Variations in incidence of necrotizing enterocolitis in Canadian neonatal intensive care units

Clinical Correlates of Moderate-to-Severe Bronchopulmonary Dysplasia in Preterm Infants following Surgical Necrotizing Enterocolitis

OBJECTIVE

The aim of the study is to determine clinical correlates of moderate to severe bronchopulmonary dysplasia (BPD) in preterm infants following surgical necrotizing enterocolitis (NEC).

STUDY DESIGN

This is a retrospective, single-center cohort study comparing patients with moderate to severe BPD to patients with non/mild BPD among surgical NEC infants. BPD was defined by NIH 2001 consensus definition.

RESULTS

Of 92 consecutive neonates with surgical NEC, 77% (71/92) had moderate/severe BPD and 22% (21/92) had non/mild BPD. The patent ductus arteriosus (PDA) was significantly higher in those developing moderate/severe BPD (67.6% [48/71]) than non/mild BPD (28.6% [6/21]; p = 0.001). Postoperatively, infants with moderate/severe BPD had more severe acute kidney injury (AKI; 67.6 [48/71] vs. 28.6% [6/21]; p = 0.001), were intubated longer (40.5 [interquartile (IQR): 12, 59] vs. 6 days [IQR: 2, 13]; p <0.001), received more parenteral nutrition (109 [IQR: 77, 147] vs. 55 days [IQR: 19, 70]; p <0.001), developed higher surgical morbidity (46.5 [33/71] vs. 14.3% [3/21]; p = 0.008), had more intestinal failure (62.5 vs. 13.3%; p <0.001), required a longer hospital stay (161 [IQR: 112, 186] vs. 64 days [IQR: 20, 91]; p <0.001), and were more likely to need home oxygen. In a multivariable analysis, lower birth weight (OR = 0.3, [95% confidence interval (CI): 0.1-0.5]; p = 0.001), PDA (OR = 10.3, [95% CI: 1.6-65.4]; p = 0.014), and longer parenteral nutritional days (OR = 8.8; [95% CI: 2.0-43.0]; p = 0.005) were significantly and independently associated with higher odds of moderate/severe versus non-/mild BPD.

CONCLUSION

Development of moderate/severe BPD occurred in the majority of preterm infants with surgical NEC in this consecutive series. Preterm infants with moderate/severe BPD were more likely to have a PDA before NEC. Development of moderate/severe BPD was associated with significantly greater burden and duration of postoperative morbidity following surgical NEC. Identifying surgical NEC infants at increased risk of moderate/severe BPD and developing lung protection strategies may improve surgical NEC outcomes.

KEY POINTS

· Three-fourths of preterm infants experienced severe lung injury following surgical NEC.. · The infants with severe moderate/severe BPD were most likely associated with greater duration of postoperative morbidity.. · There is need to understand and develop lung protective strategies in infants with surgical NEC..

Outcomes by disease onset, sex, and intervention in neonates with SIP and surgical NEC

BACKGROUND

Outcomes of infants following surgical necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) categorized by the age of onset, interventions, and sex are not well defined.

METHODS

Retrospective comparison of infants categorized by age of onset (NEC at <10, 10-20, and >20 days) and SIP at <7 versus ≥7 days), sex, and intervention [Penrose Drain (PD) vs. laparotomy].

RESULTS

A total of 114 infants had NEC and 37 had SIP. On multinomial logistic regression, infants with NEC/SIP onset >20 days had significantly lower odds of small bowel involvement (aOR = 0.07, 95% CI: 0.01-0.33, p = 0.001), higher necrosis (aOR = 3.59, 95% CI: 1.34-9.65, p = 0.012) and higher CRP (p = 0.004) than onset <10 days. Initial laparotomy was associated with more bowel loss (24.1 cm [12.3; 40.6] vs.12.1 [8.00; 23.2]; p = 0.001), small and large intestine involvement (47.1% vs 17.2%; p = 0.01), and ileocecal valve resection (42% vs. 19.4%; p = 0.036) than initial PD therapy. Females underwent fewer small bowel resections (52.3% vs 73.6%; p = 0.025) but had higher surgical morbidity (53.7% vs. 24.7%.; p = 0.001) than males.

CONCLUSION

Clinical, radiological, and histopathological presentation and outcomes in preterm infants with surgical NEC/SIP are associated with age of disease onset, sex, and initial intervention.

IMPACT

Neonates with surgical NEC onset >20 days had more severe necrosis, inflammation, kidney injury, and bowel loss than those with <10 days. Initial laparotomy was associated with later age onset, more bowel loss, and ileocecal valve resection compared to initial PD treatment, but not with differences in mortality or length of stay. Female sex was associated with lower maturity, more placental malperfusion, less often small bowel involvement, lower pre-NEC hematocrit as well as higher surgical morbidity than males. Whether the management of surgical NEC and SIP should differ by the age of onset requires further investigation.

Risk factors for postoperative complications in preterm infants with surgical necrotizing enterocolitis and associated outcomes

BACKGROUND

We aim to determine clinical risk factors for postoperative complications in preterm infants with surgical necrotizing enterocolitis (NEC) or spontaneous intestinal perforation (SIP).

METHODS

A retrospective cohort study of preterm infants with surgical NEC or SIP to compare clinical factors between those with and without postoperative complications.

RESULTS

78/109 (71.5%) infants had any complication following surgical NEC. Adhesions (20/35, 57.1%) and wound infection (6/35, 17.1%) were the most common single surgical complications. Patients with a single surgical complication (35/66, 53%) were significantly less likely to be exposed to antenatal steroids, more frequently had a jejunostomy, needed a central line longer, and had a longer length of stay than those without any surgical complication. Infants with > 1 surgical complication (43/71, 60.5%) included mainly females, and had AKI more frequently at NEC onset, lower weight z-scores and lower weight for length z- scores at 36 weeks PMA than those without any complications.On multinomial logistic regression, antenatal steroids exposure (OR 0.23 [CI 0.06, 0.84]; p = 0.027) was independently associated with lower risk and jejunostomy 4.81 (1.29, 17.9) was independently associated with higher risk of developing a single complication. AKI following disease onset (OR 5.33 (1.38, 20.6), P = 0.015) was independently associated with > 1 complication in surgical NEC/SIP infants.

CONCLUSION

Infants with postoperative complications following surgical NEC were more likely to be female, have additional morbidities, and demonstrate growth failure at 36 weeks PMA than those without surgical complications. There was no difference in mortality between those with and without surgical complications.

Gestational age-specific clinical correlates of acute kidney injury in preterm infants with necrotizing enterocolitis

BACKGROUND

To study the gestational age-specific risk factors and outcomes of severe acute kidney injury (AKI) in neonates with necrotizing enterocolitis (NEC).

METHODS

Retrospective cohort study comparing gestational age (GA)-specific clinical data between infants without severe AKI (stage 0/1 AKI) and those with severe AKI (stages 2 and 3 AKI) stratified by GA ≤27 and >27 weeks.

RESULTS

Infants with GA ≤27 weeks had double the rate of severe AKI (46.3% vs. 20%). In infants with GA >27 weeks, male sex, outborn, and nephrotoxic medication exposure were associated with severe AKI. On multivariable logistic regression, in infants with GA ≤27 weeks, surgical NEC (OR 35.08 (CI 5.05, 243.73), p < 0.001) and ostomy (OR 6.2(CI 1.29, 29.73), p = 0.027) were associated with significantly higher odds of severe AKI. Surgical NEC infants with GA >27 weeks and severe AKI were significantly more likely to be outborn, have later NEC onset, need dopamine, and have longer hospitalization (158 days [110; 220] vs.75.5 days [38.8; 105]; p = 0.007 than those with non-severe AKI.

CONCLUSION

In neonates with NEC, surgical intervention was associated with moderate-to-severe AKI in infants with GA ≤27 weeks and with longer hospitalization in infants with GA >27 weeks.

IMPACT

In both cohorts need for surgery, stoma, cholestasis, and mechanical ventilation were associated with severe AKI; however, the infants with GA <27 weeks had twice the risk of severe AKI than GA >27 weeks group. The longer exposure to nephrotoxic medication and referral need were significant risk factors for AKI in GA >27 weeks group. GA-specific kidney protective and monitoring strategies to prevent AKI and its consequences are needed to improve the clinical outcomes in neonates with NEC. Understanding the risk factors and short- and long-term outcomes unique to different GA groups will help inform those strategies.

Clinical Correlates of Cholestasis in Preterm Infants with Surgical Necrotizing Enterocolitis

Background

We sought to investigate the clinical determinants and outcomes of cholestasis in preterm infants with surgical necrotizing enterocolitis (sNEC).

Methods

Retrospective comparison of clinical information in preterm infants who developed cholestasis vs those who did not.

Results

Sixty-two (62/91, 68.1%) infants with NEC developed cholestasis at any time following the onset of illness. Cholestasis was seen more frequently in those who had received ionotropic support at 24 hours following sNEC diagnosis (87.1% vs 58.6%; p = 0.002), had higher mean C-reactive protein levels 2 weeks after NEC diagnosis (p = 0.009), had blood culture-positive sepsis [25 (40.3%) vs 4 (13.8%); p = 0.011], received parenteral nutrition (PN) for longer durations (108.4 ± 56.63 days vs 97.56 ± 56.05 days; p = 0.007), had higher weight-for-length z scores at 36 weeks' postmenstrual age [-1.0 (-1.73, -0.12) vs -1.32 (-1.76, -0.76); p = 0.025], had a longer length of hospital stay (153.7 ± 77.57 days vs 112.51 ± 85.22 days; p = 0.024), had intestinal failure more often (61% vs 25.0%, p = 0.003), had more surgical complications (50% vs 27.6%; p = 0.044), and had >1 complication (21% vs 3.4%; p = 0.031). Using linear regression, the number of days after surgery when feeds could be started [OR 15.4; confidence interval (CI) 3.71, 27.13; p = 0.009] and the postoperative ileus duration (OR 11.9, CI 1.1, 22.8; p = 0.03) were independently associated with direct bilirubin between 2 and 5 mg/dL (mild-moderate cholestasis) at 2 months of age. The duration of PN was independently associated with direct bilirubin >5 mg/dL (severe cholestasis) at 2 months of age in these patients.

Conclusion

Cholestasis was seen in 68% of infants following surgical NEC. The most likely contributive factors are intestinal failure and subsequent PN dependence for longer periods. Our data suggest that identification and prevention of risk factors such as sepsis and surgical complications and early feeds following NEC surgery may improve outcomes.

Clinical impact of timing of surgery on outcomes in preterm infants with surgical necrotizing enterocolitis

Background

The clinical impact of the timing of surgery on outcomes in preterm infants with surgical necrotizing enterocolitis (NEC) is not well defined.

Aim

We sought to investigate the impact of the different timing of surgery from the day of NEC diagnosis on clinical outcomes in preterm infants with surgical NEC.

Study Design

Retrospective Cohort Study.

Subjects

Preterm 75 infants admitted between January 2013 and December 31, 2018, with an NEC (Bell stage III) diagnosis.

Outcomes

Comparison of clinical information by the timing of surgery at three different time points (less and more than 48 hours, 96 hours, and 168 hours) in preterm infants with surgical NEC.

Results

75 infants were included in the analysis. Those who received surgery after 48 hours (n= 29/75) had lower median gestational age, lower birth weight, had less pneumoperitoneum, were out born less frequently, had higher acute kidney injury, were intubated and ventilated more frequently, and had higher hemorrhagic and reparative lesions on histopathology than those receiving surgery after 48 hours. Infants receiving surgery after 96 hours had similar trends expect had significantly lower hematocrit and more prolonged parenteral nutrition dependence than less than 96 hours group. The infants receiving surgery after one week had significantly lower birth weight and had higher reparative changes and cholestasis than those receiving surgery < 1 week.There was no significant impact of surgery timing on the length of bowel loss, surgical morbidity, Bronchopulmonary dysplasia, white matter injury, and mortality.

Conclusion

The infants receiving surgery later were young and smaller and received parenteral nutrition longer with no significant impact on morbidities and mortality. Our data point out that there are advantages of operating early with fewer morbidities which need further confirmation and evaluation in large multicentric prospective studies or clinical trials.

Clinical and Growth Correlates of Retinopathy of Prematurity in Preterm infants with Surgical Necrotizing Enterocolitis and intestinal Perforation

Background

we sought to determine the clinical and growth parameters associated with retinopathy of prematurity (ROP) in infants with necrotizing enterocolitis (NEC) and spontaneous ileal perforation (SIP).

Methods

Retrospective cohort study comparing clinical information before and following NEC/SIP onset in neonates with and without severe ROP (Type 1 and 2).

Results

Those with severe ROP (32/109, 39.5%) had lower GA, BW, chorioamnionitis, later median onset of ROP diagnosis and received Penrose drain and had higher AKI, poor weight z scores, poor linear growth, longer duration of ventilation and higher FIo2 than those without ROP following NEC/SIP. The GA and diagnosis at later age remained significant for any ROP on multi regression modelling.

Conclusion

The surgical NEC/SIP infants with severe ROP were more likely to be younger, smaller, had AKI, had higher oxygen exposure and poor weight gain and linear growth than those without severe ROP.

Association of Placental Pathologic Findings with the Severity of Necrotizing Enterocolitis in Preterm infants - A Matched Case-Control Study

OBJECTIVE

To determine the association of placental pathology with the severity of necrotizing enterocolitis (NEC) in preterm infants.

METHODS

This single-center matched case-control study included infants with NEC (n = 107) and gestational age and birth weight-matched controls (n = 130), born between 2013 and 2020. Placentas were evaluated according to the Amsterdam Placental Workshop Group Consensus Statement.

RESULTS

Acute histologic chorioamnionitis with the fetal response was significantly more common in infants with surgical NEC vs. medical NEC (35.4% vs. 15.3%; p = 0.02). On regression model, infants with multiple placental pathologies (OR 2.16; 95% CI 1.01 - 4.73; p = 0.04) and maternal vascular malperfusion (OR 2.2; 95% CI 1.12 - 4.51; p = 0.02) had higher odds of either medical or surgical NEC than controls.

CONCLUSION

Infants with multiple placental lesions, including placental inflammatory and vascular lesions, were at higher risk of medical or surgical NEC in the postnatal period.

Correlation of placental pathology with the postoperative outcomes and white matter injury in preterm infants following necrotizing enterocolitis

BACKGROUND

To determine the association of placental pathologic lesions with postoperative outcomes, survival, and white matter injury (WMI) in preterm infants with NEC.

METHODS

A retrospective chart review of 107 neonates with NEC (Bell stage > IIa) from Jan 2013- June 2020 was completed. Demographic, clinical, and outcome data were compared between infants with or without placental pathologic lesions.

RESULTS

In this cohort, 59/107 (55%) infants had medical NEC, and 48 (45%) had surgical NEC. The infants had a mean gestational age of 28.1±3.7 weeks and a birth weight of 1103±647 g. Maternal vascular malperfusion (82/107, 76.6%) and acute histological chorioamnionitis (42, 39.3%) were the most common pathological placental lesions. Acute histologic chorioamnionitis with fetal inflammatory response was more common in infants with surgical NEC vs. medical NEC (35.4% vs. 15.3%; p = 0.02). The NEC Infants with WMI on brain MRI scans had a significantly higher incidence of acute histological chorioamnionitis (52% vs. 27.8%; P = 0.04). No significant differences in mortality, length of stay and postoperative outcomes in neonates with and without acute histologic chorioamnionitis with fetal inflammatory response were noted. On unadjusted logistic regression, acute histologic chorioamnionitis without fetal inflammatory response was also associated with higher odds of WMI (OR 2.81; 95% CI 1.05-7.54; p = 0.039).

CONCLUSION

Acute histological chorioamnionitis without fetal inflammatory response was associated with higher odds of WMI in infants with NEC, with no significant impact on mortality and other postoperative outcomes.

Clinical impact of analgesic-sedative agents and peri-operative clinical status on white matter brain injury in preterm infants following surgical NEC

BACKGROUND

The potential influence of exposure to analgesic-sedative agents (ASA) before, during, and after surgical NEC and peri-operative clinical status on white matter injury (WMI) in preterm infants has not been fully defined, and a comprehensive evaluation may inform future research and clinical interventions.

METHODS

A retrospective study comparing ASA exposure before/during /after surgical NEC and peri-operative clinical status in neonates with and without WMI.

RESULTS

Infants with any WMI (grade 2-4, n = 36/67, 53.7%) had a higher number of surgical procedures receiving ASA (5 [IQR: 3, 8] vs. 3 [2, 4]; p = 0.002) and had a longer duration of hypotension during their first (48.0 hours [26.0, 48.0] vs. 15.5 [6, 48]; p = 0.009) and second surgery (20 hours [0, 48h] vs. 0 [0, 22]; p = 0.017), received more hydrocortisone (35% vs.13.3%,p = 0.04) than those without any WMI. There were no differences in fentanyl/morphine/midazolam exposure before/during/after the NEC onset in the two groups.Infants with severe WMI (19/67, 28.3%, grade 3/4) had a higher incidence of AKI (P = 0.004), surgical morbidity (p = 0.047), more surgical procedures (6.5 [3, 10] vs. 4 [2, 5]; p = 0.012), and received higher mean fentanyl doses(p = 0.03) from birth until NEC onset than those without severe WMI. The univariate associations between these factors and severe WMI remained insignificant after multivariable logistic regression.

CONCLUSION

Infants with WMI had more surgical procedures receiving ASA and had a longer duration of hypotension during surgeries. A large multicenter prospective study is needed to understand the full impact of ASA.

Clinical outcomes and gestational age based prediction of pneumatosis intestinalis in preterm infants with necrotizing enterocolitis

BACKGROUND

To determine the clinical implications and gestation age-specific diagnostic predictability of pneumatosis in preterm infants with necrotizing enterocolitis (NEC).

METHODS

A retrospective study on abdominal radiographs comparing clinical and radiological information in infants with and without pneumatosis.

RESULT

Our findings disproved our hypothesis. Pneumatosis was seen more frequently in infants with higher gestational age [28.4 (26.1-32.4) vs. 26.4 (24.3-29) weeks; p < 0.001] and birth weight [1110 (762-1768) vs. 770 (645-1022) grams; p < 0.001] and were more likely delivered vaginally (39.1% vs. 21.7%, p = 0.01). Portal venous gas was seen frequently on radiographs (10.3% vs. 0%, p < 0.001), but not pneumoperitoneum (20.7% vs. 36.7%, p = 0.02). Infants with pneumatosis frequently developed acute kidney injury, with higher serum creatinine (16.5% vs. 4.5%, p = 0.02) and frequent oliguria (12.9% vs. 2.7 %; p = 0.043) and had higher C-reactive protein levels at 24 and 96 hours (p < 0.002). Receiver operating curves for pneumatosis showed GA >28 weeks and birth weight > 1000 gm to have a sensitivity of 58.6% and specificity of 72.5%.

CONCLUSION

Contrary to our hypothesis, infants who developed pneumatosis during NEC were more mature with a higher gestational age and birth weight than those who did not.

Machine learning-based risk factor analysis of necrotizing enterocolitis in very low birth weight infants

This study used machine learning and a national prospective cohort registry database to analyze the major risk factors of necrotizing enterocolitis (NEC) in very low birth weight (VLBW) infants, including environmental factors. The data consisted of 10,353 VLBW infants from the Korean Neonatal Network database from January 2013 to December 2017. The dependent variable was NEC. Seventy-four predictors, including ambient temperature and particulate matter, were included. An artificial neural network, decision tree, logistic regression, naïve Bayes, random forest, and support vector machine were used to evaluate the major predictors of NEC. Among the six prediction models, logistic regression and random forest had the best performance (accuracy: 0.93 and 0.93, area under the receiver-operating-characteristic curve: 0.73 and 0.72, respectively). According to random forest variable importance, major predictors of NEC were birth weight, birth weight Z-score, maternal age, gestational age, average birth year temperature, birth year, minimum birth year temperature, maximum birth year temperature, sepsis, and male sex. To the best of our knowledge, the performance of random forest in this study was among the highest in this line of research. NEC is strongly associated with ambient birth year temperature, as well as maternal and neonatal predictors.

Gestational age-specific hematological patterns in preterm infants following necrotizing enterocolitis

OBJECTIVE

To investigate gestational age (GA) specific hematological and transfusion response patterns in preterm infants following necrotizing enterocolitis (NEC).

DESIGN

A retrospective study comparing hematological/transfusion information in three GA groups' infants: Group A ≤ 28 weeks. Group B 28-32 weeks, Group C > 32 weeks following necrotizing enterocolitis.

RESULTS

Group A infants responded with significantly higher WBC count, thrombocytopenia, higher absolute neutrophil, and higher absolute monocyte and lower absolute lymphocyte counts following NEC onset, received more blood transfusions before NEC onset (59.8 versus 30.0%; p = .007), and had higher odds of surgical NEC (OR 3.39 [95% CI 1.19-10.38]; p = .02) than group C. One unit increase in absolute lymphocyte count on the day, and 24 h following NEC was significantly associated with lower surgical NEC odds than groups C.

CONCLUSION

The infant's in-group A had significantly different hematological response patterns following NEC than infants with higher gestational age (groups B and C).

Clinical impact of NEC-associated sepsis on outcomes in preterm infants

OBJECTIVE

To determine risk factors and outcomes of necrotizing enterocolitis (NEC)-associated sepsis in infants with NEC.

METHODS

A retrospective review comparing demographic and clinical information in infants with and without NEC-associated sepsis (defined as positive blood culture at the time of NEC onset).

RESULTS

A total of 209 infants with medical (n = 98) and surgical NEC (n = 111) had a median gestational age of 27 weeks (IQR 25; 30.5) and a median birth weight of 910 g [IQR 655; 1138]. Fifty of 209 (23.9%) infants had NEC-associated sepsis. Infants with NEC-associated sepsis had lower median GA (26.4 vs. 27.4 weeks; p = 0.01), lower birth weight (745 vs. 930 g; p = 0.009), were more likely mechanically ventilated [p < 0.001], received dopamine [p < 0.001], had more evidence of acute kidney injury [60% vs. 38.4%, p = 0.01], longer postoperative ileus (16 [13.0; 22.0] vs. 12 [8; 16] days; p = 0.006), higher levels of C-reactive protein, lower platelet counts, longer hospitalization compared to infants without NEC-associated sepsis. On multivariate regression, cholestasis was an independent risk factor for NEC-associated sepsis (OR 2.94; 95% CI 1.1-8.8, p = 0.038).

CONCLUSION

NEC-associated sepsis was associated with greater hemodynamic support, acute kidney injury, longer postoperative ileus, and hospitalization on bivariate analysis, and cholestasis was associated with higher odds of sepsis on multi regression analysis.

IMPACT

NEC-associated sepsis was present in 24% of infants with NEC. Gram-positive bacteria, Gram-negative bacteria, and Candida were found in 15.3%, 10.5%, and 2.8% of cases, respectively. Infants with NEC-associated sepsis had a greater inflammatory response (CRP levels), received more blood transfusion before NEC onset, frequently needed assisted ventilation ionotropic support, and had acute kidney injury after NEC onset. NEC infants with Gram-negative sepsis had higher portal venous gas, received more platelet transfusions before NEC onset, and had higher CRP levels and lower median lymphocyte counts at 24 h after NEC onset than those with Gram-positive sepsis.

Clinical impact of severe acute kidney injury on post-operative and brain injury outcomes in preterm infants following surgical necrotizing enterocolitis

BACKGROUND

To evaluate post-operative outcomes and white matter injury (WMI) using brain MRI at term equivalent in neonates with and without severe acute kidney injury (AKI) following surgical necrotizing enterocolitis (NEC).

METHODS

A retrospective cohort study comparing neonates with severe (Stage 2/3) vs. other (no AKI/Stage 1) AKI using KDIGO classification with multivariable models assessing this association in the context of multiple systemic comorbidities.

RESULTS

Of 103 neonates with surgical NEC, 60 (58%) had severe AKI. Those with severe AKI had lower birth weight (BW; 715 vs. 950 g; p = .023), more frequently treated with indomethacin (18.3 vs. 2.4%); p = .014), higher CRP levels at 24 h after NEC onset (14.4 [6.4-19.8] vs. 4.8 [1.6-13.4]; p = .005), higher presence of cholestasis (73.3 vs. 51.2%); p = .023), later age of NEC onset (14 vs. 7 d); p = .004), longer length of bowel resected (14.9 vs. 4.3 cm); p = .011), longer post-operative ileus days (14 vs. 9 d); p < .001), longer post-operative days at starting enteral feedings (15 vs. 10 d; p < .001), longer days of attainment of full enteral feedings (75 vs. 44.5 d; p = .008) and longer length of stay (140.5 vs. 94 d; p = .028) compared to those without severe AKI. Compared to infants without AKI by serum creatinine, those with AKI had significantly more cases of white matter abnormality (WMA; 90 vs. 36.6%; p < .001) and retinopathy of prematurity (63.9 vs. 35.3%; p = .017). In addition, the presence of AKI Stage 2 and 3 by serum creatinine was independently associated with higher odds of sustaining severe WMI level on an ordinal scale (OR = 6.2; 95% CI = (1.1-35.5); p = .041).

CONCLUSIONS

Neonates with severe AKI following surgical NEC were more likely to experience longer post-operative morbidity and higher WMI by MRI at term.

Bench to bedside - new insights into the pathogenesis of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the leading cause of death and disability from gastrointestinal disease in premature infants. Recent discoveries have shed light on a unifying theorem to explain the pathogenesis of NEC, suggesting that specific treatments might finally be forthcoming. A variety of experiments have highlighted how the interaction between bacterial signalling receptors on the premature intestine and an abnormal gut microbiota incites a pro-inflammatory response in the intestinal mucosa and its underlying endothelium that leads to NEC. Central amongst the bacterial signalling receptors implicated in NEC development is the lipopolysaccharide receptor Toll-like receptor 4 (TLR4), which is expressed at higher levels in the premature gut than in the full-term gut. The high prenatal intestinal expression of TLR4 reflects the role of TLR4 in the regulation of normal gut development, and supports additional studies indicating that NEC develops in response to signalling events that occur in utero. This Review provides new evidence explaining the pathogenesis of NEC, explores new findings indicating that NEC development has origins before birth, and discusses future questions and opportunities for discovery in this field.

Brain injury in preterm infants with surgical necrotizing enterocolitis: clinical and bowel pathological correlates

BACKGROUND

The objective of this study was to determine the risk factors and outcomes of white matter brain injury (WMBI) on magnetic resonance imaging (MRI) at term-equivalent age in infants with surgical necrotizing enterocolitis (NEC).

METHODS

This retrospective study compared clinical/pathological information between infants with and those without WMBI.

RESULTS

Out of 69 infants with surgical NEC, 17 (24.6%) had mild WMBI, 13 (18.8%) had moderate WMBI, and six (8.7%) had severe WMBI on the brain MRI. Several clinical factors (gestational age, more red blood cell (RBC) transfusions before NEC onset, pneumoperitoneum, earlier NEC onset age, postoperative ileus, acute kidney injury (AKI) by serum creatinine, postnatal steroids, hospital stay) and histopathological findings (necrosis, hemorrhage) had univariate associations with WMBI. Associations with RBC transfusion (odds ratio (OR) 23.6 [95% confidence interval (CI): 4.73-117.97]; p = 0.0001), age at NEC onset (OR 0.30 [95%CI: 0.11-0.84]; p = 0.021), necrosis (OR 0.10 [95%CI: 0.01-0.90]; p = 0.040), and bowel hemorrhage (OR 7.79 [95%CI: 2.19-27.72]; p = 0.002) persisted in multivariable association with grade 3-4 WMBI. The infants with WMBI had lower mean motor, cognitive, language scores, and higher ophthalmic morbidity at 2 years of age.

CONCLUSIONS

The WMBI was most likely associated with earlier NEC onset, higher RBC transfusions, and less necrosis and greater hemorrhage lesions on intestinal pathology in preterm infants with surgical NEC.

IMPACT

In preterm infants with surgical NEC, brain MRI showed injury in the white matter in 52%, gray matter in 10%, and cerebellar region in 30%. Preterm infants with severe WMBI (grade 3-4) had less necrosis and greater hemorrhagic lesions on histopathology of the bowel. Preterm infants with WMBI were more likely to have a more severe postoperative course, AKI, and longer length of hospitalization. Neuroprotective strategies to prevent brain injury in preterm infants with surgical NEC are needed with the goal of improving the neurodevelopmental outcomes.

The role of ultrasound in necrotizing enterocolitis

Ultrasound has proved to be a useful modality for enhancing the diagnostic accuracy of necrotizing enterocolitis and associated complications. The standard imaging algorithm for evaluating necrotizing enterocolitis includes radiographs and clinical symptoms, the combination of which constitutes the Bell criteria. Major limitations of using the Bell criteria for diagnosing and clinically managing necrotizing enterocolitis include low diagnostic accuracy of radiographs and nonspecific symptomatology of preterm infants. In this regard, US can offer additional insights into bowel health by helping to characterize bowel motility, echogenicity, thickness, pneumatosis and perfusion. Extramural findings such as portal venous gas, nature and extent of ascites, and pneumoperitoneum can also be assessed. Recently, contrast-enhanced US was explored in a case series of preterm bowel disease and its diagnostic utility warrants further investigation. This article reviews the US features of necrotizing enterocolitis and highlights the role of US as a complement to radiographs, as well as the emerging use of contrast-enhanced US in necrotizing enterocolitis.

Low technology, mild controlled hypothermia for necrotizing enterocolitis treatment: an initiative to improve healthcare to preterm neonates

Necrotizing enterocolitis (NEC) treatment remains unchanged for years. Data suggest that mild controlled hypothermia could potentially improve NEC outcomes. Our units presented unfavourable outcomes on NEC. The aim was to assess our experience with low technology, mild controlled hypothermia on NEC outcomes, and improve preterm infants' healthcare. This was a single-center quality improvement study with retrospective cohort design at the neonatal intensive care unit in the university hospital. Forty-three preterm infants with NEC (Modified Bell's Stage II/III) were included: 19 in the control group (2015-2018) and 24 in the hypothermia group (2018-2020). The control group received standard treatment (fasting, abdominal decompression, and broad-spectrum antibiotics). The hypothermia group underwent cooling to 35.5 °C for 48 h after NEC diagnosis, along with conventional treatment. The primary outcomes are intestinal perforation, need for surgery, duration of parenteral nutrition, death, and extensive resection of the small intestine. There was no statistical difference in the NEC score. The hypothermia group required less surgery (aRR 0.40; 95% CI 0.19-0.85), presented less bowel perforation (aRR 0.39; 95% CI 0.18; 0.83), had a shorter duration of parenteral nutrition (aHR 5.28; 95% CI 1.88-14.89), did not need extensive intestinal resection, (0 vs 15.7%), and did not experience any deaths (0 vs 31.6%).Conclusions: In our experience, low technology, mild controlled hypothermia was feasible, not related to adverse effects, and effective treatment for NEC Modified Bell's Stage II/III. It avoided surgery, bowel perforation, and extensive intestinal resection; reduced mortality; and shortened parenteral nutrition duration. What is Known: • New approaches have been proposed to avoid enterocolitis incidence; however, the treatment of enterocolitis stage 2 has been the same for decades, and unfavourable outcomes remain despite conventional management. • Studies suggest that hypothermia can be an alternative to enterocolitis treatment. What is New: • Mild controlled hypothermia can be an additional practice to treat enterocolitis stage 2, is feasible, and is not related to adverse effects to preterm infants. • It can decrease surgery needs, duration of parenteral nutrition, and death and avoids extensive intestinal resection in preterm infants.

Severe acute kidney injury in neonates with necrotizing enterocolitis: risk factors and outcomes

BACKGROUND

To study the risk factors and outcomes of severe acute kidney injury (AKI) in neonates with necrotizing enterocolitis.

METHODS

Retrospective chart review of 202 neonates with necrotizing enterocolitis (NEC) (Bell stage >IIa) from 2013 to 2018. AKI was defined as per-modified neonatal Kidney Disease: Improving Global Outcomes criteria. Demographic, clinical, and outcome data were compared between neonates without severe AKI (stage 0 and 1 AKI) and those with severe AKI (stage 2 and 3 AKI).

RESULTS

Severe AKI occurred in 66/202 (32.6%) of neonates after NEC diagnosis and after 61/104 (58.7%) of surgical NEC diagnoses. On adjusted model, surgical NEC [adjusted odds ratio (aOR) = 30.6; 95% confidence interval (CI) = 8.9, 130.6], outborn [aOR = 3.9; 95% CI = 1.54, 11.0], exposure to antenatal steroids [aOR = 3.0; 95% CI = 1.1, 8.9], and positive blood culture sepsis [aOR = 3.5; 95% CI = 1.3, 10.0] had increased odds for severe AKI. Those with severe AKI required longer hospitalization [124 days (interquartile range (IQR) 88-187) vs. 82 days (IQR 42-126), p < 0.001].

CONCLUSIONS

Severe AKI is common in neonates with NEC who require surgical intervention, are outborn, have positive blood culture sepsis, and receive antenatal steroids. Severe AKI is associated with a significantly longer length of hospitalization.

IMPACT

Neonates with NEC, who are transferred from outside hospitals, require surgical NEC management, and/or have a positive blood culture at NEC onset are at the highest odds for severe (stages 2 and 3) AKI. Assessment of urine output is important for patients with NEC. Without it, 11% of those with severe AKI would have been misdiagnosed using serum creatinine alone. Kidney-protective strategies in the pre-, peri-, and postoperative period may improve the morbidity and mortality associated with severe AKI in neonates with NEC.

Hematological predictors of mortality in neonates with fulminant necrotizing enterocolitis

OBJECTIVE

Determine whether hematological and transfusion patterns following, the onset of NEC can identify infants likely to develop fulminant, fatal necrotizing enterocolitis (NEC).

DESIGN

Determine hematological predictors of fulminant NEC.

RESULTS

Of 336 neonates with NEC, 35 (10%) who developed fulminant NEC were born with higher birth weights and more frequently developed radiologically evident pneumoperitoneumand/or portal venous gas. Following the diagnosis of NEC, these infants were more likely to rapidly develop thrombocytopenia, lymphopenia, neutropenia, and lower total white blood cell counts compared to medical/surgical non-fulminant type. They were also more likely to have received a red blood cell (RBC) transfusion (76.7% vs. 53.1%, p = 0.001) within 48 h after disease onset and platelet transfusion (24.2% vs. 11.7%; p = 0.03) before the onset of NEC.

CONCLUSION

Neonates with fulminant NEC frequently developed thrombocytopenia, lymphopenia, neutropenia, and leukopenia, received RBC transfusions after or platelet transfusions before the onset of NEC developed the fulminant disease.

Intervention and Outcome for Neonatal Hypotension

Many observational studies have shown that infants with blood pressures (BPs) that are in the lower range for their gestational age tend to have increased complications such as an increased rate of significant intraventricular hemorrhage and adverse long-term outcome. This relationship does not prove causation nor should it create an indication for treatment. However, many continue to intervene with medication for low BP on the assumption that an increase in BP will result in improved outcome. Only adequately powered prospective randomized controlled trials can answer the question of whether individual treatments of low BP are beneficial.

Hope on the horizon: promising novel therapies for necrotizing enterocolitis

Necrotizing enterocolitis (NEC) remains among the most common and devastating diseases in neonates. Despite advances in neonatal clinical care, specific treatment strategies and diagnostic modalities remain lacking. As a result, morbidity and mortality remain high. Improved understanding of the pathogenesis of NEC has the potential for improved therapeutics. Some of the areas of research leading to promising discoveries include inhibition of Toll-like receptor signaling, modulation of vascular endothelial growth factor signal pathways, defining metabolomic alterations in NEC to discover potential biomarkers, probing for genetic predispositions to NEC susceptibility, determining mechanistic relations between anemia and NEC, and microflora modulation through the use of probiotics. All of these areas may represent novel promising approaches to the prevention and treatment of NEC. This review will focus on these current and possible therapeutic perspectives.

Recent Advances in Prevention and Therapies for Clinical or Experimental Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is one of the most severe diseases of preterm neonates and has a high mortality rate. With the development of inspection techniques and new biomarkers, the diagnostic accuracy of NEC is constantly improving. The most recognized potential risk factors include prematurity, formula-feeding, infection, and microbial dysbiosis. With further understanding of the pathogenesis, more effective prevention and therapies will be applied to clinical or experimental NEC. At present, such new potential prevention and therapies for NEC are mainly focused on the Toll-like receptor 4 inflammatory signaling pathway, the repair of intestinal barrier function, probiotics, antioxidative stress, breast-feeding, and immunomodulatory agents. Many new studies have changed our understanding of the pathogenesis of NEC and improve our approaches for preventing and treating of NEC each year. This review provides an overview of the recent researches focused on clinical or experimental NEC and highlights the advances made within the past 5 years toward the development of new potential preventive approaches and therapies for this disease.

Necrotizing Enterocolitis Associated with Congenital Heart Disease: a Different Entity?

BACKGROUND

Necrotizing enterocolitis (NEC) predominantly occurs in preterm infants (PT-NEC). In term neonates, NEC occurs more frequently when a congenital heart disease is present (CHDNEC). Our aim was to evaluate differences and similarities in disease characteristics of PT-NEC versus CHD-NEC.

METHODS

In this retrospective case-control study we identified all CHD infants who developed NEC Bell's stage ≥2 in our center from 2004 to 2014. We randomly selected (1:2 ratio) PT-NEC infants from the same period. Biochemical and clinical variables were retrieved from patient files.

RESULTS

We found 18 CHD-NEC infants and selected 36 PT-NEC infants (gestational age 28.3 [25-35.6] weeks vs. 38.6 [31.7-40.7] weeks). Postnatal age at onset was significantly lower in CHD-NEC patients (4 [2-24] vs. 11 [4-41] days, p < 0.001). Lowest pH levels were lower (7.21 [7.01-7.47] vs. 7.27 [6.68-7.39], p = 0.02), and highest CRP levels were higher (112.5 mg/L [5.0-425.0] vs. 66.0 [5.2-189.0], p = 0.05) in PT-NEC vs. CHD-NEC. Anatomic localisation of the disease differed: the colon was significantly more often involved in CHD-NEC versus PT-NEC (86% vs. 33%, p = 0.03). Mortality caused by NEC was not different (22% vs. 11%, p = 0.47).

CONCLUSION

While outcome of NEC in both groups is similar, the predominant NEC localisation differed between CHD-NEC and PT-NEC patients. This suggests that both variants of the disease have a different underlying pathophysiological mechanism that predisposes different intestinal regions to develop NEC.

TYPE OF STUDY

Retrospective Case-Control Study.

LEVEL OF EVIDENCE

Level III.

Developing routinely recorded clinical data from electronic patient records as a national resource to improve neonatal health care: the Medicines for Neonates research programme

Background

Clinical data offer the potential to advance patient care. Neonatal specialised care is a high-cost NHS service received by approximately 80,000 newborn infants each year.

Objectives

(1) To develop the use of routinely recorded operational clinical data from electronic patient records (EPRs), secure national coverage, evaluate and improve the quality of clinical data, and develop their use as a national resource to improve neonatal health care and outcomes. To test the hypotheses that (2) clinical and research data are of comparable quality, (3) routine NHS clinical assessment at the age of 2 years reliably identifies children with neurodevelopmental impairment and (4) trial-based economic evaluations of neonatal interventions can be reliably conducted using clinical data. (5) To test methods to link NHS data sets and (6) to evaluate parent views of personal data in research.

Design

Six inter-related workstreams; quarterly extractions of predefined data from neonatal EPRs; and approvals from the National Research Ethics Service, Health Research Authority Confidentiality Advisory Group, Caldicott Guardians and lead neonatal clinicians of participating NHS trusts.

Setting

NHS neonatal units.

Participants

Neonatal clinical teams; parents of babies admitted to NHS neonatal units.

Interventions

In workstream 3, we employed the Bayley-III scales to evaluate neurodevelopmental status and the Quantitative Checklist of Autism in Toddlers (Q-CHAT) to evaluate social communication skills. In workstream 6, we recruited parents with previous experience of a child in neonatal care to assist in the design of a questionnaire directed at the parents of infants admitted to neonatal units.

Data sources

Data were extracted from the EPR of admissions to NHS neonatal units.

Main outcome measures

We created a National Neonatal Research Database (NNRD) containing a defined extract from real-time, point-of-care, clinician-entered EPRs from all NHS neonatal units in England, Wales and Scotland (n = 200), established a UK Neonatal Collaborative of all NHS trusts providing neonatal specialised care, and created a new NHS information standard: the Neonatal Data Set (ISB 1595) (see http://webarchive.nationalarchives.gov.uk/±/http://www.isb.nhs.uk/documents/isb-1595/amd-32–2012/index_html; accessed 25 June 2018).

Results

We found low discordance between clinical (NNRD) and research data for most important infant and maternal characteristics, and higher prevalence of clinical outcomes. Compared with research assessments, NHS clinical assessment at the age of 2 years has lower sensitivity but higher specificity for identifying children with neurodevelopmental impairment. Completeness and quality are higher for clinical than for administrative NHS data; linkage is feasible and substantially enhances data quality and scope. The majority of hospital resource inputs for economic evaluations of neonatal interventions can be extracted reliably from the NNRD. In general, there is strong parent support for sharing routine clinical data for research purposes.

Limitations

We were only able to include data from all English neonatal units from 2012 onwards and conduct only limited cross validation of NNRD data directly against data in paper case notes. We were unable to conduct qualitative analyses of parent perspectives. We were also only able to assess the utility of trial-based economic evaluations of neonatal interventions using a single trial. We suggest that results should be validated against other trials.

Conclusions

We show that it is possible to obtain research-standard data from neonatal EPRs, and achieve complete population coverage, but we highlight the importance of implementing systematic examination of NHS data quality and completeness and testing methods to improve these measures. Currently available EPR data do not enable ascertainment of neurodevelopmental outcomes reliably in very preterm infants. Measures to maintain high quality and completeness of clinical and administrative data are important health service goals. As parent support for sharing clinical data for research is underpinned by strong altruistic motivation, improving wider public understanding of benefits may enhance informed decision-making.

Future work

We aim to implement a new paradigm for newborn health care in which continuous incremental improvement is achieved efficiently and cost-effectively by close integration of evidence generation with clinical care through the use of high-quality EPR data. In future work, we aim to automate completeness and quality checks and make recording processes more ‘user friendly’ and constructed in ways that minimise the likelihood of missing or erroneous entries. The development of criteria that provide assurance that data conform to prespecified completeness and quality criteria would be an important development. The benefits of EPR data might be extended by testing their use in large pragmatic clinical trials. It would also be of value to develop methods to quality assure EPR data including involving parents, and link the NNRD to other health, social care and educational data sets to facilitate the acquisition of lifelong outcomes across multiple domains.

Study registration

This study is registered as PROSPERO CRD42015017439 (workstream 1) and PROSPERO CRD42012002168 (workstream 3).

Funding

The National Institute for Health Research Programme Grants for Applied Research programme (£1,641,471). Unrestricted donations were supplied by Abbott Laboratories (Maidenhead, UK: £35,000), Nutricia Research Foundation (Schiphol, the Netherlands: £15,000), GE Healthcare (Amersham, UK: £1000). A grant to support the use of routinely collected, standardised, electronic clinical data for audit, management and multidisciplinary feedback in neonatal medicine was received from the Department of Health and Social Care (£135,494).

Application of abdominal sonography in diagnosis of infants with necrotizing enterocolitis

The purpose of this study was to explore the diagnostic significance of abdominal sonography (AUS) in infants with Necrotizing enterocolitis (NEC) admitted to a neonatal intensive care unit to better evaluate the ability of AUS to differentiate necrotizing enterocolitis from other intestinal diseases.All patients diagnosed with NEC at the Department of General Surgery and Neonatal Surgery, Qilu Children's Hospital between 1st, Jun, 2010 and 30th, Dec, 2015. The logistic regression analysis and the area under receiver operating characteristic (ROC) curve (AUCs) were also used to identify the sonographic factors for diagnosing NEC.For the entire cohort of 91 patients, we divided these patients into suspected NEC (n = 35) group and definite NEC (n = 56) group. After adjusting for competing sonographic factors, we identified that thick bowel wall (more than 2.5 mm) (P = .013, OR: 1.246), intramural gas (pneumatosis intestinalis) (P = .002, OR:1.983), portal venous gas (P = .022, OR:1.655) and reduced peristalsis (P = .011, OR:1.667) were independent diagnostic factors associated with NEC. We built a logistic model to diagnose NEC according to the results of multivariable logistic regression analysis. We found the AUROC for thick bowel wall (more than 2.5 mm), intramural gas (pneumatosis intestinalis), portal venous gas and reduced peristalsis were significantly lower than the AUROC for the logistic model was 0.841 (95% CI: 0.669 to 0.946).We found that thick bowel wall (more than 2.5 mm), intramural gas (pneumatosis intestinalis), portal venous gas and reduced peristalsis were independent diagnostic factors associated with NEC. The logistic model was significantly superior to the single sonographic parameter for diagnosing NEC.

Recent Potential Noninvasive Biomarkers in Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a rare but devastating gastrointestinal disease that predominately affects preterm neonates. Numerous studies have revealed that NEC is strongly associated with very low birth weight, degree of prematurity, formula feeding, infection, hypoxic/ischemic injury, and enteric dysbiosis. Given these clinical associations, the search for a deeper understanding of disease pathogenesis has led to an intense interest in the discovery and development of noninvasive biomarkers of NEC from stool, urine, and serum. Biomarkers for NEC may serve at least two general purposes of urgent unmet need: to improve diagnostic accuracy and disease prediction and to reveal the mechanism of the disease. This review will provide an overview of recent research focused on clinical NEC and highlight the advances that were made within the past five years towards the development of noninvasive diagnostic biomarkers.

Maternal, fetal and perinatal factors associated with necrotizing enterocolitis in Sweden. A national case-control study

OBJECTIVE

To analyze associations of maternal, fetal, gestational, and perinatal factors with necrotizing enterocolitis in a matched case-control study based on routinely collected, nationwide register data.

STUDY DESIGN

All infants born in 1987 through 2009 with a diagnosis of necrotizing enterocolitis in any of the Swedish national health care registers were identified. For each case up to 6 controls, matched for birth year and gestational age, were selected. The resulting study population consisted of 720 cases and 3,567 controls. Information on socioeconomic data about the mother, maternal morbidity, pregnancy related diagnoses, perinatal diagnoses of the infant, and procedures in the perinatal period, was obtained for all cases and controls and analyzed with univariable and multivariable logistic regressions for the whole study population as well as for subgroups according to gestational age.

RESULTS

In the study population as a whole, we found independent positive associations with necrotizing enterocolitis for isoimmunization, fetal distress, cesarean section, neonatal bacterial infection including sepsis, erythrocyte transfusion, persistent ductus arteriosus, cardiac malformation, gastrointestinal malformation, and chromosomal abnormality. Negative associations were found for maternal weight, preeclampsia, maternal urinary infection, premature rupture of the membranes, and birthweight. Different patterns of associations were seen in the subgroups of different gestational age.

CONCLUSION

With some interesting exceptions, especially in negative associations, the results of this large, population based study, are in keeping with earlier studies. Although restrained by the limitations of register data, the findings mirror conceivable pathophysiological processes and underline that NEC is a multifactorial disease.

Infections following surgical patent ductus arteriosus ligation in very-low-birthweight neonates

BACKGROUND

Very-low-birthweight (VLBW) neonates (<1500g) comprise approximately 1% of liveborn infants in Poland. Patent ductus arteriosus (PDA) is a common complication of prematurity. This study aimed to determine how many VLBW neonates treated in the participating units needed surgical correction of PDA, and to evaluate the incidence of various types of postoperative infections and their microbiology.

METHODS

Observational study in five neonatology departments by the Polish Neonatology Surveillance Network, involving 2039 VLBW newborns of whom 103 (5.1%) required surgical PDA ligation. Continuous infection surveillance was conducted between 2009 and 2013; infections were defined based on Gastmeier's criteria.

RESULTS

PDA surgery was required significantly more frequently in infants from multiple pregnancies, and where labour was complicated by amnionitis. Surgical PDA correction was performed, on average, at 19 days of life. The incidence of infection was 48.5% (N = 50), and the most common infections were bloodstream infection (26.2%) and pneumonia (22.3%). A correlation was observed between the day on which the procedure was performed and the time of infection: the earlier the neonate underwent PDA surgery, the earlier the infection manifested (P = 0.032). A high CRIB score and chorioamnionitis contributed significantly to the presence of infection.

CONCLUSION

The later the PDA surgery was performed, the later the infection occurred. The incidence of infection after correction of PDA among VLBW neonates was comparable with the incidence of infection among all hospitalized VLBW neonates.

Postoperative characteristics of infants who developed necrotizing enterocolitis with different postnatal ages

Our goal was to investigate the surgical procedures, postoperative complications, and survival with regard to different onset timing of necrotizing enterocolitis (NEC).We performed a retrospective review of medical records with a diagnosis of NEC between 2005 and 2016. The cutoff was set at 10 days for early onset ≤10 days and late onset over 10 days. Propensity score matching was performed to adjust for any baseline differences. In 53 paired patients, clinical outcomes, including, mortality, postoperative complications, and length of neonatal intensive care unit (NICU) stay, were evaluated on the basis of early or late-onset NEC.Successful 1:1 matching propensity score matching was performed with 208 infants. Mortality for early-onset NEC infants was lower than that of early late NEC infants (P = .026). A lower overall postoperative complication rate, including infectious complications [19 (35.8) vs 29 (54.7); odds ratio, 0.462, confidence interval (CI) 0.212-1.008, P = .039], was noted in patients with early-onset NEC compared with infants with late-onset NEC. NICU stay and major complication were marginal different between the 2 groups. Comparison of feeding outcomes revealed that the time to achieve full enteral feeds was significantly longer for those with late-onset NEC (18.1 ± 11.5 vs 26.3 ± 15.6, P = .008).The infants who develop NEC after 10 days of life do influence postoperative outcome survival or other clinically important outcomes after laparotomy.

Population-based study showed that necrotising enterocolitis occurred in space-time clusters with a decreasing secular trend in Sweden

Aim

This study investigated space–time clustering of neonatal necrotising enterocolitis over three decades.

Methods

Space–time clustering analyses objects that are grouped by a specific place and time. The Knox test and Kulldorff's scan statistic were used to analyse space–time clusters in 808 children diagnosed with necrotising enterocolitis in a national cohort of 2 389 681 children born between 1987 and 2009 in Sweden. The municipality the mother lived in and the delivery hospital defined closeness in space and the time between when the cases were born – seven, 14 and 21 days – defined closeness in time.

Results

The Knox test showed no indication of space–time clustering at the residential level, but clear indications at the hospital level in all the time windows: seven days (p = 0.026), 14 days (p = 0.010) and 21 days (p = 0.004). Significant clustering at the hospital level was found during 1987–1997, but not during 1998–2009. Kulldorff's scan statistic found seven significant clusters at the hospital level.

Conclusion

Space–time clustering was found at the hospital but not residential level, suggesting a contagious environmental effect after delivery, but not in the prenatal period. The decrease in clustering over time may reflect improved routines to minimise the risk of contagion between patients receiving neonatal care.

Gastrointestinal Organoids: Understanding the Molecular Basis of the Host-Microbe Interface

In recent years, increasing attention has been devoted to the concept that microorganisms play an integral role in human physiology and pathophysiology. Despite this, the molecular basis of host-pathogen and host-symbiont interactions in the human intestine remains poorly understood owing to the limited availability of human tissue, and the biological complexity of host-microbe interactions. Over the past decade, technological advances have enabled long-term culture of organotypic intestinal tissue derived from human subjects and from human pluripotent stem cells, and these in vitro culture systems already have shown the potential to inform our understanding significantly of host-microbe interactions. Gastrointestinal organoids represent a substantial advance in structural and functional complexity over traditional in vitro cell culture models of the human gastrointestinal epithelium while retaining much of the genetic and molecular tractability that makes in vitro experimentation so appealing. The opportunity to model epithelial barrier dynamics, cellular differentiation, and proliferation more accurately in specific intestinal segments and in tissue containing a proportional representation of the diverse epithelial subtypes found in the native gut greatly enhances the translational potential of organotypic gastrointestinal culture systems. By using these tools, researchers have uncovered novel aspects of host-pathogen and host-symbiont interactions with the intestinal epithelium. Application of these tools promises to reveal new insights into the pathogenesis of infectious disease, inflammation, cancer, and the role of microorganisms in intestinal development. This review summarizes research on the use of gastrointestinal organoids as a model of the host-microbe interface.

Surgical necrotizing enterocolitis

Although currently available data are variable, it appears that the incidence of surgical necrotizing enterocolitis (NEC) has not decreased significantly over the past decade. Pneumoperitoneum and clinical deterioration despite maximal medical therapy remain the most common indications for operative treatment. Robust studies linking outcomes with specific indications for operation are lacking. Promising biomarkers for severe NEC include fecal calprotectin and S100A12; serum fatty acid-binding protein; and urine biomarkers. Recent advances in ultrasonography make this imaging modality more useful in identifying surgical NEC and near-infrared spectroscopy (NIRS) is being actively studied. Another fairly recent finding is that regionalization of care for infants with NEC likely improves outcomes. The neurodevelopmental outcomes after surgical treatment are known to be poor. A randomized trial near completion will provide robust data regarding neurodevelopmental outcomes after laparotomy versus drainage as the initial operative treatment for severe NEC.

Current Knowledge of Necrotizing Enterocolitis in Preterm Infants and the Impact of Different Types of Enteral Nutrition Products

Preterm infants are extremely vulnerable to a range of morbidities and mortality. Underdeveloped cardiac, respiratory, gastrointestinal, and immune systems in the preterm period increase the risk of necrotizing enterocolitis (NEC), a serious disease of the gut. NEC affects 5-12% of very-low birth-weight infants, leads to surgery in 20-40% of cases, and is fatal in 25-50% of cases. There are multiple factors that may contribute to NEC, but the exact cause is not yet fully understood. Severe cases can result in intestinal resection or death, and the health care costs average >$300,000/infant when surgical management is required. Different types of nutrition may affect the onset or progression of NEC. Several studies have indicated that bovine milk-based infant formulas lead to a higher incidence of NEC in preterm infants than does human milk (HM). However, it is not clear why HM is linked to a lower incidence of NEC or why some infants fed an exclusively HM diet still develop NEC. An area that has not been thoroughly explored is the use of semielemental or elemental formulas. These specialty formulas are easy to digest and absorb in the gut and may be an effective nutritional intervention for reducing the risk of NEC. This review summarizes what is known about the factors that contribute to the onset and progression of NEC, discusses its health care cost implications, and explores the impact that different formulas and HM have on this disease.

[Analysis of population characteristics of infants affected by necrotizing enterocolitis in a tertiary centre in the last 12 years]

BACKGROUND

Necrotizing enterocolitis is the most lethal gastrointestinal emergency in the neonatal period. Incidence and mortality have remained stable in recent years despite advances in neonatal intensive care. The aim of this study is to show the general characteristics of patients diagnosed with necrotizing enterocolitis at Teresa Herrera's Hospital (La Coruna, Spain) in the last 12years.

MATERIAL AND METHODS

This study makes a retrospective and prospective descriptive analysis, evaluating the medical records and collecting radiological demographic variables, gestational data, perinatal history, clinical, analytical and perinatal therapeutic management and events in patients diagnosed with and treated for necrotizing enterocolitis between 2003 and 2015.

RESULTS

A total of 124 patients met the criteria for inclusion in the study. The mean gestational age of our patients was 33 weeks and remained stable compared with other studies. The average weight of our patients was 1,873g. In our series of cases there was a progressive and significant increase in maternal age and the rate of artificial pregnancies and multiple births. In our series 38.7% of our patients required surgical treatment and the fatality rate was 11.4%.

DISCUSSION

Despite advances in pre- and perinatal care necrotizing enterocolitis represents the leading cause of premature mortality. Incidence has remained unchanged in recent decades. More studies are required to identify both, risk and protective factors to reduce the morbidity and mortality of this entity.

Incidence and enteral feed antecedents of severe neonatal necrotising enterocolitis across neonatal networks in England, 2012-13: a whole-population surveillance study

BACKGROUND

Necrotising enterocolitis is a neonatal gastrointestinal inflammatory disease with high mortality and severe morbidity. This disorder is growing in global relevance as birth rates and survival of babies with low gestational age improve. Population data are scant and pathogenesis is incompletely understood, but enteral feed exposures are believed to affect risk. We aimed to quantify the national incidence of severe necrotising enterocolitis, describe variation across neonatal networks, and investigate enteral feeding-related antecedents of severe necrotising enterocolitis.

METHODS

We undertook a 2-year national surveillance study (the UK Neonatal Collaborative Necrotising Enterocolitis [UKNC-NEC] Study) of babies born in England to quantify the burden of severe or fatal necrotising enterocolitis confirmed by laparotomy, leading to death, or both. Data on all liveborn babies admitted to neonatal units between Jan 1, 2012, and Dec 31, 2013, were obtained from the National Neonatal Research Database. In the subgroup of babies born before a gestational age of 32 weeks, we did a propensity score analysis of the effect of feeding in the first 14 postnatal days with own mother's milk, with or without human donor milk and avoidance of bovine-origin formula, or milk fortifier, on the risk of developing necrotising enterocolitis.

FINDINGS

During the study period, 118 073 babies were admitted to 163 neonatal units across 23 networks, of whom 14 678 were born before a gestational age of 32 weeks. Overall, 531 (0·4%) babies developed severe necrotising enterocolitis, of whom 247 (46·5%) died (139 after laparotomy). 462 (3·2%) of 14 678 babies born before a gestational age of 32 weeks developed severe necrotising enterocolitis, of whom 222 (48·1%) died. Among babies born before a gestational age of 32 weeks, the adjusted network incidence of necrotising enterocolitis ranged from 2·51% (95% CI 1·13-3·60) to 3·85% (2·37-5·33), with no unusual variation from the adjusted national incidence of 3·13% (2·85-3·42), despite variation in feeding practices. The absolute risk difference for babies born before a gestational age of 32 weeks who received their own mother's milk within 7 days of birth was -0·88% (95% CI -1·15 to -0·61; relative risk 0·69, 95% CI 0·60 to 0·78; number needed to treat to prevent one case of necrotising enterocolitis 114, 95% CI 87 to 136). For babies who received no compared with any bovine-origin products within 14 days of birth, the absolute risk difference was -0·65% (-1·01 to -0·29; relative risk 0·61, 0·39 to 0·83; number needed to treat 154, 99 to 345). We were unable to assess the effect of human donor milk as use was low.

INTERPRETATION

Early feeding of babies with their own mother's milk and avoidance of bovine-origin products might reduce the risk of necrotising enterocolitis, but the absolute reduction is small. Owing to the rarity of severe necrotising enterocolitis, international collaborations are needed for adequately powered preventive trials.

FUNDING

National Institute for Health Research.

Necrotizing enterocolitis: new insights into pathogenesis and mechanisms

Necrotizing enterocolitis (NEC) is the most frequent and lethal disease of the gastrointestinal tract of preterm infants. At present, NEC is thought to develop in the premature host in the setting of bacterial colonization, often after administration of non-breast milk feeds, and disease onset is thought to be due in part to a baseline increased reactivity of the premature intestinal mucosa to microbial ligands as compared with the full-term intestinal mucosa. The increased reactivity leads to mucosal destruction and impaired mesenteric perfusion and partly reflects an increased expression of the bacterial receptor Toll-like receptor 4 (TLR4) in the premature gut, as well as other factors that predispose the intestine to a hyper-reactive state in response to colonizing microorganisms. The increased expression of TLR4 in the premature gut reflects a surprising role for this molecule in the regulation of normal intestinal development through its effects on the Notch signalling pathway. This Review will examine the current approach to the diagnosis and treatment of NEC, provide an overview of our current knowledge regarding its molecular underpinnings and highlight advances made within the past decade towards the development of specific preventive and treatment strategies for this devastating disease.

Enteral paracetamol or Intravenous Indomethacin for Closure of Patent Ductus Arteriosus in Preterm Neonates: A Randomized Controlled Trial

OBJECTIVE

To compare the efficacy of enteral paracetamol and intravenous indomethacin for closure of patent ductus arteriosus (PDA) in preterm neonates.

DESIGN

Randomized controlled trial.

SETTING

Level III neonatal intensive care unit.

PARTICIPANTS

77 preterm neonates with birth weight ?1500 g and PDA size ?1.5 mm, with left to right ductal flow with left atrium to aortic root ratio >1.5:1; diagnosed by 2D-Echo within first 48 hours of life.

INTERVENTION

Paracetamol drops through the infant feeding tube (15 mg/kg/dose 6 hourly for 7 days) or intravenous indomethacin (0.2 mg/kg/dose once daily for 3 days).

OUTCOME MEASURES

Primary: PDA closure rate assessed by echocardiography. Secondary: need for surgical closure of PDA, renal impairment, gastrointestinal bleed, necrotising enterocolitis, hepatotoxicity, pulmonary hemorrhage, sepsis, hypothermia, retinopathy of prematurity, intraventricular hemorrhage, bronchopulmonary dysplasia and mortality.

RESULTS

PDA closure rate was 100% (36/36) in enteral paracetamol group as compared to 94.6% (35/37) in intravenous indomethacin group (P=0.13). The secondary outcomes were also similar between the two groups. There was no occurrence of hepatotoxicity.

CONCLUSIONS

Enteral paracetamol is safe but not superior to intravenous indomethacin in the treatment of PDA in preterm neonates.

The protective and anti-inflammatory effects of glucagon-like peptide-2 in an experimental rat model of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal disease, that affects premature infants. Glucagon-like peptide-2 (GLP-2) is an intestinotrophic hormone and reduces the inflammation. We suspected that GLP-2 would have protective and anti-inflammatory effects in an experimental rat model of NEC. NEC was induced in newborn rats by enteral feeding with hyperosmolar formula, asphyxial stress and enteral administration of lipopolysaccharide (LPS). Rats were randomly divided into the following four groups: dam-fed, NEC, NEC+GLP-2(L) given 80 μg/kg/day of GLP-2, and NEC+GLP-2(H) given 800 μg/kg/day of GLP-2. GLP-2 was administered subcutaneously every 6 h before stress. All animals surviving beyond 96 h or any that developed signs of distress were euthanized. The clinical sickness score in the NEC+GLP-2(H) group was significantly lower than that in the NEC group. The NEC score and the survival rate in the NEC+GLP-2(H) group was significantly improved compared with those in the NEC and the NEC+GLP-2(L) groups. Villous height and crypt depth in both the GLP-2 treatment groups were significantly increased compared with those in the NEC group. There were no significant differences in the crypt cell proliferation indices among the groups. Ileal interstitial TNF-α and IL-6 level in the NEC+GLP-2(H) group was decreased to the same levels in the dam-fed group. High dose GLP-2 administration improved the incidence and survival rate for NEC. It also decreased mucosal inflammatory cytokine production. These results support a potential therapeutic role for GLP-2 in the treatment of NEC.

Necrotizing enterocolitis: controversies and challenges

Necrotizing enterocolitis is a devastating intestinal disease that affects ~5% of preterm neonates. Despite advancements in neonatal care, mortality remains high (30–50%) and controversy still persists with regards to the most appropriate management of neonates with necrotizing enterocolitis. Herein, we review some controversial aspects regarding the epidemiology, imaging, medical and surgical management of necrotizing enterocolitis and we describe new emerging strategies for prevention and treatment.

Reducing necrotizing enterocolitis in very low birth weight infants using quality-improvement methods

OBJECTIVE

Owing to a rise in necrotizing enterocolitis (NEC, stage ⩾ 2) among very low birth weight (VLBW, birth weight <1500 g) infants from 4% in 2005 to 2006 to 10% in 2007 to 2008, we developed and implemented quality improvement (QI) initiatives. The objective was to evaluate the impact of QI initiatives on NEC incidence in VLBW infants.

STUDY DESIGN

In September 2009, we developed an NEC QI multidisciplinary team that conducted literature reviews and reviewed practices from other institutions to develop a feeding protocol, which was implemented in December 2009. The team tracked intervention compliance and occurrence of NEC stage ⩾ 2. In May 2010, we reviewed our nasogastric tube practice and relevant literature to develop a second intervention that reduced nasogastric tube indwelling time. The infants were divided into three groups: baseline (January 2008 to Novovember 2009, n219), QI phase 1 (December 2009 to May 2010, n62) and QI phase 2 (June 2010 to November 2011, n170).

RESULT

The NEC incidence did not decrease after implementation of the feeding protocol in QI phase 1 (19.4%) but did decline significantly after changing nasogastric tube management in QI phase 2 (2.9%). Multivariable logistic regression analysis demonstrated a significant relationship between QI phase and the incidence of NEC.

CONCLUSION

QI initiatives were effective in decreasing NEC incidence in our high human milk-feeding NICU. Nasogastric tube bacterial contamination may have contributed to our peak in NEC incidence.

The outcome of critically ill neonates undergoing laparotomy for necrotising enterocolitis in the neonatal intensive care unit: a 10-year review

PURPOSE

To evaluate outcomes in critically ill neonates with necrotising enterocolitis (NEC) undergoing a laparotomy in the neonatal intensive care unit (NICU).

METHODS

This is a retrospective review of neonates diagnosed with NEC who underwent a laparotomy on NICU between 2001 and 2011. Demographic, diagnostic, operative and outcome data were analysed. Nonparametric comparison was used. Data are reported as median (range).

RESULTS

221 infants with NEC were referred for surgical evaluation; 182 (82%) underwent surgery; 15 (8%) required a laparotomy on NICU. Five had NEC totalis, 4 multifocal disease and 6 focal disease. Five had an open and close laparotomy, 8 stoma with/without bowel resection and 2 bowel resection and primary anastomosis. Ten (67%) died at a median of 6.5-hours (2-72) postoperatively; 2 died at 72 and 264-days. The 30-day mortality rate was higher (p=0.01) among infants undergoing a laparotomy on NICU (10/15; 67%) than in theatre (54/167; 32%). There was no significant difference in mean Paediatric Index of Mortality 2 Scores between survivors and nonsurvivors (p=0.55). Three (20%) infants remain alive with no or minimal disability at 1.4 (0.5-7.5) years.

CONCLUSION

Laparotomy for NEC on NICU is a treatment option for neonates who are too unstable to transfer to theatre. However, with 67% dying within 6.5-hours and a further 13% after months in hospital, we must consider whether surgery is always in their best interests. Development of a prediction model to help distinguish those at highest risk of long-term morbidity and mortality could help with decision making in this difficult situation.

Intestinal alkaline phosphatase is protective to the preterm rat pup intestine

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common surgical emergency in neonates, with a mortality rate between 10 and 50%. The onset of necrotizing enterocolitis is highly variable and associated with numerous risk factors. Prior research has shown that enteral supplementation with intestinal alkaline phosphatase (IAP) decreases the severity of NEC. The aim of this study is to investigate whether IAP is protective to the preterm intestine in the presence of formula feeding and in the absence of NEC.

METHODS

Preterm rat pups were fed formula with or without supplementation with IAP, and intestine was obtained on day of life 3 for analysis of IAP activity, mRNA expression of TNFα, IL-6 and iNOS and permeability and cytokine expression after LPS exposure.

RESULTS

There was no difference in the absolute and intestine specific alkaline phosphatase activity in both groups. Rat pups fed IAP had decreased mRNA expression of the inflammatory cytokines TNFα, IL-6 and iNOS. Pups supplemented with IAP had decreased permeability and inflammatory cytokine expression after exposure to LPS ex vivo when compared to formula fed controls.

CONCLUSIONS

Our results support that IAP is beneficial to preterm intestine and decreases intestinal injury and inflammation caused by LPS.