ductus arteriosus (PDA) in preterm infants has been known to be associated with increased mortality and morbidities including bronchopulmonary dysplasia, and necrotizing enterocolitis, there is minimal evidence supporting their causal relationships, and most traditional medical and/or surgical treatments have failed to show improvements in these outcomes. As such, the pendulum has swung toward the conservative non-intervention approach for the management of persistent PDA during the last decade; however, the benefits and risks of this approach are unclear. In this mini review, we focused on whom, when, and how to apply the conservative non-intervention approach for persistent PDA, especially in extremely preterm infants.

Initial and delayed thyroid-stimulating hormone elevation in extremely low-birth-weight infants

BACKGROUND

To determine the incidence, etiology, and outcomes of thyroid-stimulating hormone (TSH) elevation in extremely low-birth-weight infants (ELBWIs).

METHODS

Newborn thyroid screening data of 584 ELBWIs (birth weight, < 1000 g; gestational age, ≥ 23 weeks) were retrospectively analyzed to identify initial (≤ 2 postnatal weeks) and delayed (> 2 weeks) TSH elevations. Growth and neurodevelopmental outcomes at 2 years' corrected age (CA) were assessed according to levothyroxine replacement.

RESULTS

Initial and delayed TSH elevations were detected at CAs of 27 and 30 weeks, respectively, with incidence rates of 0.9 and 7.2%, respectively. All infants with initial TSH elevations had perinatal asphyxia, and 95% of those with delayed TSH elevation were exposed to various stressors, including respiratory support, drugs, and surgery within 2 weeks before diagnosis of TSH elevation. Free thyroxine (T4) levels were simultaneously reduced in 80 and 57% of infants with initial and delayed TSH elevations, respectively. Both initial and delayed TSH elevations were transient, regardless of levothyroxine replacement. Infants receiving levothyroxine replacement therapy had significantly higher TSH elevations, significantly lower free T4 levels, and significantly reduced mortality, compared to untreated infants. However, levothyroxine replacement had no significant effect on long-term growth and neurodevelopmental outcomes.

CONCLUSIONS

The timing of insult superimposition on hypothalamic-pituitary-thyroid axis maturation is a major determinant of initial or delayed TSH elevation in ELBWIs. Levothyroxine replacement did not affect growth or neurodevelopmental outcomes in this population.

Incidence and severity of transient hypothyroxinaemia of prematurity associated with survival without composite morbidities in extremely low birth weight infants

This study investigated the incidence of transient hypothyroxinaemia of prematurity (THOP) associated with survival without composite morbidities and the predictability of THOP severity in extremely low birth weight infants (ELBWIs). We retrospectively reviewed the medical records of 546 ELBWIs who underwent initial thyroid function tests within 14 postnatal days, with 156 ELBWIs from 2000 to 2005 (period I) and 390 from 2006 to 2013 (period II). The infants were stratified into 23–24, 25–26 and 27–28 weeks’ gestation subgroups within each period; the initial thyroxine (T4) level, mortality, clinical characteristics and composite morbidities, including bronchopulmonary dysplasia, intraventricular haemorrhage, necrotizing enterocolitis, and retinopathy of prematurity were analysed. The predictive value of the initial T4 level, Apgar score at 5 min, and clinical risk index for babies II (CRIB II) score for estimating mortality and survival with or without composite morbidities was assessed. Comparing period II and period I, the incidence of THOP was significantly decreased along with significantly increased survival without composite morbidities in ELBWIs at 25–28 weeks’ gestation. The severity of THOP showed significant associations with mortality and composite morbidities. The initial T4 level was most effective for predicting outcome compared with Apgar and CRIB II scores.

Practice variations and rates of late onset sepsis and necrotizing enterocolitis in very preterm born infants, a review

The burden of late onset sepsis (LOS) and necrotizing enterocolitis (NEC) remains high for newborns in low- and high-income countries. Very preterm born infants born below 32 weeks gestation are at highest risk because their immune system is not yet adapted to ex-utero life, providing intensive care frequently compromises their skin or mucosa and they require a long duration of hospital stay. An epidemiological overview is difficult to provide because there is no mutually accepted definition available for either LOS or NEC. LOS incidence proportions are generally reported based on identified blood culture pathogens. However, discordance in minimum day of onset and whether coagulase negative staphylococci or fungi should be included into the reported proportions lead to variation in reported incidences. Complicating the comparison are the absence of biomarkers, ancillary lab tests or prediction models with sufficiently high positive and/or negative predictive values. The only high negative predictive values result from negative blood culture results with negative lab results allowing to discontinue antibiotic treatment. Similar difficulties exist in reporting and diagnosing NEC. Although most publications base their proportions on a modified version of Bell's stage 2 or 3, comparisons are made difficult by the multifactorial nature of the disease reflecting several pathways to intestinal necrosis, the absence of a reliable biomarker and the unclear differentiation from spontaneous intestinal perforations. Comparable reports in very low birthweight infants range between 5% and 30% for LOS and 1.6% to 7.1% for NEC. Evidence based guidelines to support treatment are missing. Treatment for LOS remains largely empirical and focused mainly on antibiotics. In the absence of a clear diagnosis, even unspecific early warning signals need to be met with antibiotic treatment. Cessation after negative blood culture is difficult unless the child was asymptomatic from the beginning. As a result, antibiotics are the most commonly prescribed medications, but unnecessary exposure may result in increased risk for mortality, NEC, further infections and childhood obesity or asthma. Finding ways to limit antibiotic use are thus important and have shown a large potential for improvement of care and limitation of cost. Over recent decades, none of the attempts to establish novel therapies have succeeded. LOS and NEC proportions remained mostly stable. During the past 10 years however, publications emerged reporting a reduction, sometimes by almost 50%. Most concern units participating in a surveillance system using quality improvement strategies to prevent LOS or NEC (e.g., hand hygiene, evidence based "bundles", feeding onset, providing own mother's milk). We conclude that these approaches display a potential for wider spread reduction of LOS and NEC and for a subsequently more successful development of novel therapies as these often address the same pathways as the prevention strategies.

Mortality rate-dependent variations in the survival without major morbidities rate of extremely preterm infants

The effects of improved survival of EPT infants on morbidity among survivors remain largely controversial. This retrospective cohort study of the Korean Neonatal Network data investigated whether the mortality rate of 23-24 weeks' gestation was associated with survival without major morbidities in periviable 25-26 weeks' gestation infants. The 2,083 eligible infants with 23-26 weeks' gestation were grouped based on institutional mortality rate (group 1 and 2 ≤50% and >50% mortality rate, respectively, for 23-24 weeks' gestation) and were further divided into 23-24 and 25-26 weeks' gestation subgroups. The mortality rate of 23-24 weeks' gestation infants was significantly lower in group 1 (32.7%) than in group 2 (69.9%). The survival without major morbidities rate for 25-26 weeks' gestation infants was significantly higher in group 1 (31.2%) than in group 2 (18.5%). Antenatal steroid use and Apgar score at 5 min in group 1 were associated with decreased mortality and survival without major morbidities in 23-24 and 25-26 weeks' gestation infants, respectively. In the multivariate analyses, decreased mortality rates in 23-24 weeks' gestation infants were associated with higher survival without major morbidities rates in 25-26 weeks' gestation infants due to decreased bronchopulmonary dysplasia, periventricular leukomalacia, and late-onset sepsis. Evidence-based perinatal and neonatal practices, including antenatal steroid use and better delivery room care contributing to decreased mortality in periviable 23-24 weeks' gestation infants, were associated with lower morbidity and higher survival without major morbidities in more mature 25-26 weeks' gestation infants.

Deliveries at extreme prematurity: outcomes, approaches, institutional variation, and uncertainty

PURPOSE OF REVIEW

Medical decision making and practices surrounding extremely premature birth remains challenging for parents and care providers alike. Recently, concerns have been raised regarding wide practice variation, selection bias, and the limitations of outcomes data in this population. The purpose of this review is to summarize the recent literature relevant to deliveries at extreme prematurity with a focus on outcomes, approaches, and institutional variation.

RECENT FINDINGS

Newer data suggest that evidence-based clinical guidelines and protocols for both pregnant women and infants at extreme prematurity are emerging and may improve care and outcomes at lower gestational ages. It has also been recently shown that wide practice variation, selection bias, and methodological limitations of outcomes data reporting with respect to deliveries at extreme prematurity exist.

SUMMARY

Counseling at extreme prematurity should prioritize eliciting parental values and preferences with the goal of personalized shared decision-making. Providers should recognize limitations in counseling families at extreme prematurity, including selection bias, institutional variation, outcomes inaccuracies, prognostic uncertainty, and implicit biases. Standardized reporting of perinatal outcomes should be developed to help alleviate current outcomes misrepresentations and improve counseling at extreme prematurity. Education for providers in advanced communication skills is needed when counseling at extreme prematurity.