Short bowel syndrome (SBS) is a malabsorptive condition that is most often caused by a massive resection of the small intestine [52]. Its prevalence is 3–4 per million [53] and occurs in about 15% of adult patients undergoing an intestinal resection, either massive (3/4) or from multiple sequential resections (1/4) [54]. Although its causes may be diverse, in the present manuscript, we will refer to the one that results from a massive bowel resection [55]. SBS and intestinal failure (IF) are not necessarily synonymous. Intestinal failure describes the state when an individual’s gastrointestinal function is inadequate to maintain his or her nutrient and hydration status without intravenous or enteral supplementation [56,57,58].
Complications Related to SBS | Pathogenesis |
---|---|
(I) Complications related to SBS pathophysiology and its underlying pathology | The pattern of nutrient absorption native to the parts of the gastrointestinal tract is shown in Figure 1. |
Peptic ulcer | Hypergastrinemia resulting from a failure of enterogastrone release (e.g., VIP, GIP, neurotensin, peptide YY, and GLP-1). Treatment with antisecretory drugs could also aggravate SIBO due to hipoclorhydria [73]. |
Electrolyte disturbances: hypocalcemia, hypokalemia, and hypomagnesemia |
Occur especially when large-volume diarrhea is present. (e.g., associated with an end jejunostomy). |
D-lactic acidosis (D-LA) | The SBS microbiota, since it is rich in Lactobacillus, leads to the accumulation of fecal lactate. Lactate does not accumulate in healthy human feces because it is absorbed by intestinal cells, but in some SBS patients, the high amount of lactate found in feces indicates that production exceeds absorption capacities by the host. Excess lactate released into the colon is fermented by bacteria and converted into D-lactate, which has neuro-toxic effects [67,68,69]. |
Cholelithiasis | In the presence of an ileum resection, it breaks the enterohepatic circle of bile salts, causing a reduced biliary excretion and a marked decrease of the bile salt pool in the duodenal lumen. Consequently, cholesterol is oversaturated, favoring the formation of biliary stones [70,71]. |
Nephrolithiasis | As a result of steatorrhea, increased free fatty acids are available to bind to calcium, resulting in an increased concentration of non-bound oxalate, which is easily absorbed across the colonic mucosa, where it is moving to the kidneys. Nephrolithiasis is more common among patients with an intact colon. The risk of nephrolithiasis is enhanced by volume depletion, metabolic acidosis, and hypomagnesemia, resulting in decreased renal perfusion, urine output, pH, and citrate excretion [72,73]. |
Metabolic osteopathy | Metabolic changes that occur in SBS result in the depletion of calcium, magnesium, and vitamin D, which results in the demineralization of bone. The release of pro-inflammatory cytokines, steroid use, PN, chronic metabolic acidosis, and renal insufficiency may contribute to the development of metabolic osteopathy [74]. |
(II) Complications related with nutritional therapy | Pathogenesis |
Thrombus-associated venous occlusion | Central venous catheter (CVC)-related thrombosis (CRT) is a severe complication of parenteral nutrition (HPN), which increases its associated morbidity (due to pulmonary embolism) and mortality rates of this population [75,76]. |
Catheter-associated central line bloodstream infections | Primary and intravascular catheter-associated bloodstream infections represent an important clinical entity in the intensive care unit (ICU) and has a poor effect on outcomes. Over-abundant levels of Proteobacteria have been found in the feces of patients with SBS presenting with Ca-CLBI [77,78,79,80]. |
IF-associated liver disease (IFALD) | IFALD is a possible complication in patients with IF who need intravenous support for survival due to severe intestinal dysfunction. An elevation of aminotransferases or cholestasis enzymes in this setting should raise clinical suspicion of this entity, which may progress from hepatic steatosis to cirrhosis. Some factors that increase the risk of this condition are shown in Figure 6. Liver cholestasis can be a life-threatening complication during HPN and may lead to a combined liver–intestinal transplantation (Figure 6) [17,79,81,82]. |
Re-feeding syndrome (RFS) | The switch from a catabolic state to an anabolic state in malnourished patients undergoing refeeding (orally, enterally, or parenteral) may be the cause of all these clinical manifestations, which, in some cases, can lead to death. RS include a complex and extensive list of changes, such as hypophosphatemia, hypomagnesemia, hypokalemia, hyponatremia, hypocalcemia, hyperglycemia, and vitamin deficiency (especially thiamine deficiency), all of which are accompanied by clinical signs and symptoms, reflecting organ dysfunction (cardiovascular, renal, respiratory, and neurological manifestations, among others). Figure 7 and Figure 8 summarize the relationship between the pathophysiology of RS and its clinical presentation [83,84,85,86,87,88,89,90]. |
Requirement | Comment | |
---|---|---|
Energy | 35–45 kcal/kg/day. In some cases, increasing the energy intake up to 60 kcal/kg/day may be necessary. |
Patients with SBS develop compensatory hyperphagia, and it is advisable to take 5–6 meals spaced out during the day. |
Carbohydrates | 20–40% of the daily energy target. | In the absence of a colon, it is not possible to rescue energy inherent in the production of short-chain fatty acids from the bacterial fermentation of sugars. |
Protein | 1.5–2.0 g/kg/day or 20–30% of the daily energy target. | It is preferable to choose lean proteins of high biological value. |
Fat | 40–60% of the daily energy target. | Choose essential fatty acids as the main component of fat intake. Consider MCTs in cases of malabsorption. |
Fluids | Reduce oral hypotonic fluids to 500 mL/day #. Separating solids and liquids (i.e., do not drink anything for half an hour before or after a meal). |
Add sodium chloride to any liquid feeds to make the sodium concentration near 100 mmol/L while keeping osmolality near 300 mOsmol/kg *. |
Oxalate | The restriction is not necessary. | Calcium oxalate stones only occur in patients with a preserved colon. |
Requirement | Comment | |
---|---|---|
Energy | 35–45 kcal/kg/day. In some cases, increasing the energy intake up to 60 kcal/kg/day may be necessary. |
Patients with SBS develop compensatory hyperphagia, and it is advisable to take 5–6 meals spaced out during the day. |
Carbohydrates | 50–60% of the daily energy target. | The colon provides energy (up to 1000 kcal/day) in SBS by releasing the SCFAs resulting from the fermentation of carbohydrates. In addition, it provides nutrition to the colonocytes. |
Protein | 1.5–2.0 g/kg/day or 20–30% of the daily energy target. | It is preferable to choose lean proteins of high biological value. |
Fluids | Isotonic/hypotonic #. | In SBS, the colon plays a vital role in fluid and electrolyte reabsorption, given the additional fluid that enters the colon with a capacity to absorb up to 6 L daily. |
Fat | 20–30% of daily energy target. | In jejunum–colon patients, unabsorbed long-chain fatty acids in the colon are likely to reduce the transit time and reduce their water and sodium absorption, making their diarrhea worsen. Consider MCTs only in the case of severe malabsorption. MCT does not contain essential fatty acids. |
Oxalate | The diet should be low in oxalate. | Nephrolithiasis only occurs in patients with a preserved large bowel. |
Type of Micronutrient and Average Nutritional Intake Ranges | Clinical Signs Reflecting a Deficiency | Measurement | Typical Supplementation in SBS * |
---|---|---|---|
Water-soluble vitamins | Doses (all values per day) | ||
Vitamin B1—thiamine (DRI: 1.1–1.2 mg/day) |
Mental changes (apathy, decrease in short-term memory, confusion, and irritability), cognitive deficits, congestive heart failure, and metabolic lactic acidosis | Whole-blood ThDP or RBCs | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 2.5 mg/day | |||
Vitamin B2—riboflavin (DRI: 1.3 mg/day—males. 1.1 mg/day—females) |
Seborrheic dermatitis of the face, trunk, and scrotum, oral buccal lesions, ocular manifestations, marrow aplasia, and normochromic, normocytic anemia | Glutathione reductase activity in red blood cells | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 3.6 mg/day | |||
Vitamin B3—niacin (DRI: 16 mg/day—adolescents and adult males > 14 years. 14 mg/day—females > 14 years) |
Dementia, dermatitis, and diarrhea | Blood or tissue NAD | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 40 mg/day | |||
Vitamin B5—pantothenic acid (DRI: 5 mg/day for 14 to over 70 years) |
Fall in the diastolic and lability of systolic blood pressure, with postural hypotension, vertigo, and tachycardia. Gastrointestinal and neurological symptoms | Blood pantothenic acid | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 10 mg/day | |||
Vitamin B6—pyridoxine (DRI: 1.3–1.7 mg/day for 14 to over 70 years) |
Microcytic anemia, seborrheic dermatitis with cheilosis and glossitis, angular stomatitis, epileptiform convulsions, confusion, and/or depression | PLP levels. Red cell PLP in serious patients or in the presence of inflammation | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 4 mg/day | |||
Vitamin B7—biotin (DRI: 40 μg/day) |
Ataxia, dermatitis, and alopecia | Direct measure of urine and blood biotin that must be completed with the determination of biotin activity | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 60 μg/day | |||
Vitamin B9—folic acid (DRI: 330 μg/day DFE) |
Glossitis, megaloblastic anemia, pancytopenia, oral ulcers, angular stomatitis, and neuropsychiatric manifestations | Folate level in the plasma or serum—short-term status. In RBCs—long-term status | Oral: 1 mg daily |
HPN and long-term PN: 400 μg/day | |||
Vitamin B12—cobalamin (DRI: 2.4 μg/day) |
Hematological, neurological, neuropsychiatric, and cognitive symptoms | Combination of at least two bio- markers (e.g., holo-TC and MMA), with serum cobalamin as a replacement for holo-TC when the measurement of this latter is unavailable | Oral: 1–2 capsules daily (multivitamin: B1, B2, B3 B5, B6, and B7) |
HPN and long-term PN: 5 μg/day | |||
Vitamin C—ascorbic acid (DRI: 90–100 mg/day) |
Lassitude; shortness of breath; anemia; poor wound healing; myalgia and bone pain; loose teeth; spongy and purplish gums that are prone to bleeding; bulging eyes; scaly, dry, and brownish skin; dry hair that breaks; edema; petechiae; and easy bruising | Total plasma vitamin C (sum of AA and DHAA) or AA. | Oral: 200–500 mg daily ǂ |
HPN and long-term PN: 100–200 mg/day | |||
Fat-soluble vitamins | Doses (all values per day) | ||
Vitamin A (DRI: 700–900 µg/day) |
Night blindness, Bitot spots, foamy appearance on the conjunctiva, xerophthalmia, increased susceptibility to infections, and impairment of the intestinal immune and barrier function | Serum retinol | Oral: 5000–50,000 IU daily # |
HPN and long-term PN: 800–1100 µg/day | |||
Vitamin D (DRI: 15–20 µg/day) |
Osteomalacia and nutritional rickets; increased susceptibility to infections | Serum 25-hydroxyvitamin D (25(OH)D) |
<12 ng/mL: oral: 50,000 IU# once weekly (or calcitriol 0.25–2 mg daily), followed by maintenance:
|
HPN and long-term PN: 200 IU/5 µg/day | |||
Vitamin E (DRI: 15 mg/day) |
Neurological symptoms (balance and coordination disorders and peripheral neuropathy) and muscle weakness | Serum alpha-tocopherol | Oral: 400 IU up to 3 times daily |
HPN and long-term PN: 9–10 mg/day | |||
Vitamin K (DRI: 90–120 µg/day) |
Prolongation of prothrombin time with impaired clotting or bleeding, poor bone development, osteoporosis, and increased cardiovascular disease | Combination of biomarkers and dietary intake | Oral: 2.5 to 10 mg twice weekly to daily, or 10-mg single dose #; can be repeated 48–72 h later |
HPN & long-term PN: 150 µg/day, usually provided by lipid emulsions | |||
Trace mineral | Doses (all values per day) | ||
Iron (DRI: 8 mg/day. 18 mg/day for female 19–50 years old) |
Microcytic anemia | Serum ferritin, sideremia, and transferrin saturation (%) | Oral: 100–200 mg once daily or every other day # ǂ |
HPN and long-term PN: 1.1 mg/day | |||
Copper (DRI: 1.1–2 mg/day) |
Microcytic anemia, neutropenia, osteoporosis, hair depigmentation, cardiac arrhythmias, delayed wound healing, and myeloneuropathy | Serum copper | Oral: 2 mg of elemental copper daily ǂ Higher doses may be needed |
HPN and long-term PN: 0.3–0.5 mg/day- | |||
Chromium (DRI: 20–35 µg/day) |
Hyperglycemia, insulin resistance, elevated plasma fatty acids, weight loss, and peripheral neuropathy | Serum chromium | Oral: 100–200 mg up to 3 times daily |
HPN and long-term PN: 10–15 µg/day | |||
Zinc (DRI: 8–11 mg/day) |
Impairment of immune defense, reduced growth rate, alopecia, skin rash of the face, groins, hands, and feet, delayed sexual development and bone maturation, impaired wound healing, diarrhea, and blunting of taste and smell | Serum zinc | Oral: 50 mg elemental zinc (once or twice daily) Dietary sources such as oysters and mussels can also be considered |
HPN and long-term PN: 3–5 mg/day | |||
Selenium (DRI: 55 µg/day) |
Cardiomyopathy, skeletal muscle myopathy, and skin and nail impact | Serum selenium | Oral: 100–200 mg daily |
HPN and long-term PN: 60–100 µg/day |
Clinical Condition | Criteria | Comments |
---|---|---|
IAFLD | Forthcoming (total bilirubin above 3–6 mg/dL (54–108 μmol/L), progressive thrombocytopenia, and progressive splenomegaly) or overt liver failure (portal hypertension, hepatosplenomegaly, hepatic fibrosis, or cirrhosis because of IFALD). |
Liver biopsy is the gold standard test to identify the stage of liver disease, the timing of transplantation, and the type of transplant required (isolated ITx or combined liver–ITx) It has been suggested that patients with METAVIR stage II fibrosis (perisinusoidal and portal/periportal fibrosis) should be considered for an isolated ITx, whereas those with stage III (bringing fibrosis) or IV (cirrhosis) should be considered for LITx. |
Esophageal varices, ascites, and impaired synthetic function are not always present. | ||
Central venous catheter-related thrombosis (CRVT) | Thrombosis of two or more central veins (loss of right and left internal jugular vein, right and left subclavian vein, or right and left femoral vein). |
CRVT is a severe complication that is responsible for the loss of central venous accesses in patients on HPN and may be an indication for ITx if it affects two or more of the central venous vessels. For adults, this criterion is on a case-by-case basis. |
Catheter-related bloodstream infection (CRBSI). | Frequent central line sepsis: two or more episodes per year of systemic sepsis secondary to line infections requiring hospitalization; a single episode of line-related fungemia; septic shock and/or acute respiratory distress syndrome. |
Children: two admissions to an intensive care unit because of cardiorespiratory failure (mechanical ventilation or inotrope infusion) due to sepsis. For adults, this criterion is on a case-by-case basis, because recurrent episodes of CRBSI have been demonstrated to not be associated with an increased risk of death. |
Other indications | Refractory electrolyte changes and frequent episodes of dehydration. High risk of death attributable to underlying diseases, such as congenital mucosal disorders, ultra-short bowel syndrome (gastrostomy; duodenostomy; residual small bowel <10 cm in infants and <20 cm in adults), and invasive intra-abdominal desmoid tumors; patients with high morbidity (frequent hospitalization, narcotic dependency, and inability to function (i.e., pseudo-obstruction; high output stoma)) or a low acceptance of long-term PN, especially in young patients. |
This entry is adapted from the peer-reviewed paper 10.3390/nu16020246