Meconium-related ileus in extremely low-birthweight neonates: etiological considerations from histology and radiology

Postneonatal mortality of severely small for gestational age extremely low birth weight infants

BACKGROUND

Infants born with weights below the 10th percentile of the expected birth weight for gestational age, defined as small for gestational age (SGA), have an increased risk of neonatal mortality and prematurity-related complications. However, the relationship between SGA and postneonatal (28 days to <1 year) mortality among extremely low birth weight infants (ELBWIs) remains uncertain. Hence, this study aimed to investigate the association between birth weight percentiles and postneonatal mortality in ELBWIs.

METHODS

A cohort of ELBWIs with a gestational age greater than 23 weeks who were admitted to Osaka Women's and Children's Hospital between 2008 and 2019 were considered eligible. Infants with major congenital anomalies, those large for their gestational age, or those who died within 28 days of birth were excluded. Baseline characteristics and outcomes of the three groups of ELBWIs-severe SGA (sSGA; birth weight, <3rd percentile), moderate SGA (mSGA; birth weight, 3rd to <10th percentile), and appropriate for gestational age (AGA; birth weight, 10th to <90th percentile)-were compared. Logistic regression analysis was used to identify perinatal factors associated with postneonatal mortality in sSGA infants.

RESULTS

sSGA ELBWIs demonstrated higher incidence of meconium obstruction (25% vs. 8.3% vs. 7.6%, P < 0.001), cholestasis (21% vs. 4.2% vs. 9.7%, P < 0.003), and postneonatal mortality (7.3% vs. 0% vs. 0.7%, P < 0.004) than mSGA and AGA ELBWIs. In the logistic regression analysis, cholestasis (odds ratio, 30.1; 95% confidence interval, 2.98-304) and sepsis (odds ratio, 13.5; 95% confidence interval, 1.06-173) were significantly related to postneonatal mortality among ELBWIs with sSGA. The leading cause of postneonatal mortality in sSGA ELBWIs was liver failure (55.5%).

CONCLUSION

sSGA ELBWIs exhibited a higher rate of postneonatal mortality compared to mSGA and AGA ELBWIs. Therefore, strategies aimed at preventing liver dysfunction in severely cholestatic ELBWIs with sSGA are necessary.

Clinical and growth outcomes after meconium-related ileus improved with Gastrografin enema in very low birth weight infants

Background

Meconium-related ileus in very low birth weight infants can lead to increased morbidity or mortality and prolonged hospitalization without prompt diagnosis and treatment. This study primarily aimed to identify the incidence of and factors associated with meconium-related ileus and secondarily sought to investigate clinical and growth outcomes after water-soluble contrast media (Gastrografin) enema.

Methods

We retrospectively reviewed medical records of very low birth weight infants born between February 2009 and March 2019 in the neonatal intensive care unit of a single medical center. Perinatal factors, clinical outcomes, and growth outcomes were compared between the group with meconium-related ileus that received Gastrografin enema and the control group.

Results

Twenty-four (6.9%) patients were diagnosed with meconium-related ileus among 347 very low birth weight infants. All achieved successful evacuation of meconium with an average of 2.8 (range: 1–8) Gastrografin enema attempts without procedure-related complications. Initiation of Gastrografin enema was performed at mean 7.0 days (range: 2–16) after birth. Incidences of moderate to severe bronchopulmonary dysplasia were higher and the duration of mechanical ventilation and need for oxygen were longer in the meconium-related ileus group (P = 0.039, 0.046, 0.048, respectively). Meconium-related ileus infants took more time to start enteral feeding and the nothing per oral time was longer (P = 0.001 and 0.018, respectively). However, time to achieve full enteral feeding and Z-scores for weight and height at 37 weeks and at 6 months corrected age did not differ between the two groups.

Conclusions

Gastrografin enema in very low birth weight infants with meconium-related ileus was an effective and safe medical management. Following Gastrografin enema, very low birth weight infants with meconium-related ileus achieved similar subsequent feeding progress and similar growth levels as the control groups without meconium-related ileus.

Optimum therapeutic strategy for meconium-related ileus in very-low-birth-weight infants

BACKGROUND/PURPOSE

therapeutic strategy for meconium-related ileus (MRI) in very-low-birth-weight infants (VLBWs) has not been established. This study aims to clarify the optimum therapeutic strategy for MRI in VLBWs.

METHODS

MRI was defined as delayed meconium excretion and microcolon on contrast enema with Gastrografin (diatrizoate acid). Forty-two infants with MRI were treated at our institution between 2009 and 2019, and are reviewed here. They were classified into two groups: in group A (n=21), Gastrografin regurgitated into the dilated intestine during the first or second round of Gastrografin enema (GaE), while in group B (N = 21), Gastrografin did not regurgitate. Laparotomy was indicated if the intestine was perforated, or if abdominal distention was not relieved by two rounds of GaE.

RESULTS

in group A, meconium was excreted in all cases within 24 h after GaE, and no cases required laparotomy. In group B, twelve cases (57%) underwent laparotomy (P < 0.01), six cases in this group (29%), showed free air on X-ray images (P < 0.01). The median hospital stay in groups A and B were 89.0 and 136.5 days, respectively (P < 0.05). Overall mortality was 2.4%.

CONCLUSIONS

early therapeutic diagnosis by GaE followed by early surgery is suggested as the optimum strategy for MRI in VLBWs.

Discrepancy between the survival rate and neuropsychological development in postsurgical extremely low-birth-weight infants: a retrospective study over two decades at a single institution

PURPOSE

Necrotizing enterocolitis (NEC), focal intestinal perforation (FIP), and meconium-related ileus (MRI) are major diseases that cause gastrointestinal disorders in extremely low-birth-weight infants (ELBWIs). We conducted a review to compare the postoperative outcomes of ELBWIs with these diseases in our neonatal intensive-care unit.

METHODS

A retrospective chart review of ELBWIs surgically treated for NEC (n = 31), FIP (n = 35), and MRI (n = 16) in 2001-2018 was undertaken. This period was divided into early (2001-2005), middle (2006-2010), and late (2011-2018) periods. Data were analyzed with the Cochran-Armitage test. Statistical significance was defined as p < 0.05.

RESULTS

The survival rates in ELBWIs with NEC (early/middle/late: 36.4%/42.9%/61.5%; p = 0.212) and FIP (20%/50%/70.6%; p = 0.012) improved over time; all patients with MRI survived. The neuropsychological development of 24 cases was assessed with the Kyoto Scale of Psychological Development in the Postural-Motor, Cognitive-Adaptative, and Language-Social domains. The mean developmental quotient of all domains was 68.4 (range 18-95) at corrected 1.5 years of age and 69.1 (range 25-108) at chronological 3 years of age, both were considered as poor development. There was no improvement over time (p = 0.899).

CONCLUSION

Ideal neuropsychological development was not observed with the improvement of survival rate. Less-invasive surgical intervention and adequate postoperative care are required to encourage further development.

Risk Factors for Mortality and Neurodevelopmental Impairment among Neonates Born at 22-23 Weeks' Gestation

INTRODUCTION

We aimed to evaluate the risk factors for mortality and neurodevelopmental impairment (NDI) among infants of 22-23 weeks' gestational age, which currently remain unclear.

METHODS

This retrospective case-control study included 104 infants delivered at 22-23 weeks' gestation at Kagoshima City Hospital from 2006 to 2015. We compared 65 and 34 cases of survival to discharge and postnatal in-hospital death (5 excluded), respectively, and 26 and 35 cases with and without NDI, respectively, using maternal, prenatal, and postnatal records. A high rate of survivors' follow-up (61/65) was achieved in this study.

RESULTS

The survival rate was 75.0% (21/28) and 62.0% (44/71) among infants born at 22 and 23 weeks' gestation, respectively. Infants who died weighed less (525.5 vs. 578 g, p = 0.04) and their intrauterine growth retardation (IUGR) rate (<5th percentile) was higher (14.7 vs. 1.5%, p = 0.02). Mortality was associated with an increased incidence of bradycardia on fetal heart rate monitoring (11.8 vs. 1.5%, p = 0.046), periventricular hemorrhagic infarction (PVHI; 32.4 vs. 6.2%, p = 0.001), necrotizing enterocolitis (NEC, surgery or drain tube; 14.7 vs. 0.0%, p = 0.004), and tension pneumothorax (29.4 vs. 6.2%, p = 0.004). There were significant differences in the proportion of PVHI (15.4 vs. 0%, p = 0.03) between infants with and without NDI.

CONCLUSIONS

IUGR, bradycardia, PVHI, NEC, and tension pneumothorax were associated with neonatal mortality among infants born at 22-23 weeks' gestation. NDI at 36-42 months' chronological age was associated with PVHI.

Prophylactic efficacy of enteral antifungal administration of miconazole for intestinal perforation, especially for necrotizing enterocolitis: a historical cohort study at a single institution

PURPOSE

Despite improvements in neonatal intensive care, the outcomes of extremely-low-birth-weight infants (ELBWIs) with surgical diseases remain to be improved. We started administering enteral miconazole (MCZ) to ELBWIs from 2002 to prevent fungal infection. Since then, the incidence of intestinal perforation has significantly decreased. We investigated this prophylactic effect of MCZ against necrotizing enterocolitis (NEC) and focal intestinal perforation (FIP) and explored a new prophylactic concept against intestinal perforation.

METHODS

We designed a historical cohort study to evaluate the effect of MCZ for intestinal perforation in ELBWIs who underwent treatment in our neonatal intensive-care unit between January 1998 and December 2005. We divided these cases into two groups: the Pre-MCZ group and the Post-MCZ group. We compared the morbidity, clinical outcomes and pathological features of NEC and FIP.

RESULTS

The rate of intestinal perforation with NEC was significantly reduced after the introduction of MCZ (p = 0.007, odds ratio; 3.782, 95% confidence interval; 1.368-12.08). The pathological findings of NEC specimens showed that the accumulation of inflammatory cells was significantly reduced in the Post-MCZ group when compared with the Pre-MCZ group (p < 0.05).

CONCLUSIONS

The efficacy of the enteral administration of MCZ on intestinal perforation with NEC highlights a new prophylactic concept in the clinical management of ELBWIs.

Risk factors of meconium-related ileus in very low birth weight infants: patients-control study

Very low birth weight (VLBW) neonates experience various problems, including meconium-related ileus (MRI). This study investigated the risk factors of MRI and surgical MRI in VLBW infants. VLBW neonates admitted to the Neonatal Intensive Care Unit of Seoul National University Children's Hospital from October 2002 to September 2016 were included in the study. The diagnostic criteria for MRI were a decreased frequency of defecation with intolerable feeding, vomiting, and increased gastric residue (>50%); meconium-filled bowel dilatation in an imaging study; and no evidence of necrotizing enteritis or spontaneous intestinal perforation. Medical MRIs and surgical MRIs were managed through conventional treatment and surgical intervention. Of 1543 neonates, 69 and 1474 were in the patient and control groups, respectively. The risk factors for MRI include low birth weight (BW), cesarean section delivery, fetal distress, maternal diabetes, maternal hypertension, and maternal steroid use. Low BW and fetal distress were independent risk factors for MRI. Compared to the medical MRI group (n = 44), the risk factors for surgical MRI (n = 25) included males, younger gestational age, low BW, and meconium located at the small bowel. Male gender and low BW were independent risk factors for surgical MRI. Low BW and fetal distress were independent risk factors for MRI and male gender and low BW were independent risk factors for surgical MRI. In VLBW neonates, careful attention to the risk factors for MRI could minimize or avoid surgical interventions.

Case Report: Intact Survival of a Marginally Viable Male Infant Born Weighing 268 Grams at 24 Weeks Gestation

We report the case of a preterm small for gestational age male infant born at 24 weeks of gestation with a birth weight of 268 g who was discharged from our hospital without the requirement for home oxygen therapy or tube feeding. He did not experience severe intraventricular hemorrhage, periventricular leukomalacia, hearing disability, or any other serious complications. At that time (February 2019), according to the University of Iowa's Tiniest Babies Registry, he was the tiniest male infant in the world to survive without any serious complications other than severe retinopathy of prematurity that required laser therapy. Although the survival rate of infants with extremely low birth weight is improving worldwide, a high mortality rate and incidence of severe complications remain common for infants weighing <300 g at birth, particularly in male infants. In recent years, there have been frequent discussions regarding the ethical and social issues involved in treating extremely preterm infants weighing <400 g. Despite the challenges, reports of such infants surviving are increasing. Neonatal medicine has already achieved great success in treating infants weighing 400 g or more at birth. However, lack of evidence and experience may make physicians reluctant to treat infants weighing less than this. The present case demonstrates that intact survival of a marginally viable male infant with a birth weight of <300 g is possible with minimal handling and family involvement beginning shortly after birth. Our detailed description of the clinical course of this case should provide invaluable information to physicians around the world who treat such infants. This report will aid in the progress of neonatal medicine and help to address many of the social and ethical issues surrounding their care.

Safety and efficacy of mucous fistula refeeding in low-birth-weight infants with enterostomies

PURPOSE

To investigate the safety and efficacy of mucous fistula refeeding (MFR) in low-birth-weight infants.

METHODS

Between December 2006 and December 2018, medical records of low-birth-weight infants who underwent small bowel enterostomy formation in the neonatal period and subsequent stoma closure at our institution were retrospectively reviewed. Patients were assigned to "refeeding" (RF) and "non-refeeding" (NRF) groups, which were compared for patient characteristics and clinical outcomes. We also cultured the proximal stoma output over time in the RF group and reviewed changes in the flora to evaluate the safety of refeeding.

RESULTS

In the RF group, compared with that before refeeding, there was significantly more rapid weight gain after refeeding (17.7 vs 10.6 g/day; P = 0.002). Median total time of parenteral nutrition (PN) was 25 and 87 days in the RF and NRF groups, respectively (P = 0.001). The number of patients who developed PN-associated liver disease (PNALD) was smaller in the RF group (P = 0.12). No complications of MFR were noted and no pathogenic bacteria were cultured.

CONCLUSION

MFR was able to diminish the need for PN, which potentially decreased the incidence of PNALD, and was safe as there were no complications of the refeeding process.

Comparison of Acute Abdominal Surgical Outcomes of Extremely-Low-Birth-Weight Neonates according to Differential Diagnosis

BACKGROUND

Improvements in perinatal intensive care have improved survival of extremely-low-birth-weight (ELBW) neonates, although the risk of acute abdomen has increased. The differential diagnosis resulting in abdominal surgery can be categorized into necrotizing enterocolitis (NEC), spontaneous intestinal perforation (SIP), meconium-related ileus (MRI), and meconium non-related ileus (MNRI). The purpose of this study was to review our experience with abdominal surgery for ELBW neonates, and to evaluate characteristics and prognosis according to the differential diagnosis.

METHODS

Medical records of ELBW neonates treated between 2003 and 2015 were retrospectively reviewed.

RESULTS

Of 805 ELBW neonates, 65 (8.1%) received abdominal surgery. The numbers of cases by disease category were 29 for NEC, 18 for SIP, 13 for MRI, and 5 for MNRI. Ostoma formation was performed in 61 (93.8%) patients; primary anastomosis without ostoma was performed in 4 (6.2%). All patients without ostoma formation experienced re-perforation of the anastomosis site. Seven patients had 30-day postoperative mortality (6 had NEC). Long-term survival of the surgical and non-surgical groups was not statistically different. NEC was a poor prognostic factor for survival outcome (P = 0.033).

CONCLUSION

Abdominal surgery for ELBW neonates is feasible. Ostoma formation can lead to reduced complications compared to primary anastomosis.

Non-Cystic Fibrosis-Related Meconium Ileus: GUCY2C-Associated Disease Discovered through Rapid Neonatal Whole-Exome Sequencing

Meconium ileus is caused by cystic fibrosis; however, mutations in the GUCY2C gene also cause this disease. We report non-cystic fibrosis meconium ileus in an infant of non-Middle Eastern origin with compound heterozygous mutations in GUCY2C.

The Optimal Timing of Enterostomy Closure in Extremely Low Birth Weight Patients for Acute Abdomen

There are few reports on enterostomy closure (EC) timing for acute abdomen in extremely low birth weight (ELBW) patients. We retrospectively reviewed ELBW patients who underwent enterostomy formation (EF) and subsequent EC. We investigated baseline characteristics, surgical outcomes, and follow-up data of 55 patients and analyzed optimal timing by age at EC, enterostomy duration, and body weight (Bwt) at EC. The minimum p-value approach (MPA) using the Chi-squared test was used to determine each cut-off value. Mean gestational age was 25⁺³ weeks, while mean age and Bwt at EF were 10 days and 660 g. Enterostomy duration and Bwt at EC were 102 days and 2400 g. Fourteen surgical complications were related to EC. The MPA identified a cut-off of 2100 g (p = 0.039) at EC but no significant cut-off age or enterostomy duration. The 18 patients <2100 g had more enterostomy-related problems at EC than the >2100 g group (66.7% vs 10.8%, p < 0.001). No other characteristics were significantly different. Operation time, ventilator period, hospital stay, parenteral nutrition duration, and full feeding day were significantly longer in <2100 g patients. Follow-up Bwt did not differ (11.55 kg vs 13.95 kg, p = 0.324). Our findings suggest EC can be safely performed when Bwt is over 2100 g.

Oral diatrizoate acid for meconium-related ileus in extremely preterm infants

BACKGROUND

Intestinal disorders are common in very low-birthweight infants. The purpose of this study was to evaluate the impact of prophylactic oral Gastrografin^® (diatrizoate acid) on meconium-related ileus (MRI) in extremely preterm infants.

METHODS

This was a retrospective case-control study of infants born extremely preterm at <28 weeks of gestation and treated with diatrizoate acid (prophylactic group) or not (control group) in the periods 2007-2014 and 2000-2009, respectively. In the 2007-2014 period, 120 infants received prophylactic diatrizoate acid solution. From the 165 infants in the control group, we selected 120 infants matched for gestational age. Cases of death before 72 h of life or congenital abnormalities were excluded. Intestinal disorders, time until full enteral feeding, duration of hospital stay, mortality rate, and neurodevelopmental outcome were compared.

RESULTS

MRI occurred in six infants in the control group and in none of the infants in the prophylactic group (P = 0.039). Median time until full enteral feeding was 25 versus 22 days (P < 0.01), hospital stay was 142 versus 126 days (P < 0.01), and mortality rate for infants aged 24-27 weeks was 8.2% versus 0% (P = 0.021), respectively.

CONCLUSIONS

Prophylactic oral diatrizoate acid reduced MRI in extremely preterm infants without side-effects and decreased the mortality rate of infants born at 24-27 weeks, and is thus beneficial in extremely preterm infants.

Sutureless enterostomy for extremely low birth weight infants

OBJECTIVE

In recent years, improved survival rates of extremely low birth weight infants (ELBWIs) have led to an increasing number of enterostomy performed for those with meconium obstruction of prematurity (MOP)^1,2, spontaneous intestinal perforation (SIP)^3,4. To prevent serious stoma-related complications such as stoma side perforation, prolapse, fall and surgical site infection, we introduce our new "sutureless enterostomy" technique.

METHODS

We present the procedures in detail. We reviewed the medical records of twelve patients who underwent "sutureless enterostomy" in our neonatal intensive care unit from 2007 to 2013. Patient attributes, surgery-related items, stoma-related complications and outcomes were investigated.

RESULTS

Mean birth weight was 671±158g (mean±S.D.). Six cases of MOP, three cases of SIP and three cases of NEC were diagnosed. Mean operative time was 75±35min (mean±S.D.) None of them presented any of early stoma-related complications (necrosis, fall, and surgical site infection). However the parastomal hernia occurred in one patient as late complication. Three deaths occurred postoperatively as a result of exacerbations of their conditions.

CONCLUSIONS

Based on our preliminary observations, our new "sutureless enterostomy" was done safely and reduced the risk of stoma-related complications. It may be an ideal procedure for the ELBWI with MOP or SIP.

Timing and outcome of stoma closure in very low birth weight infants with surgical intestinal disorders

PURPOSE

Very low birth weight infants (VLBWIs) are at risk of surgical intestinal disorders including necrotizing enterocolitis (NEC), focal intestinal perforation (FIP), and meconium-related ileus (MRI). We conducted this study to verify whether the timing of stoma closure and that of enteral nutrition establishment after stoma closure in VLBWIs differ among the most common disorders.

METHODS

A retrospective multicenter study was conducted at 11 institutes. We reviewed the timing of stoma closure and enteral nutrition establishment in VLBWIs who underwent stoma creation for intestinal disorders.

RESULTS

We reviewed the medical records of 73 infants: 21 with NEC, 24 with FIP, and 25 with MRI. The postnatal age at stoma closure was 107 (28-359) days for NEC, 97 (25-302) days for FIP, and 101 (15-264) days for MRI (p = 0.793), and the postnatal age at establishment of enteral nutrition was 129 (42-381) days for NEC, 117 (41-325) days for FIP, and 128 (25-308) days for MRI (p = 0.855). The body weights at stoma closure were 1768 (620-3869) g for NEC, 1669 (1100-3040) g for FIP, and 1632 (940-3776) g (p = 0.614) for MRI. There were no significant differences among the three groups.

CONCLUSIONS

The present study revealed that the time and body weights at stoma closure and the postoperative restoration of bowel function in VLBWIs did not differ among the three diseases.

Intestinal perforation in the premature infant

OBJECTIVE

To compare demographic data, prenatal and postnatal characteristics, laboratory data, and outcomes in a cohort of premature infants with spontaneous ileal perforation (SIP), surgical necrotizing enterocolitis (sNEC) and matched controls.

METHODS

A retrospective case-control study of infants with intestinal perforation with a birth weight (BW) less than 2,000 grams and gestational age (GA) less than 34 weeks and infants without perforation matched for BW (±150 grams) and GA (±1week).

RESULTS

130 premature infants were included, 30 infants with SIP, 35 infants with sNEC and 65 control infants. The median age of onset was 5 days postnatal age in SIP versus 25 days in sNEC (p < 0.001) and the peak onset was at 26 weeks corrected GA for SIP and 30 weeks corrected GA for sNEC. Infants with perforation had significantly higher rates of mortality (p < 0.001) and common morbidities associated with prematurity. Administration of corticosteroids and indomethacin did not differ among groups. SIP was more common among infants born to young mothers (p = 0.04) and less common in infants receiving caffeine (p = 0.02). sNEC was less common among infants receiving early red cell transfusion (p = 0.01). Perforation and sNEC trended towards less common in infants receiving inhaled nitric oxide.

CONCLUSION

SIP and sNEC are distinct clinical entities. Potential protective effects of caffeine, inhaled nitric oxide, and early transfusion should be further studied.

Neonatal gastrointestinal perforation in Japan: a nationwide survey

PURPOSE

The purpose of this study is to identify the current clinical features of neonatal gastrointestinal perforation in Japan.

METHODS

A questionnaire about cases of neonatal gastrointestinal perforation treated in recent 5 years was sent to participating institutions of the Japanese Society of Pediatric Surgeons (JSPS).

RESULTS

Five hundred and thirty-six neonates with gastrointestinal perforation were treated. They consisted of 42 patients with gastric rupture/perforation (GR), 33 patients with intestinal atresia/stenosis (IA), 3 patients with malrotation (ML), 118 patients with necrotizing enterocolitis (NEC), 160 patients with focal intestinal perforation (FIP), 46 patients with meconium-related ileus (MRI), 77 patients with meconium peritonitis (MP), and 57 patients with other conditions. The total mortality rate was 20.5 %. The mortality rates of the patients with GR, IA, ML, NEC, FIP, MRI, and MP were 9.5, 9.1, 0, 33.1, 20.6, 28.2, and 9.1 %, respectively. In 263 cases involving extremely low-birth-weight neonates (ELBW), 108 died (mortality rate 41.1 %). The mortality rates for ELBW with GR, NEC, FIP, MRI, MP, and other conditions were 27.3 % (3/11), 58.5 % (48/82), 21.6 % (24/111), 70.6 % (24/34), 57.1 % (4/7), and 27.8 % (5/18), respectively.

CONCLUSIONS

The mortality rates for ELBW decreased from 62.8 % in the previous survey to 41.1 % by the time of this survey.

Risk factors and prevention for surgical intestinal disorders in extremely low birth weight infants

PURPOSE

Surgical intestinal disorders (SID), such as necrotizing enterocolitis (NEC), focal intestinal perforation (FIP), and meconium-related ileus (MRI), are serious morbidities in extremely low birth weight (ELBW, birth weight <1000 g) infants. From 2010, we performed enteral antifungal prophylaxis (EAP) in ELBWI to prevent for SID. The aim of this study was to identify disease-specific risk factors and to evaluate the efficacy of prevention for SID in ELBW infants.

METHODS

A retrospective chart review of all consecutive patients between January 2006 and March 2015, which included 323 ELBW infants who were admitted to Shizuoka Children's Hospital, was conducted.

RESULTS

The number of infants with NEC, FIP, and MRI was 9, 12, and 13, respectively; 28 in 323 ELBW infants died. The control group defined the cases were not SID. In-hospital mortality was higher in infants with NEC relative to those in the control group. On logistic regression analysis, low gestational age and cardiac malformations were associated with increased risk of NEC. IUGR were associated with increased risk of MRI. EAP decreased risk of NEC and FIP. Low gestational weight and NEC were associated with increased risk of death.

CONCLUSION

Survival to hospital discharge after operation for NEC in ELBW infants remains poor. EAP decreased risk of NEC and FIP in ELBW infants.

Risk factors for surgical intestinal disorders in VLBW infants: Case-control study

BACKGROUND

Very low-birthweight (VLBW) infants (VLBWI) are at increased risk for surgical intestinal disorders including necrotizing enterocolitis (NEC), focal intestinal perforation (FIP) and meconium-related ileus (MRI). The aim of this study was to identify disease-specific risk factors for surgical intestinal disorders in VLBWI.

METHODS

A retrospective multicenter case-control study was conducted at 11 institutes. We reviewed VLBWI who underwent laparotomy for intestinal disorders including perforation and intractable bowel obstruction. The surgical disorders were classified into four categories (NEC, FIP, MRI, others) based on the macroscopic findings at operation. In order to identify risk factors, two matched controls for each subject were chosen based on gestational age and birthweight. OR and 95%CI were calculated using a conditional logistic regression model and a multivariate model.

RESULTS

A total of 150 cases (NEC, n = 44; FIP, n = 47; MRI, n = 42; others, n = 17) and 293 controls were identified. The cases and controls were similar in terms of gestational age and birthweight (cases/controls, 26.7 ± 2.5/26.5 ± 2.6 weeks; 790 ± 256/795 ± 257 g). On multivariate modeling, disease-specific risk factors were as follows: female (OR, 0.23; 95%CI: 0.06-0.89), respiratory distress syndrome (OR, 35.7; 95%CI: 2.48-514) and patent ductus arteriosus (OR, 10.9; 95%CI: 1.51-79.3) for NEC; outborn delivery (OR, 5.47; 95%CI: 1.48-20.2) for FIP; and twin pregnancy (OR, 4.25; 95%CI: 1.06-17.1), PROM (OR, 6.85; 95%CI: 1.33-35.4) and maternal steroid (OR, 0.23; 95%CI: 0.07-0.79) for MRI.

CONCLUSIONS

Different risk factors were identified for NEC, FIP and MRI, suggesting that each disease has a different etiology, and that different strategies are required to prevent these diseases.

Reduced early dried blood spot citrulline levels in preterm infants with meconium obstruction of prematurity

BACKGROUND

Citrulline is a non-protein amino acid synthesized in the enterocytes of the small bowel. Recent studies have reported that plasma citrulline levels correlate with functional enterocyte mass.

AIMS

This study aimed to determine the normal dried blood spot (DBS) citrulline levels and to determine the existence of a correlation between citrulline levels and meconium obstruction of prematurity (MOP).

STUDY DESIGN AND SUBJECTS

A retrospective cohort study was performed involving 285 infants born at less than 32weeks gestation who were admitted to the neonatal intensive care unit between Oct 2009 and Aug 2014.

OUTCOME MEASURES

We analyzed the DBS citrulline levels, which are routinely measured via newborn screening at 7days following birth, using liquid chromatography-MS/MS. We investigated the relationship between DBS citrulline levels and clinical parameters such as gestational age (GA), body measurements at birth, gender, or the presence or absence of either necrotizing enterocolitis or MOP.

RESULTS

A total of 229 infants with a median GA of 29.6weeks and a median birth weight of 1160g were included. DBS citrulline levels were not associated with GA, body measurements at birth or gender. DBS citrulline levels were significantly decreased when patients presented with MOP (p=0.037).

CONCLUSIONS

Early DBS citrulline levels were not associated with either GA or body measurements at birth but were reduced among preterm infants with MOP compared with the control infants. These results may be indicative of abnormal fetal intestinal development and reduced functional enterocyte mass among preterm infants with MOP.

Meconium-related ileus in very low birth weight and extremely low birth weight infants: immediate and one-year postoperative outcomes

PURPOSE

One of the major causes of bowel obstruction in extremely premature infants is a meconium obstruction. However, there are many challenges not only in the recognition and diagnosis, but also in the management of meconium obstruction. This study aimed to find perioperative clinical features and determine the postoperative course of meconium-related ileus in very low birth weight (VLBW) and extremely low birth weight (ELBW) infants.

METHODS

We retrospectively reviewed the clinical data of premature infants (n = 11, VLBW infnats; n = 16, ELBW infants) with a meconium-related ileus who underwent operation for intractable ileus between January 2009 and May 2013.

RESULTS

The average duration of conservative management was longer and postnatal age was older in ELBW infants than VLBW infants: 19.9 days vs. 11.5 days and 34.9 days vs. 19.2 days. The immediate postoperative course (day that beginning feeding and full feeding) was not significantly different based on birth weight, but the ELBW infants had slightly higher mortality. At 12 months of corrected age after operation, both average body weight and average height was below 10th percentile for growth in most infants (61.1%).

CONCLUSION

There was a slightly high mortality in the ELBW infants, but two groups did not experience significant differences in the immediate postoperative course of meconium-related ileus. Nevertheless, considering their growth patterns, it is necessary to do a close follow-up and more aggressive nutritional management to achieve optimal growth and development in both patient groups.

Parenteral nutrition-associated liver disease in extremely low-birthweight infants with intestinal disease

BACKGROUND

The aim of this study was to investigate factors associated with the development of parenteral nutrition-associated liver disease (PNALD) and to examine the clinicopathological relationship of PNALD in extremely low-birthweight infants (ELBWI).

METHODS

The subjects were 13 ELBWI who had received PN because of intestinal perforation or functional ileus between 2000 and 2013. We measured the serum levels of biochemical parameters, including aspartate aminotransferase, alanine aminotransferase, and direct bilirubin. Liver histopathology was examined in relation to outcome. The subjects were categorized into two groups on liver histopathology: F(+), development of hepatic fibrosis and necrosis with/without cholestasis; and F(-), no hepatic fibrosis.

RESULTS

Of 13 ELBWI, five died of hepatic failure, five died of sepsis, and the other three were alive at the time of the study. Of the five infants who died of hepatic failure, two developed fulminant hepatitis without cholestasis, and the other three developed chronic cholestasis and finally hepatic failure. Postmortem histopathology in F(+) indicated not only massive hepatic necrosis, but also massive hepatic fibrosis. These histopathological findings explained the clinical presentation of portal hypertension. There were significant differences in the fasting period after intestinal disease onset between the two groups.

CONCLUSION

The prolonged fasting with PN is responsible for severe hepatocellular necrosis with fibrosis and consequent lethal portal hypertension.

Outcome in VLBW infants with surgical intestinal disorder at 18 months of corrected age

BACKGROUND

Surgical intestinal disorders, such as necrotizing enterocolitis (NEC), focal intestinal perforation (FIP), and meconium-related ileus (MRI), are serious morbidities in very low-birthweight infants (VLBWI). The aim of this study was to compare the composite outcomes of death or neurodevelopmental impairment (NDI) in VLBWI with surgical intestinal disorders and assess independent risk factors for death and NDI at 18 months of corrected age.

METHODS

A retrospective matched-cohort study was conducted at 11 institutes. We included VLBWI who had undergone laparotomy for NEC, FIP, and MRI. Two control subjects were chosen for every surgical patient and matched for gestational age and birthweight to form the comparison group. Death and neurodevelopmental outcome at 18 months of corrected age were evaluated.

RESULTS

The number of infants in the NEC, FIP, MRI, and control groups was 44, 47, 42, and 261, respectively. In-hospital mortality was higher in infants with NEC and MRI relative to those in the control group (P < 0.001). The incidence rate for NDI at 18 months of corrected age was higher in infants with MRI relative to those in the control group (P = 0.021). On logistic regression analysis, low gestational age, male sex, small for gestational age, intraventricular hemorrhage, and MRI were associated with increased risk of death or NDI at 18 months of corrected age.

CONCLUSIONS

NEC and MRI were associated with in-hospital mortality, and MRI was associated with NDI or death at 18 months of corrected age.

Ultrasound-guided contrast enema for meconium obstruction in very low birth weight infants: Factors that affect treatment success

INTRODUCTION

This study aimed to assess the therapeutic results of ultrasound (US)-guided water-soluble contrast enema in very low birth weight (VLBW) preterm infants (<1,500 g) with meconium obstruction and to study factors that affect therapeutic results.

METHODS

This study included a total of 33 consecutive VLBW infants with clinically diagnosed meconium obstruction underwent US-guided water-soluble contrast enema, from April 2007 to March 2014. Patients were classified into two groups based on to procedure outcome: the success group (evacuation of the meconium plug resolution followed by improved bowel distention within 2 days of the procedure, without additional interventions), and the failure group (the contrast enema failed to relieve the obstruction, or other procedure-related complications occurred). Patient- and mother-related clinical factors and procedure-related factors were compared between both groups.

RESULTS

Overall success rate was 54.5%, with 18 successful (M:F=10:8), and 15 failure (M:F=7:8) cases. When compared with the failure group, the success group patients showed statistically significant older gestational age (29(+1) vs. 27 weeks; p=0.028), larger birth weight (1023.1g vs. 790.3g; p=0.048), and higher body weight on the day of the procedure (1036.2g vs. 801.6g, p=0.049). However, no statistically significant differences were seen between other patient and maternal factors. Among the procedure-related factors, retrial of contrast injection during the procedure was associated with significantly higher success than the single trial (p=0.027). The presence of refluxed contrast into the distal ileum was the statistically significant predictor for success of the procedure (p=0.038). There were three cases of bowel perforation (9.1% per person).

CONCLUSION

US-guided water-soluble contrast enema in VLBW infants with meconium obstruction showed a 54.5% success rate and a 9.1% perforation rate per person. Among the procedure-related factors, retrial of contrast injection during the procedure and the presence of refluxed contrast into the distal ileum were related to the success of the procedure.

Parenteral-nutrition-associated liver disease after intestinal perforation in extremely low-birthweight infants: consequent lethal portal hypertension

BACKGROUND

Parenteral nutrition (PN)-associated liver dysfunction (PNALD) in term infants usually manifests as intrahepatic cholestasis, which recovers with enteral nutrition (EN) in most cases; however, as the number of extremely low-birthweight infants (ELBWI) has been increasing, and consequently intestinal diseases associated with ELBWI have been increasing, more intractable PNALD has been encountered after surgical treatment in ELBWI, which does not resolve or rather worsens with EN.

METHODS

Three cases of ELBWI with intestinal perforation, which developed PNALD and eventually died of hepatic failure with intractable portal hypertension, were reviewed. Their gestational age and birthweight ranged from 23 to 26 weeks, and from 434 to 968 g, respectively. The intestinal diseases included necrotizing enteritis in two and meconium-related ileus with focal intestinal perforation in one.

RESULTS

The duration of total PN without EN in the three cases was 17, 24 and 24 days, respectively. The interval between the introduction of PN and the onset of PNALD was 14, 4 and 18 days, respectively. A marked elevation of serum endotoxin level was detected in both cases of necrotizing enteritis. Histopathological study of the liver revealed marked cholestasis, significant hepatic necrosis with fibrosis, and proliferation of ductules in all these cases, which was responsible for portal hypertension.

CONCLUSIONS

PN after gastrointestinal disorders in ELBWI may cause refractory PNALD, which does not resolve, or rather worsens with the resumption of EN. Portal hypertension secondary to hepatic necrosis may be responsible for the exacerbation with the resumption of EN.