Small Bowel Dilatation Predicts Prolonged Parenteral Nutrition and Decreased Survival in Pediatric Short Bowel Syndrome

Major surgical conditions of childhood and their lifelong implications: comprehensive review

BACKGROUND

In recent decades, the survival of children with congenital anomalies and paediatric cancer has improved dramatically such that there has been a steady shift towards understanding their lifelong health outcomes. Paediatric surgeons will actively manage such conditions in childhood and adolescence, however, adult surgeons must later care for these 'grown-ups' in adulthood. This article aims to highlight some of those rare disorders encountered by paediatric surgeons requiring long-term follow-up, their management in childhood and their survivorship impact, in order that the adult specialist may be better equipped with skills and knowledge to manage these patients into adulthood.

METHODS

A comprehensive literature review was performed to identify relevant publications. Research studies, review articles and guidelines were sought, focusing on the paediatric management and long-term outcomes of surgical conditions of childhood. The article has been written for adult surgeon readership.

RESULTS

This article describes the aforementioned conditions, their management in childhood and their lifelong implications, including: oesophageal atresia, tracheo-oesophageal fistula, malrotation, short bowel syndrome, duodenal atresia, gastroschisis, exomphalos, choledochal malformations, biliary atresia, Hirschsprung disease, anorectal malformations, congenital diaphragmatic hernia, congenital lung lesions and paediatric cancer.

CONCLUSION

The increasing survivorship of children affected by surgical conditions will translate into a growing population of adults with lifelong conditions and specialist healthcare needs. The importance of transition from childhood to adulthood is becoming realized. It is hoped that this timely review will enthuse the readership to offer care for such vulnerable patients, and to collaborate with paediatric surgeons in providing successful and seamless transitional care.

Cutoffs and Characteristics of Abnormal Bowel Dilatation in Pediatric Short Bowel Syndrome

OBJECTIVES

Although excessive intestinal dilatation associates with worsened outcomes in pediatric short bowel syndrome (SBS), little is known about the natural history and definition of pathological dilatation. We addressed fore-, mid-, and hind-gut dilatation in children with SBS, who had not undergone autologous intestinal reconstructive (AIR) surgery, in relation to controls.

METHODS

SBS children without history of AIR surgery (n = 59) and age-matched controls without any disclosed intestinal pathology (n = 140) were included. Maximum diameter of duodenum, small bowel (SB), and colon were measured in each intestinal contrast series during 2002 to 2020 and expressed as diameter ratio (DR) to L5 vertebrae height. Predictive ability of DR for weaning off parenteral nutrition (PN) was analyzed with Cox proportional hazards regression models using multiple cutoffs.

RESULTS

Duodenum (DDR), SB (SBDR), and colon (CDR) DR were 53%, 183%, and 23% higher in SBS patients compared to controls ( P < 0.01 for all). The maximal DDR and SBDR measured during follow-up is associated with current PN dependence and young age. DDR correlated with SBDR ( r = 0.586, P < 0.01). Patients with maximal DDR less than 1.5, which was also the 99th percentile for controls, were 2.5-fold more likely to wean off PN ( P = 0.005), whereas SBDR and CDR were not predictive for PN duration.

CONCLUSIONS

All segments of remaining bowel, especially SB, dilate above normal levels in children with SBS. In SBS children without AIR surgery, PN dependence and young age is associated with duodenal and small intestinal dilatation, while duodenal dilatation also predicted prolonged PN.

Nutrition and Intestinal Rehabilitation of Children With Short Bowel Syndrome: A Position Paper of the ESPGHAN Committee on Nutrition. Part 2: Long-Term Follow-Up on Home Parenteral Nutrition

Short bowel syndrome (SBS) is the leading cause of intestinal failure (IF) in children. The preferred treatment for IF is parenteral nutrition which may be required until adulthood. The aim of this position paper is to review the available evidence on managing SBS and to provide practical guidance to clinicians dealing with this condition. All members of the Nutrition Committee of the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) contributed to this position paper. Some renowned experts in the field joined the team to guide with their expertise. A systematic literature search was performed from 2005 to May 2021 using PubMed, MEDLINE, and Cochrane Database of Systematic Reviews. In the absence of evidence, recommendations reflect the expert opinion of the authors. Literature on SBS mainly consists of retrospective single-center experience, thus most of the current papers and recommendations are based on expert opinion. All recommendations were voted on by the expert panel and reached >90% agreement. This second part of the position paper is dedicated to the long-term management of children with SBS-IF. The paper mainly focuses on how to achieve intestinal rehabilitation, treatment of complications, and on possible surgical and medical management to increase intestinal absorption.

Autologous Intestinal Reconstruction Surgery in Short Bowel Syndrome: Which, When, and Why

Short bowel syndrome (SBS), secondary to any natural loss or after any extensive bowel resection for congenital malformations or acquired disease, is the most common cause of intestinal failure in children. Extensive introduction of parenteral nutrition (PN) has dramatically changed the outcome of these patients, allowing for long-term survival. The main goal in children with SBS remains to be increasing enteral tolerance and weaning from PN support. Post resection intestinal adaptation allows for achievement of enteral autonomy in a subset of these patients, but the inability to progress in enteral tolerance exposes others to long-term complications of PN. Autologous intestinal reconstruction surgery (AIRS) can facilitate the fulfilment of enteral autonomy, maximizing the absorptive potential of the remaining gut. All the different intestinal reconstruction techniques, from simple procedures like tapering, reversed segments, and colon interposition, to more complex lengthening procedures (LILT: longitudinal intestinal lengthening and tailoring, STEP: serial transverse enteroplasty, and SILT: spiral intestinal lengthening and tailoring) and techniques designed for peculiar problems like controlled intestinal tissue expansion or duodenal lengthening are presented. AIRS indications, clinical applications, and results reported in the literature are reviewed.

Infection Prevention and Management in Pediatric Short Bowel Syndrome

Short bowel syndrome (SBS) is a rare disease with potentially life-threatening consequences. In addition to intestinal failure-associated liver disease, infections and other complications related to central venous catheters (CVCs) cause a significant burden to patients with SBS and may even necessitate an intestinal transplant eventually. The need for long-term central venous access and the intestinal dysfunction associated with SBS drive the need for intestinal failure-specific approach to prevent and treat infections in patients with SBS. In bacterial infections, the line can often be salvaged with proficient antibiotic therapy. Repeated catheter replacements are predisposed to recurrent infections and thrombotic complications, which may limit the long-term survival of patients with SBS. Protocol-based CVC access procedures and daily care including taurolidine and ethanol catheter locks have been shown to reduce infection rates substantially. Compromised intestinal function in SBS predisposes to small bowel bacterial overgrowth, mucosal injury, and increased permeability. These pathophysiological changes are concentrated in a subset of patients with excessive bowel dilatation and frequent bowel-derived infections. In such patients, reconstructive intestinal surgery may be indicated. Probiotics have not been effective in infection prevention in SBS and carry a significant risk of complications. While more studies focusing on the prevention of infections and their complications are needed, protocol-based approach and multidisciplinary teams in the care of patients with SBS have been shown to reduce complications and improve outcomes.

Compromised duodenal mucosal integrity in children with short bowel syndrome after adaptation to enteral autonomy

BACKGROUND

Intestinal adaptation has been extensively studied experimentally, but very limited data is available on human subjects. In this study we assessed intestinal adaption in humans with short bowel syndrome (SBS).

METHODS

We comparatively evaluated mucosal hyperplasia, inflammation, barrier function and nutrient transport using histology, immunohistochemistry and qPCR for selected 52 key genes in duodenal biopsies obtained from children with SBS after weaning off parenteral nutrition (n = 33), and matched controls without intestinal pathology (n = 12). Small bowel dilatation was assessed from contrast small bowel series.

RESULTS

Duodenal mucosa of SBS children showed increased histologic inflammation of lamina propria (p = 0.033) and mucosal mRNA expression of tumor necrosis factor (p = 0.027), transforming growth factor (TGF)-β2 (p = 0.006) and caveolin-1 (CAV1; p = 0.001). Villus height, crypt depth, enterocyte proliferation, apoptosis and expression of proliferation and nutrient transport genes remained unchanged. Pathologic small bowel dilatation reduced crypt depth (p = 0.045) and downregulated mRNA expression of interleukin (IL)-6 by three-fold (p = 0.008), while correlating negatively with IL6 (r = -0.609, p = 0.004). Loss of ileocecal valve (ICV) upregulated mRNA expression of toll-like receptor 4 (TLR4), TGF-β1, CAV1, several apoptosis regulating genes, and mRNA expression of zonulin (p < 0.05 for all).

CONCLUSIONS

Despite successful adaptation to enteral autonomy, duodenal mucosa of SBS children displayed histologic and molecular signs of abnormal inflammation and regulation of epithelial permeability, whereas no structural or molecular signs of adaptive hyperplasia or enhanced nutrient transport were observed. Excessive dilatation of the remaining small bowel paralleled impaired duodenal crypt homeostasis, while absence of ICV modified regulation of mucosal inflammation, regeneration and permeability.

LEVEL OF EVIDENCE

II.

To Wean or Not to Wean: The Role of Autologous Reconstructive Surgery in the Natural History of Pediatric Short Bowel Syndrome on Behalf of Italian Society for Gastroenterology, Hepatology and Nutrition (SIGENP)

Pediatric Short Bowel Syndrome (SBS) can require prolonged parenteral nutrition (PN). Over the years, SBS management has been implemented by autologous gastrointestinal reconstructive surgery (AGIR). The primary objective of the present review was to assess the effect of AGIR on weaning off PN. We also evaluated how AGIR impacts survival, the need for transplantation (Tx) and the development of liver disease (LD). We conducted a systematic literature search to identify studies published from January 1999 to the present and 947 patients were identified. PN alone was weakly associated with higher probability of weaning from PN (OR = 1.1, p = 0.03) and of surviving (OR = 1.05, p = 0.01). Adjusting for age, the probability of weaning off PN but of not surviving remained significantly associated with PN alone (OR = 1.08, p = 0.03). Finally, adjusting for age and primary diagnosis (gastroschisis), any association was lost. The prevalence of TX and LD did not differ by groups. In conclusion, in view of the low benefit in terms of intestinal adaptation and of the not negligible rate of complications (20%), a careful selection of candidates for AGIR should be required. Bowel dilation associated with failure of advancing EN and poor growth, should be criteria to refer for AGIR.

New Insights Into Intestinal Failure-Associated Liver Disease in Children

Development of intestinal failure-associated liver disease (IFALD) is a common complication of long-term parenteral nutrition (PN) in children and adults. The molecular and cellular mechanisms and the phases of IFALD are now being delineated. Components of PN lipid emulsions, including plant sterols, interact with hepatic innate immune activation promoted by products of gut bacterial overgrowth/dysbiosis and altered intestinal barrier function (gut-liver axis) and by episodes of sepsis to cause cholestasis and IFALD. New therapeutic strategies, including modifications of intravenous lipid emulsions to reduce pro-inflammatory fatty acids and plant sterol content, can lower the risk of IFALD, reverse cholestasis, and reduce complications, although the significance of persisting hepatic fibrosis is unknown. This review will provide an update on advances in the pathogenesis of IFALD, newer therapeutic and preventative strategies, and challenges that confront managing patients with IFALD.

Nontransplant Surgery for Intestinal Failure

Insufficient absorptive mucosal surface is the fundamental problem in the short bowel state. Intestinal adaptation has been well studied, and it is well recognized that it may lead to dilatation of the bowel with increased thickness of the bowel wall, resulting from both mucosal hypertrophy and hyperplasia. Autologous reconstructive surgery exploits bowel dilatation in short bowel syndrome and maximizes the absorptive potential of the available mucosal surface. Indeed, autologous gastrointestinal reconstructive procedures may be better viewed as optimizing bowel diameter rather than focusing on length, thus allowing better prograde peristalsis and improved contact between luminal nutrients and mucosa, ultimately enhancing absorption.

Short Bowel Syndrome as the Leading Cause of Intestinal Failure in Early Life: Some Insights into the Management

Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.

Short bowel mucosal morphology, proliferation and inflammation at first and repeat STEP procedures

BACKGROUND

Although serial transverse enteroplasty (STEP) improves function of dilated short bowel, a significant proportion of patients require repeat surgery. To address underlying reasons for unsuccessful STEP, we compared small intestinal mucosal characteristics between initial and repeat STEP procedures in children with short bowel syndrome (SBS).

METHODS

Fifteen SBS children, who underwent 13 first and 7 repeat STEP procedures with full thickness small bowel samples at median age 1.5 years (IQR 0.7-3.7) were included. The specimens were analyzed histologically for mucosal morphology, inflammation and muscular thickness. Mucosal proliferation and apoptosis was analyzed with MIB1 and Tunel immunohistochemistry.

RESULTS

Median small bowel length increased 42% by initial STEP and 13% by repeat STEP (p=0.05), while enteral caloric intake increased from 6% to 36% (p=0.07) during 14 (12-42) months between the procedures. Abnormal mucosal inflammation was frequently observed both at initial (69%) and additional STEP (86%, p=0.52) surgery. Villus height, crypt depth, enterocyte proliferation and apoptosis as well as muscular thickness were comparable at first and repeat STEP (p>0.05 for all). Patients, who required repeat STEP tended to be younger (p=0.057) with less apoptotic crypt cells (p=0.031) at first STEP. Absence of ileocecal valve associated with increased intraepithelial leukocyte count and reduced crypt cell proliferation index (p<0.05 for both).

CONCLUSIONS

No adaptive mucosal hyperplasia or muscular alterations occurred between first and repeat STEP. Persistent inflammation and lacking mucosal growth may contribute to continuing bowel dysfunction in SBS children, who require repeat STEP procedure, especially after removal of the ileocecal valve.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Short bowel syndrome in children and adults: from rehabilitation to transplantation

Short bowel syndrome (SBS) is a dramatic clinical condition in both children and adults; the residual bowel length is not sufficient to avoid intestinal failure, with subsequent malnutrition and growth retardation, and intravenous support is required to provide the nutrients normally coming from the intestine. Apart from the primary disease, the medical status can be worsened by complications of intestinal failure: if there are irreversible, the prognosis is poor unless a successful intestinal rehabilitation is achieved. Areas covered: The rescue of the remnant small bowel requires a multidisciplinary expertise to achieve digestive autonomy. The use of intestinal trophic factors has shown encouraging results in improving the intestinal adaptation process. Whenever the residual bowel length is inadequate, in a well-selected population weaning parenteral nutrition (PN) off could be attempted by surgery through lengthening procedures. A further subset of patients, with total and irreversible intestinal failure and severe complications on PN, may have an indication to intestinal transplantation. This procedure is still affected by poor long-term results. Expert commentary: Novel approaches developed through a multidisciplinary team work, such as manipulation of microbiota or tissue bioengineering, should be added to current therapies to treat successfully SBS.

Three-dimensional CT enterography versus barium follow-through examination in measurement of remnant small intestinal length in short bowel syndrome patients

PURPOSE

To evaluate the feasibility and accuracy of remnant small intestinal length measured by barium follow-through (BaFT) examination and three-dimensional CT enterography (CTe).

MATERIALS AND METHODS

Twenty-nine consecutive short bowel syndrome patients (SBS) who underwent BaFT, CTe, and prior surgical measurements of small intestine were included. Measurements of total remnant small intestinal length on BaFT and CTe were compared to surgical measurements using Spearman's rank correlation coefficients, Bland-Altman plots, and paired t test.

RESULTS

The average remnant intestinal length was 73.1 ± 37.2 cm according to surgical measurement. There was a significant positive correlation between CTe and surgical measurement (r² = 0.99; p < 0.0001), and a relatively weaker correlation between BaFT and surgical measurement (r² = 0.71; p < 0.001). Compared with surgical measurement, the percentage differences of CTe and BaFT were 5.71 ± 6.71% and 27.14 ± 18.41% (mean ± SD), respectively. Furthermore, Bland-Altman plots showed good agreement between CTe and surgical measurement, whereas relatively poor agreement between BaFT and surgical measurement. However, significant difference was found among the three measurement methods by paired t test (p < 0.0001).

CONCLUSIONS

Assessment of remnant small intestinal length by CTe is accurate and acceptable for clinical application, whereas BaFT is less accurate although BaFT is more convenient and cheaper for clinical application. And CTe can provide a cost-effective and noninvasive determination of remnant small intestinal length in planning surgical and nutritional intervention in SBS patients.

Plasma Phytosterol Half-Life and Levels Are Increased in Very Low Birth Weight Preterm Infants with Parenteral Nutrition-Associated Cholestasis

Parenteral nutrition-associated cholestasis (PNAC) has been linked to plasma accumulation of phytosterols in infants receiving vegetable-oil-based lipid emulsions (LE). To date, information on the ability of infants with PNAC to metabolize intravenous (IV) phytosterols has been very limited. We characterized plasma phytosterol half-life in very low birth weight (VLBW) preterm infants with PNAC. As part of a prospective cohort study, VLBW infants with PNAC underwent serial blood sample measurements of sitosterol (Sito), campesterol (Camp), and stigmasterol (Stigma). Infants without PNAC served as controls (CTRL, control infants). Thirty-seven PNAC infants and 14 CTRL were studied. On PN day 7 and PN day 14, PNAC infants had higher plasma phytosterol concentrations compared to those of CTRL (p < 0.05). A significant and positive correlation was found between plasma Camp, Stigma, Sito concentrations, and IV phytosterol intake from birth to PN day 7 (p = 0.001, p = 0.001, and p = 0.005, respectively). Stigma concentration was positively correlated with conjugated bilirubin on PN day 7 (p = 0.012). After stopping IV LE, half-lives of Camp, Stigma, and Sito became significantly longer in PNAC infants than in CTRL (Camp: 18.8 ±6.2 vs 11.8 ±3.0 days, p = 0.001; Stigma: 13.8 ±5.8 vs 9.4 ±3.4 days, p = 0.023; Sito: 15.3 ±5.0 vs 9.8 ±3.0 days, p = 0.002). In conclusion, phytosterols increased earlier during PN and were eliminated slowly after stopping IV LE in PNAC infants than in CTRL. The Stigma concentration on PN day 7 could represent an early marker of cholestasis. Our results provide additional evidence on the relationship between IV phytosterols and PNAC.

Transverse flap duodenoplasty (TFD): a new technique in autologous bowel reconstructive surgery

BACKGROUND

Bowel dilatation is a common adaptive mechanism after intestinal resection. The symptomatic dilated dysmotile duodenum is difficult to manage, since conventional bowel tailoring and lengthening techniques are potentially hazardous because of the anatomy of the duodenal blood supply, the proximity to the pancreas, and the risk of injury to the common bile duct.

METHODS

A 2-month-old child with short bowel and a symptomatic massively dilated duodenum was treated with a Transverse Flap Duodenoplasty (TFD). The duodenum was opened longitudinally along its antimesenteric border preserving an intact strip of tissue overlying the pancreatic head. Three full thickness vascularized pedicle flaps were cut on both the anterior and posterior walls and were spirally rotated and sutured to create a uniform propulsive duodenum without diverticulae.

RESULTS

Healing was complicated by a soft anastomotic duodeno-ileal stenosis that resolved after three elective balloon dilatations. Oral feeding established rapidly. The child is growing, does not vomit, and passes 1-2 semiformed motions daily.

CONCLUSIONS

TFD is a safe and versatile technique that preserves all duodenal absorptive mucosa and that removes any risk to the pancreas, bile duct, and ampulla of Vater. Our experience, although limited, has been encouraging and leads us to suggest TFD for the management of the difficult symptomatic dysmotile dilated duodenum.

Risk factors and outcomes of tapering surgery for small intestinal dilatation in pediatric short bowel syndrome

BACKGROUND

In remains unclear why in some short bowel syndrome (SBS) patients, the remaining small bowel (SB) dilates excessively leading to requirement of tapering surgery.

METHODS

Among SBS children, we retrospectively analyzed risk factors for tapering surgery with logistic regression and compared the outcome of operated patients (n=16) to those managed conservatively (n=44) with Cox proportional hazards regression.

RESULTS

SBS was caused by necrotizing enterocolitis (NEC) (n=31), SB atresia (SBA) (n=13), midgut volvulus (n=12), or gastroschisis (n=4). Patients with spontaneous symptomatic SB dilatation unable to wean parenteral nutrition (PN) underwent tapering surgery at median age of 1.04 (interquartile range 0.70-3.27) years. Missing ICV was related to an 8-fold (p=0.003) increased risk while SBA diagnosis was related to a 13-fold risk of tapering surgery (p<0.001). Increasing SB length and NEC diagnosis were protective of tapering (p=0.027-0.004). Of operated patients, 75% reached enteral autonomy during follow-up and their postoperative adjusted PN weaning rate was similar to nonoperated children (p=0.842).

CONCLUSION

SBS children with short remaining SB, missing ICV, and SBA etiology are more likely while NEC patients are less likely than others to necessitate tapering surgery. Postoperative PN weaning rates were comparable to patients who initially had more favorable intestinal anatomy and adapted without surgery.

Surgical strategies in short bowel syndrome

Extensive loss of small bowel in all age groups has significant morbidity and mortality consequences. Despite the astonishing ability of the small bowel to compensate for an extensive loss, long-term parenteral nutrition and enteral nutrition, tailored to the need of the patients in relation to the missing intestinal regions is needed. Organ-preserving surgical intervention becomes necessary in patients with a very short intestinal transit time and in an other group of patients with impaired propulsive peristalsis. Intestinal transplantation is indicated in recurrent septical infections or if nearly all of the small bowel is missing. This review discusses indications and risks of the organ-preserving surgical therapies in children with short bowel syndrome.