Influence of bacterial overgrowth and intestinal inflammation on duration of parenteral nutrition in children with short bowel syndrome

Prevalence of small intestinal bacterial overgrowth in intestinal failure syndrome: A systematic review and meta-analysis

BACKGROUND AND AIM

Patients with intestinal failure (IF) have abnormal intestinal anatomy, secretion, and dysmotility, which impairs intestinal homeostatic mechanisms and may lead to small intestinal bacterial overgrowth (SIBO). We conducted a systematic review and meta-analysis to determine the prevalence of SIBO in patients with IF and to identify risk factors for SIBO.

METHODS

MEDLINE (PubMed) and Embase electronic databases were searched from inception to December 2023 for studies that reported the prevalence of SIBO in IF. The prevalence rates, odds ratio (OR), and 95% confidence intervals of SIBO in IF and the risk factors for SIBO in IF were calculated using random effects model.

RESULTS

Final dataset included nine studies reporting on 407 patients with IF. The prevalence of SIBO in IF was 57.5% (95% CI 44.6-69.4), with substantial heterogeneity in this analysis (I2 = 80.9, P = 0.0001). SIBO prevalence was sixfold higher in patients with IF who received parenteral nutrition (PN) compared with IF patients not on PN (OR = 6.0, 95% CI 3.0-11.9, P = 0.0001). Overall, the prevalence of SIBO in patients with IF using PPI/acid-suppressing agents (72.0%, 95% CI 57.5-83.8) was numerically higher compared with IF patients not using these agents (47.6%, 95% CI 25.7-70.2).

CONCLUSIONS

This systematic review and meta-analysis suggests that there is an increased risk of SIBO in patients with IF and that PN, and potentially, the use of PPI/acid-suppressing agents is risk factors for SIBO development in patients with IF. However, the quality of evidence is low and can be attributed to lack of case-control studies and clinical heterogeneity seen in the studies.

Small and large bowel anatomy is associated with enteral autonomy in infants with short bowel syndrome: A retrospective cohort study

BACKGROUND

Achievement of enteral autonomy (EA) is the ultimate treatment goal in pediatric intestinal failure (IF). We aimed to assess predictors of EA in pediatric short bowel syndrome (SBS) and explore the impact of residual small bowel (SB) and large bowel (LB) length on EA.

METHODS

A retrospective cohort study was performed on infants aged <12 months (n = 367, six centers) with SBS referred between 2010 and 2015. The cohort was stratified based on the achievement of EA. Statistical testing was completed using t-test, chi-square, Cox proportional hazards regression model, and Kaplan-Meier analysis.

RESULTS

EA was achieved in 229 patients. In the multivariable analysis, the percentage of residual LB (hazard ratio [HR] = 1.02; 95% CI = 1.01-1.02) and SB (HR = 1.01; 95% CI = 1.01-1.02) length, presence of the ileocecal valve (HR = 2.02; 95% CI=1.41-2.88), and not coming from a high-volume transplantation center (HR = 2.42; 95% CI = 1.68-3.49) were positively associated with EA, whereas a negative association was seen with the presence of stoma at the time when shortest remnant was documented (HR = 0.72; 95% CI = 0.52-1.00). EA achievement was significantly different between the anatomical subgroups (log-rank test P < 0.001) with an EA rate of 80.4% in infants with ≥50% SB and LB (median time 209 days); 62.5% with ≥50% SB and <50% LB (397 days); 58.3% with <50% SB and ≥50% LB (1192 days), and 25.9% with <50% SB and LB. Necrotizing enterocolitis (NEC) was not associated with a better achievement of EA (NEC vs other etiologies: log-rank test P = 0.33).

CONCLUSIONS

Overall, 62% of infants with IF secondary to SBS achieved EA over a mean time of follow-up of 2.3 years. A colon length of >50% can compensate for the loss of small bowel (<50%) and account for similar EA rates as those in children with residual SB > 50%.

ESPEN guideline on chronic intestinal failure in adults - Update 2023

BACKGROUND & AIMS

In 2016, ESPEN published the guideline for Chronic Intestinal Failure (CIF) in adults. An updated version of ESPEN guidelines on CIF due to benign disease in adults was devised in order to incorporate new evidence since the publication of the previous ESPEN guidelines.

METHODS

The grading system of the Scottish Intercollegiate Guidelines Network (SIGN) was used to grade the literature. Recommendations were graded according to the levels of evidence available as A (strong), B (conditional), 0 (weak) and Good practice points (GPP). The recommendations of the 2016 guideline (graded using the GRADE system) which were still valid, because no studies supporting an update were retrieved, were reworded and re-graded accordingly.

RESULTS

The recommendations of the 2016 guideline were reviewed, particularly focusing on definitions, and new chapters were included to devise recommendations on IF centers, chronic enterocutaneous fistulas, costs of IF, caring for CIF patients during pregnancy, transition of patients from pediatric to adult centers. The new guideline consist of 149 recommendations and 16 statements which were voted for consensus by ESPEN members, online in July 2022 and at conference during the annual Congress in September 2022. The Grade of recommendation is GPP for 96 (64.4%) of the recommendations, 0 for 29 (19.5%), B for 19 (12.7%), and A for only five (3.4%). The grade of consensus is "strong consensus" for 148 (99.3%) and "consensus" for one (0.7%) recommendation. The grade of consensus for the statements is "strong consensus" for 14 (87.5%) and "consensus" for two (12.5%).

CONCLUSIONS

It is confirmed that CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for the underlying gastrointestinal disease and to provide HPN support. Most of the recommendations were graded as GPP, but almost all received a strong consensus.

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.

Importance of Ileum and Colon in Children with Short Bowel Syndrome

BACKGROUND

It is well known that small bowel length is a dominant prognostic indicator in patients with short bowel syndrome (SBS). The relative importance of jejunum, ileum, and colon is less well defined in children with SBS. Here we review the outcome of children with SBS with respect to the type of remnant intestine.

METHODS

A retrospective review of 51 children with SBS was conducted at a single institution. The duration of parenteral nutrition use was the main outcome variable. The length of the remaining intestine as well as the type of intestine were recorded for each patient. Kaplan-Meier analyses were conducted to compare the subgroups.

RESULTS

Children with greater than 10% expected small bowel length or more than 30 cm of small bowel achieved enteral autonomy faster than those with less. The presence of ileocecal valve enhanced the ability to wean from parenteral nutrition. The presence of ileum significantly enhanced the ability to wean from parenteral nutrition. Patients with the entire colon also achieved enteral autonomy sooner than those with partial colon.

CONCLUSIONS

The preservation of ileum and colon is important in patients with SBS. Approaches to preserve or lengthen ileum and colon may be beneficial for these patients.

LEVEL OF EVIDENCE

IV.

Antibiotic Therapy for Culture-Proven Bacterial Overgrowth in Children With Intestinal Failure Results in Improved Symptoms and Growth

OBJECTIVES

To evaluate symptoms, enteral tolerance, growth, and antibiotic regimens in pediatric intestinal failure (IF) patients after treated with antibiotic therapy for small bowel bacterial overgrowth (SBBO).

METHODS

Single-center retrospective review of children 0-18 years with IF with endoscopic cultures demonstrating >10 5 CFU/mL from 2010 to 2017. Symptoms, enteral tolerance, growth, and antibiotic regimens were evaluated at the time of endoscopy and 6 months later.

RESULTS

Of 505 patients followed in our intestinal rehabilitation program, 104 underwent upper gastrointestinal endoscopy and 78 had positive duodenal cultures. Clinical data pre- and post-endoscopy were available for 56 patients. Compared to baseline, in the 6 months following targeted antibiotic treatment, children showed significant improvement in emesis or feeding intolerance (58.9% vs 23.2%, P < 0.001), abdominal pain (16.1% vs 7.1%, P = 0.02), high stool output (42.9% vs 19.6%, P = 0.002), and gross GI bleeding (19.6% vs 3.6%, P = 0.003). Mean BMI-for-age z scores increased significantly (-0.03 ± 0.94 vs 0.27 ± 0.82, P = 0.03); however, height-for-age z scores, weight-for-age z scores, and percent of calories from enteral intake were not significantly different after therapy. Antibiotic regimens remained highly variable.

CONCLUSIONS

Children with IF and culture-positive SBBO showed significant improvement in symptoms and BMI-for-age z scores after duodenal culture with subsequent targeted antibiotic therapy. Longer follow-up may be needed to detect improvements in linear growth and percent of calories from enteral feeds. Antibiotic regimens remain highly variable. Long-term consequences of chronic antimicrobial therapy, including antimicrobial resistance, remain unknown. Prospective studies focused on standardizing duodenal sampling technique, correlating culture and pathology data, and evaluating antibiotic resistance patterns are needed.

Management of pediatric intestinal failure related to short bowel syndrome

Intestinal failure (IF) secondary to short bowel syndrome is a challenging and complex medical condition with significant risk for surgical and medical complications. Significant advancements in the care of this patient population have led to improved survival rates. Due to their intensive medical needs children with IF are at risk for long-term complications that require comprehensive management and close monitoring. The purpose of this paper is to review the available literature emphasizing the surgical aspects of care for children with IF secondary to short bowel syndrome. A key priority in the surgical care of this patient population includes strategies to preserve available bowel and maximize its function. Utilization of novel surgical techniques and autologous bowel reconstruction can have a significant impact on children with IF secondary to short bowel syndrome related to the function of their bowel and ability to achieve enteral autonomy. It is also important to understand the potential long-term complications to ensure strategies are put in place to mitigate risk with early detection to improve long-term outcomes.

The Importance of the ileocecal valve and colon in achieving intestinal independence in infants with short bowel syndrome

PURPOSE

Infants with short bowel syndrome (SBS) wean from parenteral nutrition (PN) support at variable rates. Small bowel length is a predictor, but the importance of the ileocecal valve (ICV) and colon are unclear. We aim to determine if the ICV and/or colon predict enteral autonomy.

METHODS

Infants from a single intestinal rehabilitation program were retrospectively reviewed. Etiology of SBS, intestinal anatomy, and duration of nutritional support were collected for three years. The primary outcome was time to full enteral nutrition. ANCOVA and Cox proportional hazards model were used, with p < 0.05 significant.

RESULTS

55 infants with SBS were included. After accounting for the effect of small bowel, PN duration was shorter for infants with the ICV compared to those without (mean 218 vs. 538 days, p = 0.003), and had a more significant effect on infants with ≤50% of small bowel. Increased small bowel length was a positive predictor of weaning. Patients with ≤50% of colon spent less time on PN with the ICV, compared to without (mean 220 vs 715 days, p = 0.009).

CONCLUSIONS

Preservation of the ICV was associated with shorter duration of PN support, while colon was not. Small bowel length is a positive predictor of enteral autonomy.

LEVEL OF EVIDENCE

Level III retrospective comparative study TYPE OF STUDY: Retrospective review.

Review article: insights into the bile acid-gut microbiota axis in intestinal failure-associated liver disease-redefining the treatment approach

BACKGROUND

Intestinal failure-associated liver disease (IFALD) increases mortality of patients with intestinal failure (IF), but lacks effective prevention or treatment approaches. Bile acids, gut microbiota and the host have close and complex interactions, which play a central role in modulating host immune and metabolic homeostasis. Increasing evidence suggests that derangement of the bile acid-gut microbiota (BA-GM) axis contributes to the development of IFALD.

AIMS

To review the BA-GM axis in the pathogenesis and clinical applications of IFALD, and to explore future directions for effective disease management.

METHODS

We conducted a literature search on bile acid and gut microbiota in IF and liver diseases.

RESULTS

The BA-GM axis demonstrates a unique IF signature manifesting as an increase in primary-to-secondary bile acids ratio, disturbed enterohepatic circulation, blunted bile acid signalling pathways, gut microbial dysbiosis, and altered microbial metabolic outputs. Bile acids and gut microbiota shape the compositional and functional alterations of each other in IF; collaboratively, they promote immune dysfunction and metabolic aberration in the liver. Diagnostic markers and treatments targeting the BA-GM axis showed promising potential in the management of IFALD.

CONCLUSIONS

Bile acids and gut microbiota play a central role in the development of IFALD and make attractive biomarkers as well as therapeutic targets. A multitarget, individualised therapy aiming at different parts of the BA-GM axis may provide optimal clinical benefits and requires future investigation.

Fecal microbiome alterations in pediatric patients with short bowel syndrome receiving a rotating cycle of gastrointestinal prophylactic antibiotics

BACKGROUND

Pediatric patients with short bowel syndrome (SBS) are at risk of developing small intestinal bacterial overgrowth (SIBO). Prevention of SIBO using cyclic enteric antibiotics has been implemented to control the balance in microbial ecosystems, although its effectiveness has not been well studied.

PURPOSE

This study aimed to explore the change in the gut microbial composition in SBS patients during cyclic antibiotic phases and antibiotic-free period, and to compare the microbiota composition between healthy controls and SBS patients.

METHOD

SBS patients taking oral metronidazole alternating with trimethoprim-sulfamethoxazole (TMP-SMT) and antibiotic-free conditions as a '10-day cyclic protocol' were involved in fecal microbiome study using Illumina 16S sequencing.

RESULTS

When healthy control possessed the majority of Bacteroidetes spp. (54%) and Firmicutes spp. (33%), the microbial composition in SBS patients especially Firmicutes spp. and Proteobacteria spp. was prominently changed in each phase of treatment. In antibiotic-free period, SBS patients displayed 49% Firmicutes and 36% Proteobacteria. However, higher Proteobacteria than Firmicutes were detected at the commencement of metronidazole (58% versus 33%). Similarly, 56% Proteobacteria and 27% Firmicutes were found during TMP-SMT. Escherichia coli increased prominently during the antibiotic periods.

CONCLUSION

Prophylactic antibiotics change the gut microbiota composition in an unfavorable direction, especially when repeatedly used for a long period. This practice should be reconsidered.

LEVEL OF EVIDENCE

III.

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.

New insights into intestinal failure-associated liver disease in adults: A comprehensive review of the literature

Intestinal failure-associated liver disease (IFALD) remains one of the most common and serious complications of parenteral nutrition (PN), causing a wide spectrum of hepatic manifestations from steatosis and mild cholestasis to portal hypertension and end-stage liver failure. The prevalence of IFALD depends on the diagnostic criteria and ranges from 4.3% to 65%. Moreover, many factors are shown to contribute to its development, including nutrient deficiencies, toxicity of PN, infections, and alterations of bile acid metabolism and gut microbiota. Prevention and management of IFALD aim at ameliorating or eliminating the risk factors associated with IFALD. The use of PN formulations with a lower ratio omega-6-to-omega-3 polyunsaturated fatty acids, cycle PN, optimization of enteral stimulation and prevention and early treatment of infections constitute the main therapeutic targets. However, failure of improvement and severe IFALD with end-stage liver failure should be considered as the indications of intestinal transplantation. The aim of this review is to provide an update of the epidemiology, pathophysiology, and diagnosis of IFALD in the adult population as well as to present a clinical approach of the therapeutic strategies of IFALD and present novel therapeutic targets.

Gut Microbial Dysbiosis in the Pathogenesis of Gastrointestinal Dysmotility and Metabolic Disorders

Of all microorganisms in the human body, the largest and most complex population resides in the gastrointestinal (GI) tract. The gut microbiota continuously adapts to the host environment and serves multiple critical functions for their hosts, including regulating host immunity, procuring energy from food, and preventing the colonization of pathogens. Mounting evidence has suggested gut microbial imbalance (dysbiosis) as a core pathophysiology in the development of GI motility and metabolic disorders, such as irritable bowel syndrome and diabetes. Current research has focused on discovering associations between these disorders and gut microbial dysbiosis; however, whether these associations are a consequence or cause is still mostly unexplored. State-of-the-art studies have investigated how gut microbes communicate with our body systems through microbiota-derived metabolites and how they are able to modulate host physiology. There is now mounting evidence that alterations in the composition of small intestinal microbes have an association with GI dysmotility and metabolic disorders. Although treatment options for gut microbial dysbiosis are currently limited, antibiotics, fecal microbiota transplantation, probiotics, and dietary interventions are currently the best options. However, treatment with broad-spectrum antibiotics has been viewed with skepticism due to the risk of developing antibiotic resistant bacteria. Studies are warranted to elucidate the cellular and molecular pathways underlying gut microbiota-host crosstalk and for the development of a powerful platform for future therapeutic approaches. Here, we review recent literature on gut microbial alterations and/or interactions involved in the pathophysiology of GI dysmotility and metabolic disorders.

Anti-TNF-α Therapy Exerts Intestinal Anti-inflammatory and Anti-apoptotic Effects After Massive Bowel Resection in a Rat

OBJECTIVES

The aim of this study was to examine the effect of massive small bowel resection on proinflammatory cytokine intestinal expression and the effect of anti-TNF-α antibodies (ATA) on intestinal inflammation, epithelial cell turnover, and intestinal adaptation after bowel resection in rats.

METHODS

Male Sprague-Dawley rats were divided into 4 experimental groups: Sham-rats underwent bowel transection; Sham-ATA rats underwent bowel transection and were treated with ATA; SBS-animals underwent 75% bowel resection; and SBS-ATA rats underwent bowel resection and were treated with ATA similarly to Group B. Parameters of intestinal adaptation, enterocyte proliferation, and apoptosis were determined at sacrifice. TNF-α and apoptosis-related gene and protein levels were determined by Illumina's Digital Gene Expression (DGE) analysis, Real Time PCR, Western blotting, and immunohistochemistry.

RESULTS

From 25 genes related to TNF-α signalling that were investigated, 8 genes in the jejunum and 10 genes in the ileum were found to be up-regulated in resected versus sham animals. SBS rats demonstrated a significant increase in tissue and plasma TNF-α, IL-6 levels, intestinal mucosal TNF-α related gene expression, and microscopic parameters of inflammation. Treatment of resected animals with ATA resulted in a significant decrease in TNF-α levels, intestinal mucosal TNF-α-related gene expression, decreased number of intraepithelial lymphocytes and macrophages, and lower apoptotic index compared with SBS animals.

CONCLUSIONS

In a rat model of SBS, ATA decreased plasma and tissue TNF-α levels, diminished mucosal inflammation, and inhibited cell apoptosis. Anti-apoptotic effects of ATA appear to be associated with an inhibited extrinsic apoptotic pathway.

Intestinal Failure-Associated Liver Disease in Neonates

Intestinal failure-associated liver disease (IFALD) is common in neonates who suffer from intestinal failure and rely on parenteral nutrition. The etiology is multifactorial, relating to the infant's underlying cause of intestinal failure and other infant factors such as prematurity. Management of the disease includes transitioning to enteral feedings as soon as is safe for the infant. In infants who continue to rely on parenteral nutrition, alternative lipid emulsions and other medications may be used. This article reviews the epidemiology and factors that contribute to IFALD in neonates, in addition to management strategies.

Serum Scoring and Quantitative Magnetic Resonance Imaging in Intestinal Failure-Associated Liver Disease: A Feasibility Study

(1) Background: Intestinal failure-associated liver disease (IFALD) in adults is characterized by steatosis with variable progression to fibrosis/cirrhosis. Reference standard liver biopsy is not feasible for all patients, but non-invasive serological and quantitative MRI markers for diagnosis/monitoring have not been previously validated. Here, we examine the potential of serum scores and feasibility of quantitative MRI used in non-IFALD liver diseases for the diagnosis of IFALD steatosis; (2) Methods: Clinical and biochemical parameters were used to calculate serum scores in patients on home parenteral nutrition (HPN) with/without IFALD steatosis. A sub-group underwent multiparameter quantitative MRI measurements of liver fat fraction, iron content, tissue T1, liver blood flow and small bowel motility; (3) Results: Compared to non-IFALD (n = 12), patients with IFALD steatosis (n = 8) demonstrated serum score elevations in Enhanced Liver Fibrosis (p = 0.032), Aspartate transaminase-to-Platelet Ratio Index (p < 0.001), Fibrosis-4 Index (p = 0.010), Forns Index (p = 0.001), Gamma-glutamyl transferase-to-Platelet Ratio Index (p = 0.002) and Fibrosis Index (p = 0.001). Quantitative MRI scanning was feasible in all 10 sub-group patients. Median liver fat fraction was higher in IFALD steatosis patients (10.9% vs 2.1%, p = 0.032); other parameter differences were non-significant; (4) Conclusion: Serum scores used for non-IFALD liver diseases may be useful in IFALD steatosis. Multiparameter MRI is feasible in patients on HPN.

Vitamin C in Home Parenteral Nutrition: A Need for Monitoring

To date, there are no recommendations about screening plasma vitamin C concentration and adjust its supplementation in patients on long-term home parenteral nutrition (HPN). The aim of this study was to evaluate vitamin C status and determine if a commercial multivitamin preparation (CMVP) containing 125 mg of vitamin C is sufficient in stable patients on HPN. All clinically stable patients receiving HPN or an intravenous fluid infusion at least two times per week for at least 6 months, hospitalized for nutritional assessment, were retrospectively included, for a total of 186 patients. We found that 29% of the patients had vitamin C insufficiency (i.e., <25 µmol/L). In univariate analysis, C-reactive protein (CRP) (p = 0.002) and intake of only 125 mg of vitamin C (p = 0.001) were negatively associated with vitamin C levels, and duration of follow-up in our referral center (p = 0.009) was positively associated with vitamin C levels. In multivariate analysis, only CRP (p = 0.001) and intake of 125 mg of vitamin C (p < 0.0001) were independently associated with low plasma vitamin C concentration. Patients receiving only CMVP with a low plasma vitamin C level significantly received personal compounded HPN (p = 0.008) and presented an inflammatory syndrome (p = 0.002). Vitamin C insufficiency is frequent in individuals undergoing home parenteral nutrition; therefore, there is a need to monitor plasma vitamin C levels, especially in patients on HPN with an inflammatory syndrome and only on CMVP.

Effects of high-fat diet on liver injury after small bowel resection

BACKGROUND

The optimal regimen for enteral nutritional support in the management of children with short bowel syndrome (SBS) is not well characterized. A high fat, enteral diet is theoretically beneficial due to increased caloric density and enhanced structural adaptation. We therefore sought to determine the long-term effects of a high fat diet (HFD) on liver injury, a common complication of SBS, compared to a standard chow (SC) diet.

METHODS

Using a parenteral nutrition-independent model of resection-associated liver injury, C57BL/6 mice underwent a sham operation or a 50% or 75% proximal small bowel resection (SBR). Mice in each group were then fed either a HFD (35% kcal fat) or SC (13% kcal fat). At post-operative week 15, markers of liver injury were quantified.

RESULTS

Liver triglyceride levels were increased from 7- to 19-fold in mice on the HFD compared to mice fed SC in the sham, 50%, and 75% resection groups. Serum ALT (2.2-fold increase in 75% resected mice compared to sham controls) and AST (2.0- and 2.7-fold increases in 50% and 75% resected mice, respectively) levels as well as fibrotic liver staining were elevated only in resected mice fed a HFD.

CONCLUSION

Long-term enteral feeding of HFD in our murine SBS model is associated with hepatic steatosis and liver injury. Our observation that liver steatosis and injury occur independent of parenteral nutrition suggests that enteral feeding composition and magnitude of intestinal loss may make a significant contribution to intestinal failure-associated liver disease.

Intestinal failure-associated liver disease (IFALD): insights into pathogenesis and advances in management

Premature infants and children with intestinal failure (IF) or short bowel syndrome are susceptible to intestinal failure-associated liver disease (IFALD, previously referred to as parenteral nutrition-associated liver disease, or PNALD). IFALD in children is characterized by progressive cholestasis and biliary fibrosis, and steatohepatitis in adults, and is seen in individuals dependent upon prolonged administration of PN. Many factors have been proposed as contributing to the pathogenesis of IFALD. In recent years, the focus has been on the potential synergistic roles of the intestinal microbiome, increased intestinal permeability, activation of hepatic innate immune pathways, and the use of intravenous soybean-oil-based intravenous lipid emulsions (SO-ILE). In vitro and in vivo studies have identified stigmasterol, a component of the plant sterols present in SO-ILE, as playing an important role. Although various strategies have been adopted to prevent or reverse IFALD, most suffer from a lack of strong evidence supported by well-designed, prospective clinical trials with clearly defined endpoints. Reduction in the amount of SO-ILEs or replacement with non-SO-ILEs has been shown to reverse IFALD although safety and long-term effectiveness have not been studied. Medical and surgical modalities to increase intestinal adaptation, advance enteral feedings, and prevent central line bloodstream infections are also important preventative strategies. There is a continued need to conduct high-quality, prospective trials with clearly define outcome measures to ascertain the potential benefits of these strategies.

Factors Related to the Development of Small-Bowel Bacterial Overgrowth in Pediatric Intestinal Failure: A Retrospective Cohort Study

BACKGROUND

Small bowel bacterial overgrowth (SBBO) is a challenge in the management of pediatric intestinal failure (PIF). Our goal was to determine the proportion of patients treated for SBBO and factors related to its development.

METHODS

We completed a retrospective analysis of PIF patients referred between 2008 and 2014. Data were collected on factors related to intestinal failure (IF) and SBBO. The cohort was stratified on the diagnosis of SBBO and refractory SBBO. Statistical testing completed using t-test, χ² test, and logistic regression.

RESULTS

Thirty-five of 102 patients developed SBBO (34%), and 16 (16%) had refractory SBBO. SBBO was more likely in gastroschisis (40.0% vs 19.4%, P = .025), a shorter residual small bowel (SB) (45.4% vs 66.5%, P = .004), and patients were less likely to wean from parenteral nutrition (PN) (51.4% vs 85.1%, P < .0001). Refractory SBBO patients were likely to have gastroschisis (50.0% vs 22.1%, P = .020) and a shorter residual SB and large bowel remaining (23.2% vs 65.9%, P < .0001 and 60.6% vs 79.4%, P = .03, respectively) and less likely to wean from PN (37.5% vs 80.2%, P = .001). Logistic regression demonstrated that longer SB residual was protective (P = .001; odds ratio [OR], 0.95; 95% CI, 0.93-0.99), and short bowel syndrome (SBS) as a cause of IF was a risk factor (P = .001; OR, 0.04; 95% CI, 0.01-0.27).

CONCLUSION

A longer SB remnant was protective against SBBO. Patients with SBBO were more likely to have PIF caused by SBS.

Growth in Infants and Children With Intestinal Failure-associated Liver Disease Treated With Intravenous Fish Oil

BACKGROUND

Infants with intestinal failure (IF) and IF-associated liver disease (IFALD) are at risk for poor somatic growth because of increased metabolic demands, inadequate intake, intestinal malabsorption, chronic liver disease and other comorbidities. There are limited data on the nutritional adequacy of intravenous fish oil lipid emulsion (FOLE) compared with standard soybean oil lipid emulsion (SOLE) in the setting of intestinal failure.

AIMS

To describe growth patterns in a large cohort of infants with IFALD treated with FOLE.

METHODS

We compared growth data from infants enrolled in a single-center, prospective FOLE study to published norms, as well as to a multicenter, historical cohort of infants with IF treated with SOLE.

RESULTS

One hundred thirty-eight infants with IFALD were treated with FOLE and 108 with SOLE. Compared with normative growth curves from WHO and published preterm data, infants in both groups from 6 to 11 months postmenstrual age exhibited declines in mean weight- and length-for-age z scores. At 24 months postmenstrual age compared with WHO growth data, infants treated with FOLE had a mean (95% confidence interval [CI]) weight-for-age z-score of 0.13 (-0.18 to 0.45) and length-for-age z-score of 0.07 (-0.33 to 0.47). In comparison, at 24 months postmenstrual age, infants treated with SOLE had a mean weight for age z-score of -0.93 (-1.20 to -0.67) and mean length for age z-score of -2.33 (-2.75 to -1.91). Independent predictors of higher weight, length and head circumference z-scores included older postmenstrual age at baseline, fewer central line-associated blood stream infections, resolution of cholestasis, type of intravenous fat emulsion (FOLE vs SOLE) and female sex.

CONCLUSIONS

Infants with IFALD treated with FOLE showed comparable somatic growth to those treated with SOLE in early infancy, and improved somatic growth up to 24 months of age, supporting its wider use in this patient population.

Etiology and Medical Management of Pediatric Intestinal Failure

Pediatric intestinal failure occurs when gut function is insufficient to meet the growing child's hydration and nutrition needs. After massive bowel resection, the remnant bowel adapts to lost absorptive and digestive capacity through incompletely defined mechanisms newly targeted for pharmacologic augmentation. Management seeks to achieve enteral autonomy and mitigate the development of comorbid disease. Care has improved, most notably related to reductions in blood stream infection and liver disease. The future likely holds expansion of pharmacologic adaptation augmentation, refinement of intestinal tissue engineering techniques, and the development of a learning health network for efficient multicenter study and care improvement.

Small intestinal bacterial overgrowth in children with intestinal failure on home parenteral nutrition

Background and Aim

Children with intestinal failure (IF) have abnormal intestinal anatomy, secretion, or motility, which impairs homeostatic mechanisms and can lead to small intestinal bacterial overgrowth (SIBO). We sought to describe clinical features at the time of clinically suspected SIBO by experienced clinicians in children with IF on home parenteral nutrition (PN), review specific challenges of diagnostic testing in this population, and describe potential new diagnostic surrogate markers.

Methods

A descriptive single‐center retrospective chart review was performed during all episodes of clinically suspected SIBO over 33 months. Information was recorded on clinical symptoms, and diagnostic tests performed.

Results

Of all patients on home PN, 71% (12/17) had at least one episode of clinically suspected SIBO (mean 1 episode/year, range 1–7); 50% of patients had short bowel syndrome (SBS), and 50% had non‐SBS IF. The average reported symptoms per episode were 1.9 (range 1–5). Children with SBS reported fewer symptoms per episode (1.5) than children with non‐SBS IF (2.3). Diarrhea was the most commonly reported symptom, particularly in children with SBS.

Conclusions

Children with IF on home PN are a high‐risk group for SIBO. Clinical features of SIBO vary depending on the cause of IF and may mimic symptoms of the underlying condition. Diagnostic tests have innate challenges in this group, and a strong index of clinical suspicion is paramount. Further research is recommended into potential new surrogate markers (urinary metabolite screen, gastric aspirate) for this diagnostically challenging population.

Short Bowel Syndrome

Purpose of Review

Short gut syndrome is life-altering and life-threatening disease resulting most often from massive small bowel resection. Recent advances in understanding of the perturbed physiology in these patients have translated into improved care and outcomes. This paper seeks to review the advances of care in SBS patients.

Recent Findings

Anatomic considerations still predominate the early care of SBS patients, including aggressive preservation of bowel and documentation of remnant bowel length and quality. Intestinal adaptation is the process by which remnant bowel changes to fit the physiologic needs of the patient. Grossly, the bowel dilates and elongates to increase intestinal weight and protein content. Architectural changes are noted, such as villus lengthening and deepening of crypts. In addition, gene expression changes occur that function to maximize nutrient uptake and fluid preservation. Management is aimed at understanding these physiologic changes and augmenting them whenever possible in an effort to gain enteral autonomy. Complication mitigation is key, including avoidance of catheter complications, bloodstream infections, cholestasis, and nutrient deficiencies.

Summary

Multidisciplinary teams working together towards intestinal rehabilitation have shown improved outcomes. Today's practioner needs a current understanding of the ever-evolving care of these patients in order to promote enteral autonomy, recognize complications, and counsel patients and families appropriately.

The Structure and Function of the Human Small Intestinal Microbiota: Current Understanding and Future Directions

Despite growing literature characterizing the fecal microbiome and its association with health and disease, few studies have analyzed the microbiome of the small intestine. Here, we examine what is known about the human small intestinal microbiota in terms of community structure and functional properties. We examine temporal dynamics of select bacterial populations in the small intestine, and the effects of dietary carbohydrates and fats on shaping these populations. We then evaluate dysbiosis in the small intestine in several human disease models, including small intestinal bacterial overgrowth, short-bowel syndrome, pouchitis, environmental enteric dysfunction, and irritable bowel syndrome. What is clear is that the bacterial biology, and mechanisms of bacteria-induced pathophysiology, are enormously broad and elegant in the small intestine. Studying the small intestinal microbiota is challenged by rapidly fluctuating environmental conditions in these intestinal segments, as well as the complexity of sample collection and bioinformatic analysis. Because the functionality of the digestive tract is determined primarily by the small intestine, efforts must be made to better characterize this unique and important microbial ecosystem.

The bacterial communities of the small intestine and stool in children with short bowel syndrome

Short bowel syndrome (SBS) presents an increasing problem in pediatrics. SBS often results from surgical resection of necrotic bowel following necrotizing enterocolitis or treatment of anatomic gastrointestinal defects. SBS is associated with significant morbidity and mortality, and creates substantial burdens for patients, families, and the health system. Recent reports have demonstrated that the fecal microbiome of children with SBS is significantly different from healthy control and severe intestinal microbial imbalances is associated with poor growth. We hypothesized that children with SBS and adverse clinical features such as PN dependent, shorter bowel length and lack of ileocecal valve would demonstrate more gut dysbiosis compare with the SBS non-PN dependent. An improved understanding of SBS pathogenesis would enhance management and potentially suggest new interventions. We studied microbial communities of SBS and control non-SBS patients from the jejunum, obtained endoscopically or by ostomy aspiration, and stool. We enrolled SBS patients who did and did not require parenteral nutrition (PN), as a surrogate marker for the seriousness of their disease. We studied the microbiota using high-throughput DNA sequencing of 16S rRNA genes and statistical analyses. We found that microbial diversity was significantly greater in jejunal aspirate than in stool samples in SBS patients, unlike non-SBS patients; that SBS patients receiving enteral feeds had greater diversity, and that SBS patients on PN and enteral feeds had lower differences in diversity in jejunal vs. stool samples. We found a trend toward increased diversity in patients with an intact ileocecal valve, and found that certain taxa were more abundant in the certain sample types, and in SBS patients vs. non-SBS patients. SBS patients have lower microbial diversity, especially patients with more severe disease, patients requiring PN, and those lacking an ileocecal valve. SBS patients, particularly those with more complex characteristics, exhibit differences in their intestinal microbiota. Particular individual taxa were over- and under-represented in patients with more unfavorable disease. While diminished diversity and alterations in microbiota composition are likely consequences of SBS, future efforts aimed at increasing microbial diversity and interventions targeting specific microbiota characteristics might constitute a testable approach to ameliorate some clinical SBS clinical consequences.

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.

Small Intestinal Bacterial Overgrowth in Patients With Cirrhosis

Small intestinal bacterial overgrowth (SIBO) is defined by increased density and/or abnormal composition of microbiota in the small bowel. SIBO is often encountered in patients with cirrhosis as a result of impaired intestinal motility and delayed transit time, both of which are exacerbated by more severe liver disease. Additional risk factors for SIBO commonly encountered in cirrhotic patients include coexisting diabetes, autonomic neuropathy, and/or alcoholic use. Diagnosis of SIBO is performed by breath testing or jejunal aspiration, the gold standard. In cirrhotic patients, the presence of SIBO can lead to profound clinical consequences. Increased intestinal permeability in these patients predisposes to bacterial translocation into the systemic circulation. As a result, SIBO is implicated as a significant risk factor in the pathogenesis of both spontaneous bacterial peritonitis and hepatic encephalopathy in cirrhotics. Antibiotics, especially rifaximin, are the best studied and most effective treatment options for SIBO. However, prokinetics, probiotics, nonselective beta-blockers, and treatment of underlying liver-related pathophysiology with transjugular intrahepatic portosystemic shunt placement or liver transplantation are also being investigated. This review will discuss the risk factors, diagnosis, manifestations in cirrhosis, and treatment options of SIBO.

Visceral transplantation in patients with intestinal-failure associated liver disease: Evolving indications, graft selection, and outcomes

Intestinal failure (IF)-associated liver disease (IFALD) is widely recognized as a lethal complication of long-term parenteral nutrition. The pathophysiology of IFALD is poorly understood but appears to be multifactorial and related to the inflammatory state in the patient with IF. Visceral transplant for IFALD includes variants of intestine, liver, or combined liver-intestine allografts. Graft selection for an individual patient depends on the etiology of IF, abdominal and vascular anatomy, severity of IFALD, and potential for intestinal rehabilitation. The past decade has witnessed dramatic improvement in the management of IFALD, principally due to improved lipid emulsion formulations and the multidisciplinary care of the patient with IF. As the recognition and treatment of IFALD continue to improve, the requirement of liver-inclusive visceral grafts appears to be decreasing, representing a paradigm shift in the care of the patient with IF. This review highlights the current indications, graft selection, and outcomes of visceral transplantation for IFALD.

Prevention and Treatment of Intestinal Failure-Associated Liver Disease in Children

Intestinal failure-associated liver disease (IFALD) is a threatening complication for children on long-term parenteral nutrition because of intestinal failure. When progressive and intractable, it may jeopardize intestinal rehabilitation and lead to combined liver and intestinal transplantation. The institution of dedicated intestinal failure centers has dramatically decreased the incidence of such complication. IFALD may rapidly fade away if very early management aimed at preventing progression to end-stage liver disease is provided. In this review, we address the etiology and risk factors of IFALD in order to introduce pillars of prevention (nutritional management and catheter-related infections control). The latest evidence of therapeutic strategies, such as medical and surgical treatments, is also discussed.

Macrophage-derived IL-1β/NF-κB signaling mediates parenteral nutrition-associated cholestasis

In infants intolerant of enteral feeding because of intestinal disease, parenteral nutrition may be associated with cholestasis, which can progress to end-stage liver disease. Here we show the function of hepatic macrophages and phytosterols in parenteral nutrition-associated cholestasis (PNAC) pathogenesis using a mouse model that recapitulates the human pathophysiology and combines intestinal injury with parenteral nutrition. We combine genetic, molecular, and pharmacological approaches to identify an essential function of hepatic macrophages and IL-1β in PNAC. Pharmacological antagonism of  IL-1 signaling or genetic deficiency in CCR2, caspase-1 and caspase-11, or IL-1 receptor (which binds both IL-1α and IL-1β) prevents PNAC in mice. IL-1β increases hepatocyte NF-κB signaling, which interferes with farnesoid X receptor and liver X receptor bonding to respective promoters of canalicular bile and sterol transporter genes (Abcc2, Abcb11, and Abcg5/8), resulting in transcriptional suppression and subsequent cholestasis. Thus, hepatic macrophages, IL-1β, or NF-κB may be targets for restoring bile and sterol transport to treat PNAC.

Small Intestinal Bacterial Overgrowth: Nutritional Implications, Diagnosis, and Management

Small intestinal bacterial overgrowth (SIBO), characterized by the presence of excessive bacteria in the small intestine, is typically described as a malabsorptive syndrome occurring in the context of gut stasis syndromes. SIBO is now considered to be a disorder associated with diverse clinical conditions without classic risk factors for SIBO and a cause of several nonspecific gastrointestinal and nongastrointestinal symptoms. Because there is currently no gold standard for diagnosing SIBO, its prevalence and role in the pathogenesis of other diseases remain uncertain; as does optimal treatment of patients with relapsing symptoms.

Long-term outcomes of pediatric intestinal failure

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

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

OBJECTIVE

To analyze risk factors and prognostic significance of small bowel (SB) dilatation in children with short bowel syndrome (SBS).

BACKGROUND

In SBS, the remaining SB may dilate as part of intestinal adaptation. The impact of dilatation on parenteral nutrition (PN) dependence and survival has not been studied systematically.

METHODS

SB diameter of SBS children (n = 61) was measured in contrast SB series (n = 169, median age 0.94, range 0.32-2.7 years) during 2002 to 2015, and expressed as millimeters (SB width) and as ratio to L5 vertebra height (SB diameter ratio). Linear regression was used to examine risk factors for dilatation. PN weaning and survival were analyzed with Cox proportional hazards regression.

RESULTS

Maximal SB diameter ratio during follow-up was predicted by PN dependence and SB atresia, while maximal absolute SB width by birth weight, age, PN duration, and remaining bowel length. Weaning off PN was 14-fold more likely in patients with maximal SB diameter ratio <2.00 compared with >3.00 (P = 0.005), and 5.4-fold more likely when maximal SB width was <20 mm compared with >30 mm (P = 0.023). After adjustment for age, remaining SB length, and the presence of ileocecal valve, both estimates of maximal SB dilatation remained significant independent predictors for weaning off PN. When all measurements were included, the cumulative survival was worse if SB diameter ratio exceeded 2.00 (P = 0.002-0.042).

CONCLUSIONS

SB dilatation predicts prolonged PN duration and decreased survival in SBS children. Measurement of maximal SB diameter standardized to L5 vertebra height may be a valuable objective tool for patient follow-up and assessment of prognosis.

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.

Long-Term Results of Serial Transverse Enteroplasty with Neovalve Creation for Extreme Short Bowel Syndrome: Report of Two Cases

Objective

The aim of this article was to determine whether serial transverse enteroplasty (STEP) and the creation of a new ileocecal valve in extreme short bowel syndrome (SBS) cases (<45 cm) is effective in intestinal adaptation and improvement of nutritional parameters and serum citrulline levels.

Patients and Methods

We present 2 cases of SBS treated with STEP. Enterectomy was performed for massive intestinal ischemia secondary to a gastrointestinal stromal tumor in the first case and to catastrophic antiphospholipid syndrome in the second. After enterectomy, the short residual bowel measured 34 cm in the first patient and 45 cm in the second. In both cases STEP, cholecystectomy, and gastrostomy were performed. In the first case a Brooke neovalve was created, and in the other the ileocecal valve was preserved.

Results

Both patients could finally be weaned off total parenteral nutrition (TPN) and gastrostomy feeding, maintaining a good nutritional status 1 year after surgery.

Conclusions

In extreme SBS, a minimum length of 80–90 cm of functioning small bowel and an intact ileocecal valve are necessary. We plead for the use of STEP with preservation of the ileocecal valve or creation of a neovalve using the Brooke technique in order to achieve the ultimate goal, which is to wean patients off TPN. After a critical review of different surgical techniques, a treatment algorithm is proposed.

Pediatric intestinal failure-associated liver disease

PURPOSE OF REVIEW

The goal of this review is to provide updates on the definition, pathophysiology, treatment, and prevention of intestinal failure-associated liver disease (IFALD) that are relevant to care of pediatric patients.

RECENT FINDINGS

Current literature emphasizes the multifactorial nature of IFALD. The pathogenesis is still largely unknown; however, molecular pathways have been identified. Key to these pathways are proinflammatory cytokines involved in hepatic inflammation and bile acids synthesis such as Toll-like receptor 4 and farnesoid X receptor, respectively. Research for prevention and treatment is aimed at alleviating risk factors associated with IFALD, principally those associated with parental nutrition. Multiple nutrients and amino acids are relevant to the development of IFALD, but lipid composition has been the primary focus. Lipid emulsions with a lower ratio of omega-6-to-omega-3 polyunsaturated fatty acids (FAs) appear to improve bile flow and decrease intrahepatic inflammation. Long-term consequences of these alternative lipid emulsions are yet to be determined.

SUMMARY

IFALD remains the greatest contributor of mortality in patients with intestinal failure. Many factors contribute to its development, namely, alterations in the gut microbiome, sepsis, and lack of enteral intake. Novel combinations of lipid formulations are promising alternatives to purely soy-based formulas to reduce cholestasis.

Redefining short bowel syndrome in the 21st century

In 1968, Wilmore and Dudrick reported an infant sustained by parenteral nutrition (PN) providing a potential for survival for children with significant intestinal resections. Increasing usage of TPN over time led to some patients developing Intestinal Failure Associated Liver Disease (IFALD), a leading cause of death and indication for liver/intestinal transplant. Over time, multidisciplinary teams called Intestinal Rehabilitation Programs (IRPs) began providing meticulous and innovative management. Usage of alternative lipid emulsions and lipid minimization strategies have resulted in the decline of IFALD and an increase in long-term and transplant-free survival, even in the setting of ultrashort bowel (< 20 cm). Autologous bowel reconstructive surgeries, such as the serial tapering enteroplasty procedure, have increased the likelihood of achieving enteral autonomy. Since 2007, the number of pediatric intestinal transplants performed has sharply declined and likely attributed to the newer innovations healthcare. Recent data support the need for changes in the listing criteria for intestinal transplantation given the overall improvement in outcomes. Over the last 50 y, the diagnosis of short bowel syndrome has changed from a death sentence to one of hope with a vast improvement of quality of life and survival.

Intestinal Microbiota Signatures Associated With Histological Liver Steatosis in Pediatric-Onset Intestinal Failure

BACKGROUND

Intestinal failure (IF)-associated liver disease (IFALD) is the major cause of mortality in IF. The link between intestinal microbiota and IFALD is unclear.

METHODS

We compared intestinal microbiota of patients with IF (n = 23) with healthy controls (n = 58) using culture-independent phylogenetic microarray analysis. The microbiota was related to histological liver injury, fecal markers of intestinal inflammation, matrix metalloproteinase 9 and calprotectin, and disease characteristics.

RESULTS

Overabundance of Lactobacilli, Proteobacteria, and Actinobacteria was observed in IF, whereas bacteria related to Clostridium clusters III, IV, and XIVa along with overall diversity and richness were reduced. Patients were segregated into 3 subgroups based on dominating bacteria: Clostridium cluster XIVa, Proteobacteria, and bacteria related to Lactobacillus plantarum. In addition to liver steatosis and fibrosis, Proteobacteria were associated with prolonged current parenteral nutrition (PN) as well as liver and intestinal inflammation. Lactobacilli were related to advanced steatosis and fibrosis mostly after weaning off PN without associated inflammation. In multivariate permutational analysis of variance, liver steatosis, bowel length, PN calories, and antibiotic treatment best explained the microbiota variation among patients with IF.

CONCLUSIONS

Intestinal microbiota composition was associated with liver steatosis in IF and better predicted steatosis than duration of PN or length of the remaining intestine. Our results may be explained by a model in which steatosis is initiated during PN in response to proinflammatory lipopolysaccharides produced by Proteobacteria and progresses after weaning off PN, as the L plantarum group Lactobacilli becomes dominant and affects lipid metabolism by altering bile acid signaling.

High Prevalence of Eosinophilic Gastrointestinal Disease in Children With Intestinal Failure

OBJECTIVES

The aim of the present study was to describe the prevalence and clinical features of gastrointestinal (GI) eosinophilic inflammation among pediatric patients with intestinal failure (IF).

METHODS

Medical records of all patients studied in our institution's IF program who underwent GI endoscopy over a 15-year period were reviewed, and clinical, pathologic, nutrition, and laboratory data collected.

RESULTS

One hundred five patients underwent 208 GI endoscopic procedures with biopsy. The overall prevalence of eosinophilic inflammation, defined as increased eosinophils in at least 1 tissue type on at least 1 endoscopy, was 39 of 105 (37%). The tissue-specific prevalence of eosinophilic inflammation ranged widely, with the colon/rectosigmoid being the most common (18/68, 26%), followed by the esophagus (17/83, 20%), ileum (9/54, 17%), duodenum (4/83, 5%), and stomach (3/83, 4%). Higher peripheral eosinophil count and hematochezia were associated with eosinophilic inflammation in the colon (P = 0.002 and 0.0004, respectively). The use of a strict elemental diet for 3 months before endoscopy was not associated with a decreased frequency of eosinophilic inflammation in any tissue.

CONCLUSIONS

Eosinophilic inflammation is a common histopathological finding in patients with IF. Colonic eosinophilic inflammation is associated with clinical symptoms of GI blood loss, and peripheral eosinophilia, and was not abrogated by a strict elemental diet.

The challenges of managing and following-up a case of short bowel in eastern europe

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Long time hospital stay and cost are reduced by parental home care, while adequate hydration maintenance scheme is sine qua non.

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Inadequate monitoring system and lack of funding are two important factors that can influence morbidity and mortality.

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The immune deficient short bowel syndrome patient is always exposed to opportunistic life threatening infections.

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The lack of sufficient mucosal surface and long time intestinal adaptation process is crucial in determining bowel functional capacity.

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Intestinal stoma compared to primary anastomosis is debatable in short bowel syndrome surgery.

Introduction

This article reflects on the plight of patients with short bowel syndrome (SBS) in developing countries. SBS is life threatening, rare, complex and often not considered a priority by healthcare planners in the developing countries because of the high cost of treatment. Data was collected and analyzed from 3 different hospitals in two different countries (Romania and Austria) from November 2013 to February 2016

Case presentation

The patient had an emergency surgery for volvulus as a result of an extensive ischemic necrosis, with just 80 cm of the bowel left and no ileocecal valve after enterectomy. Despite intensive care and surgeries for anastomotic joint ischemic necrosis and intestinal adhesion with just 70 cm of the intestine left after primary anastomosis, the patient remained in a catabolic state (metabolic acidosis, severe malabsorption and loss of nutrients, water and electrolytes through diarrhea) and was transferred overseas where two more surgeries (intestinal stomas) and good intensive care helped to achieve enteral autonomy at the optimal time.

Discussion

This immune-deficient patient was exposed to various types of bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa). Two years after surgery an acute enterocolitis with salmonella infection and resultant intestinal failure treated in patient’s country of origin failed to achieve enteral nutrition warranting a second overseas transfer.

Conclusion

The lack of sufficient mucosal surface followed by long time intestinal adaptation process is crucial in determining bowel functional capacity. Long time hospital stay and cost was reduced through a parental home healthcare management training scheme.

Cholestasis in Preterm Infants

Cholestasis in preterm infants has a multifactorial etiology. Risk factors include degree of prematurity, lack of enteral feeding, intestinal injury, prolonged use of parenteral nutrition (PN), and sepsis. Soy-based parenteral lipid emulsions have been implicated in the pathophysiology of PN-associated liver injury. Inflammation plays an important role. Medical therapies are used; however, their effects have not consistently proven effective. Evaluation of cholestasis involves laboratory work; direct bilirubin levels are used for diagnosis and trending. Adverse outcomes include risk for hepatobiliary dysfunction, irreversible liver failure, and death. Early enteral feedings as tolerated is the best way to prevent and manage cholestasis.