Management of short bowel syndrome in children

INTRODUCTION — Short bowel syndrome (SBS) is a malabsorptive state that is caused by either massive resection of the small intestine or by a congenital defect or disease-associated loss of absorption. It is a functional definition, implying a significant amount of malabsorption of both macronutrients and micronutrients, rather than a definition based upon on the loss of a specific length or segment of bowel.

The gastrointestinal tract responds to massive resection with a process called intestinal adaptation, wherein changes in intestinal morphology and function gradually increase absorptive capacity. Through this process, many patients eventually are able to transition off of parenteral nutrition (PN) to full enteral feeds and some even achieve full oral feeding. During the past two decades, advances in medical and surgical management have resulted in reduced mortality, shorter duration of PN, and better weight gain for infants with SBS compared with previous cohorts [1,2]. Outcomes of SBS have also improved because of improvements in the prevention or management of the long-term complications, such as intestinal failure-associated liver disease (IFALD) and central venous catheter-associated bloodstream infections [3].

An overview of the management of pediatric patients with SBS is provided here. The pathogenesis of this disorder and the chronic complications of SBS are reviewed separately. (See "Pathophysiology of short bowel syndrome" and "Chronic complications of short bowel syndrome in children" and "Intestinal failure-associated liver disease in infants".)

DEFINITIONS

●Intestinal failure describes the state in which an individual's gastrointestinal function is inadequate to maintain nutrient, growth, and hydration status without intravenous or enteral supplementation [4,5]. This term is increasingly used in the literature to capture the broadest range of causes and includes short bowel syndrome (SBS), gastrointestinal dysmotility syndromes, and congenital disorders of enterocyte function. The American Society of Enteral and Parenteral Nutrition has proposed a definition of pediatric intestinal failure as a past or current history of "dependence on supplemental parenteral support for a minimum of 60 days within a 74-consecutive day interval" [6]. (See "Approach to chronic diarrhea in neonates and young infants (<6 months)".)

●Short bowel syndrome (SBS) describes intestinal failure that is caused by reduced small intestine mass due to massive resection, a congenital defect, or disease-associated loss of absorption. SBS is by far the most common cause of intestinal failure in infants and children.

●Enteral autonomy is the state in which the individual can survive and thrive without support from PN or intravenous fluids. Patients who achieve enteral autonomy may still require enteral tube feeding.

●Adaptation is the process following intestinal resection whereby the remaining bowel undergoes a range of morphologic and functional changes that increase its relative absorptive capacity. Adaptation is a critical step in achieving enteral autonomy. (See "Pathophysiology of short bowel syndrome", section on 'Intestinal adaptation'.)

EPIDEMIOLOGY — Estimates of the incidence and prevalence of SBS vary, in part because of differences in the case definition used across studies. Using a variety of definitions, the incidence of SBS has been estimated at approximately 0.02 to 0.1 percent among all live births [7,8], 0.5 to 2.0 percent among neonatal intensive care unit admissions [7,8], and 0.7 percent among very low birth weight infants [9]. Approximately 80 percent of pediatric SBS cases develop during the neonatal period.

The higher incidence of SBS among neonatal intensive care unit admissions and low birth weight infants is related to the proximate causes. Necrotizing enterocolitis is the most common cause of SBS in the neonate and is strongly associated with gestational age and birth weight [10]. (See "Neonatal necrotizing enterocolitis: Clinical features and diagnosis".)

PATHOPHYSIOLOGY

Causes — The most common causes of SBS in children were identified in a multicenter review from the Pediatric Intestinal Failure Consortium [11]:

●Necrotizing enterocolitis – 26 percent

●Gastroschisis – 16 percent

●Intestinal atresias – 10 percent

●Volvulus – 9 percent

●Long-segment Hirschsprung disease (aganglionosis) – 4 percent

●Other single or multiple diagnoses – 18 percent

In older age groups, resection due to trauma, Crohn disease, or cancer are more common causes of intestinal failure [1].

Predictors of enteral autonomy — A substantial portion of patients with SBS will be able to wean from parenteral nutrition (PN) and achieve enteral autonomy if given sufficient time and support to facilitate intestinal adaptation. The clinical course of SBS is strongly influenced by this process [12]. The changes include lengthening and dilatation of the bowel, lengthening of the villi and deepening of the crypts, increased synthesis of digestive enzymes, increased proliferation and apoptosis of enterocytes, and changes in gene expression [13,14]. The mechanisms and potential mediators of intestinal adaptation are discussed in detail in a separate topic review. (See "Pathophysiology of short bowel syndrome", section on 'Intestinal adaptation'.)

It is difficult to predict with certainty which patients will achieve enteral autonomy. The most consistently reported predictor of success is longer residual intestinal length [2,15]. Additional predictors of success reported in some studies include preservation of the ileocecal valve and underlying diagnosis of necrotizing enterocolitis rather than gastroschisis, atresias, or other causes of SBS [16-18]. In addition, several studies have reported a significant advantage of receiving care at a multidisciplinary intestinal failure center with an institutional philosophy that emphasizes rehabilitation and provides time and support to optimize intestinal adaptation, rather than an institutional philosophy that focuses on early referral to transplant [18,19]. (See 'Intestinal rehabilitation programs' below.)

●Length of remaining small intestine – The residual small intestine length measured immediately after resection is a moderately good predictor of whether a child will become independent from PN [18-20]. As an example, one study found that the cumulative probability of weaning from PN by 24 months was 96 percent in infants with >50 cm of residual small bowel versus 38 percent in those with <50 cm of residual small bowel [19]. However, reports vary regarding the amount of residual bowel associated with enteral autonomy due to difficulty with accurate assessment of intestinal length at the time of surgery, failure to account for premature birth, and the effect of other factors on the clinical course. While important, residual small intestine length should not be used as the sole predictor of whether the child will be able to achieve enteral autonomy. (See "Pathophysiology of short bowel syndrome", section on 'Small intestine length'.)

Residual small intestine length should be understood in the context of the expected intestinal length for the infant's gestational age. Small intestine length increases over the course of gestation and also for the first several years of life (figure 1). Thus, gestational age should be considered when evaluating residual small bowel length in premature infants. Small bowel length in infants and children during the first five years of life has been reported at a mean of 70 cm (standard error 6.3) at 24 to 26 weeks post-conception, 157.4 cm (standard error 11.2) at term, and 423.9 cm (standard error 5.9) at 49 to 60 months post-conception [21].

Despite a strong positive association between residual small bowel length and weaning from PN, there is substantial variation among individual patients and among institutions. Intestinal rehabilitation programs report successful achievement of enteral autonomy, even in patients with very short residual small intestine. One study reported that 48 percent of patients with <20 cm of residual small bowel achieved enteral autonomy, with a median time to PN independence of less than two years [22].

●Segments of remaining small intestine – The segment of remaining intestine helps determine the metabolic consequences of the SBS. In general, patients with an ileal remnant may have better outcomes than those with a jejunal remnant. (See "Pathophysiology of short bowel syndrome", section on 'Site of intestinal resection'.)

Retaining all or part of the ileum is advantageous for several reasons:

•Adaptation – Although the proximal small intestine is primarily responsible for the absorption of proteins, carbohydrates, and fats (figure 2), the ileum has a remarkable ability to adapt and compensate for absorption of these nutrients after loss of the jejunum. Unfortunately, the jejunum is not as efficient for nutrient absorption, nor able to adapt to compensate for the loss of the ileum.

•Fluid absorption – The ileum is uniquely structured to absorb fluids; patients lacking the ileum are particularly prone to watery diarrhea.

•Absorption of specific nutrients – The ileum is critical for absorption of vitamin B12 and bile salts. Individuals lacking the terminal ileum malabsorb bile salts, which in turn leads to malabsorption of fat and fat-soluble vitamins. They may have diarrhea, either due to direct effects of the malabsorbed bile salts in the colon (bile acid diarrhea) or due to insufficient bile salts for fat digestion, leading to fat malabsorption (steatorrhea). (See 'Common micronutrient deficiencies' below.)

•Gastric emptying – Unabsorbed lipids reaching the ileum delay gastric emptying, a function known as the "ileal brake." This delay in gastric emptying is considered beneficial because the slower release of gastric contents into the small intestine may enhance absorption.

•Ileocecal valve – Loss of the ileocecal valve is associated in some studies with reduced likelihood of achieving enteral autonomy and increased risk for complications of SBS, including small intestine bacterial overgrowth and malabsorption. However, it is unclear whether these associations are independently attributable to the loss of the ileocecal valve or whether they are mediated by the closely related factor of absence of the terminal ileum itself. (See "Pathophysiology of short bowel syndrome", section on 'Loss of the ileocecal valve'.)

●Presence of the colon – Loss of the colon reduces the likelihood of weaning from PN in adults with SBS, but the predictive value of this factor is less clear in children. Studies in infants and children have reached inconsistent conclusions about whether or not the presence of the colon in continuity is an important predictor of weaning from PN [16,17,22,23]. Our own clinical experience suggests that retention of all or part of the colon is beneficial for intestinal rehabilitation. (See "Pathophysiology of short bowel syndrome", section on 'Loss of the colon'.)

CLINICAL MANIFESTATIONS AND COMPLICATIONS — The type and severity of clinical manifestations of SBS vary widely among patients, even among those with similar etiologies and with roughly similar anatomic features. Depending on the patient's age, underlying diagnosis, and the quantity and location of affected bowel, patients with SBS may have any combination of the following problems:

●Excessive fluid and electrolyte losses

●Inability to absorb adequate energy and macronutrients (protein, carbohydrates, and/or fats)

●Inability to absorb necessary vitamins and minerals

●Poor weight gain/growth failure

●Intestinal dysmotility (particularly in patients with gastroschisis), dilatation, and stasis

Management of SBS addresses each of these problems, tailored to the individual's unique needs and clinical course.

In addition, patients with SBS are prone to a variety of gastrointestinal and extraintestinal complications, including intestinal failure-associated liver disease (IFALD), small intestine bacterial overgrowth, nutritional deficiencies, and feeding problems (table 1 and figure 3). (See "Chronic complications of short bowel syndrome in children".)

EARLY MANAGEMENT — During the first few months after intestinal resection, the predominant goals are maintenance of adequate nutritional status through administration of parenteral nutrition (PN) and prevention of fluid and electrolyte abnormalities [24]. Routine laboratory monitoring is essential for patients on PN and also during and after the transition to enteral feeds. A protocol for laboratory monitoring is outlined in the table (table 2). (See 'Laboratory monitoring' below.)

Parenteral nutrition — In this early phase, the major portion of energy is delivered through PN, but enteral nutrition should be initiated promptly to support intestinal adaptation [25-27]. The principles of prescribing PN to infants and children are discussed in detail in a separate topic review. (See "Parenteral nutrition in infants and children".)

Infants with SBS are at particular risk of developing intestinal failure-associated liver disease (IFALD). With careful management, many children with SBS can be weaned from PN before their native liver becomes irreversibly damaged. Important steps include maximizing enteral nutrition, limiting the dose of intravenous soy-based lipid emulsions, avoiding catheter-related bloodstream infections, and using alternative IV lipid formulations (such as fish oil-based monotherapy or mixed lipid emulsions). A detailed discussion of IFALD, including the possible role of the lipid emulsion in its pathogenesis and management and the potential benefit of fish oil-based lipid emulsions, is presented in a separate topic review. (See "Intestinal failure-associated liver disease in infants".)

Fluid management — Large-volume fluid losses from gastric or proximal small bowel secretions are common in the early phase. As a result, patients require vigorous replacement of fluids with sodium, potassium, chloride, and magnesium.

Fluid and electrolyte losses through an enterostomy or in the feces should be measured and replaced. The majority of chronic fluid replacement can usually be supplied through PN, using a solution that is tailored to the patient's fluid and electrolyte needs. Acute increases in enteral losses may warrant immediate replacement. This should be done with a solution separate from the PN to allow timely and accurate replacement of the losses. High-output ostomy or stool losses can also be replaced with appropriately formulated oral rehydration solutions as an adjunct to human milk or formula feeds. These solutions generally contain a suitably designed mix of water, electrolytes, and carbohydrate to replace diarrheal losses.

Acid suppression — Patients with SBS often exhibit hypersecretion of gastric acid and fluids, which reduces pH below the optimal level needed for fat absorption (by inactivating pancreatic lipase and deconjugating bile salts), increases intestinal fluid losses, and alters enteral drug absorption [28].

We routinely administer acid-suppressing medication during the early phase after intestinal resection to improve nutrient absorption and reduce fluid losses [29,30]. We typically start with an intravenous histamine 2 receptor antagonist (H2RA) to suppress gastric hypersecretion. If the medication appears to be effective in reducing fluid losses or improving absorption, acid suppression should be continued for several months. Use of an H2RA may lead to tachyphylaxis [31]; therefore, if symptoms are insufficiently controlled on an H2RA, a proton pump inhibitor (PPI) should be used. The gastric hypersecretion typically resolves during the first few months after surgery, and weaning of the acid-suppressing medications should be attempted a few months after the intestinal resection. Patients with persistent symptoms of gastroesophageal reflux and/or other forms of peptic disease may require longer courses of acid suppression therapy. (See 'Pharmacologic therapy' below and "Chronic complications of short bowel syndrome in children", section on 'Esophagitis/peptic ulcer disease'.)

Initiation of enteral feeds — Enteral feeds should be introduced as soon as the patient's condition stabilizes (often a few days after bowel resection) and advanced carefully but persistently, as rapidly as tolerated. The presence of nutrients in the intestinal lumen is essential to promote intestinal adaptation and appears to be more effective if enteral feeds are initiated early [32-34]. This effect occurs even when only small amounts of feeds are given (sometimes termed "trophic feeds"). Absence of enteral feeding may induce atrophy of the mucosa [35]. (See "Pathophysiology of short bowel syndrome", section on 'Nutrient effects'.)

●Diet composition

•Infants – Human milk should be used if possible. Human milk has the optimal macronutrient composition for infant growth, as well as trophic factors that may enhance intestinal adaptation and immunoglobulins and other immune factors that enhance mucosal barrier function [32,36-38]. In addition, human milk is relatively hypoallergenic. Human milk may also reduce the risk of developing IFALD, through an unclear mechanism [39]. Mothers of premature infants who require enteral feeds may need extra lactation support to optimize their milk production and milk expression. (See "Breast milk expression for the preterm infant".)

If human milk is not available or is not tolerated, use of an amino acid-based ("elemental") formula is appropriate. Amino acid-based formulas are preferable to standard cow's milk- or soy-based infant formulas because infants with SBS may more easily absorb nutrients that are broken down. The hypoallergenic nature of these formulas also may be beneficial because children with SBS may be at increased risk for protein allergy or intolerance [40-42]. However, amino acid-based formulas also have a high osmotic load compared with human milk, which may limit feeding tolerance. Factory closures, supply chain issues, and concerns about infectious complications of powdered formulas can also limit the availability of certain formulas [43]. (See "Chronic complications of short bowel syndrome in children", section on 'Allergic and eosinophilic disease' and "Overview of rickets in children", section on 'Phosphopenic rickets'.)

•Older children – If SBS first develops during childhood or adolescence, an intact protein or blenderized food formula may be trialed for initial enteral feeding because protein intolerance is less common in this age group compared with infants. Moreover, the complex nutrients that are found in intact protein formulas may be helpful in stimulating intestinal adaptation [44].

●Route of administration – For patients with SBS of all ages, enteral feeding is usually initiated as a continuous infusion via a nasogastric or gastrostomy feeding tube. Continuous enteral feeding maximizes tolerance in the setting of limited gut functional capacity [45]. It also saturates carrier transport proteins, taking full advantage of the absorptive surface area available and enhancing adaptation. Some patients, such as those with poor gastric emptying or intestinal dysmotility, may benefit from post-pyloric feeding using a gastrojejunal tube. (See "Overview of enteral nutrition in infants and children", section on 'Administration'.)

Regardless of the severity of SBS, it is imperative to provide small oral feedings at age-appropriate intervals to allow for development of suck and swallow reflex and to prevent oral aversion, even if only small volumes are tolerated. (See 'Oral feeding' below.)

ADVANCEMENT OF ENTERAL FEEDS — Maximizing enteral feeding is a central goal in the management of a patient with SBS. In addition to promoting intestinal adaptation, enteral feeding permits weaning off of parenteral nutrition (PN), which reduces the risk for complications of long-term PN, such as intestinal failure-associated liver disease (IFALD) and metabolic bone disease. (See "Intestinal failure-associated liver disease in infants" and 'Oral feeding' below.)

Protocol for feeding advancement — Enteral feedings should be advanced slowly but steadily, with reciprocal decreases in PN calculated to maintain nutritional status and compensate for fluid losses. The most successful approach is to make frequent small increases in enteral feeds as tolerated, with ongoing assessment of growth parameters to determine when PN can safely be reduced. The pace of feeding advancement depends upon the amount of remaining intestine, the patient's size and age, and the intestinal absorptive capacity. In most patients, the absorptive capacity gradually improves for several years after intestinal resection because of intestinal adaptation [11]. Speech/language pathologists are a beneficial addition to the multidisciplinary intestinal rehabilitation team to help guide and support oral feeding skills in parallel with advancing enteral feeds.

Estimating nutrient needs — The target for nutrient input should be guided primarily by serial measurements of weight and length. The goal is to achieve steady and proportional growth, assessed by comparing the infant's growth to standard growth curves for infants, with adjustment for premature birth until two years of age. In older children, additional factors, such as mid-parental height estimates, should be factored into expectations for growth.

Resting energy expenditure in infants with SBS is similar to that in healthy controls [46]. However, because of malabsorption, patients with SBS typically require 30 to 70 percent more calories if they are fed enterally compared with their energy needs from PN [47]. Therefore, the energy requirement (per kg) typically increases as enteral feeds are advanced and PN is decreased. (See "Measurement of growth in children", section on 'Recommended growth charts with calculators'.)

●Rate of feeding advancement – We recommend using a protocol with specific criteria to guide feeding advancement because this encourages steady progress [48]. For infants, our institutional practice is to initiate feeds early with human milk or amino acid-based formula and to increase enteral feeding volume by 10 mL per kg of body weight per day, as permitted based on stool or ostomy output. This protocol is summarized in the algorithm (algorithm 1 and table 3) [34].

The protocol assumes that the following criteria represent a threshold for enteral tolerance:

•Enteral fluid loss – 2 to 3 mL/kg/hour of ostomy output or 10 to 20 g/kg/day of stool output are used as the primary indicators that the threshold of enteral tolerance has been reached

•Reducing substances – 1 percent in stool or ostomy output may be used as a secondary indicator that the threshold of enteral tolerance has been reached

Enteral fluid losses less than these thresholds warrant continued modest advancement in the rate of enteral feeds. Values above this threshold indicate that enteral tolerance has been exceeded and warrants interruption of the enteral feeds and/or a modest reduction in the feeding rate.

These thresholds are approximate, and individual patients may tolerate a faster or slower pace of feeding advancement. The benefits of a similar feeding advancement protocol was shown in a series from a large neonatal intensive care unit, in which meaningful advances in enteral feeds were achieved more rapidly and the risk of IFALD was substantially reduced when specific advancement criteria were used [48].

Stool alpha-1 antitrypsin, fecal elastase, and spot tests for fecal fat generally should not be used to judge enteral feeding tolerance, because they are frequently abnormal in SBS even when the child is otherwise tolerating enteral feeds. However, these tests may be helpful to guide decision-making about clinical monitoring and formula selection. For example, a patient with steatorrhea may benefit from a medium-chain triglyceride (MCT)-enriched formula and is also at increased risk for developing fat-soluble vitamin deficiencies. (See 'Diet composition and adjustments' below.)

●Weaning PN – The amount of PN provided must be individualized, with the goal of providing the minimum amount of PN required to sustain a normal growth pattern and body composition. Indications for continued PN include poor weight gain or fluid and electrolyte losses that are too extensive to be replaced enterally. Some patients are eventually able to wean from PN but continue to need parenteral fluids to prevent dehydration and electrolyte imbalance, which are typically administered at night for convenience. A reasonable approach is to focus first on weaning PN and then on weaning intravenous fluid support.

In some patients, feeding tolerance may continue to improve over several years as intestinal adaptation progresses, ultimately allowing a gradual conversion to a full enteral diet [49]. Some children with borderline enteral function can be maintained with a regimen of PN fewer than seven nights per week. It is important to note that these patients might be at increased risk for vitamin and micronutrient deficiency, and therefore, those patients receiving fewer than seven nights per week of PN should also receive a daily enteral vitamin supplement (see 'Common micronutrient deficiencies' below). Children often require significant increases in PN during puberty to support this phase of rapid growth. (See "Parenteral nutrition in infants and children", section on 'How to prescribe parenteral nutrition'.)

PN "cycling" refers to the technique of administering the same total volume of PN solution at a higher rate for fewer than 24 hours, thereby providing a period of time each day without PN infusion. This approach is valuable as patients become older and better able to tolerate enteral nutrition. It provides the patient with greater freedom, helps to promote an interest in oral feeds, and may reduce the hepatotoxic effects of the PN (IFALD) [50,51]. PN cycling requires careful planning and monitoring to avoid hyperglycemia and hypoglycemia. The technique and monitoring are discussed separately. (See "Parenteral nutrition in infants and children", section on 'Cycling'.)

Diet composition and adjustments — For infants, feeding with human milk is preferred, as discussed above. If human milk is not available or is poorly tolerated, we change to an amino-acid based formula, which is typically continued throughout infancy. (See 'Initiation of enteral feeds' above.)

For children who had SBS during infancy and were fed human milk or an amino acid-based formula, it may be possible to transition to an intact protein formula or blenderized food formula sometime during the second year of life. This decision is patient-specific, and a transition is often initiated when the child begins to take increasing amounts of intact protein by mouth in the form of table foods. In some cases, it is useful to transition to a partially hydrolyzed formula rather than one composed of intact proteins. The approach to transitioning should be gradual, and some patients continue to require an amino acid-based formula. Patients who develop clinical symptoms (diarrhea, vomiting, or poor weight gain) or endoscopic/histologic abnormalities following a change to intact protein formula may need to resume an amino acid-based diet.

For patients with specific nutritional challenges or who are not making progress in advancing feeds, additional adjustments to the macronutrient content of the diet may be helpful, as outlined below. These considerations are also relevant for toddlers or older children who are transitioning from enteral feeds to an oral diet.

●Fats – Infants and young children with SBS generally benefit from a relatively high-fat enteral diet, in which fat comprises 40 to 50 percent of total enteral energy intake [52]. Dietary fat has the benefit of a relatively low osmotic load and a high energy content and may also promote intestinal adaptation and improve enteral tolerance [53,54]. (See "Pathophysiology of short bowel syndrome", section on 'Nutrient effects'.)

For infants, human milk and standard infant formulas have fat contents within the target range. However, when patients begin to transition to an oral diet, we encourage foods that are high in fat if tolerated. Strategies to incorporate more fat into the oral diet include using additional oil and butter while cooking.

For a toddler or older child, it is useful to consider the content of both long-chain triglycerides (LCTs) and MCTs in the composition of a formula. LCTs may be helpful in stimulating bowel adaptation, and MCTs may be better absorbed since they directly cross the enterocyte membrane and thus bypass the need for lymphatic absorption. A ratio of 40 percent MCTs to 60 percent LCTs has been suggested for patients with SBS; however, the proportion should be adjusted based on the individual patient's response to different feeds [55]. (See "Pathophysiology of short bowel syndrome", section on 'Nutrient effects'.)

Patients with intestinal failure are at risk for essential fatty acid deficiency (as defined by a triene:tetraene ratio >0.05), particularly during or shortly after weaning from PN. Therefore, laboratory testing for essential fatty acid deficiency should be performed for all patients one to two months after weaning from PN and every 12 months thereafter or if clinical suspicion for essential fatty acid deficiency exists. Signs and symptoms of essential fatty acid deficiency include dry scaly rash, poor growth, thrombocytopenia, poor wound healing, and increased susceptibility to infections.

If the triene:tetraene ratio indicates essential fatty acid deficiency, the diet should be supplemented with oils that are high in essential fatty acids (canola, walnut, or flaxseed oils), along with ongoing monitoring for essential fatty acid deficiency and growth. (See "Chronic complications of short bowel syndrome in children", section on 'Common deficiencies'.)

●Carbohydrates – Limiting carbohydrate intake is part of the routine management of SBS because most affected infants, and especially those without a colon, do not tolerate high concentrations of carbohydrates. This is because carbohydrates tend to have an increased osmotic load compared with fats and intact proteins. Complex carbohydrates have a lower osmotic load than simple carbohydrates (sugars) and, therefore, may be better tolerated.

The individual patient's anatomy and response to feeding should guide any dietary restrictions. For infants on formula feeds, the strategies to manage carbohydrate intolerance include slow advancement of feeds and selection of formula with a higher fat content. For older patients, strategies include selection of formulas or solid foods with starches or other complex carbohydrates (eg, blenderized formulas) rather than high concentrations of simple sugars.

Lactose should not be automatically restricted for patients with SBS, although it may be poorly tolerated by a subset of patients. Dairy products are a good source of fat, energy, and calcium. Cheese or yogurt may be better tolerated than milk [56]. Therefore, it is typical to introduce yogurt or cheese initially and then broaden the diet to include milk if the patient shows no signs intolerance or allergy.

●Fiber – Increasing dietary fiber improves the diarrhea for some patients; the first step is to add solid foods that are rich in fiber, such as green beans [57,58]. For selected patients, soluble fibers such as pectin or guar gum may be used to help manage watery diarrhea. Candidates for fiber supplements are older infants or children with watery diarrhea that is problematic and does not respond to carbohydrate restriction and who have an intact colon and no history or risk factors for small intestine bacterial overgrowth. (See "Chronic complications of short bowel syndrome in children", section on 'Pharmacotherapy'.)

●Oxalate – Children with SBS who have developed calcium oxalate renal stones or symptomatic D-lactic acidosis (a sequela of certain types of small intestine bacterial overgrowth) should be managed with a low-oxalate diet. Typically, this is achieved through avoidance of table foods that are high in oxalate rather than changing the type of enteral formula. Foods high in oxalate include rhubarb, spinach, beets, potatoes, and cocoa [59].

Calcium oxalate renal stones in patients with SBS are related to fat malabsorption because fat binds of free calcium acids in the intestinal lumen, which interfere with calcium binding to oxalate, resulting in hyperoxaluria. In patients with a history of D-lactic acidosis, a low-oxalate diet may be indicated to avoid inhibition of the D2-hydroxy-acid dehydrogenase (D-2HDH) enzyme and thus promote adequate metabolism of D-lactic acid to prevent this complication [60]. (See "Chronic complications of short bowel syndrome in children", section on 'Small intestinal bacterial overgrowth' and "Chronic complications of short bowel syndrome in children", section on 'Hyperoxaluria and kidney stones'.)

Laboratory monitoring — Routine laboratory monitoring is essential for patients on PN and also during and after the transition to enteral feeds. A protocol for laboratory monitoring is outlined in the table (table 2); this reflects common practice in centers with experience in managing SBS in children, based on expert opinion and clinical experience [61].

In addition to routine laboratory monitoring, we monitor urine sodium levels in infants and children with high ostomy or stool output, especially in those with poor growth despite adequate calorie intake. The goal is to maintain urine sodium concentrations >20 mEq/L [61]. Low levels of total body sodium can contribute to poor growth and may not be reflected in measures of serum sodium, which often remain normal (despite total body depletion) due to renin and aldosterone-mediated renal conservation [62]. If the urine sodium concentration is low, sodium supplements may be added to enteral feeds or increased by using sodium-containing oral rehydration solutions to maintain sodium intake. Interpretation of urine sodium levels is challenging in patients with cirrhosis-induced hyperaldosteronism and/or those who use loop diuretics, which alter renal sodium kinetics [62].

CONVERTING TO BOLUS FEEDS — As tolerance improves, continuous feedings may eventually be either partially or completely replaced by intermittent bolus feedings. A common approach is to initiate bolus feeds when a patient is receiving at least one-half of his or her total energy requirements from enteral feeds, with the remainder coming from parenteral nutrition (PN) [63]. For convenience, patients may receive continuous enteral feeds at night and bolus feedings during the day. Generally, small, frequent bolus or oral feedings are better tolerated than infrequent, large feedings. In an animal model, bolus feedings were associated with better markers of intestinal adaptation [64] and are associated with cyclical release of gastrointestinal hormones. These observations suggest that there may be good reasons to use both continuous and bolus feedings in the management of SBS.

ORAL FEEDING

●Infants – Early initiation and persistent administration of feeds through the oral route is important to help prevent the development of feeding aversion. Feeding aversion is common unless oral feeds are provided at the developmentally appropriate times and can become a chronic problem. Recommendations for most infants, based on expert opinion and experience, are as follows [61,63]:

•Introduce small oral feeds of human milk or formula during the neonatal period or as soon as enteral feeds are tolerated. A common initial approach is to give an oral feed two to three times per day, replacing one hour of the infant's continuous enteral feedings [63].

•Introduce solid foods at an appropriate age (eg, between four and six months corrected gestational age), provided oromotor function is adequate and safe [63]. At our center, we typically start with rice cereal or finely pureed fruit or vegetable. Some other centers start by introducing a pureed meat due to the high protein, iron, and fat content and the relatively low carbohydrate load. Regardless of the food, it is important to be vigilant for signs of poor tolerance, such as increased gastrointestinal output, or allergy, such as rash or bloody stools. Families and caregivers should be counseled to introduce only one new food per week to allow for accurate assessment of tolerance. Children with SBS have a higher risk for food allergies due to impaired intestinal barrier and absorptive functions. Fruit and foods with high sugar content should generally be avoided because they may promote small intestine bacterial overgrowth. (See "Chronic complications of short bowel syndrome in children", section on 'Allergic and eosinophilic disease' and "Chronic complications of short bowel syndrome in children", section on 'Small intestinal bacterial overgrowth'.)

●Children – Children who successfully wean from parenteral nutrition (PN) are often able to gradually transition from tube feeding to oral feeding and may eventually achieve a fairly normal diet. These children tend to tolerate fats better than carbohydrates and complex carbohydrates better than simple sugars. Hyperphagia is a typical and expected response as a means of overcoming malabsorption. However, incorrect choices of oral foods may lead to higher gastrointestinal outputs and regression of enteral autonomy. Routine counseling with a dietitian is helpful to mitigate this risk.

Especially after achieving an ad libitum oral diet, children with SBS may experience fat malabsorption. This finding does not typically warrant a reduction in the intake of dietary fat, because the energy density of fat is twice that of protein and, thus, it provides significant energy even if partially malabsorbed.

The important elements of chronic enteral nutrition are:

•A diet that is a reasonably balanced mixture of fats, protein, and carbohydrates

•Avoidance of hypertonic beverages (eg, sodas and fruit juices) and simple carbohydrates

•Introduction of oral feeding at age-appropriate intervals to promote suck and swallow reflex and to prevent oral aversion

•Monitoring and replacement therapy for micronutrient deficiencies (see 'Common micronutrient deficiencies' below)

●Oral aversion – Many children with SBS have poor appetite and/or oral aversion, which impede the transition to oral feeding. For those with poor appetite, cyproheptadine may be useful for its appetite-stimulating effects, which may be helpful during a transition to oral feeding. Children with oral aversion should be referred to a feeding therapist or other behavioral specialist. Most children with SBS benefit from routine follow-up with a feeding therapist from an early age. (See "Chronic complications of short bowel syndrome in children", section on 'Feeding problems and oral aversion'.)

VITAMIN AND MINERAL SUPPLEMENTATION — Children with SBS are at substantial risk for nutritional deficiencies, particularly while parenteral nutrition (PN) is being weaned and after it is discontinued.

Common micronutrient deficiencies — Deficiencies of fat-soluble vitamins (A, D, E, and K), iron, vitamin B12, copper, selenium, iodine, and zinc can be seen in SBS [65]. The magnitude of risk and type of deficiency depends in part on which section of the bowel was resected (figure 2). Micronutrient deficiencies may occur even if the total energy absorption and somatic growth are adequate [66]. Routine laboratory screening and supplementation are important for prevention, detection, and appropriate treatment of these common deficiencies; a schedule is outlined in the table (table 2).

The risk of nutrient deficiency is greatest after discontinuation of PN because the degree of intestinal adaptation and the absorption of nutrients are unpredictable [65]. However, patients on full PN support also may have deficiencies and should be monitored. For example, the frequency of vitamin D deficiency has been reported as 40 percent in a group of patients on home PN, with a large portion of that cohort showing radiographic evidence of osteopenia [67]. Risk factors and clinical manifestations of these deficiencies are discussed in more detail elsewhere. (See "Chronic complications of short bowel syndrome in children", section on 'Nutritional complications'.)

Routine vitamin supplements — In our program, we routinely initiate an oral or enteral multivitamin supplement when PN (and thus parenteral multivitamin intake) is weaned to fewer than seven days per week. Due to fat malabsorption associated with SBS, we use a supplement with water-miscible forms of the fat-soluble vitamins (eg, DEKAs, GenADEK, and others). DEKAs does not contain copper; if copper deficiency is detected, it may be necessary to add an additional complete multivitamin containing copper (or a separate copper supplement). In such cases, routine laboratory testing is important to screen for hypervitaminosis.

Treatment of identified deficiencies — Patients with identified deficiencies require additional supplementation and monitoring. Vitamin B12 deficiency is particularly common in SBS in children with a history of terminal ileum resection who have been weaned from PN. The approach to treatment is discussed separately. (See "Chronic complications of short bowel syndrome in children", section on 'Common deficiencies'.)

ADDITIONAL STRATEGIES FOR REFRACTORY CASES

Pharmacologic therapy — Administration of any medication via the enteral route to an individual with SBS requires attention to dosing because absorption and pharmacokinetics are often abnormal. A variety of factors may affect the pharmacokinetics of enterally administered medications, including the extent and function of remaining bowel, the presence (or absence) of terminal ileum, and the pH of the gastrointestinal tract [68]. In some situations, such as the provision of antibiotic therapy for acute infection, parenteral routes of administration may be required due to impaired intestinal absorption of enteral medications. In other cases, such as with many vitamin supplements, higher-than-expected doses must be used to overcome intestinal malabsorption and achieve therapeutic effects.

Medications that are used to address the specific symptoms and complications of SBS are outlined in the table (table 4) and summarized below.

●Watery diarrhea – Watery diarrhea is the most common early complication of SBS in children and may also be a chronic or recurrent problem. In addition to fluid and electrolyte replacement and dietary modification, management often includes the use of these medications:

•Loperamide – Loperamide is an antimotility agent that is often helpful for managing watery stool; however, it should be used with caution as it may exacerbate small intestine bacterial overgrowth in patients with bowel dilatation or concurrent gastrointestinal dysmotility.

•Cholestyramine – Cholestyramine may be appropriate for patients with diarrhea following extensive resection of the distal ileum. The diarrhea in these patients may be caused by malabsorbed bile acids entering the colon (bile acid diarrhea), and cholestyramine prevents this process by sequestering bile acids. However, bile acid sequestrants should be used with caution because they may impair fat-soluble vitamin absorption and cause gastrointestinal irritation [62]. Bile acid sequestrants have no effect on diarrhea caused by carbohydrate malabsorption, which is another common cause of diarrhea in SBS.

•Pancreatic enzymes – Although evidence supporting the use of pancreatic enzyme replacement therapy is relatively weak [69], a trial of pancreatic enzyme replacement therapy may be appropriate for rare patients with suspected pancreatic insufficiency, identified by marked steatorrhea or clinical risk factors. Of note, testing for pancreatic insufficiency by measuring fecal elastase may be inaccurate in patients with SBS because the result can be falsely low (false-positive test). Steatorrhea in SBS is usually caused by mucosal malabsorption rather than pancreatic insufficiency.

•Octreotide – Octreotide may be useful for patients with very high stool output and/or dysmotility (eg, high-output ostomy) who fail the dietary and other pharmacologic measures described above [70]. Potential adverse effects include hindrance of intestinal adaptation, growth delay, and increased risk for gallstones and pancreatitis. (See "Management of short bowel syndrome in adults", section on 'Octreotide'.)

Management of chronic diarrhea and use of the above medications are discussed in more detail in a separate topic review. (See "Chronic complications of short bowel syndrome in children", section on 'Chronic diarrhea'.)

●Persistent intestinal failure – Teduglutide (Gattex, Revestive) can be used to promote intestinal adaptation in patients who remain dependent on parenteral nutrition (PN) and/or intravenous fluids for more than one year after a major intestinal resection. In 2019, it was approved for this use in the United States for children >1 year of age; it is given once daily as a subcutaneous injection. This medication should be used in the context of a specialized intestinal rehabilitation program and with close follow-up to allow PN weaning if indicated and to screen for adverse effects. Available evidence suggests that teduglutide enhances intestinal adaptation, but the data are insufficient to precisely identify which patients would benefit most from treatment.

Teduglutide is an analog of glucagon-like peptide 2 (GLP-2), which is an enteroendocrine peptide released in response to luminal nutrients. Several studies in animals demonstrate that GLP-2 initiates and maintains the small bowel adaptive response to resection [71]. Assorted functions of GLP-2 stimulate intestinal mucosal crypt cell proliferation, leading to increased villus height, intestinal length, and surface area for fluid and nutrient absorption [55].

Studies in adults with SBS have shown that teduglutide positively affects absorption of both fluids and nutrients and is associated with a commensurate reduction in PN dependence when given daily as a subcutaneous injection [72-74]. In an open-label study in PN-dependent children with SBS, treatment with teduglutide for 24 weeks was associated with significant reduction in PN requirements compared with untreated children and was well tolerated [75]. A separate study reported that 12 of 17 patients achieved PN independence within one year of drug therapy (although the report did not describe optimization of medical care before the start of teduglutide) [76]. A follow-up study is being performed (NCT04832087) to determine long-term risks and benefits of treatment with teduglutide in children.

The incidence of adverse events during treatment with teduglutide is similar to placebo, with the exception of abdominal pain, which was reported more frequently in the teduglutide groups [75]. In long-term follow up (median one year), abdominal pain and vomiting were each experienced by approximately 5 percent of patients [77]. Since teduglutide enhances mucosal proliferation, colonoscopy should be considered before starting teduglutide to screen for polyps, and patients with a history of gastrointestinal neoplasms should not use this medication. Patients on teduglutide for one year or more should also undergo a screening colonoscopy and regular occult fecal blood testing.

Trials of longer-acting GLP-2 analogs (eg, apraglutide, glepaglutide) have shown promise in adults [78,79]; data in children are awaited.

Other trophic agents that have been evaluated to enhance intestinal adaptation include glutamine and growth hormone, but neither have been shown to be efficacious [80-84].

●Enteritis – Children with SBS are at risk for chronic gastrointestinal inflammation, possibly related to the combination of dysmotility, bowel dilatation, small bowel bacterial overgrowth (SBBO), and ischemia. We commonly use intermittent courses of antibiotics to treat or prevent SBBO, and preliminary data support this approach to improve growth and reduce symptoms [85]. Common regimens include metronidazole, ciprofloxacin, amoxicillin-clavulanic acid, gentamicin, and others, selected based on the patient's history and symptomatic response. (See "Chronic complications of short bowel syndrome in children", section on 'Small intestinal bacterial overgrowth'.)

Anastomotic ulcers can sometimes resemble idiopathic inflammatory bowel disease, and case reports describe treatment with antiinflammatory medicines including aminosalicylate preparations, steroids, and even tumor necrosis factor-alpha-blocking agents [86]. (See "Chronic complications of short bowel syndrome in children", section on 'Inflammatory bowel disease–like syndrome'.)

Intestinal rehabilitation programs — Benefits of managing SBS in an intestinal rehabilitation program have been established in numerous reports. These programs convene a multidisciplinary team of experts in a center specializing in SBS and focus on optimizing enteral feeding and weaning from PN, with judicious use of pharmacotherapy and surgical interventions. This approach is associated with improved survival and achievement of independence from PN [22,87-90]. Clinical guidelines from the American Society for Parenteral and Enteral Nutrition suggest that for patients managed by multidisciplinary teams, the "improvement in survival is compelling" [91]. Management of SBS patients by, or in consultation with, intestinal rehabilitation centers is also endorsed by the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition [92].

Surgical interventions

Intestinal lengthening procedures — A number of surgical procedures have been designed for children with intestinal failure and are sometimes termed "autologous intestinal reconstruction surgery" (AIRS) [93]. Methods focus on surgical lengthening of the bowel to increase the absorptive area as well as tapering or plicating the dilated bowel to improve motility [87,88]. The relative contributions of the medical as compared with the surgical interventions in children with intestinal failure have not been well established or prospectively determined. The decision to pursue surgical intervention should be weighed on a case-by-case basis against the likelihood of eventually weaning the patient from PN using nonoperative therapies, ideally administered in the setting of an intestinal rehabilitation program. (See 'Intestinal rehabilitation programs' above.)

●Indications – Candidates for AIRS in patients with intestinal failure generally meet the following criteria [94,95]:

•Dilated small intestine.

•Failure to progress towards enteral autonomy using standard medical and nutritional strategies, ideally administered in an intestinal rehabilitation program. This criterion is difficult to judge since progress towards enteral autonomy can be slow.

•Absence of serious comorbidities that would preclude major surgery (including advanced liver disease).

•Adequate bowel length anticipated after AIRS (to likely allow the achievement of enteral autonomy).

•Absence of a preexisting gastrointestinal motility disorder.

Additional indications for AIRS may include congenital intestinal atresia with dilated proximal bowel and marginal intestinal length, as well as refractory small intestine bacterial overgrowth.

●Techniques – Two AIRS procedures are used to increase bowel length and absorptive area [96]:

•STEP procedure – The serial transverse enteroplasty procedure (STEP) (figure 4) is simpler and more flexible than prior intestinal lengthening procedures, including the Bianchi procedure described below. No bowel anastomoses are created, and the tapering can be performed on variably dilated bowel. STEP increases intestinal length, improves intestinal absorptive capacity, and may decrease the risk of D-lactic acidosis due to small intestine bacterial overgrowth [97-100]. It can be performed alone or after a prior Bianchi procedure. No prospective comparison of medical versus surgical therapy for SBS has been performed. Thus, the independent effect of the STEP itself on PN wean has not been established.

In a report from a large registry of patients who underwent STEP (n = 97), predictors of achieving enteral autonomy were longer pre-STEP bowel length and less severe cholestasis [101]. Nearly one-half of patients undergoing STEP due to SBS achieved enteral autonomy; the median time to wean from PN was 21 months postoperatively.

STEP can be repeated to further increase intestinal length [94,102]. Patients who have renewed bowel dilation after a lengthening procedure have worse overall outcomes compared with those without bowel dilation [103]. Complications of STEP and of other bowel-lengthening procedures include gastrointestinal bleeding (most common), stricture, and obstruction [104].

•Bianchi procedure – The Bianchi procedure (figure 5), also known as longitudinal intestinal lengthening and tailoring (LILT), was one of the first surgical approaches used to lengthen the intestine [105]. This procedure is generally thought to be successful in improving absorption and nutritional status but requires multiple anastomoses, has the potential to compromise intestinal blood flow, and cannot be performed on segments of intestine with variable dilatation.

Small bowel transplantation — The need for small bowel/multivisceral transplantation in patients with SBS has decreased as outcomes from medical and surgical management have improved. The number of intestinal transplantations in the United States declined by 25 percent between 2006 and 2012 [106].

Selected children with SBS are transplantation candidates; these include patients with progressive and severe intestinal failure-associated liver disease (IFALD), loss of venous access, or recurrent life-threatening central venous catheter-associated bloodstream infections [107]. Additional indications include complete mesenteric thrombosis, slow-growing tumors of the hepatic hilum or root of mesentery, or extremely short residual bowel (ie, little to no chance of achieving enteral autonomy) in a patient who prefers transplantation to lifelong PN dependence. (See "Overview of intestinal and multivisceral transplantation".)

OUTCOMES

●Growth – Infants and children with SBS often have growth failure. In one study, 46 percent of patients had a height-for-age Z-score of less than -2 and higher rates of growth failure were seen in those with secondary enteropathy or intestinal inflammation [108]. Another series examined long-term growth outcomes in 31 children with a history of SBS as infants [109]. At mean age 11.8 years (standard deviation 4.2 years), affected individuals had slightly shorter stature than was expected from calculated target height and their bone mineral content was lower than reference values. However, the children had normal body fat percentage and normal weight-for-height ratios. A third study of 51 infants with SBS showed a "U-shaped curve" for both weight-for-age and length-for-age Z-scores over the first year of life, with a nadir at approximately six months (-2.38 and -2.18, respectively) and near recovery by one year (-0.72 and -0.76, respectively). Inflammatory conditions such as central venous catheter-associated bloodstream infections and necrotizing enterocolitis were associated with lower scores on both of these indices of growth [110]. Of note, patients managed with a fish oil-based lipid emulsion due to cholestatic liver disease can achieve normal growth [111].

Although these and other studies suggest that long-term parenteral nutrition (PN) dependence has modest effects on linear growth, many patients achieve normal height. This suggests that secondary factors may contribute to the growth failure observed in some patients, such as intestinal inflammation, corticosteroid use, and/or aggressive weaning of PN to avoid chronic complications.

●Enteral autonomy – The prognosis for achieving enteral autonomy depends in part on patient factors such as intestinal length and remaining segments, with substantial individual variation. Even patients with extremely short bowel (eg, infants with <20 cm) are able to achieve enteral autonomy in approximately one-half of cases, when optimally treated and with access to an intestinal rehabilitation program. (See 'Predictors of enteral autonomy' above.)

●Mortality – Estimated mortality rates for infants and children with SBS vary substantially both between institutions and over time. A report representing the collective experience of 14 pediatric centers in North America between 2000 and 2007 describes a mortality rate of 27 percent, an intestinal transplant rate of 26 percent, and an enteral autonomy achievement rate of 47 percent [11]. A report from 2010 to 2015 from Canada, New Zealand, and the United Kingdom with six years of follow-up describes a mortality rate of 10.5 percent and an enteral autonomy rate of 53 percent [112]. Improvements in SBS survival have been described over time, with mortality rates falling from 20 to 40 percent to 10 percent or less in more recent studies [113-115]. Predictors of survival vary among studies but include enteral autonomy (PN independence), participation in a multidisciplinary intestinal rehabilitation program, longer residual bowel length, and lower direct bilirubin levels [114,115]. PN dependence remains the most important risk factor for potentially fatal complications of SBS including intestinal failure-associated liver disease (IFALD) and sepsis. Therefore, optimal management of SBS to reduce the need for PN is essential. (See "Intestinal failure-associated liver disease in infants".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Short bowel syndrome" and "Society guideline links: Nutrition support (parenteral and enteral nutrition) for neonates including preterm infants" and "Society guideline links: Nutrition support (parenteral and enteral nutrition) in infants and children".)

SUMMARY AND RECOMMENDATIONS

●Goals – Goals for managing short bowel syndrome (SBS) are to attain appropriate growth, minimize complications including intestinal failure-associated liver disease (IFALD) (figure 3), and achieve enteral autonomy. (See 'Clinical manifestations and complications' above and "Chronic complications of short bowel syndrome in children".)

●Pathophysiology – The primary factors that influence the likelihood that a patient with SBS will ultimately be able to wean from PN are the length of remaining small bowel, which segments of the bowel remain, and the process of intestinal adaptation. Intestinal adaptation occurs gradually and requires exposure of the intestine to enteral feeds. (See 'Predictors of enteral autonomy' above.)

●Initial management – Early management of SBS involves close monitoring of stool output and replacement of these fluid and electrolyte losses. PN is used for nutritional support. (See 'Early management' above.)

•Enteral feeding – Enteral feeding should begin promptly once the patient stabilizes after intestinal surgery; a protocol for initiating and advancing feeds and guiding principles are summarized in the algorithm and table (algorithm 1 and table 3).

-Continuous enteral feeding or small, frequent feedings are preferred initially. For infants, human milk or amino acid-based formulas are preferred. (See 'Initiation of enteral feeds' above.)

-The absorptive state and feeding tolerance are reassessed frequently as adaptation progresses, mostly based on changes in stool output, and the composition and rate of enteral feeds is adjusted accordingly. The overall goal is to maximize the proportion of nutrition given via the enteral route, as tolerated. (See 'Protocol for feeding advancement' above.)

•Acid suppression – We recommend administering acid-suppressing medications (histamine 2 receptor antagonists [H2RAs] and proton pump inhibitors [PPIs]) to patients with SBS during the first three to six months after intestinal resection to reduce gastric secretion and enteral fluid losses (Grade 1B). (See 'Acid suppression' above and 'Pharmacologic therapy' above.)

●Vitamin and mineral deficiencies – Children with SBS are at substantial risk for nutritional deficiencies, particularly while PN is being tapered and after it is discontinued. Deficiencies may include fat-soluble vitamins (A, D, E, and K), calcium, iron, copper, and vitamin B12. Our practice is to initiate an enteral vitamin supplement when PN has been weaned to fewer than seven days per week, using a water-miscible form of vitamins A, D, E, and K. We perform routine laboratory testing for vitamin and mineral deficiencies before and after weaning from PN (table 2) and provide additional supplements as needed. (See 'Laboratory monitoring' above and 'Vitamin and mineral supplementation' above.)

●Additional strategies for refractory cases

•Pharmacotherapy – Several medications have been tested in an effort to enhance intestinal adaptation and improve feeding tolerance (table 4):

-Loperamide and cholestyramine are often useful to maximize enteral tolerance in select SBS patients. Other medications are occasionally used to promote motility or stimulate appetite, based on limited evidence. (See 'Pharmacologic therapy' above and "Chronic complications of short bowel syndrome in children", section on 'Pharmacotherapy'.)

-Teduglutide, an analog of glucagon-like peptide 2 (GLP-2), has benefits in promoting intestinal adaptation in SBS and may be considered for children with persistent intestinal failure, as part of a comprehensive intestinal rehabilitation program. (See 'Pharmacologic therapy' above.)

•Intestinal rehabilitation program – Management of SBS patients in a multidisciplinary intestinal rehabilitation program has led to improved survival, higher rates of weaning from PN, and other important outcomes. (See 'Intestinal rehabilitation programs' above.)

•Surgery – In patients with dilated bowel who are not making significant progress towards weaning from PN despite maximal medical and nutritional therapy, an intestinal lengthening procedure may be helpful. (See 'Intestinal lengthening procedures' above.)

•Transplantation – Small bowel or multivisceral transplantation is appropriate for selected individuals with life-threatening complications of SBS. Because of the success of multidisciplinary intestinal rehabilitation programs, the need for intestinal transplantation for SBS has diminished substantially. (See 'Small bowel transplantation' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Jon A Vanderhoof, MD, and Rosemary J Pauley-Hunter, NP-C, MS, RN, who contributed to earlier versions of this topic review.