Diabetes mellitus in pregnancy across Canada

BACKGROUND

Contemporary estimates of diabetes mellitus (DM) rates in pregnancy are lacking in Canada. Accordingly, this study examined trends in the rates of type 1 (T1DM), type 2 (T2DM) and gestational (GDM) DM in Canada over a 15-year period, and selected adverse pregnancy outcomes.

METHODS

This study used repeated cross-sectional data from the Canadian Institute of Health Information (CIHI) hospitalization discharge abstract database (DAD). Maternal delivery records were linked to their respective birth records from 2006 to 2019. The prevalence of T1DM, T2DM and GDM were calculated, including relative changes over time, assessed by a Cochrane-Armitage test. Also assessed were differences between provinces and territories in the prevalence of DM.

RESULTS

Over the 15-year study period, comprising 4,320,778 hospital deliveries in Canada, there was a statistically significant increase in the prevalence of GDM and T1DM and T2DM. Compared to pregnancies without DM, all pregnancies with any form of DM had higher rates of hypertension and Caesarian delivery, and also adverse infant outcomes, including major congenital anomalies, preterm birth and large-for-gestational age birthweight.

CONCLUSION

Among 4.3 million pregnancies in Canada, there has been a rise in the prevalence of DM. T2DM and GDM are expected to increase further as more overweight women conceive in Canada.

Severity and duration of dysglycemia and brain injury among patients with neonatal encephalopathy

Background

Evidence is needed to inform thresholds for glycemic management in neonatal encephalopathy (NE). We investigated how severity and duration of dysglycemia relate to brain injury after NE.

Methods

A prospective cohort of 108 neonates ≥36 weeks gestational age with NE were enrolled between August 2014 and November 2019 at the Hospital for Sick Children, in Toronto, Canada. Participants underwent continuous glucose monitoring for 72 h, MRI at day 4 of life, and follow-up at 18 months. Receiver operating characteristic curves were used to assess the predictive value of glucose measures (minimum and maximum glucose, sequential 1 mmol/L glucose thresholds) during the first 72 h of life (HOL) for each brain injury pattern (basal ganglia, watershed, focal infarct, posterior-predominant). Linear and logistic regression analyses were used to assess the relationship between abnormal glycemia and 18-month outcomes (Bayley-III composite scores, Child Behavior Checklist [CBCL] T-scores, neuromotor score, cerebral palsy [CP], death), adjusting for brain injury severity.

Findings

Of 108 neonates enrolled, 102 (94%) had an MRI. Maximum glucose during the first 48 HOL best predicted basal ganglia (AUC = 0.811) and watershed (AUC = 0.858) injury. Minimum glucose was not predictive of brain injury (AUC <0.509). Ninety-one (89%) infants underwent follow-up assessments at 19.0 ± 1.7 months. A glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with 5.8-point higher CBCL Internalizing Composite T-score (P = 0.029), 0.3-point worse neuromotor score (P = 0.035), 8.6-fold higher odds for CP diagnosis (P = 0.014). While the glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with higher odds of the composite outcome of severe disability or death (OR 3.0, 95% CI 1.0-8.4, P = 0.042), it was not associated with the composite outcome of moderate-to-severe disability or death (OR 0.9, 95% CI 0.4-2.2, P = 0.801). All associations with outcome lost significance after adjusting for brain injury severity.

Interpretation

Maximum glucose concentration in the first 48 HOL is predictive of brain injury after NE. Further trials are needed to assess if protocols to control maximum glucose concentrations improve outcomes after NE.

Funding

Canadian Institutes for Health Research, National Institutes of Health, and SickKids Foundation.

Les tests et le dépistage génétiques chez les enfants

Les tests génétiques, qui ont évolué rapidement depuis vingt ans, deviennent monnaie courante en pédiatrie. Le présent document de principes procure un aperçu des récents développements qui peuvent avoir des répercussions sur les tests génétiques chez les enfants. La génétique est un domaine en constante évolution, et le présent document de principes s'attarde tout particulièrement au dépistage néonatal élargi, au séquençage de nouvelle génération, aux découvertes fortuites, aux tests commercialisés directement auprès des consommateurs, aux tests d'histocompatibilité et aux tests génétiques dans le contexte de la recherche.

Genetic testing and screening in children

Genetic testing has progressed rapidly over the past two decades and is becoming common in paediatrics. This statement provides an overview of recent developments that may impact genetic testing in children. Genetics is a rapidly evolving field, and this statement focuses specifically on expanded newborn screening, next generation sequencing (NGS), incidental findings, direct-to-consumer testing, histocompatibility testing, and genetic testing in a research context.

Risk factors for prolonged mechanical ventilation in neonates following gastrointestinal surgery

BACKGROUND

Prolonged mechanical ventilation (MV) should be avoided in neonates. Noninvasive ventilation (NIV) can facilitate weaning from MV but has risks for patients immediately following foregut surgery due to the potential risk of anastomotic leak. We evaluated the risk factors for prolonged MV following intestinal surgery in neonates.

METHODS

We retrospectively reviewed 253 neonates undergoing intestinal surgery in 2017-2018 to identify risk factors for prolonged MV, and determine the correlation between NIV and anastomotic leak in a tertiary neonatal intensive care unit that performs the greatest number of neonatal surgeries in Ontario.

RESULTS

The most common diagnoses were necrotizing enterocolitis/spontaneous intestinal perforation (NEC/SIP) 21%, intestinal atresia 16%, esophageal atresia/tracheoesophageal fistula 14%, ano-rectal malformation 13%, malrotation/volvulus 11%, gastroschisis 9% and omphalocele 4%. The median (IQR) duration of MV post-surgery was 3 (1-8) days with 25.7 % (n=65) of neonates on MV for >7 days. Compared to infants on MV post-surgery for ≤7 days, those with MV>7 days were of lower gestational age, birth weight and weight at surgery, but a higher proportion underwent stoma creation, had a longer duration of opioid administration and higher rates of moderate to severe bronchopulmonary dysplasia (BPD) and mortality (P<0.05). Generalized linear regression analysis showed lower gestational age (GA) and longer opioid administration were associated with longer duration of MV (P<0.001), but indication for surgery, weight at surgery and stoma creation didn't correlate with longer duration of MV (P>0.05). Of the 122 patients handled by one-stage resection with primary anastomosis, 22.1% (n=27) received NIV with 74.1% (n=20) commenced on NIV after 7 days post-surgery, anastomotic leak was detected in 2.5 % (3/122) patients and didn't correlate with NIV.

CONCLUSIONS

Lower GA and longer opioid administration were risk factors for prolonged MV in neonates following intestinal surgery. Further research is needed to investigate modifiable practices around pain assessment/ventilation in these patients, and the correlation between NIV and anastomotic leak.

Hyperglycemia associated with acute brain injury in neonatal encephalopathy

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Cohort study of neonatal encephalopathy using continuous glucose monitoring.

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Higher glucose on day 1 associated with widespread changes in brain microstructure.

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Lower glucose not associated with brain microstructural changes.

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No changes in MR spectroscopy found related to higher or lower glucose.

Objective

To identify how alterations in glucose levels are associated with regional brain injury in neonatal encephalopathy.

Methods

This was a prospective cohort study of 102 newborns with neonatal encephalopathy, with continuous glucose monitoring for 72 h. 97 (95%) completed 72 h of therapeutic hypothermia. Brain imaging around day 5 of life included diffusion tensor imaging and MR spectroscopy. Regions of interest were placed for both DTI and MR spectroscopy, and tractography of the optic radiation and corticospinal tract were evaluated. Linear regression models related each MR metric with minimum and maximum glucose values during each day of life, adjusting for 5-minute Apgar scores and umbilical artery pH.

Results

Higher maximum glucose levels on the first day of life were associated with widespread changes in mean diffusivity in the anterior and posterior white matter, splenium of the corpus callosum, lentiform nucleus, pulvinar nucleus of the thalamus, posterior limb of the internal capsule, and optic radiations, thus including regions traditionally associated with hypoxia–ischemia or hypoglycemia. No associations were found between lower minimum glucose levels and DTI changes in any regions tested, or between glucose levels and MR spectroscopy.

Conclusions

In this cohort of neonatal encephalopathy with therapeutic hypothermia, higher maximal glucose on the first day of life was associated with widespread microstructural changes, but lower minimum glucose levels were not associated with changes in any of the regions tested. Long-term follow-up will determine if imaging findings translate to long-term outcomes.

Population-based surveillance of severe microcephaly and congenital Zika syndrome in Canada

PURPOSE

To estimate the minimum incidence of congenital Zika syndrome (CZS) and severe microcephaly in Canada and describe key clinical, epidemiological, aetiological and outcome features of these conditions.

METHODS

Two separate national surveillance studies were conducted on CZS and severe microcephaly using the well-established Canadian Paediatric Surveillance Program from 2016 to 2019. Over 2700 paediatricians across Canada were surveyed monthly and asked to report demographic details, pregnancy and travel history, infant anthropometry, clinical features and laboratory findings of newly identified cases. Reports were reviewed to assign an underlying aetiology of severe microcephaly. Incidence rates were estimated using monthly live birth denominators.

RESULTS

Thirty-four infants met the case definition for severe microcephaly and <5 met the case definition for CZS. The associated minimum incidence rates were 4.5 per 100 000 live births for severe microcephaly and 0.1-0.5 per 100 000 live births for CZS. Of severe microcephaly cases, 53% were attributed to genetic causes, 15% to infectious or ischaemic causes and 32% to unknown causes. The median head circumference-for-age Z-score at birth was -3.2 (IQR -3.8 to -2.6), and catch-up growth was often not achieved. Common clinical features included intracranial abnormalities (n=23), dysmorphology (n=19) and developmental delays (n=14). Mothers of infants with non-genetic aetiologies travelled during pregnancy more often (10/16) than mothers of infants with genetic aetiologies (<5/18; p<0.01).

CONCLUSION

Severe microcephaly and CZS are both rare in Canada. Minimum incidence rates can be used as a baseline against which novel or re-emergent causes of severe microcephaly or CZS can be compared.

Abnormalities in evoked potentials associated with abnormal glycemia and brain injury in neonatal hypoxic-ischemic encephalopathy

OBJECTIVE

To investigate how functional integrity of ascending sensory pathways measured by visual and somatosensory evoked potentials (VEP & SEP) is associated with abnormal glycemia and brain injury in newborns treated with hypothermia for hypoxic-ischemic encephalopathy (HIE).

METHODS

Fifty-four neonates ≥ 36 weeks gestational age with HIE underwent glucose testing, VEPs, SEPs, and magnetic resonance imaging (MRI) the first week of life. Minimum and maximum glucose values recorded prior to evoked potential (EP) testing were compared with VEP and SEP measures using generalized estimating equations. Relationships between VEP and SEP measures and brain injury on MRI were assessed.

RESULTS

Maximum glucose is associated with decreased P200 amplitude, and increased odds that N300 peak will be delayed/absent. Minimum glucose is associated with decreased P22 amplitude. Presence of P200 and N300 peaks is associated with decreased odds of brain injury in the visual processing pathway, with delayed/absent N300 peak associated with increased odds of brain injury in posterior white matter.

CONCLUSIONS

Deviations from normoglycemia are associated with abnormal EPs, and abnormal VEPs are associated with brain injury on MRI in cooled neonates with HIE.

SIGNIFICANCE

Glucose is a modifiable risk factor associated with atypical brain function in neonates with HIE despite hypothermia treatment.

Data Quality Assessment on Congenital Anomalies in Ontario, Canada

Background: Congenital anomalies (CAs) are a major cause of infant morbidity and mortality in Canada. Reliably identifying CAs is essential for CA surveillance and research. The main objective of this study was to assess the agreement of eight sentinel anomalies including: neural tube defects (NTD), orofacial clefts, limb deficiency defects (LDD), Down syndrome (DS), tetralogy of Fallot (TOF), gastroschisis (GS), hypoplastic left heart syndrome (HLHS) and transposition of great vessels (TGA) captured in the BORN Information System (BIS) database and the Canadian Institute for Health Information (CIHI) Discharge Abstract Database (DAD). Methods: Live birth and stillbirth records between the BIS and CIHI-DAD in the fiscal years of 2012-2013 to 2015-2016 were linked using 10 digit infant Ontario Health Insurance Plan (OHIP) numbers. Percent agreement and Kappa statistics were performed to assess the reliability (agreement) of CAs identified in the linked BIS and CIHI-DAD birth records. Then, further investigations were conducted on those CA cases identified in the CIHI-DAD only. Results: Kappa coefficients of the eight selected CAs between BIS ("Confirmed" or "Suspected" cases) and CIHI-DAD were 0.96 (95% CI: 0.93-0.98) for GS; 0.81 (95% CI: 0.78-0.83) for Orofacial clefts; 0.75 (95% CI: 0.72-0.77) for DS; 0.71 (95% CI: 0.65-0.77) for TOF; 0.62 (95% CI: 0.55-0.68) for TGA; 0.59 (95% CI: 0.49-0.68) for HLHS, 0.53 (95% CI: 0.46-0.60) for NTD-all; and 0.30 (95% CI: 0.23-0.37) for LDD. Conclusions: The degree of agreement varied among sentinel CAs identified between the BIS and CIHI. The potential reasons for discrepancies include incompleteness of capturing CAs using existing picklist values, especially for certain sub-types, incomplete neonatal special care data in the BIS, and differences between clinical diagnosis in the BIS and ICD-10-CA classification in the DAD. A future data abstraction study will be conducted to investigate the potential reasons for discrepancies of CA capture between two databases. This project helps quantify the quality of CA data collection in the BIS, enhances understanding of CA prevalence in Ontario and provides direction for future data quality improvement activities.

Gastrointestinal hemodynamic changes during therapeutic hypothermia and after rewarming in neonatal hypoxic-Ischemic encephalopathy

BACKGROUND

Hypoxic-ischemic encephalopathy (HIE) is associated with disturbances in visceral blood flow velocities. Therapeutic Hypothermia (TH) is a standard of care; however, its impact on gastrointestinal blood flow in infants with HIE is unknown. The objective of this study was to assess gastrointestinal (GI) blood flow and left ventricle output (LVO) in infants with hypoxic-ischemic encephalopathy during whole body TH and after rewarming.

METHODS

Serial echocardiography and Doppler evaluation of intestinal blood flow (celiac (CA) and superior mesenteric (SMA) arteries) were prospectively performed in a cohort of 20 newborn infants with HIE at 4 time points during hypothermia and after rewarming. Demographic, clinical and biochemical data were collected and analyzed for their relevance.

RESULTS

Median gestational age and birth weight was 40 weeks (37-41) and 3410 g (2190-4950) respectively. Celiac and mesenteric artery flow remained low during hypothermia and rose significantly after rewarming [peak systolic velocity in CA (0.63 m/s to 0.77 m/s, p = 0.004) and SMA (0.43 m/s to 0.55 m/s, p = 0.001)]. This increase was temporally associated with increased left ventricular output (106 ml/kg/min to 149 ml/kg/min, p < 0.0001). Median age to reach 25% of the feeds was 5 days (1-7 days). All patients survived.

CONCLUSIONS

CA and SMA blood flow velocity and LVO did not vary during hypothermia but rose after rewarming. This may suggest protective effect of therapeutic hypothermia on gastrointestinal system. The association of these physiological changes with neonatal outcome needs further assessment.

Outcomes of multi-gestational pregnancies affected by esophageal atresia - tracheoesophageal fistula

BACKGROUND

Contemporary outcomes of infants with esophageal atresia with or without tracheoesophageal fistula (EA/TEF) from multi-gestational pregnancies compared to those of singleton pregnancies have not been reported.

METHODS

A single-center retrospective review of EA/TEF patients born from 1999 to 2013 was performed. Patient demographics, gestational age (GA), birth weight, associated anomalies, requirement for gastrostomy tube and mortality were reviewed.

RESULTS

Singleton EA/TEF patients outnumbered those from multi-gestational pregnancies nearly 10:1 (214 vs 22 patients). EA/TEF patients from multi-gestational pregnancies were more likely to be premature (77% vs. 32%), have lower birth weight (mean 1766 g vs. 2695 g), have associated duodenal atresia (18% vs. 6%) and require gastrostomy tube (41% vs. 33%) for feeding challenges compared to EA/TEF singletons. Mortality was also significantly greater for multi-gestational EA/TEF patients compared to singleton EA/TEF patients (18% vs. 6%).

CONCLUSION

EA/TEF infants from multi-gestational pregnancies have greater clinical complexity and mortality than singleton EA/TEF patients. Parents of EA/TEF multi-gestational infants should be appropriately counseled and supported.

The ESC ACCA EAPCI EORP acute coronary syndrome ST-elevation myocardial infarction registry

Aims 

The Acute Cardiac Care Association (ACCA)–European Association of Percutaneous Coronary Intervention (EAPCI) Registry on ST-elevation myocardial infarction (STEMI) of the EurObservational programme (EORP) of the European Society of Cardiology (ESC) registry aimed to determine the current state of the use of reperfusion therapy in ESC member and ESC affiliated countries and the adherence to ESC STEMI guidelines in patients with STEMI.

Methods and results 

Between 1 January 2015 and 31 March 2018, a total of 11 462 patients admitted with an initial diagnosis of STEMI according to the 2012 ESC STEMI guidelines were enrolled. Individual patient data were collected across 196 centres and 29 countries. Among the centres, there were 136 percutaneous coronary intervention centres and 91 with cardiac surgery on-site. The majority of centres (129/196) were part of a STEMI network. The main objective of this study was to describe the demographic, clinical, and angiographic characteristics of patients with STEMI. Other objectives include to assess management patterns and in particular the current use of reperfusion therapies and to evaluate how recommendations of most recent STEMI European guidelines regarding reperfusion therapies and adjunctive pharmacological and non-pharmacological treatments are adopted in clinical practice and how their application can impact on patients’ outcomes. Patients will be followed for 1 year after admission.

Conclusion 

The ESC ACCA-EAPCI EORP ACS STEMI registry is an international registry of care and outcomes of patients hospitalized with STEMI. It will provide insights into the contemporary patient profile, management patterns, and 1-year outcome of patients with STEMI.

Hyperglycemia and Glucose Variability Are Associated with Worse Brain Function and Seizures in Neonatal Encephalopathy: A Prospective Cohort Study

OBJECTIVES

To investigate how glucose abnormalities correlate with brain function on amplitude-integrated electroencephalography (aEEG) in infants with neonatal encephalopathy.

STUDY DESIGN

Neonates born at full term with encephalopathy were enrolled within 6 hours of birth in a prospective cohort study at a pediatric academic referral hospital. Continuous interstitial glucose monitors and aEEG were placed soon after birth and continued for 3 days. Episodes of hypoglycemia (≤50 mg/dL; ≤2.8 mmol/L) and hyperglycemia (>144 mg/dL; >8.0 mmol/L) were identified. aEEG was classified in 6-hour epochs for 3 domains (background, sleep-wake cycling, electrographic seizures). Generalized estimating equations assessed the relationship of hypo- or hyperglycemia with aEEG findings, adjusting for clinical markers of hypoxia-ischemia (Apgar scores, umbilical artery pH, and base deficit).

RESULTS

Forty-five infants (gestational age 39.5 ± 1.4 weeks) were included (24 males). During aEEG monitoring, 16 episodes of hypoglycemia were detected (9 infants, median duration 77.5, maximum 220 minutes) and 18 episodes of hyperglycemia (13 infants, median duration 237.5, maximum 3125 minutes). Epochs of hypoglycemia were not associated with aEEG changes. Compared with epochs of normoglycemia, epochs of hyperglycemia were associated with worse aEEG background scores (B 1.120, 95% CI 0.501-1.738, P < .001), less sleep-wake cycling (B 0.587, 95% CI 0.417-0.757, P < .001) and more electrographic seizures (B 0.433, 95% CI 0.185-0.681, P = .001), after adjusting for hypoxia-ischemia severity.

CONCLUSIONS

In neonates with encephalopathy, epochs of hyperglycemia were temporally associated with worse global brain function and seizures, even after we adjusted for hypoxia-ischemia severity. Whether hyperglycemia causes neuronal injury or is simply a marker of severe brain injury requires further study.

Neurodevelopmental outcomes of infants with esophageal atresia and tracheoesophageal fistula

BACKGROUND

Esophageal atresia with or without tracheoesophageal fistula (EA/TEF) is a complex disorder, and most outcome data are confined to mortality and feeding-related morbidities. Our objective was to examine mortality, growth and neurodevelopmental outcomes in a large recent cohort of infants with EA/TEF.

METHODS

Single center study of EA/TEF infants referred from January 2000 to December 2015. Data collected included associated defects, neonatal morbidity and mortality and growth and neurodevelopmental outcomes at age 12-36months. Multiple regression analysis was used to determine variables associated with adverse outcome.

RESULTS

Of the 253 infants identified, 102 infants (40%) were preterm. Overall mortality was 8.3%, the majority from major cardiac malformations (p<0.001) Neurodevelopmental assessments (n=182) showed that 76% were within normal, while some delay was seen in 24%, most often in expressive and receptive language. Nine infants had hearing impairment and 5 had visual impairment. Gastrostomy tubes were required in 47 patients and 15% continued to have weight growth velocities less than the 10th centile. A number of specialist interventions were required, Speech/Language being frequent.

CONCLUSION

Mortality in EA/TEF is primarily related to concomitant anomalies, especially cardiac. Multidisciplinary follow up is important for early identification and intervention for growth failure and developmental delay.

TYPE OF STUDY

Retrospective study LEVEL OF EVIDENCE: Level II.

Neonatal oesophageal perforation: The role for non-operative management

AIM

Isolated oesophageal perforation in neonates is a rare but potentially life-threatening condition. Although management has historically been operative, conservative management (antibiotics, bowel rest, parenteral nutrition) is now more routinely used. The aim of this study was to evaluate the management of this condition in two large neonatal surgical centres.

METHODS

A retrospective cohort study was conducted for neonates admitted to The Hospital for Sick Children (Toronto, Canada) or The Royal Children's Hospital (Melbourne, Australia) with a diagnosis of oesophageal perforation, from 2006 to 2016. Patients with oesophageal atresia or tracheo-oesophageal fistula were excluded. Data were collected from chart review regarding demographics, clinical course, management and outcomes.

RESULTS

Eleven neonates with oesophageal perforation were identified over a 10-year period at the two centres. Median gestational age at birth was 25.3 weeks (interquartile range 24.2-28.8) and the majority (7/11, 64%) of neonates were extremely low birthweight. Diagnosis was made on day 1 of life for 9 of 11 (81%) neonates and was secondary to nasogastric tube insertion in 10 of 11 (91%) neonates. Only four (36%) neonates had symptomatic complications. All neonates were managed with bowel rest and intravenous antibiotics for a median of 7 days (interquartile range 7-10); two patients required operative intervention. Three neonates (27%) developed chronic lung disease and two (19%) died prior to discharge.

CONCLUSIONS

Oesophageal perforation is severe complication secondary to instrumentation of the upper gastrointestinal tract in neonates. Prompt and accurate diagnosis is crucial. Non-operative management is effective for the majority, though morbidity is common.

Cardiovascular Associations with Abnormal Brain Magnetic Resonance Imaging in Neonates with Hypoxic Ischemic Encephalopathy Undergoing Therapeutic Hypothermia and Rewarming

OBJECTIVE

This article compares hemodynamic characteristics of neonates with hypoxic ischemic encephalopathy (HIE) receiving therapeutic hypothermia (TH) with normal versus abnormal brain magnetic resonance imaging (MRI).

METHODS

Serial echocardiography (echo) was performed within 24 hours, after 48 to 72 hours of cooling, within 24 hours of normothermia, and after starting feeds. Pulmonary hemodynamics, cardiac output, and ventricular function were evaluated. All neonates underwent brain MRI (day 4-5), per clinical standard of care. Clinical cardiovascular and echocardiography characteristics were compared between patients with normal versus abnormal MRI. Cardiovascular changes during TH and after rewarming were identified.

RESULTS

Twenty neonates at median gestation and birth weight of 40 weeks (interquartile range [IQR]: 39, 41) and 3,410 g (IQR: 2,885, 4,093), respectively, were enrolled. Increased median left ventricular output (LVO) (106-159 mL/kg/min, p < 0.001) and reduced isovolumic relaxation time (IVRT) (48-42 ms, p < 0.001) were seen after rewarming. Echocardiography evidence of pulmonary hypertension (PH) was identified in five neonates. Eight neonates (40%) had brain injury identified on MRI (watershed [n = 4], basal ganglia [n = 4]); this subgroup were more likely to have echo evidence of PH at 24 hours.

CONCLUSION

Longitudinal changes in cardiac output were noted in neonates with HIE during TH and rewarming. Echocardiography evidence of PH, however, was associated with abnormal MRI brain. The prognostic relevance of these physiologic changes requires more comprehensive delineation.

Adverse childhood experiences: Basics for the paediatrician

In 1998, the Centers for Disease Control and Prevention Adverse Childhood Experiences study established the profound effects of early childhood adversity on life course health. The burden of cumulative adversities can affect gene expression, immune system development and condition stress response. A scientific framework provides explanation for numerous childhood and adult health problems and high-risk behaviours that originate in early life. In our review, we discuss adverse childhood experiences, toxic stress, the neurobiological basis and multigenerational and epigenetic transmission of trauma and recognized health implications. Further, we outline building resilience, screening in the clinical setting, primary care interventions, applying trauma-informed care and future directions. We foresee that enhancing knowledge of the far-reaching effects of adverse childhood events will facilitate mitigation of toxic stress, promote child and family resilience and optimize life course health trajectories.

Early life environment and social determinants of cardiac health in children with congenital heart disease

Congenital heart disease is a significant cause of infant mortality. Epidemiology and social context play a crucial role in conditioning disease burden and modulating outcomes, while diagnosis and treatment remain resource intensive. This review will address the role of social demographics, environmental exposure, epigenetics and nutrition in the aetiology of congenital heart disease. We then discuss the determinant effect of social factors on the provision and outcomes of care for congenital heart disease and implications for practice. It is our hope that enhanced knowledge of the intersection of social determinants of health and congenital heart disease will facilitate effective preventative strategies at the individual and population levels to optimize heart health outcomes across the life course.

Enzyme replacement therapy in perinatal hypophosphatasia: Case report of a negative outcome and lessons for clinical practice

Enzyme replacement therapy (ERT) is a newly approved disease-modifying treatment for hypophosphatasia (HPP), a rare metabolic bone disorder. With an orphan drug and ultra-rare disease, sharing information about responders and non-responders is particularly important, as any one centre's familiarity with its use will be limited. Nearly all published data in infants and very young children with life-threatening HPP are from three small clinical trials that have reported generally positive outcomes. We describe in detail a patient with perinatal HPP for whom treatment with ERT was not successful. Lessons learned from this case can inform clinical decision-making and provide topics for the research agenda. We also discuss practical and ethical challenges related to treatment of an ultra-rare disease with an expensive new medication in a publicly funded healthcare system.

The Role of Interleukin-6 and Interleukin-8 Circulating Cytokines in Differentiating between Feeding Intolerance and Necrotizing Enterocolitis in Preterm Infants

Objective To describe the circulating levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-8 in stable premature infants, infants with suspect necrotizing enterocolitis (NEC)/feeding intolerance (FI), and infants with proven NEC and to determine whether combinations of markers could provide a diagnostic tool for differentiating between benign FI and NEC.

Methods Seventy infants were enrolled in a prospective study performed in two university neonatal intensive care units. Thirty-five matched controls (CON), 23 infants with FI or suspect NEC, and 12 infants with definitive and surgical NEC were studied. The pro-inflammatory cytokine (TNF-α, IL-6, and IL-8) levels were measured at the onset of FI or NEC, or during week 2 to 3 for CON.

Results There was no statistically significant difference in TNF-α levels among the three patient groups. IL-6 and IL-8 were significantly elevated in NEC group as compared with CON (p > 0.001), and in NEC group as compared with FI/suspect NEC. There was no significant difference in individual plasma levels of IL-6 or IL-8 between the CON and FI. The combined serum levels of IL-6 and IL-8 was more predictive of NEC stage II/III (area under the curve = 0.80; 95% confidence interval [CI]: 0.69–0.92; p < 0.0001).

Conclusion IL-6 and IL-8 were significantly elevated in infants with definitive surgical NEC but not those with FI. The combined level of IL-6 and IL-8 may be useful for distinguishing infants with suspect NEC/FI from those with NEC.

Changes in the incidence and surgical treatment of ankyloglossia in Canada

BACKGROUND

Recent reports show increases in rates of ankyloglossia and frenotomy in British Columbia. We carried out a study to determine temporal trends and regional variations in ankyloglossia and frenotomy in Canada.

METHODS

The study included all hospital-based live births in Canada (excluding Quebec) between April 2002 and March 2015, with information obtained from the Canadian Institute for Health Information. Information on ankyloglossia and frenotomy was obtained from records of hospital admission for childbirth. Temporal trends and provincial/territorial variations were quantified using rate ratios (RR) and 95% confidence intervals (CI).

RESULTS

Ankyloglossia rates increased from 6.86 in 2002 to 22.6 per 1000 live births in 2014 (P for trend < 0.001), while frenotomy rates increased from 3.76 in 2002 to 14.7 per 1000 live births in 2014 (P for trend < 0.001). Frenotomy rates among infants with ankyloglossia increased from 54.7% in 2002 to 63.9% in 2014 (RR: 1.18, 95% CI: 1.13-1.24). Compared with British Columbia, rates of ankyloglossia were over three-fold higher in Saskatchewan (RR: 3.40, 95% CI: 3.16-3.67), Alberta (RR: 3.50, 95% CI: 3.29-3.72) and the Yukon (RR: 3.62, 95% CI: 2.67-4.92), while rates of frenotomy were three- to four-fold higher in the Yukon (RR: 3.41, 95% CI: 2.28-5.10), Alberta (RR: 4.01, 95% CI: 3.71-4.33) and Saskatchewan (RR: 4.12, 95% CI: 3.76-4.52).

CONCLUSION

A desire to increase rates of breast feeding initiation and absence of standardized criteria for the diagnosis of ankyloglossia have resulted in runaway rates of frenotomy for newborn infants in some parts of Canada.

Three hundred babies born to underhoused mothers in Toronto-understanding the problem and how we can help

Little is known about pregnancy in underhoused women, possibly because the number of underhoused mothers with babies in Toronto has been significantly underestimated. Using a novel data collection method, it has been found that there are approximately 300 babies being born each year to underhoused women in Toronto. This finding has significant public health implications, as these women are at increased risk of multiple issues related to physical health, mental health, child protection, poverty and safety. This commentary presents a new data collection strategy, highlights the importance of accurate data collection and offers suggestions for supports for this over-looked population.

Clinical impact of improved point-of-care glucose monitoring in neonatal intensive care using Nova StatStrip: Evidence for improved accuracy, better sensitivity, and reduced test utilization

OBJECTIVES

Studies have demonstrated improved analytical performance of the Nova StatStrip glucose meter, but limited data is available on its clinical performance in critically ill neonates in the neonatal intensive care unit (NICU).

DESIGN AND METHODS

A retrospective charge review was conducted on 651 neonates admitted to the NICU over 2 years. Demographics, sample collection information, and clinical details were recorded. Glucose measurements were performed at the bedside using either the Nova StraStrip or LifeScan SureStep Flexx meters as well as corresponding measurements of laboratory venous plasma glucose. Performance was analyzed by receiver operator characteristic (ROC) curves for detecting hypoglycemia and critical glucose levels.

RESULTS

Linear regression analysis comparing StatStrip and laboratory venous plasma glucose samples demonstrated significantly tighter agreement (r(2)=0.7994) and accuracy (mean bias=0.13mmol/L) than SureStep (r(2)=0.6845 and mean bias=0.53mmol/L). StatStrip also showed improved sensitivity for detecting critical low glucose values ≤3.0mmol/L (80.9 vs 68.9%, p<0.05). ROC curve analysis further demonstrated excellent performance of StatStrip at this cutoff with an AUC of 0.98. Overall, neonates were also tested significantly less frequently with the StatStrip meter by 24% compared to SureStep.

CONCLUSIONS

Implementation of StatStrip led to better agreement with venous plasma glucose, improved detection of critical low glucose results, and more efficient test utilization. This study demonstrates the importance of accurate and sensitive glucose monitoring in the NICU.

Associations of Perinatal Clinical and Magnetic Resonance Imaging Measures with Developmental Outcomes in Children Born Very Preterm

OBJECTIVE

To identify perinatal risk factors associated with long-term neurocognitive and behavioral impairments in children born very preterm using a multivariate, partial least squares approach.

STUDY DESIGN

Twenty-seven perinatal clinical and magnetic resonance imaging measures were collected at birth and during the neonatal intensive care stay for 105 neonates born very preterm (≤ 32 weeks gestational age). One-half of the children returned for neuropsychological assessments at 2 and 4 years of age. Parent-reported behavioral measures were also obtained at 4 years of age. Three partial least squares analyses were performed to determine associations between clinical and radiologic measures with cognitive outcomes at 2 and 4 years of age, as well as with behavioral measures at 4 years of age.

RESULTS

Within the first components of each analysis, only intrauterine growth restriction, male sex, and absence of antenatal corticosteroid use were associated with poorer cognitive and language ability at 2 and 4 years of age, accounting for 79.6% and 71.4% of the total variance, respectively. In addition, white matter injury at term-equivalent age contributed to more problematic internalizing behaviors, behavioral symptoms, and impaired executive function at 4 years of age, accounting for 67.9% of the total variance.

CONCLUSIONS

Using this data-driven multivariate approach, specific measures in prenatal and early postnatal life are shown to be selectively and significantly associated with cognitive and behavioral outcomes in children born very preterm. Early detection of risk factors can help inform prognoses of children at greatest risk of long-term impairments.

Preventing the Progression of Intestinal Failure-Associated Liver Disease in Infants Using a Composite Lipid Emulsion: A Pilot Randomized Controlled Trial of SMOFlipid

BACKGROUND

To examine whether SMOFlipid prevents progression of intestinal failure-associated liver disease (IFALD) in parenteral nutrition (PN)-dependent infants with early IFALD (conjugated bilirubin 17-50 µmol/L, 1-3 mg/dL).

STUDY DESIGN

Pilot multicenter blinded randomized controlled trial comparing SMOFlipid with Intralipid. Patients received the trial lipid for up to 12 weeks, unless they achieved full enteral tolerance sooner. The primary clinical outcome was the serum conjugated bilirubin.

RESULTS

Twenty-four infants (mean age, 6 weeks) participated in the trial (13 Intralipid and 11 SMOFlipid). At the time of trial enrollment, patients in both groups were receiving 90% of their calories by PN. Mean duration on trial was 8 weeks and did not differ according to treatment ( P = .99). At trial conclusion, patients who received SMOFlipid had a lower conjugated bilirubin than those who received Intralipid (mean difference, -59 µmol/L; P = .03). Patients receiving SMOFlipid were also more likely to have a decrease in serum conjugated bilirubin to 0 µmol/L than those in the Intralipid group over the entire observation period (hazard ratio, 10.6; 95%; P = .03). The time to achievement of full enteral tolerance did not differ statistically (hazard ratio, 1.3; P = .59) between the groups. There was no significant difference in safety outcomes between the groups.

CONCLUSIONS

Compared with Intralipid, SMOFlipid reduces the risk of progressive IFALD in children with intestinal failure. This trial was registered at clinicaltrials.gov as NCT00793195.

Low birthweight, gestational age, need for surgical intervention and gram-negative bacteraemia predict intestinal failure following necrotising enterocolitis

AIM

Necrotising enterocolitis (NEC) is associated with high morbidity and mortality. The aim of this study was to identify predictors of intestinal failure (IF), morbidity and mortality following NEC.

METHODS

We performed a retrospective study of all neonates treated for NEC stage II or greater at a tertiary referral NICU between 2000 and 2009. Demographic data, need for surgery, residual bowel length and rates of bacteraemia, cholestasis, IF and mortality were analysed.

RESULTS

During the 10-year period, 301 patients were referred with NEC and 152 had surgical intervention. Overall mortality was 32%. Of the 230 infants who survived >42 days, 97 (42%) had IF at 42 days, decreasing to 15% at >90 days. The rate of IF was significantly higher in the surgical group than the medical group (OR 2.04, 95% CI, 1.25-3.35, p < 0.004), but 23% of the medically treated infants with NEC also developed IF. There was a significant relationship between IF and gram-negative bacteraemia, the need for surgery, cholestasis, liver failure and mortality.

CONCLUSION

Intestinal failure occurred in a significant proportion of infants with NEC. Predictors for IF among infants with NEC were low birthweight, low gestational age, need for surgical intervention and gram-negative bacteraemia.

A prospective comparison of intestinal sonography and abdominal radiographs in a neonatal intensive care unit

BACKGROUND

No study reported in the literature comprehensively compares findings on neonatal abdominal radiographs with sonography.

OBJECTIVE

To compare the findings on abdominal radiographs and sonograms in infants in intensive care, to better understand how the various intestinal gas patterns on radiographs relate to the spectrum of appearances on sonography and, second, to evaluate the ability of sonography to differentiate necrotizing enterocolitis from other intestinal pathology.

MATERIALS AND METHODS

We prospectively evaluated sonograms and radiographs, blinded to the other modality and to clinical information. Patients' charts were reviewed by a third blinded reader and used as a reference standard for diagnosis. We made associations between sonographic findings, radiographic intestinal gas patterns and clinical diagnoses.

RESULTS

We included 75 infants with gestational ages between 23 weeks and 41 weeks. Sonographic abnormalities were present in infants with all radiographic intestinal gas patterns, including normal patterns. We only saw absent intestinal perfusion and fluid collections on sonography (suggesting intestinal necrosis and sealed perforation) in infants with intestinal dilatation with elongation on radiographs. Separation of intestinal loops on radiographs was most commonly caused by reasons other than intestinal wall thickening. Increased intestinal echogenicity or free fluid with echoes on sonography correlated with a diagnosis of necrotizing enterocolitis, whereas anechoic free fluid correlated with absence of necrotizing enterocolitis.

CONCLUSION

Sonography is complementary to radiographs in infants with suspected intestinal pathology, with a spectrum of appearances seen on each modality. Some sonographic findings either strongly suggest necrotizing enterocolitis or supply evidence against this diagnosis.

Tissue engineered constructs for peripheral nerve surgery

BACKGROUND

Tissue engineering has been defined as "an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain, or improve tissue function or a whole organ". Traumatic peripheral nerve injury resulting in significant tissue loss at the zone of injury necessitates the need for a bridge or scaffold for regenerating axons from the proximal stump to reach the distal stump.

METHODS

A review of the literature was used to provide information on the components necessary for the development of a tissue engineered peripheral nerve substitute. Then, a comprehensive review of the literature is presented composed of the studies devoted to this goal.

RESULTS

Extensive research has been directed toward the development of a tissue engineered peripheral nerve substitute to act as a bridge for regenerating axons from the proximal nerve stump seeking the distal nerve. Ideally this nerve substitute would consist of a scaffold component that mimics the extracellular matrix of the peripheral nerve and a cellular component that serves to stimulate and support regenerating peripheral nerve axons.

CONCLUSIONS

The field of tissue engineering should consider its challenge to not only meet the autograft "gold standard" but also to understand what drives and inhibits nerve regeneration in order to surpass the results of an autograft.

Food fortification and decline in the prevalence of neural tube defects: does public intervention reduce the socioeconomic gap in prevalence?

OBJECTIVE

A significant decline in the prevalence of neural tube defects (NTD) through food fortification has been reported. Questions remain, however, about the effectiveness of this intervention in reducing the gap in prevalence across socioeconomic status (SES).

STUDY DESIGN

Using health number and through record linkage, children born in Ontario hospitals between 1994 and 2009 were followed for the diagnosis of congenital anomalies. SES quintiles were assigned to each child using census information at the time of birth. Adjusted rates and multivariate models were used to compare trends among children born in different SES groups.

RESULTS

Children born in low SES areas had significantly higher rates of NTDs (RR = 1.25, CI: 1.14-1.37). Prevalence of NTDs among children born in low and high SES areas declined since food fortification began in 1999 although has started rising again since 2006. While the crude decline was greater in low SES areas, after adjustment for maternal age, the slope of decline and SES gap in prevalence rates remained unchanged overtime.

CONCLUSIONS

While food fortification is successful in reducing the prevalence of NTDs, it was not associated with removing the gap between high and low SES groups.

Coupled ocean-atmosphere dynamics in the Indian Ocean during 1997-98

Climate variability in the Indian Ocean region seems to be, in some aspects, independent of forcing by external phenomena such as the El Niño/Southern Oscillation. But the extent to which, and how, internal coupled ocean-atmosphere dynamics determine the state of the Indian Ocean system have not been resolved. Here we present a detailed analysis of the strong seasonal anomalies in sea surface temperatures, sea surface heights, precipitation and winds that occurred in the Indian Ocean region in 1997-98, and compare the results with the record of Indian Ocean climate variability over the past 40 years. We conclude that the 1997-98 anomalies--in spite of the coincidence with the strong El Niño/Southern Oscillation event--may primarily be an expression of internal dynamics, rather than a direct response to external influences. We propose a mechanism of ocean-atmosphere interaction governing the 1997-98 event that may represent a characteristic internal mode of the Indian Ocean climate system. In the Pacific Ocean, the identification of such a mode has led to successful predictions of El Niño; if the proposed Indian Ocean internal mode proves to be robust, there may be a similar potential for predictability of climate in the Indian Ocean region.

Novel lipid-based approaches to pediatric intestinal failure-associated liver disease

Historically, intestinal failure-associated liver disease (IFALD) has been the greatest contributor to the morbidity experienced by children with intestinal failure. Although the cause of IFALD is multifactorial, recently much attention has been devoted to the critical role that intravenous lipid emulsions play in the development of IFALD. This attention has prompted an interest in alternate approaches to the provision of intravenous lipid in children with IFALD. The 2 approaches that have been advanced are that of lipid minimization and alternate intravenous lipid emulsions, including those containing ω-3 fatty acids. This article examines the rationale and current evidence for these approaches in children with intestinal failure. Our overall finding is that although these alternate approaches show significant promise, they have primarily been studied in uncontrolled settings, mainly in children with advanced IFALD. As such, we believe that there remains a lack of definitive evidence for their efficacy. Furthermore, important safety parameters remain to be evaluated, including the effect of these therapies on growth and development. Therefore, there is currently insufficient evidence to support the use of these novel therapies as standard of care in children with no or early IFALD with the goal of preventing the progression of liver disease.

Socioeconomic status and prevalence of congenital heart defects: does universal access to health care system eliminate the gap?

BACKGROUND

A twofold increase in the prevalence of congenital heart defects (CHDs) has been reported since the early 1970s with higher rates among children from low socioeconomic status (SES). This increase and the observed SES gap are postulated to be reflective of higher ascertainment, especially increased use of ultrasound and echography. The purpose of this study was to examine if trends over time in the prevalence of CHD were the same for high and low SES groups.

METHODS

Using the child's health number as a unique identifier and through record linkage, children born in Ontario between 1994 and 2007 were followed for the diagnosis of CHD. Using postal codes and census information, SES quintiles were assigned to each child. We used adjusted rates and used multivariate models to compare trends in the prevalence rate among children born in different SES groups.

RESULTS

Children born in low SES areas (23% of all births) had significantly higher rates of CHDs (rate ratio = 1.20; 95% confidence interval [CI] = 1.15-1.24). While prevalence of nonsevere CHDs declined in all SES groups since 2000, severe CHDs, especially atrial septal defects were on the rise during the study period.

DISCUSSION

It is assumed that increased ascertainment is responsible for observed increase in the prevalence of CHD, especially minor defects. While the trend and pattern over time changed for severe and nonsevere CHDs, the SES gap remained consistent during the study period. Our results indicate that even free and universal access to a health care system does not eliminate the SES gap observed in the prevalence of CHD.

The role of parenteral lipids in the development of advanced intestinal failure-associated liver disease in infants: a multiple-variable analysis

BACKGROUND

Given the recent interest in the role of ω-6 lipids in the development of intestinal failure-associated liver disease (IFALD), the authors sought to examine the role of parenteral lipids in the development of a serum conjugated bilirubin >100 µmol/L (5.9 mg/dL; CB100) in infants.

METHOD

Between 2003 and 2004, data were collected prospectively on infants undergoing an abdominal surgical procedure. Univariate logistic regression models for the prediction of CB100 by 1 year postoperatively were developed. Predictors significant at the 0.2 level on univariate analysis were entered into a backward stepwise multiple variable logistic regression.

RESULTS

Of 152 infants who received parenteral nutrition (PN) postoperatively, 22 developed CB100. Predictors that met criteria for consideration in the multiple-variable model were age, weight, small bowel length, presence of a stoma, proportion of enteral feeds postoperatively, septic episodes, days of maximal PN amino acid (>2.5 g/kg/d), days of maximal lipid (>2.5 g/kg/d), and PN duration. The final model included septic episodes (odds ratio, 3.23; 95% confidence interval, 1.8-5.9) and days of lipid >2.5 g/kg/d (1.04; 1.003-1.06). At 60 days of maximal lipid, the odds of advanced IFALD were increased 10-fold.

CONCLUSIONS

This model suggests a key role of parenteral lipids and septic events in the development of CB100 from IFALD. These data may provide targets, such as careful line care, reduction in maximal lipid dose, or alternate lipids such as ω-3 fatty acids, to prevent CB100, an identified marker of subsequent liver failure from IFALD.

Follow-up issues with multiples

The rate of multiple pregnancy has increased in developed countries, a finding usually attributed to more widespread use of assisted reproductive technologies. Multiple pregnancies are associated with a greater risk of pregnancy complications, including intrauterine growth restriction of one or more of the fetuses, vascular communications within a shared monochorionic placenta and premature delivery. Surviving infants are at significantly greater risk of developing cerebral palsy due to a combination of a higher proportion of them being preterm or of low birth weight, and complications associated with chorionicity. These infants are also at greater risk for abnormal cognitive development and learning disabilities for the same reasons. Parenting styles and family dynamics may also differ with multiples compared with singletons, which may affect long-term behaviour and development.Thus, infants of multiple pregnancies should receive careful neurodevelopmental follow-up. For larger, lower risk infants, this follow-up may be provided by general paediatricians within the community. However, for infants with birth weights of less than 1000 g or with a complicated antenatal or neonatal course, follow-up should be in a high-risk neonatal follow-up clinic with appropriate multidisciplinary support.

Childhood outcomes of neonates diagnosed with portal vein thrombosis

AIM

The study aims to determine childhood outcomes of neonates diagnosed with portal vein thrombosis (PVT).

METHODS

A retrospective chart review of neonates diagnosed with PVT who had documented follow up (physical examination, laboratory tests or ultrasonographic examination) at the age of 2 years or beyond was conducted.

RESULTS

Data were available for 70 children (71% of eligible neonates) at a median age of 5 years (range 2-8 years). Physical examination was unremarkable in all who were examined (n= 68). Twenty-five children had liver functions assessed and only mild abnormalities were detected in nine children. Six of 25 patients tested for thrombophilia showed abnormalities. Thirty-seven children had ultrasonographic follow up. Left lobar atrophy (LLA) was noted in 20 children (16 had isolated LLA, two had LLA and splenomegaly, and two had LLA and portal hypertension). Five children who had normal ultrasound examinations at discharge had splenomegaly (two with additional finding of LLA) at follow up. Two children with portal hypertension diagnosed during neonatal period needed porta-caval shunting.

CONCLUSION

Our results show that among patients, who had PVT as neonates, 28% still had asymptomatic LLA in childhood, 7% had slowly progressive splenomegaly and 3% required shunting because of progression of portal hypertension. Ultrasonographic follow up was the most sensitive method in detecting progression associated with neonatal PVT. Until more data are available, periodic long-term ultrasonographic follow up should be considered for neonates diagnosed with PVT.

Placental pathology in neonatal stroke

OBJECTIVE

Neonatal stroke is increasingly recognized, and risk factors have been identified. The placenta has been implicated as a potential contributor to neonatal stroke; however, pathology has not been previously described. This case series systematically evaluates prenatal, maternal, and neonatal risk factors and describes placental pathology in 12 cases of neonatal stroke.

PATIENTS AND METHODS

We reviewed the Canadian Pediatric Ischemic Stroke Registry from 1992 to 2006, which consists of 186 neonatal stroke patients. Twelve patients with symptomatic cerebral arterial ischemic stroke or sinovenous thrombosis had their placenta available for pathologic examination. Clinical presentation; maternal, prenatal, and neonatal risk factors for stroke; and patient outcome were collected retrospectively from patient charts. Gross and microscopic placental pathology was described and classified into 4 pathologic categories.

RESULTS

Of 12 patients studied, 10 patients were male, 5 patients had arterial ischemic stroke, and 7 patients had sinovenous thrombosis. Maternal risk factors were identified in 5 cases, prenatal risk factors in 10 cases, and neonatal risk factors in 10 cases. Placental lesions were present in 10 cases and were classified as thromboinflammatory process in 6 cases, sudden catastrophic event in 5 cases, decreased placental reserve in 3 cases, and stressful intrauterine environment in 2 cases.

CONCLUSIONS

This study reviews detailed placental pathology in a selected cohort of patients presenting near the time of delivery and correlates this with clinical presentation, outcome, and risk factors for neonatal stroke. Our results suggest that multiple risk factors are involved in neonatal stroke, and placental pathology may be a contributing factor. The implications of specific placental lesions remain to be determined with larger, case-controlled studies.

Lysine requirement in parenterally fed postsurgical human neonates

BACKGROUND

The lysine requirement of human neonates receiving parenteral nutrition (PN) has not been determined experimentally.

OBJECTIVE

The objective was to determine the parenteral lysine requirement for human neonates by using the minimally invasive indicator amino acid oxidation technique with l-[1-(13)C] phenylalanine as the indicator amino acid.

DESIGN

Eleven postsurgical neonates were randomly assigned to 15 lysine intakes ranging from 50 to 260 mg . kg(-1) . d(-1). Breath and urine samples were collected at baseline and at plateau for (13)CO(2) (F(13)CO(2)) and amino acid enrichment, respectively. The mean lysine requirement was determined by applying a 2-phase linear regression crossover analysis to the measured rates of F(13)CO(2) release and l-[1-(13)C]phenylalanine oxidation.

RESULTS

The mean parenteral lysine requirement determined by F(13)CO(2) release oxidation was 104.9 mg . kg(-1) . d(-1) (upper and lower CIs: 120.6 and 89.1 mg . kg(-1) . d(-1), respectively). The mean lysine parenteral requirement determined by phenylalanine oxidation was 117.6 mg . kg(-1) . d(-1) (upper and lower CIs: 157.5 and 77.6 mg . kg(-1) . d(-1), respectively). Graded intakes of lysine had no effect on phenylalanine flux.

CONCLUSION

We recommend a mean lysine requirement for the postsurgical PN-fed neonate of 104.9 mg . kg(-1) . d(-1), which is 32-43% of the lysine concentration presently found in commercial PN solutions (246-330 mg . kg(-1) . d(-1)). This trial was registered at clinicaltrials.gov as NCT00779753.

Cytokine levels in neonatal necrotizing enterocolitis and long-term growth and neurodevelopment

OBJECTIVE

To investigate if circulating cytokines are related to growth and neurodevelopmental outcome following necrotizing enterocolitis (NEC).

STUDY DESIGN

Pro-inflammatory cytokine levels were measured prospectively in 40 neonates and compared with neurodevelopmental outcome. Cytokine levels were measured at the onset of feeding intolerance (Group II, n = 17) or NEC (Group III, n = 10) and at weeks 2-3 in control infants (Group I, n = 13). Neurodevelopmental outcome was assessed at the age of 24-28 months. Data were analysed using descriptive statistics, non-parametric tests and Student t-test.

RESULTS

Median birth weights (range) in groups I, II and III were 1120 (525-1564) g, 1068 (650-1937) g and 1145 (670-2833) g, and median gestational ages (range) were 28 (24-35) weeks 28 (24-35) weeks and 28 (25-37) weeks respectively. NEC occurred in 10 infants. Serum IL-6 (interleukin-6) was elevated in group III, (p = 0.03). Significant developmental delay was found in 12% of the infants in Group II and 20% of the infants in Group III, but no infant in group I. Five infants in group III with NEC (50%), had head ultrasound abnormalities. At 1 year of age, growth, weight and head circumference were significantly different in Group III, however, at two years of age, only height was significantly different, p < 0.02. Although there was wide variation, neonatal cytokine levels tended to be greater in the infants later found to have abnormal cognitive and psychomotor outcomes.

CONCLUSION

This study suggests that increased serum levels of pro-inflammatory cytokines may play a role in the poor growth and neurodevelopment associated with this high-risk population.

The addition of cysteine to the total sulphur amino acid requirement as methionine does not increase erythrocytes glutathione synthesis in the parenterally fed human neonate

Controversy exists as to whether the parenterally (PN) fed human neonate is capable of synthesizing adequate cysteine from methionine if the total dietary requirement for sulfur amino acid (SAA) is provided as methionine only. The goal of this study was to gather data on whether glutathione (GSH) synthesis is maximized at a methionine intake previously shown to be adequate for protein synthesis in the PN-fed human neonate. We measured GSH concentration, fractional, and absolute synthesis rate in five PN-fed human neonates. Each neonate underwent two isotope infusion studies of 7 h duration after a 2-d adaptation to the total SAA requirement (methionine only) and again after a further 2-d adaptation to the same methionine intake supplemented with cysteine at 10 mg x kg(-1) x d(-1). Cysteine supplementation did not significantly affect GSH synthesis. These data suggest that term infants are capable of synthesizing cysteine from methionine, not only for protein but also for GSH synthesis.

Ultrastructure of Lamellar Bodies in Congenital Surfactant Deficiency

Congenital surfactant deficiency (CSD) is a newly identified neonatal lung disorder associated with a variety of molecular defects affecting surfactant synthesis and secretion in alveolar type II cells. The authors present ultrastructural findings of abnormal lamellar bodies in lung biopsies from 4 infants with CSD. All were term infants presenting shortly after birth with severe respiratory failure that was unresponsive to conventional therapy and all died within the first month of life. Lung biopsies were performed between 8 and 25 days of age. Biochemical and molecular studies in 2 unrelated male infants identified SP-B deficiency, one case with 121 ins 2 mutation and the second with a 209 + 4 A > G mutation. Light microscopy in both cases showed features of alveolar proteinosis. Ultrastructurally, alveolar type II cells lacked mature lamellar bodies, and their cytoplasm contained numerous pleomorphic inclusions with membranous and vesicular structures not seen in normal type II cells. The other 2 infants were a pair of siblings in whom molecular studies identified mutations in ABCA3 transporter gene. Light microscopy showed features of acinar dysplasia and desquamative interstitial pneumonitis. TEM studies revealed absence of mature lamellar bodies in type II cells and instead showed a mixture of cytoplasmic electron-dense inclusions with concentric membranes and distinctive electron dense aggregates. The ultrastructural changes in alveolar type II cells correlated well with specific gene defect. In SP-B deficiency, the absence of mature lamellar bodies is consistent with the postulated role for this protein in the formation of lamellar bodies. The lack of mature lamellar bodies in the ABCA3 gene mutations is due to the dysfunction of this endogenous lipid transporter that targets surfactant lipid moieties to the lamellar bodies. The findings demonstrate the importance of TEM studies of lung biopsies from infants with CSD as it is a critical adjunct in the diagnosis of neonatal lung disease and in defining the underlying cellular defects.

Threonine requirement of parenterally fed postsurgical human neonates

BACKGROUND

The threonine requirement of human neonates who receive parenteral nutrition (PN) has not been determined experimentally.

OBJECTIVE

The objective was to determine the parenteral threonine requirement for human neonates by using the minimally invasive indicator amino acid oxidation technique with L-[1-(13)C]phenylalanine as the indicator amino acid.

DESIGN

Nine postsurgical neonates were randomly assigned to 16 threonine intakes ranging from 10 to 100 mg . kg(-1) . d(-1). Breath and urine samples were collected at baseline and at plateau for (13)CO(2) and amino acid enrichment, respectively. The mean threonine requirement was determined by applying a 2-phase linear regression crossover analysis to the measured rates of (13)CO(2) release (F(13)CO(2)) and L-[1-(13)C]phenylalanine oxidation.

RESULTS

The mean threonine parenteral requirement determined by using phenylalanine oxidation was 37.6 mg . kg(-1) . d(-1) (upper and lower confidence limits, respectively: 29.9 and 45.2 mg . kg(-1) . d(-1)) and by using F(13)CO(2) oxidation was 32.8 mg . kg(-1) . d(-1) (upper and lower confidence limits, respectively: 29.7 and 35.9 mg . kg(-1) . d(-1)). Graded intakes of threonine had no effect on phenylalanine flux.

CONCLUSION

This is the first study to report on the threonine requirement for human neonates receiving PN. We found that the threonine requirement for postsurgical PN-fed neonates is 22-32% of the content of threonine that is presently found in commercial PN solutions (111-165 mg . kg(-1) . d(-1)).

Occipital lobe injury and cortical visual outcomes after neonatal hypoglycemia

OBJECTIVES

Hypoglycemia is a significant problem in neonates, and a pattern of parietooccipital diffusion restriction on MRI scans has been reported. The purpose of this study was to determine whether hypoglycemic injury, as indicated by diffusion restriction in the occipital lobes, correlated with visual evoked potentials and long-term cortical visual dysfunction.

METHODS

A cohort of 45 neonates from 2000-2005 with diffusion-weighted MRI studies after hypoglycemia was studied retrospectively. Perinatal history and follow-up data were analyzed, and results were correlated with diffusion-weighted imaging findings.The presence of occipital diffusion restriction was assessed qualitatively, and the mean apparent diffusion coefficients of mesial occipital lobes were calculated.

RESULTS

Among 25 patients who underwent diffusion-weighted imaging within 6 days after the onset of hypoglycemia, restricted diffusion in the occipital lobes was found in 8 (50%) of 16 term infants but not in preterm infants. For the remaining 20 patients, who had diffusion-weighted imaging performed >6 days after the initial onset of hypoglycemia, occipital diffusion restriction was not seen, even if hypoglycemia was ongoing. Restricted diffusion was associated with abnormal visual evoked potentials detected within 1 week after birth. Cortical visual deficits were seen in a significant proportion of patients with recurrent hypoglycemia and were correlated significantly with low mesial occipital apparent diffusion coefficient values.

CONCLUSIONS

Diffusion-weighted imaging studies performed within 6 days after initial hypoglycemia were sensitive in term but not preterm neonates. Diffusion restriction, with low apparent diffusion coefficient values, in the mesial occipital poles may indicate the prognosis for visual outcomes in acute settings after neonatal hypoglycemia.

Total sulfur amino acid requirement and metabolism in parenterally fed postsurgical human neonates

BACKGROUND

Except for tyrosine, the amino acid requirements of human neonates receiving parenteral nutrition (PN) have not been experimentally derived.

OBJECTIVES

The objectives were to determine the total sulfur amino acid (TSAA) requirement (methionine in the absence of cysteine) of postsurgical, PN-fed human neonates by using the indicator amino acid oxidation (IAAO) technique with L-[1-(13)C]phenylalanine as the indicator.

DESIGN

Fifteen postsurgical neonates were randomly assigned to receive 1 of 18 methionine intakes ranging from 10 to 120 mg x kg(-1) x d(-1), delivered in a customized, cysteine-free amino acid solution. Breath and urine samples were collected for the measurement of (13)CO(2) and amino acid enrichment. Blood samples were collected at baseline and after the test methionine infusion for the measurement of plasma methionine, homocysteine, cystathionine, and cysteine concentrations.

RESULTS

Breakpoint analysis determined the mean TSAA requirements to be 47.4 (95% CI: 38.7, 56.1) and 49.0 (95% CI: 39.9, 58.0) mg x kg(-1) x d(-1) with the use of oxidation and F(13)CO(2), respectively.

CONCLUSIONS

This is the first study to report the TSAA requirement of postsurgical, PN-fed human neonates. The estimated methionine requirement expressed as a proportion of the methionine content of current commercial pediatric PN solutions was 90% (range: 48-90%) of that found in the lowest methionine-containing PN solution.