High Rates of Positive Severe Combined Immunodeficiency Screening Among Newborns with Severe Intestinal Failure

PURPOSE

Severe combined immunodeficiency (SCID) screening by T-cell receptor excision circles (TREC) has been part of Massachusetts routine newborn screening since 2009. Tetratricopeptide repeat domain 7A gene (TTC7A) mutations responsible for hereditary multiple intestinal atresia with combined immunodeficiency (MIA-CID) were also recently identified. We reviewed newborn SCID screening among infants with intestinal failure and correlated results with patient characteristics and outcomes.

METHODS

Records of infants with severe intestinal failure and available newborn screen results treated at a single center 2009-2016 were reviewed retrospectively. Patients with 1 or more positive SCID screens (<252 TREC copies/μL) were compared with those without positive screens. TREC copies/μL were compared with population norms.

RESULTS

Of 70 included infants, 34% had newborn screens with TREC <252 copies/μL, compared with 0.3% of the general population; TREC levels for the cohort were lower than the general population (p<0.001). Of those with positive screens, 42% had prior or subsequent negative screening, 8% had no further workup, and 50% had flow cytometry showing: severe T-cell lymphopenia (absolute CD3+ <1500 cells/mcL) in 8, 3 of whom had TTC7A mutation-associated MIA-CID. Four had CD3+ >1500 cells/mcL. MIA-CID patients had the lowest serum citrulline in the cohort; 4 of the 8 patients with CD3+ <1500 cells/mcL on flow cytometry had newborn screening notable for severe hypocitrullinemia (<3 μM).

CONCLUSION

Infants with intestinal failure have lower TREC copies/μL than the general population; one-third had levels concerning for SCID, and 11% were diagnosed with severe T-cell lymphopenia. The clinical implications and etiology of this phenomenon remain unknown, but may be related to hypocitrullinemia.

Radiographic measurement of intestinal length among children with short bowel syndrome: Retrospective determination remains problematic

PURPOSE

Small bowel length is the most reliable predictor of enteral independence in pediatric short bowel syndrome. Retrospectively measured bowel lengths on upper GI with small bowel follow-through (UGI/SBFT) were compared to operative measurements.

METHODS

A pediatric radiologist and surgical trainees blinded to operative measurements retrospectively analyzed UGI/SBFT studies using the digital radiography curved measurement tool. Children with SBS and severe intestinal failure (parenteral nutrition >90days) at a multidisciplinary intestinal failure program 2002-2015 were included. Data were expressed as median (Q1, Q3).

RESULTS

Thirty-six children aged 0.8 (0.4, 3.7) years were analyzed. Fifty-six percent had intestinal malrotation, and 58% had prior serial transverse enteroplasty. Studies were conducted within 10 (7, 20) days of surgery. Intraoperative bowel length was 90cm (45, 142), while UGI/SBFT measurement by radiologist was 45cm (28, 63), with a mean difference of 47cm (SD 58cm, p<0.001) and a mean percent error of 50%. Radiographic assessment underestimated intestinal length in 83% of patients.

CONCLUSION

Bowel length measured retrospectively from upper GI with small bowel follow-through studies usually underestimated intraoperative bowel length. The limits of agreement were too wide for this technique to be clinically useful. Operative measurement remains necessary to assess intestinal length and rehabilitation potential.

TYPE OF STUDY

Study of Diagnostic Test.

LEVEL OF EVIDENCE

Level III.

Severe neurodevelopmental disability and healthcare needs among survivors of medical and surgical necrotizing enterocolitis: A prospective cohort study

PURPOSE

This study characterizes neurodevelopmental outcomes and healthcare needs of extremely low birth weight (ELBW) survivors of necrotizing enterocolitis (NEC) compared to ELBW infants without NEC.

METHODS

Data were collected prospectively on neonates born 22-27weeks' gestation or 401-1000g at 47 Vermont Oxford Network member centers from 1999 to 2012. Detailed neurodevelopmental evaluations were conducted at 18-24months corrected age. Information regarding rehospitalizations, postdischarge surgeries, and feeding was also collected. "Severe neurodevelopmental disability" was defined as: bilateral blindness, hearing impairment requiring amplification, inability to walk 10 steps with support, cerebral palsy, and/or Bayley Mental or Psychomotor Developmental Index <70. Diagnosis of NEC required both clinical and radiographic findings.

RESULTS

There were 9063 children without NEC, 417 with medical NEC, and 449 with surgical NEC evaluated. Significantly higher rates of morbidity were observed among infants with a history of NEC. Those with surgical NEC were more frequently affected across all outcome measures at 18-24months corrected age: 38% demonstrated severe neurodevelopmental disability, nearly half underwent postdischarge operations, and a quarter required tube feeding at home.

CONCLUSION

At 18-24months, extremely low birth weight survivors of necrotizing enterocolitis were at markedly increased risk (p<0.001) for severe neurodevelopmental disability, postdischarge surgery, and tube feeding.

LEVEL OF EVIDENCE

II (prospective cohort study with <80% follow-up rate).

Morbidity and mortality among "big" babies who develop necrotizing enterocolitis: A prospective multicenter cohort analysis

BACKGROUND

Necrotizing enterocolitis (NEC) is classically a disease of prematurity, with less reported regarding morbidity and mortality of this disease among other infants.

METHODS

Data were prospectively collected from 2009 to 2015 at 252 Vermont Oxford Network member centers on neonates with birth weight>2500g admitted to a participating NICU within 28days of birth.

RESULTS

Of 1629 neonates with NEC, gestational age was 37 (36, 39) weeks, and 45% had major congenital anomalies, most commonly gastrointestinal defects (20%), congenital heart defects (18%), and chromosomal anomalies (7%). For the 23% of infants who had surgery for NEC, mortality and length of stay were 23% and 63 (36, 94) days versus 8% and 34 (22, 61) days in medical NEC. Independent predictors of mortality were congenital heart defects (p<0.0001), chromosomal abnormalities (p<0.05), other congenital malformations (p<0.001), surgical NEC (p<0.0001), and sepsis (p<0.05). All of these in addition to gastrointestinal defects were independent predictors of increased length of stay. Nutritional morbidity at discharge included 6% receiving no enteral feeds and 27% who were <10th percentile weight-for-age.

CONCLUSIONS

Major congenital anomalies are present in nearly half of >2500g birth weight infants diagnosed with necrotizing enterocolitis. Morbidity and mortality increase with sepsis, surgical disease, and congenital anomalies.

TYPE OF STUDY

Prognosis Study.

LEVEL OF EVIDENCE

Level II.

Long-term outcomes of pediatric intestinal failure

Management of pediatric intestinal failure has evolved in recent decades, with improved survival since the advent of specialized multidisciplinary intestinal failure centers. Though sepsis and intestinal failure associated liver disease still contribute to mortality, we now have growing data on the long-term outcomes for this population. While intestinal adaptation and parenteral nutrition weaning is most rapid during the first year on parenteral support, achievement of enteral autonomy is possible even after many years as energy and protein requirements decline dramatically with age. Intestinal transplant is an option for patients experiencing complications of long-term parenteral nutrition who are expected to have permanent intestinal failure, but outcomes are hindered by immunosuppression-related complications. Much of the available data comes from single center retrospective reports, with variable inclusion criteria, intestinal failure definitions, and follow-up durations; this limits the ability to analyze outcomes and identify best practices. As most children now survive long-term, the focus of management has shifted to the avoidance and management of comorbidities, support of normal growth and development, and optimization of quality of life for these medically and surgically complex patients.

Contemporary Outcomes of Infants with Gastroschisis in North America: A Multicenter Cohort Study

OBJECTIVE

To quantify outcomes and analyze factors predictive of morbidity and mortality in infants with gastroschisis.

STUDY DESIGN

Clinical data regarding neonates with gastroschisis born between 2009 and 2014 were prospectively collected at 175 North American centers. Multivariate regression was used to assess risk factors for mortality and length of stay (LOS).

RESULTS

Gastroschisis was diagnosed in 4420 neonates with median birth weight 2410 g (IQR 2105-2747). Survival (discharge home or alive in hospital at 1 year) was 97.8% with a 37 day median LOS (IQR 27-59). Sepsis, defined by positive blood or cerebrospinal fluid culture, was the only significant independent predictor of mortality (P = .04). Significant independent determinants of LOS and the percentage of neonates affected were as follows: bowel resection (9.8%, P < .0001), sepsis (8.6%, P < .0001), presence of other congenital anomalies (7.6%, including 5.8% with intestinal atresias, P < .0001), necrotizing enterocolitis (4.5%, P < .0001), and small for gestational age (37.3%, P = .0006). Abdominal surgery in addition to gastroschisis repair occurred in 22.3%, with 6.4% receiving gastrostomy or jejunostomy tubes and 6.3% requiring ostomy creation. At discharge, 57.0% were less than the 10th percentile weight for age. The mode of delivery (52.4% cesarean delivery) was not associated with any differences in outcome.

CONCLUSIONS

Although neonates with gastroschisis have excellent overall survival they remain at risk for death from sepsis, prolonged hospitalization, multiple abdominal operations, and malnutrition at discharge. Outcomes appear unaffected by the use of cesarean delivery. Further opportunities for quality improvement include sepsis prevention and enhanced nutritional support.

High prevalence of same-sex twins in patients with cloacal exstrophy: Support for embryological association with monozygotic twinning

PURPOSE

Previous studies have hypothesized that cloacal exstrophy may be caused by errors early in embryological development related to monozygotic twinning. This study reports the prevalence of twins in a large cohort of patients with cloacal exstrophy.

METHODS

Patients with cloacal exstrophy treated 1974-2015 were reviewed for reports of multiple gestation or conjoined twinning. The genetic sex of the patient and their twin, and any mention of anomaly in the twin were recorded. Neither placental exam nor genetic testing results were available to definitively determine zygosity.

RESULTS

Of 71 patients, 10 had a live born twin (14%), all of whom were of the same genetic sex as the affected patient. One additional patient's twin suffered intrauterine fetal demise, and another patient had a conjoined heteropagus twin. None of the twins were affected by exstrophy-epispadias complex. The rate of twin birth in this cohort was 4.4-7.7 higher than that reported by the Centers for Disease Control in the general population time period (P<0.001), with a striking preponderance of same-sex pairs.

CONCLUSIONS

The highly significant prevalence of same-sex twin pairs within this cohort supports the hypothesis that the embryogenesis of cloacal exstrophy may be related to errors in monozygotic twinning.

LEVEL OF EVIDENCE

2b.

New Medical and Surgical Insights Into Neonatal Necrotizing Enterocolitis: A Review

IMPORTANCE

Necrotizing enterocolitis (NEC) has long remained a significant cause of morbidity and mortality in neonatal intensive care units. While the mainstay of treatment for this devastating condition remains largely supportive, research efforts continue to be directed toward understanding pathophysiology as well as how best to approach surgical management when indicated.

OBSERVATIONS

In this review, we first examine recent medical observations, including overviews on the microbiome and a brief review of the use of probiotics. Next, we discuss the use of biomarkers and how clinicians may be able to use them in the future to predict the course of disease and, perhaps, the need for surgical intervention. We then provide an overview on the use of exclusive human milk feeding and the utility of this approach in preventing NEC. Finally, we discuss recent developments in the surgical management of NEC, beginning with indications for surgery and following with a section on technical surgical considerations, including peritoneal drain vs laparotomy. The review concludes with outcomes from infants with surgically treated NEC.

CONCLUSIONS AND RELEVANCE

Although medical treatment options for NEC are largely unchanged, understanding of the disease continues to evolve. As new research methods are developed, NEC pathophysiology can be more completely understood. In time, it is hoped that data from ongoing and planned clinical trials will allow us to routinely add targeted preventive measures in addition to human milk, such as prebiotics and probiotics, to the management of high-risk infants. In addition, the discovery of novel biomarkers may not only prove useful in predicting severity of illness but also will hopefully allow for identification of the disease prior to onset of clinical signs. Finally, continued investigation into optimizing surgical outcomes is essential in this population of infants, many of whom require long-term parenteral therapy and intestinal rehabilitation.

Nutrient delivery in mechanically ventilated surgical patients in the pediatric critical care unit

PURPOSE

Inadequate nutrient intake is associated with poor outcomes in critically ill children. We examined macronutrient delivery in surgical patients in the pediatric intensive care unit (PICU).

METHODS

In a prospective international cohort study of mechanically ventilated children (1month to 18years), we recorded adequacy of cumulative nutrient delivery in the PICU. Surgical patients enrolled in this study were included in the current analysis. Protein intake <60% of the prescribed goal was deemed inadequate.

RESULTS

Five hundred nineteen surgical patients, 45% female, median age 2years (IQR 0.5, 8), BMI z score -0.26, with 9-day median PICU stay and 60-day mortality 5.8% were enrolled. Three hundred forty-one (66%) patients received enteral nutrition (EN), and median time of initiation was PICU day 2. EN delivery was interrupted in 68% of these patients for a median duration of 9hours. Median enteral protein delivery was <15% of the prescribed goal and was <60% in two-thirds of the cohort. Patients with inadequate enteral protein delivery had longer time to EN initiation (p<0.001) and longer duration of EN interruptions (p<0.001) compared to those with adequate delivery.

CONCLUSION

Enteral protein delivery in critically ill pediatric surgical patients is inadequate. Early EN initiation and minimizing interruptions may increase protein delivery and potentially improve outcomes in this population.

LEVEL OF EVIDENCE

I.

TYPE OF STUDY

Prospective study.

Growth morbidity in patients with cloacal exstrophy: a 42-year experience

PURPOSE

Cloacal exstrophy is associated with multiple comorbidities that affect growth. This report describes long-term growth outcomes in a large cohort of patients with cloacal exstrophy and explores associated comorbidities.

METHODS

Records of 71 patients with cloacal exstrophy who were treated between 1974 and 2015 were reviewed, and 62 patients with growth data from 2 to 20years of age were included. Genetic sex, gender of rearing, and all heights, weights, and comorbidities were noted for each patient. Height-for-age, weight-for-age, and body mass index z-scores (HAZ, WAZ, and BMIZ) were determined using US Centers for Disease Control 2000 growth data, and average patient z-scores were calculated.

RESULTS

There were 904 height and 1301 weight measurements available for 62 patients. 31 were genetically 46,XY, 21 of whom underwent gonadectomy in infancy and were raised female. 46,XX patients, 46,XY male patients, and 46,XY female patients all had median HAZ and WAZ substantially lower than the general population, with median HAZ less than -2, while maintaining normal BMIZ. Short bowel syndrome and enterocystoplasty with intestine were associated with lower z-scores for all parameters.

CONCLUSIONS

Patients with cloacal exstrophy have significant multifactorial long-term growth failure. These benchmark data can be used to further optimize management.

LEVEL OF EVIDENCE

2b.

Enteral autonomy, cirrhosis, and long term transplant-free survival in pediatric intestinal failure patients

PURPOSE

Patient selection for transplant evaluation in pediatric intestinal failure is predicated on the ability to assess long-term transplant-free survival. In light of trends toward improved survival of intestinal failure patients in recent decades, we sought to determine if the presence of biopsy-proven hepatic cirrhosis or the eventual achievement of enteral autonomy were associated with transplant-free survival.

METHODS

After IRB approval, records of all pediatric intestinal failure patients (parenteral nutrition (PN) >90 days) treated at a single intestinal failure center from February 2002 to September 2014 were reviewed. Chi-squared, Mann-Whitney, and log-rank testing were performed as appropriate.

RESULTS

Of 313 patients, 174 eventually weaned off PN. Liver biopsies were available in 126 patients (most common indication was intestinal failure associated liver disease, IFALD), and 23 met histologic criteria for cirrhosis. Transplant-free survival for the whole cohort of 313 patients was 94.7% at 1 year and 89.2% at 5 years. Among patients with liver biopsies, transplant-free survival in cirrhotics vs. noncirrhotics was 95.5% vs. 94.1% at one year and 95.5% vs. 86.7% at 5 years (P=0.29). Transplant-free survival in patients who achieved enteral autonomy compared with patients who remained PN dependent was 98.2% vs. 90.3% at one year and 98.2% vs. 76.9% at 5 years (P<0.001). There was no association between cirrhosis and eventual enteral autonomy (P=0.88).

CONCLUSIONS

Achieving enteral autonomy was associated with improved transplant-free survival in pediatric intestinal failure patients. There was no association between histopathological diagnosis of cirrhosis and transplant-free survival in the cohort. These data suggest that automatic transplant referral may not be required for histopathological diagnosis of cirrhosis alone, and that ongoing efforts aimed at achievement of enteral autonomy remain paramount in pediatric intestinal failure.

Necrotizing enterocolitis is associated with earlier achievement of enteral autonomy in children with short bowel syndrome

PURPOSE

Necrotizing enterocolitis (NEC) remains one of the most common underlying diagnoses of short bowel syndrome (SBS) in children. The relationship between the etiology of SBS and ultimate enteral autonomy has not been well studied. This investigation sought to evaluate the rate of achievement of enteral autonomy in SBS patients with and without NEC.

METHODS

Following IRB approval, 109 patients (2002-2014) at a multidisciplinary intestinal rehabilitation program were reviewed. The primary outcome evaluated was achievement of enteral autonomy (i.e. fully weaning from parenteral nutrition). Patient demographics, primary diagnosis, residual small bowel length, percent expected small bowel length, median serum citrulline level, number of abdominal operations, status of the ileocecal valve (ICV), presence of ileostomy, liver function tests, and treatment for bacterial overgrowth were recorded for each patient.

RESULTS

Median age at PN onset was 0 weeks [IQR 0-0]. Median residual small bowel length was 33.5 cm [IQR 20-70]. NEC was present in 37 of 109 (33.9%) of patients. 45 patients (41%) achieved enteral autonomy after a median PN duration of 15.3 [IQR 7.2-38.4]months. Overall, 64.9% of patients with NEC achieved enteral autonomy compared to 29.2% of patients with a different primary diagnosis (p=0.001, Fig. 1). Patients with NEC remained more likely than those without NEC to achieve enteral autonomy after two (45.5% vs. 12.0%) and four (35.7% vs. 6.3%) years on PN (Fig. 1). Logistic regression analysis demonstrated the following parameters as independent predictors of enteral autonomy: diagnosis of NEC (p<0.002), median serum citrulline level (p<0.02), absence of a jejunostomy or ileostomy (p=0.013), and percent expected small bowel length (p=0.005).

CONCLUSIONS

Children with SBS because of NEC have a significantly higher likelihood of fully weaning from parenteral nutrition compared to children with other causes of SBS. Additionally, patients with NEC may attain enteral autonomy even after long durations of parenteral support.

Predictors of Enteral Autonomy in Children with Intestinal Failure: A Multicenter Cohort Study

OBJECTIVES

In a large cohort of children with intestinal failure (IF), we sought to determine the cumulative incidence of achieving enteral autonomy and identify patient and institutional characteristics associated with enteral autonomy.

STUDY DESIGN

A multicenter, retrospective cohort analysis from the Pediatric Intestinal Failure Consortium was performed. IF was defined as severe congenital or acquired gastrointestinal diseases during infancy with dependence on parenteral nutrition (PN) >60 days. Enteral autonomy was defined as PN discontinuation >3 months.

RESULTS

A total of 272 infants were followed for a median (IQR) of 33.5 (16.2-51.5) months. Enteral autonomy was achieved in 118 (43%); 36 (13%) remained PN dependent and 118 (43%) patients died or underwent transplantation. Multivariable analysis identified necrotizing enterocolitis (NEC; OR 2.42, 95% CI 1.33-4.47), care at an IF site without an associated intestinal transplantation program (OR 2.73, 95% CI 1.56-4.78), and an intact ileocecal valve (OR 2.80, 95% CI 1.63-4.83) as independent risk factors for enteral autonomy. A second model (n = 144) that included only patients with intraoperatively measured residual small bowel length found NEC (OR 3.44, 95% CI 1.36-8.71), care at a nonintestinal transplantation center (OR 6.56, 95% CI 2.53-16.98), and residual small bowel length (OR 1.04 cm, 95% CI 1.02-1.06 cm) to be independently associated with enteral autonomy.

CONCLUSIONS

A substantial proportion of infants with IF can achieve enteral autonomy. Underlying NEC, preserved ileocecal valve, and longer bowel length are associated with achieving enteral autonomy. It is likely that variations in institutional practices and referral patterns also affect outcomes in children with IF.

Necrotizing Enterocolitis and Central Line Associated Blood Stream Infection Are Predictors of Growth Outcomes in Infants with Short Bowel Syndrome

OBJECTIVES

To describe the natural history of growth patterns and nutritional support in a cohort of infants with short bowel syndrome (SBS), and to characterize risk factors for suboptimal growth.

STUDY DESIGN

A retrospective chart review of 51 infants with SBS followed by our intestinal rehabilitation program. Weight and length data were converted to age, sex, and gestational age-standardized weight-for-age z-scores (WAZ) and length-for-age z-scores (LAZ).

RESULTS

Median (IQR) age at enrollment was 8.3 (0.9-14.6) weeks, and follow-up duration was 10 (8-13) months, including both inpatient and outpatient visits. Both WAZ and LAZ followed a U-shaped curve, with median for newborns (WAZ = -0.28; LAZ = -0.41), a nadir at age 6 months (-2.38 and -2.18), and near recovery by age 1 year (-0.72 and -0.76). Using multivariable regression analysis, diagnosis of necrotizing enterocolitis was independently associated with significant decrements of WAZ (-0.76 ± 0.32; P = .02) and LAZ (-1.24 ± 0.32; P = .0001). ≥ 2 central line-associated bloodstream infections was also independently associated with decreases in WAZ (-0.95 ± 0.33; P = .004) and LAZ (-0.86 ± 0.32; P = .007).

CONCLUSION

In a cohort of infants with SBS, we observed a unique pattern of somatic growth, with concomitant deceleration of both WAZ and LAZ and near recovery by 1 year. Inflammatory conditions (necrotizing enterocolitis and central line-associated bloodstream infections) represent potentially modifiable risk factors for suboptimal somatic growth.

Nutritional outcomes in survivors of congenital diaphragmatic hernia (CDH)-factors associated with growth at one year

BACKGROUND

Malnutrition is prevalent among congenital diaphragmatic hernia (CDH) survivors. We aimed to describe the nutritional status and factors that impact growth over the 12-months following discharge from the pediatric intensive care unit (PICU) in this cohort.

METHODS

CDH survivors, who were discharged from the PICU from 2000 to 2010 with follow-up of at least 12months, were included. Nutritional intake, anthropometric, and clinical variables were recorded. Multivariable linear regression was used to determine factors associated with weight-for-age Z-scores (WAZ) at 12months.

RESULTS

Data from 110 infants, 67% male, 50% patch repair, were analyzed. Median (IQR) WAZ for the cohort was -1.4 (-2.4 to -0.3) at PICU discharge and -0.4 (-1.3 to 0.2) at 12-months. The percentage of infants with significant malnutrition (WAZ<-2) decreased from 26% to 8.5% (p<0.001). Patch repair (p=0.009), protein intake<2.3g/kg/day (p=0.014), and birth weight (BW)<2.5kg (p<0.001) were associated with lower WAZ at 12-months.

CONCLUSIONS

CDH survivors had a significantly improved nutritional status in the 12-months after PICU discharge. Patch repair, lower BW, and inadequate protein intake were significant predictors of lower WAZ at 12-months. A minimum protein intake in the PICU of 2.3g/kg/day was essential to ensure optimal growth in this cohort.

Metabolic bone disease in pediatric intestinal failure patients: prevalence and risk factors

PURPOSE

Patients with intestinal failure (IF) are known to have impaired absorption of nutrients required for maintenance of skeletal mass. Rates and risk factors of low bone mineral density (BMD) are unknown in pediatric IF patients.

METHODS

Following IRB approval, patients with IF having undergone DXA scans were identified and laboratory, clinical, and nutritional intake variables were recorded. Low BMD was defined by a z-score of less than or equal to -2.0. Univariate followed by multivariable regression analysis was performed.

RESULTS

Sixty-five patients underwent a total of 99 routine DXA scans. Twenty-seven (41%) had vitamin D deficiency, 22 (34%) had low BMD, and nineteen (29%) had a history of fractures. Variables noted to be associated with low BMD (p<0.1) on univariate analysis were considered for multivariable regression. Multivariable regression identified WAZ and serum calcium levels (p<0.05) as independent predictors of low BMD z-score. None of the other evaluated factors were associated with the risk of low BMD. Low BMD was not associated with risk of fractures.

CONCLUSION

There is a significant incidence of low BMD in children with IF. WAZ and lower serum calcium levels are associated with risk of low BMD. Additional long term prospective studies are needed to further characterize the risk factors associated with low BMD.

Patterns of surgical practice in very low birth weight neonates born in the United States: a Vermont Oxford Network analysis

BACKGROUND/PURPOSE

The distribution of surgical care of very low birth weight (VLBW) neonates among centers with varying specialized care remains unknown. This study quantifies operations performed on VLBW neonates nationally with respect to center type.

METHODS

VLBW neonates born 2009-2012 were assessed using a prospectively collected multi-center database encompassing 80% of all VLBW neonates in the United States. Surgical centers were categorized based on availability of pediatric surgery (PS) and anesthesia (PA).

RESULTS

48,711 major procedures (29,512 abdominal operations) were performed on 24,318 neonates. Of all patients, 20,892 (85.9%) underwent surgery at centers with PS and PA available on site. 1663 (6.8%) patients were treated at centers with neither specialty on site. Neonates requiring complex operations were more likely to receive surgery at centers with both PS and PA on staff than those requiring non-complex operations (95.6% vs 93.6%).

CONCLUSION

This study confirms that most operations on VLBW neonates in the U.S. are performed at centers with pediatric surgeons and anesthesiologists on staff. Further research is necessary, however, to elucidate why a significant minority of this challenging population continues to be managed at centers without pediatric specialists.

Mortality associated with laparotomy-confirmed neonatal spontaneous intestinal perforation: a prospective 5-year multicenter analysis

BACKGROUND

Spontaneous intestinal perforation (SIP) has been recognized as a distinct disease entity. This study sought to quantify mortality associated with laparotomy-confirmed SIP and to compare it to mortality of laparotomy-confirmed necrotizing enterocolitis (NEC).

METHODS

Data were prospectively collected on 177,618 very-low-birth-weight (VLBW, 401-1500g) neonates born between January 2006 and December 2010 admitted to US hospitals participating in the Vermont Oxford Network (VON). SIP was defined at laparotomy as a focal perforation of the intestine without features suggestive of NEC or other intestinal abnormalities. The primary outcome was in-hospital mortality.

RESULTS

At laparotomy, 2036 (1.1%) neonates were diagnosed with SIP and 4076 (2.3%) with NEC. Neonates with laparotomy-confirmed SIP had higher mortality (19%) than infants without NEC or SIP (5%, P=0.003). However, laparotomy-confirmed SIP patients had significantly lower mortality than those with confirmed NEC (38%, P<0.0001). Mortality in both NEC and SIP groups decreased with increasing birth weight and mortality was significantly higher for NEC than SIP in each birth weight category. Indomethacin and steroid exposure were more frequent in the SIP cohort than the other two groups (P<0.001).

CONCLUSIONS

In VLBW infants, the presence of laparotomy-confirmed SIP increases mortality significantly. However, laparotomy-confirmed NEC mortality was double that of SIP. This relationship is evident regardless of birth weight. The variant mortality of laparotomy-confirmed SIP versus laparotomy-confirmed NEC highlights the importance of differentiating between these two diseases both for clinical and research purposes.

Factors Affecting Spontaneous Closure of Gastrocutaneous Fistulae After Removal of Gastrostomy Tubes in Children With Intestinal Failure

BACKGROUND

Children with intestinal failure (IF) frequently require gastrostomy tubes (GTs) for long-term nutrition support. Risk factors for persistent gastrocutaneous fistulae (GCFs) in pediatric patients with IF are largely unknown but may include underlying nutrition status and duration of indwelling GT.

MATERIALS AND METHODS

Records of patients with IF having undergone GT removal and allowed a trial at spontaneous closure were reviewed. Nonparametric continuous variables were analyzed using the Wilcoxon rank sum test. Post hoc analysis was performed to identify the optimal threshold of GT duration predicting probability of spontaneous closure identified using receiver operating characteristic curve analysis.

RESULTS

Fifty-nine children with IF undergoing GT removal were identified. Spontaneous closure occurred in 36 (61%) sites, while 23 (39%) underwent operative closure at a median 67 days after GT removal. The duration of indwelling GT was significantly shorter in the spontaneous closure group (11.5 vs 21 months, P = .002). Of 33 GT indwelling for ≤ 18 months, 28 (85%) closed spontaneously, compared with only 9 of 26 (35%) with duration >18 months (P < .001). With GCF persisting beyond 7 days, only 21% (6/28) of sites closed spontaneously, but this dropped to 6% (1/18) of cases with concurrent GT duration >18 months.

CONCLUSIONS

Of the risk factors evaluated, only prolonged GT duration was associated with an increased likelihood of failure to close spontaneously. It is significantly less likely in pediatric patients with IF in whom GCF persists >7 days, particularly if the duration of GT is >18 months. Relatively earlier operative closure should be considered in this group.

Gastrointestinal bleeding as a complication of serial transverse enteroplasty

PURPOSE

Serial transverse enteroplasty (STEP) lengthens and tapers bowel in patients with intestinal failure. Evaluation and treatment of serious late gastrointestinal bleeding (GIB) in three STEP patients are described.

METHODS

Patients participating in an interdisciplinary intestinal rehabilitation program were reviewed to identify those who underwent STEP and had GIB requiring transfusion.

RESULTS

Of 296 patients, 23 underwent STEP, and 3 (13%) had subsequent GIB requiring transfusion. Diagnoses were vanishing gastroschisis/atresia, malrotation/atresia, and gastroschisis.. STEP was performed at ages 3-5 months, using 5-15 stapler-firings with an increase in mean bowel length from 39 to 62 cm. GIB was diagnosed 5-30 months post-op and resulted in 1-7 transfusions per patient. Endoscopy demonstrated staple-line ulceration in two patients and eosinophilic enterocolitis in the third. All were treated with enteral antibiotics, sulfasalazine, and luminal steroids. Those with ulcers responded to bowel rest, and the patient with eosinophilic enterocolitis stabilized with luminal steroids. In all three, hemoglobin levels improved despite persistent occult bleeding.

CONCLUSIONS

Significant GIB is a potential late complication of STEP. Endoscopy identified the underlying source of GIB in all three patients. A combination of enteral antibiotics, anti-inflammatory medications, and bowel rest was effective in treating post-STEP GIB, without the need for additional bowel resection.

Citrulline levels following proximal versus distal small bowel resection

PURPOSE

Citrulline, a nonprotein amino acid synthesized by enterocytes, is a biomarker of bowel length and the capacity to wean from parenteral nutrition. However, the potentially variant effect of jejunal versus ileal excision on plasma citrulline concentration [CIT] has not been studied. This investigation compared serial serum [CIT] and mucosal adaptive potential after proximal versus distal small bowel resection.

METHODS

Enterally fed Sprague-Dawley rats underwent sham operation or 50% small bowel resection, either proximal (PR) or distal (DR). [CIT] was measured at operation and weekly for 8 weeks. At necropsy, histologic features reflecting bowel adaptation were evaluated.

RESULTS

By weeks 6-7, [CIT] in both resection groups significantly decreased from baseline (P<0.05) and was significantly lower than the concentration in sham animals (P<0.05). There was no difference in [CIT] between PR and DR at any point. Villus height and crypt density were higher in the PR than in the DR group (P≤0.02).

CONCLUSION

[CIT] effectively differentiates animals undergoing major bowel resection from those with preserved intestinal length. The region of intestinal resection was not a determinant of [CIT]. The remaining bowel in the PR group demonstrated greater adaptive potential histologically. [CIT] is a robust biomarker for intestinal length, irrespective of location of small intestine lost.