A prospective evaluation of intestinal stenosis following necrotizing enterocolitis

Variability in antibiotic duration for necrotizing enterocolitis and outcomes in a large multicenter cohort

OBJECTIVES

To evaluate variability in antibiotic duration for necrotizing enterocolitis (NEC) and associated clinical outcomes.

STUDY DESIGN

Five-hundred ninety-one infants with NEC (315 medical; 276 surgical) were included from 22 centers participating in Children's Hospitals Neonatal Consortium (CHNC). Multivariable analyses were used to determine predictors of variability in time to full feeds (TFF) and length of stay (LOS).

RESULTS

Median (IQR) antibiotic duration was 12 (9, 17) days for medical and 17 (14, 21) days for surgical NEC. Wide variability in antibiotic use existed both within and among centers. Duration of antibiotic therapy was associated with longer TFF in both medical (OR 1.04, 95% CI [1.01, 1.05], p < 0.001) and surgical NEC (OR 1.02 [1, 1.03] p = 0.046); and with longer LOS in medical (OR 1.03 [1.02, 1.04], p < 0.001) and surgical NEC (OR 1.01 [1.01, 1.02], p = 0.002).

CONCLUSION

Antibiotic duration for both medical and surgical NEC remains variable within and among high level NICUs.

Earlier re-initiation of enteral feeding after necrotizing enterocolitis decreases recurrence or stricture: a systematic review and meta-analysis

OBJECTIVE

To assess the effects of earlier vs. later re-initiation of enteral feeds after necrotizing enterocolitis (NEC).

STUDY DESIGN

We reviewed the literature to assess timing of enteral feeding after NEC using fixed effects models.

RESULTS

Three studies met inclusion criteria; no randomized trials. After removal of Bell's Stage I infants, the earlier refeeding group (<5-7 or median 4 days) included 79 infants and later refeeding group (≥5-7 or median 10 days) included 119 infants. Pooled analysis revealed earlier re-initiation reduced the incidence in the composite outcome of recurrent NEC and/or post-NEC stricture (OR = 0.27; 95% Cl = 0.10-0.75; p = 0.012). Individually, NEC recurrence (pooled OR = 0.34; 95% Cl = 0.09-1.29; p = 0.112) or stricture (OR = 0.34; 95% Cl = 0.09-1.26; p = 1.06) did not differ between groups.

CONCLUSIONS

There was no increase in negative outcomes with earlier refeeding after NEC. Earlier initiation of enteral feeds resulted in a significantly lower risk for the combined outcome of recurrent NEC and/or post-NEC stricture.

Long Term Outcome of Infants with NEC

Necrotizing enterocolitis (NEC) is an important complication for premature newborns. Infants who survive NEC have a greater possibility of poor long-term physiological and neurodevelopmental growth. The objective of this paper is to give a comprehensive description of the long-term consequences of NEC. Despite the rise in incidence of NEC there is a scarcity of data regarding long-term outcomes of these infants that can be divided into two groups. The first group includes gastrointestinal complications that could occur in relation to the bowel disease, the surgical treatment and quality of the residual bowel. These complications are strictures and short bowel syndrome (SBS). Intestinal strictures are a common occurance after recovery from NEC that should be investigated with a contrast study in case of suspicious clinical findings of bowel obstruction or before reversal ostomy. After this diagnostic investigation, if a stricture is detected in a symptomatic patient, resection of the affected loop of bowel with anastomosis is required. SBS is the result of a massive intestinal resection or of a dysfunctional residual bowel and it can occur in a fourth of patients affected by NEC. The second group includes neurodevelopmental impairment and growth. Neurodevelopmental outcomes of patients after NEC recovery have not been widely reported. Infants with NEC is a population of patients at high risk for adverse neurodevelopmental outcomes whose cause can be multifactorial and linked to perinatal events, severity of disease, surgical treatment and its complications and hospitalization. Understanding the morbidity of NEC with a longterm follow-up would aid neonatologists and pediatric surgeons to make informed decisions in providing care for these patients. Further research on this topic is needed.

Infant progressive colonic stenosis caused by antibiotic-related Clostridium difficile colitis - a case report and literature review

BACKGROUND

Colonic stenosis is a rare cause of pediatric intestinal obstruction. The root cause underlying colonic stenosis is unclear and there is no fixed operation.

CASE PRESENTATION

We reported on a male infant with progressive colonic stenosis caused by antibiotic-related colitis. The infant was admitted to our hospital with pneumonia but developed progressive abdominal distension and diarrhea following antibiotic treatment with meropenem. Initial testing of stool culture showed a Clostridium difficile infection. Additional testing with barium enema imaging showed stenosis at the junction of the sigmoid and descending colon at first and another stenosis occurred at the right half of the transverse colon 3 weeks later. Staged surgical treatment was performed with primary resections of the two parts suffering stenosis, ileostomy, and secondary intestinal anastomosis. A pathological exam then confirmed the diagnosis of colonic stenosis and the patient had an uneventful recovery and has been recovering well as evidenced by the 1-year follow-up.

CONCLUSIONS

Based on a review of the literature and our case report, we found that progressive colonic stenosis caused by colitis due to antibiotic-related Clostridium difficile infection is rare in infants. Infants with colitis and repeated abdominal distention, vomiting, and constipation should be treated with the utmost caution and screened. Despite this, clinical manifestations depended on the severity of the stenosis. Barium enema, colonoscopy, laprascopy or laparotomy and colonic biopsy are helpful for diagnosis and differential diagnosis. While both one-stage and multiple-stage operations are feasible, a staged operation should be used for multiple colonic stenoses.

Time to reintroduction of feeding in infants with nonsurgical necrotizing enterocolitis

BACKGROUND

For infants with necrotizing enterocolitis (NEC) treated nonoperatively, no consensus exists on the optimal fasting period prior to reintroducing feeds after NEC. We report our experience with early (<7days) and late (≥7days) refeeding in this population.

METHODS

A chart review of infants with NEC born between 2006 and 2016 was performed. Data elements include demographics, comorbidities, day of diagnosis, Bell's stage, recurrence, strictures, length of stay and mortality, and were grouped into early and late refeeding. T-tests were used for means and chi-squared tests for distribution of proportions. Linear and logistic regressions were used to further evaluate the association of length of stay, stricture, recurrence, and death with time to refeeding.

RESULTS

Of 228 NEC patients, 149(65%) were treated nonoperatively (Bell Stages I, IIA, IIB, IIIA). Eleven patients were excluded owing to never restarting feeds, largely secondary to early death. The early (n=40) and late refeeding (n=98) groups were not significantly different with regard to mean gestational age at birth, race, birth weight, day of life at NEC diagnosis, or cardiac disease. NEC Stage was significantly different (p<0.001). The late group had significantly more Stage IIB patients (p=.02), and the early group had more stage I patients (p=<0.01). After adjusting for Bell's stage, the odds of NEC recurrence, death, and the composite outcome of recurrence or stricture or death were not significantly different between early and late groups.

CONCLUSIONS

No standardized guidelines exist for restarting enteral nutrition following medical NEC. In patients managed nonoperatively, early reintroduction of feeding was not significantly associated with increased NEC recurrence, mortality, or stricture.

LEVEL OF EVIDENCE

Treatment Study - Level III.

Predictive factors and clinical practice profile for strictures post-necrotising enterocolitis

Intestinal stricture is a severe and common complication of necrotizing enterocolitis (NEC), causing severe and prolonged morbidity. Our goal was to investigate the clinical predictors for strictures developing after NEC and evaluate the management outcome of the post-NEC strictures to better orient their medicosurgical care.A total of 188 patients diagnosed with NEC with identical treatment protocols throughout the period under study were retrospectively reviewed from 4 academic neonatal centers between from January 1, 2011, and October 31, 2016. Clinical predictive factors and clinical outcomes, including demographic information, clinical management, laboratory data, histopathology of resected bowel segment, and discharge summaries, were evaluated on the basis of with post-NEC strictures or not.Of the involved variables examined, the late-onset NEC [risk ratio (RR), 0.56; 95% confidence interval (95% CI), 0.41-0.92; P < 0.001], cesarean delivery (RR, 1.42; 95% CI, 0.98-2.29; P = 0.026), and first procalcitonin (PCT) (onset of symptoms) (RR, 1.82; 95% CI, 0.98-3.15; P = 0.009) were the independent predictive factors for the post-NEC strictures. C-reactive protein (CRP), white blood cell (WBC), and plateletcrit levels were markedly higher on infants with stricture and elevated levels were maintained until the stricture was healed. Infants with intestinal stricture had significantly longer times to beginning enteral feeds (23.9 ± 12.1), than infants without intestinal stricture (18.6 ± 8.8) (P = 0.023). The median age at discharge was also significantly higher in the group with stricture (P = 0.014).This retrospective and multicenter study demonstrates that the early-onset NEC and cesarean delivery conferred protection over the post-NEC stricture. Infants with post-NEC stricture need prolonged hospitalization.

Complications in neonatal surgery

Neonatal surgery is recognized as an independent discipline in general surgery, requiring the expertise of pediatric surgeons to optimize outcomes in infants with surgical conditions. Survival following neonatal surgery has improved dramatically in the past 60 years. Improvements in pediatric surgical outcomes are in part attributable to improved understanding of neonatal physiology, specialized pediatric anesthesia, neonatal critical care including sophisticated cardiopulmonary support, utilization of parenteral nutrition and adjustments in fluid management, refinement of surgical technique, and advances in surgical technology including minimally invasive options. Nevertheless, short and long-term complications following neonatal surgery continue to have profound and sometimes lasting effects on individual patients, families, and society.

The value of contrast studies in the evaluation of bowel strictures after necrotising enterocolitis

PURPOSE

Strictures of the bowel are a frequent complication post-necrotising enterocolitis (NEC). Contrast studies are routinely performed prior to stoma closure following NEC. The aim of this study was to evaluate the ability of these studies to detect strictures and also directly compare them to operative and histological findings.

METHODS

Two hundred and fourteen neonates who had a diagnosis of NEC (Bell stage 2 or greater) in a single unit (2007-2011) were analysed. Their case notes, radiology, and histology were reviewed.

RESULTS

One hundred and sixteen neonates underwent an emergency laparotomy and 77 had stomas fashioned. Sixty-six patients had a contrast study prior to stoma closure (distal loopogram 18, contrast enema 37, both studies 11). Colonic strictures were reported in 18 patients and small bowel strictures were reported in two patients. Fourteen of these colonic strictures were confirmed at operation and on histology but three colonic strictures were missed on contrast studies; one patient had had both contrast studies and the other two only a distal loopogram. Two small bowel strictures reported were confirmed and an additional small bowel stricture missed on distal loopogram was also detected at the time of operation. The incidence of post-op strictures was 19 out of 68 patients (27.9 %) and 16 (84.2 %) of these strictures were found in the colon. Contrast enemas had a much higher sensitivity for detecting post-NEC colonic strictures than distal loopograms; 93 versus 50 %, respectively; however, they are more likely to give a false positive result and therefore their specificity is lower; 88 versus 95 %, respectively.

CONCLUSION

Colon is the commonest site for post-NEC stricture and contrast enema is the study of choice for detecting these strictures prior to stoma closure.

Necrotizing enterocolitis: controversies and challenges

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

Utility of gastrointestinal fluoroscopic studies in detecting stricture after neonatal necrotizing enterocolitis

OBJECTIVES

We report our institution's 5-year experience with upper gastrointestinal study with small bowel follow-through (UGI-SBFT) and contrast enema (CE) for the diagnosis of a post-necrotizing enterocolitis (NEC) stricture. We hypothesized that sensitivity and specificity of UGI-SBFT and CE were <85% in diagnosing a post-NEC stricture.

METHODS

A retrospective observational cohort study was performed. Included patients were neonates diagnosed as having Bell's modified stage 2 or 3 NEC who had undergone UGI-SBFT and/or CE to evaluate for a stricture. Exploratory laparotomy was used to definitively determine the stricture presence, which was confirmed by pathology. An infant was categorized as having no stricture if no surgical intervention occurred or if no stricture was reported on pathology following surgical resection.

RESULTS

A total of 56 patients met inclusion criteria, with 51 UGI-SBFT and 85 CE performed. A total of 25 patients were diagnosed as having a stricture. For small bowel (SB) strictures, CE compared with UGI-SBFT has a higher sensitivity (0.667 vs 0.00) and a similar specificity (0.857 vs 0.833). For SB and/or colonic strictures, CE has a sensitivity of 0.667 and a specificity of 0.951. Strictures were more likely to be found on imaging in symptomatic infants compared with those in asymptomatic infants (28% vs 8%, P = 0.002).

CONCLUSIONS

CE should be the initial study in the diagnostic workup for a post-NEC stricture because this test has a higher likelihood of detecting a stricture if it is present. As a result of low sensitivity of UGI-SBFT and/or CE in the diagnosis of a post-NEC stricture, a negative study should not rule out the diagnosis of a stricture in persistently symptomatic patients.

Necrotizing enterocolitis (NEC) and the risk of intestinal stricture: the value of C-reactive protein

Necrotizing enterocolitis (NEC) is a severe complication frequently seen during the neonatal period associated with high mortality rate and severe and prolonged morbidity including Post-NEC intestinal stricture. The aim of this study is to define the incidence and risk factors of these post-NEC strictures, in order to better orient their medicosurgical care. Sixty cases of NEC were retrospectively reviewed from a single tertiary center with identical treatment protocols throughout the period under study, including systematic X-ray contrast study. This study reports a high rate of post-NEC intestinal stricture (n = 27/48; 57% of survivors), either in cases treated surgically (91%) and after the medical treatment of NEC (47%). A colonic localization of the strictures was more frequent in medically-treated patients than in those with NEC treated surgically (87% vs. 50%). The length of the strictures was significantly shorter in case of NEC treated medically. No deaths were attributable to the presence of post-NEC stricture. The mean hospitalization time in NICU and the median age at discontinuation of parenteral nutrition were longer in the group with stricture, but this difference was not significant. The median age at discharge was significantly higher in the group with stricture (p = 0.02). The occurrence of post-NEC stricture was significantly associated with the presence of parietal signs of inflammation and thrombopenia (<100 000 platelets/mm³). The mean maximum CRP concentration during acute phase was significantly higher in infants who developed stricture (p<0.001), as was the mean duration of the elevation of CRP levels (p<0.001). The negative predictive value of CRP levels continually <10 mg/dL for the appearance of stricture was 100% in our study. In conclusion, this retrospective and monocentric study demonstrates the correlation between the intensity of the inflammatory syndrome and the risk of secondary intestinal stricture, when systematic contrast study is performed following NEC.

Single-incision pediatric endosurgery-assisted ileocecectomy for resection of a NEC stricture

A single-incision pediatric endosurgery (SIPES) has not been typically used for operations in premature infants yet. We report a case of a 3-month-old 25-week premature infant who underwent SIPES-assisted ileocecal resection for a stricture after medically treated necrotizing enterocolitis. The patient recovered uneventfully, and was discharged on full feeds 15 postoperatively with virtually no appreciable scar. SIPES is a reasonable alternative for NEC stricture resection in premature infants. Prematurity should not be considered a contraindication to single-incision endosurgery.

Early enteral feeding in conservatively managed stage II necrotizing enterocolitis is associated with a reduced risk of catheter-related sepsis

AIMS

To compare the effect of fasting period duration on complication rates in neonates managed conservatively for necrotizing enterocolitis (NEC) Bell stage II.

METHODS

We conducted a multicenter study to analyze retrospectively multiple data collected by standardized questionnaire on all admissions for NEC between January 2000 and December 2006. NEC was staged using modified Bell criteria. We divided the conservatively managed neonates with NEC Bell stage II into two groups (those fasted for <5 days and those fasted for >5 days) and compared the complication rates.

RESULTS

Of the 47 conservatively managed neonates Bell stage II, 30 (64%) fasted for <5 days (range 1-4 days) and 17 (36%) for >5 days (range 6-16 days). There were no significant differences for any of the patient characteristics analyzed. One (3%) and four (24%) neonates, respectively, developed post-NEC bowel stricture. One (3%) and two neonates (12%) suffered NEC relapse. None and five (29%) neonates developed catheter-related sepsis.

CONCLUSION

Shorter fasting after NEC appears to lower morbidity after the acute phase of the disease. In particular, shorter-fasted neonates have significantly less catheter-related sepsis. We found no benefit in longer fasting.

Necrotizing Enterocolitis: Review of State-of-the-Art Imaging Findings with Pathologic Correlation

Plain abdominal radiography is the current standard imaging modality for evaluation of necrotizing enterocolitis (NEC). Sonography is still not routinely used for diagnosis and follow-up, as it is not widely recognized that it can provide information that is not provided by plain abdominal radiography and that may affect the management of NEC. Like plain abdominal radiography, sonography can depict intramural gas, portal venous gas, and free intraperitoneal gas. However, the major advantages of abdominal sonography over plain abdominal radiography are that it can depict intraabdominal fluid, bowel wall thickness, and bowel wall perfusion. Sonography may depict changes consistent with NEC when the plain abdominal radiographic findings are nonspecific and inconclusive. Thinning of the bowel wall and lack of perfusion at sonography are highly suggestive of nonviable bowel and may be seen before visualization of pneumoperitoneum at plain abdominal radiography. The mortality rate is higher after perforation; thus, earlier detection of severely ischemic or necrotic bowel loops, before perforation occurs, could potentially improve the morbidity and mortality in NEC. The information provided by sonography allows a more complete understanding of the state of the bowel in patients with NEC and may thus make management decisions easier and potentially change outcome.

Abdominal drain placement versus laparotomy for necrotizing enterocolitis with perforation

Perforated NEC in the fragile, premature infant remains a complex neonatal and surgical problem. Future investigation into the basic mechanisms of the intestinal inflammatory response in the premature neonate may allow for preventive strategies in the management of NEC. Until then, surgical management for perforated NEC will remain a necessary intervention to treat the complications of this disease. The two most commonly used surgical strategies for perforated NEC are laparotomy, bowel resection, and enterostomy versus primary peritoneal drainage. There are no compelling, prospective, controlled data supporting one procedure over the other. Although there are several surgical options for treating perforated NEC, definitive evidence-based guidelines for the best surgical treatment in terms of survival outcome remain to be determined.

A case of ischemic jejunal stricture after surgical reduction of intussusception

A 15-year-old girl presented with small bowel obstruction due to ischemic jejunal stricture which developed three weeks after successful surgical reduction of an intussusception with a Peutz-Jeghers-type polyp as a lead point. The reduced jejunum had no macroscopic injury, and the stricture caused complete obstruction requiring jejunal resection.

Congenital membranous colonic stenosis--case report of an extremely rare anomaly

Congenital colonic stenosis is a rare anomaly. Congenital membranous colonic stenosis is more rare. The authors experienced a case of congenital membranous colonic stenosis that was diagnosed and treated successfully. To the authors' knowledge, congenital membranous colonic stenosis has not been reported previously in the literature.

Z-shaped anastomosis for the treatment of a benign rectosigmoid stricture

A girl with malrotation underwent a Ladd's operation at 35 days of age and later had an adhesiotomy at 115 days of age. After the adhesiotomy, she suffered from sepsis and subsequent disseminated intravascular coagulation (DIC). At 178 days of age, she developed an intestinal obstruction because of a rectosigmoid stricture probably caused by DIC-associated ischemia. As a result, an ileostomy was performed. At one year, 4 months of age, she underwent a resection of the proximal part of the rectosigmoid stricture and a reconstruction by means of a Z-shaped anastomosis. Based on our experience, Z-shaped anastomosis appears to be an excellent treatment not only for Hirschsprung's disease but also for benign rectosigmoid stricture.

An unusual late complication of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) now is managed frequently successfully without surgical intervention. NEC may result in strictures, which present after the acute inflammatory process has resolved. Strictures usually present as obstruction in the first year or two of life. A case report is presented of an 11-year-old child who had symptoms from a previously undiagnosed NEC stricture as a result of pica when coins obstructed the stricture. As treatment of NEC continues to improve, more and later complications of this disease can be expected. J Pediatr Surg 36:1853-1854.

[Intestinal stenosis during ulceronecrotizing enterocolitis]

BACKGROUND

Intestinal stenosis following necrotizing enterocolitis (NE) occurred both in surgically-treated neonates after perforation, distal to an enterostomy and in medically-treated patients developing symptoms of obstruction. It has been proposed to detect stenosis by contrast enema before refeeding in those medically-treated patients. The aim of this study was to compare delay, clinical and pathological characteristics of surgical and medical patients, both after occlusion and prospective contrast studies.

PATIENTS AND METHODS

Fifteen patients out of 50 with NE observed from 1984 to 1994 developed one or several intestinal stenosis. Diagnosis of NE was based on usual clinical signs, X-ray pneumatosis (43 to 50) and/or perforation in 16 cases. Among these 16 surgical patients, 12 survived the initial perforation. Among the 34 medical patients, 11 were seen before 1989 and did not have contrast studies before refeeding; 23 seen after 1989 had a contrast enema before.

RESULTS

One or several stenosis occurred in four out of 12 surgical patients, four out of 11 medical patients without prospective contrast studies (one of them died from sepsis) and seven out of the 23 of the prospective group. On the whole, 26 stenosis occurred in 15 neonates: ten to the right colon, five to the transverse and 11 to the left colon. One ileal stenosis followed enterostomy. Delay of stenosis development was comparable in the three groups (between 3 weeks and 3 months). Pathologic examination showed similar lesions in the three groups (fibrosis 15, edema nine to 15 and chronic inflammation 12 to 15).

CONCLUSION

Among 46 neonates who survived the initial period, 15 developed stenosis, a 30% proportion similar in patients operated on for perforation or in medically-treated patients whose diagnosis was made after occlusion or after contrast enema as well. These results suggest that systematic stenosis detection by contrast enema may avoid complications and permit programmed one-stage surgery.

[Increasing frequency and diagnostic difficulties in intestinal stenosis after necrotizing enterocolitis]

BACKGROUND

Stenosis after necrotizing enterocolitis (NEC) has increased from 15 to 57% over the last 10 years in our unit. The aim of this study is to point out the difficulty of diagnosis and treatment, and search for factors explaining this increase.

PATIENTS AND METHODS

From 1986 to 1991, 42 newborns had NEC, followed by intestinal strictures in 19 of them (57% of the 33 survivors). Data from these 19 patients were compared with those of the 14 without intestinal strictures. The 33 survivors were also compared with those of an earlier study including 25 NEC seen from 1979 to 1986.

RESULTS

After medical treatment (n = 12), intestinal stenosis led to occlusion after three weeks, was located to both small and large intestine and was short and tight. After surgical treatment (n = 7), stenosis was shown by opacification before digestive anastomosis (n = 5) or revealed by occlusion (n = 2); it stayed on the colon, was long or multiple, requiring extensive resections. No difference could be found between data from patients with or without stenosis. Although newborns were actually more premature, the risk of stenosis was more frequent when newborns of same gestational ages and/or weights were compared.

CONCLUSIONS

Intestinal stenosis is a frequent complication after NEC; its diagnosis is often difficult and requires extensive digestive resections. No clinical or therapeutic factor could be found to explain the actual increase in frequency.

Late intestinal strictures following successful treatment of necrotizing enterocolitis

Between 1975 and 1992, in 16 infants (14%) out of 113 neonates with previous necrotizing enterocolitis (NEC) a total of 25 intestinal strictures had to be treated. Four (16%) were found in the ileum and 21 (84%) in the colon, and in 50% multiple strictures were present. In these 16 patients initial treatment for acute NEC included conservative treatment in 5, primary resection and enterostomies in 6 and proximal diverting enterostomies in 5. Therefore, the incidence of late strictures was 11% after conservative therapy, 11% after primary resection and 55% after primary proximal diverting enterostomies. An average of 49 days elapses between the recovery from NEC and the diagnosis of late strictures in conservatively treated patients. After initial surgical treatment, late strictures were detected on contrast studies on an average of 80 days. In pathologic specimens, marked fibrosis in the submucosa was consistently present in all strictures, whereas inflammatory changes in the mucosa, disruption or hypertrophy of the muscle layers or absence of ganglion cells were seen less frequently. All strictures were resected and primary end-to-end anastomosis was performed. But despite the development of late intestinal strictures, bowel preservation was improved after initial restrictive surgical therapy and aggressive medical treatment.

Necrotizing enterocolitis in infancy

The most common gastrointestinal emergency in the newborn is necrotizing enterocolitis. Premature babies are the most likely victims, but it also occurs in full-term infants. Although great strides have been made in elucidating some of the factors responsible for necrotizing enterocolitis, such as intestinal ischemia, bacterial overgrowth, and feeding dysfunction, the exact etiology is as yet unclear. The timing and indications for surgery differ from institution to institution, but the long-term outcome is similar in most large series. The overall mortality rate remains about 20% to 40%, and of the survivors, about one half seem to have no sequelae, the remaining infants having neurologic and gastrointestinal deficits of various degrees of significance.

Colonic strictures following successful medical management of necrotizing enterocolitis: a prospective study evaluating early gastrointestinal contrast studies

This is a prospective study of 50 patients with neonatal necrotizing enterocolitis (NEC) treated successfully by medical means. They were all screened with an upper gastrointestinal (GI) contrast study after 14 days of healing and prior to establishment of feeding. Thirty-six patients (72%) with normal upper GI examinations responded well to a graduated increase in feeding. Another 5 (10%) with questionable areas on their upper GI examination had a normal follow-up contrast enema. Feeding was successfully established in this group of infants also. The remaining 9 patients (18%) had demonstrable strictures in both contrast studies. After elective resection of strictures with restoration of intestinal continuity, they were also fed successfully. No delayed strictures were seen in any of the patients. We propose that this method of evaluation is safe, efficient and reliable in the diagnosis of strictures that develop in patients recovering from NEC.

A scoring system in predicting the risk of intestinal stricture in necrotizing enterocolitis

Of 46 infants with a diagnosis of necrotizing enterocolitis (NEC) admitted to the neonatal intensive care unit over the period 1981-1985, 40 have been followed from 2 to 6 years after the acute episode. A contrast enema (CE) to look for intestinal strictures (IS) was performed either during the first months in surgically managed patients, or between 2 and 6 years in asymptomatic patients. Clinical, laboratory and radiology parameters collected during the 7 days following NEC were used to establish a score which was correlated with radiological data obtained after CE. Of the 40 infants, 17 developed symptomatic or asymptomatic IS and 16 of these 17 infants has a score greater than or equal to 7. Nineteen of the 23 patients without IS had a score less than 7. We conclude that the proposed score established on day 8 after onset of NEC helps to identify infants at higher risk of developing IS and for whom closer follow up appears necessary.

Necrotizing enterocolitis of the neonate

Necrotizing enterocolitis is the most common gastrointestinal emergency in the newborn. The syndrome strikes premature infants during the first 2 weeks of life. Abdominal distention, lethargy, and feeding intolerance are early signs of NEC that may progress to gastrointestinal bleeding and hemodynamic instability. The radiographic hallmark of NEC is pneumatosis intestinalis (air in the bowel wall). The ileum and colon are the usual sites of crepitant intestinal necrosis, leading frequently to perforation. In spite of appropriate medical therapy, about half of the infants with NEC develop intestinal gangrene or perforation and require surgery, consisting of bowel resection and enterostomy formation. The most common late complication, intestinal stricture, occurs in 15 to 35 per cent of recovered infants. Overall mortality from NEC ranges from 20 to 40 per cent. The etiology of NEC is poorly understood and is considered to be multifactorial, related to ischemia, bacterial colonization, and formula feedings in a susceptible infant. Future progress in the treatment of NEC may be achieved by earlier detection of necrosis, modification of gastrointestinal flora, or by bolstering the deficient gastrointestinal immune mechanisms of the premature neonate.

Late onset bowel stenoses after neonatal necrotizing enterocolitis

In 14 cases of bowel stenoses occurring after neonatal necrotizing enterocolitis (NEC), eight cases presented early, within 8 weeks from the onset of NEC and three beyond 4 months. In the other three cases the stenoses occurred in defunctionalized loops. The late onset stenoses remained undiagnosed until they presented with acute, life-threatening complications, and one of these patients died. We draw attention to these late onset stenoses which could be missed in early contrast studies, and recommend a study at 4 months rather than at 4 weeks, as previously recommended. Those presenting early should not be missed, as all of our cases presented with acute and obvious intestinal obstructions, and they were all still in hospital or undergoing frequent review.

Hexosaminidase: a marker for healing after ischemic gut injury

Serum hexosaminidase activity (HEX) is elevated with ischemic gut injury. To determine if subsequent decreases in HEX correlate with gut healing, 97 weanling rats were subjected to laparotomy at which alternate vascular bundles were ligated along the base of the entire anterior mesenteric artery arcade. Fifteen rats served as preoperative controls. After recovery, rats were allowed ad lib food and water. Groups were then killed at intervals, blood was drawn for HEX determination, and samples of small bowel were taken for histological evaluation. Microscopically, focal ischemic necrosis began at 6 hr. Between 12 and 48 hr, cellular changes were consistent with progressive ischemic injury. Evidence of healing was apparent beginning at 5 days and these histological changes correlated with changes in HEX. Thus HEX proves useful as a marker for gut healing in this model.

Balloon catheter dilatation of focal intestinal strictures following necrotizing enterocolitis

Dilatation with a balloon catheter was successfully employed for 9 focal intestinal strictures which occurred in 5 infants following necrotizing enterocolitis. Eight of the 9 strictures were located in defunctionalized colon distal to an enterostomy; no infant had clinical intestinal obstruction. Because the dilatation achieved distal patency, subsequent closure of the enterostomy was accomplished without a formal laparotomy. The balloon dilatation technique may be valuable in the management of focal strictures that are not causing clinical intestinal obstruction.

Routine contrast enemas for diagnosing and managing strictures following nonoperative treatment of necrotizing enterocolitis

A study to determine the value of contrast enemas in diagnosing and managing intestinal strictures following nonoperative treatment of necrotizing enterocolitis was performed from 1978 through 1983. From 1974 through 1977, 17 patients survived nonoperative treatment of NEC and three developed symptomatic strictures, an incidence of 18% (3/17). Since then a total of 31 infants were treated for NEC; three patients survived operation for perforation and there were seven deaths, leaving 21 in the study group. Sixteen patients had contrast enemas three to six weeks after resolution of NEC, which revealed strictures in five patients. Four of the five patients with strictures demonstrated on contrast enema were without obstructive symptoms. Three of the four remained asymptomatic without treatment, and one eventually required surgery for intestinal obstruction. The fifth patient developed intestinal obstruction while still in the nursery and a contrast study demonstrated an ileal stricture. A sixth patient had a normal contrast study and developed intestinal obstruction from an ileal stricture. The incidence of strictures was 38% (6/16). In five patients, appointments for contrast studies were not kept, although clinical follow-up was complete in all. The incidence of symptomatic strictures for the contrast study period was therefore 14% (3/21). Although some authors have recommended routine contrast enemas in patients surviving nonoperative treatment of NEC, contrast enemas had no advantage over clinical follow-up in the management of patients in this study. We have discontinued the use of routine contrast enemas in favor of close follow-up and careful instruction to parents as to the early signs of intestinal obstruction.