Short Bowel Syndrome (SBS) and Other GI Disorders

Section 1: Short Bowel Syndrome
What are the goals in managing short bowel syndrome (SBS)? What are ways these goals are reached?
- Providing adequate nutrition and hydration.
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Preventing any complications as they arise. -
Decreasing or eliminating the need for total parenteral nutrition (TPN) and intravenous (IV) hydration. -
Maximizing the use of the existing bowel and stimulating intestinal adaptation.
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Increase the amount of time nutrients and fluids spend in the intestine by slowing intestinal transit. -
Controlling the increased secretion of stomach acid, also known as gastric hypersecretion. - Avoiding things that can increase stool output, such as drinks or foods high in simple sugars or considered 'osmotic agents.' Even low-calorie sweeteners such as “sugar alcohols (sorbitol)” are osmotic agents.
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Treating small intestinal bacterial overgrowth as it arises to decrease bloating and diarrhea. -
Limit the amount of food and fluid intake if there is exceptionally high ostomy or stool output.
Describe the basics of GI tract anatomy and how it affects a short bowel syndrome (SBS) patient.
What is short bowel syndrome (SBS)?
What causes short bowel syndrome in adults?
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Complications from Crohn's disease -
Volvulus -
Mesenteric Ischemia or other vascular injury or disease -
Thrombosis (blood clots) -
Post-operative complications, particularly weight loss surgeries -
Certain cancers, such as neuroendocrine tumors -
Trauma -
Radiation damage (radiaton enteritis) -
Intussusception: One section of either the large or small intestine folds into itself, much like a collapsible telescope.
What are signs and symptoms of short bowel syndrome?
- Diarrhea or high ostomy output
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Dehydration -
Gas and stomach pain -
Bloating -
Poor weight gain -
Vomiting -
Fatigue -
Food sensitivities -
Kidney stones (due to high oxalate levels) -
Ulcers (due to gastric hypersecretion of acid, see SBS complications section) -
Heartburn -
Malnutrition: Results when the body does not get the right amount of vitamins, minerals, and nutrients it needs to maintain healthy tissues and organ function.
Symptoms will vary based on the underlying diagnosis. The above symptoms are in relation to malnutrition and malabsorption.
How is short bowel syndrome diagnosed?
Multiple tests may be used to help diagnose short bowel and rule out other gastrointestinal disorders. Tests also serve to determine your nutritional status.
What are 3 common ostomies you may have after a bowel resection?
Section 2: GI Disorders and Causes of Short Bowel
Crohn's Disease in Adults
Crohn’s disease is a type of inflammatory bowel disease (IBD) in which your immune system recognizes the lining of your intestine as foreign. This causes the immune system to attack the intestinal epithelium, causing inflammation. Crohn’s disease usually follows a pattern of repeating cycles of intermittent flares in which the condition worsens and symptoms are present. Then a period of remission in which inflammation is controlled and symptoms are absent. The symptoms can range from mild to severe and can be disabling.
Signs and Symptoms:
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Abdominal pain
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Diarrhea
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Fatigue
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Unintentional weight loss
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Anal pain
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Arthritis: Typically in the larger joints and is most active when bowel symptoms are active.
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Mouth sores: Usually found between the gums and lower lip, or along the sides of the tongue.
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Eye inflammation (uveitis or scleritis): Can cause eye pain, blurry vision, and sensitivity to light.
Diagnosis: Crohn’s disease is confirmed through an intestinal biopsy taken during a colonoscopy. The specimen is studied microscopically for specific histological features, namely clusters of inflammatory cells called granulomas.
Treatment:
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The first step of treatment is to manage Crohn’s with medications.
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Anti-inflammatory medications (e.g., corticosteroids, 5-aminosalicylates, sulfasalazine), can help to counteract and prevent inflammation.
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Immunomodulators (e.g. azathioprine, methotrexate, and 6-mercaptopurine) and biologic response modifiers, (infliximab, adalimumab, certolizumab), can reduce the immune response to attack the intestines.
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In some instances, the chronic inflammation and scarring from Chrohn's can lead to complications that require surgery.
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Surgery may result in massive resection and short bowel syndrome.
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In this case, you may need to seek care from an intestinal rehabilitation and transplantation center to optimize your nutritional status and remaining intestine.
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Common complications from Crohn's requiring resection of the bowel:
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Stricture: Narrowing of the intestinal wall
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Perforation: This occurs when the intestinal wall is punctured or torn.
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Hemorrhage: This is excessive bleeding.
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Abscess formation: This is a localized collection of infection
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Fistula: This is an abnormal pathway leading from one part of the intestine to another portion of intestine or to another organ in the body. In some cases a fistula may also lead outside the body onto the skin.
Volvulus
A volvulus occurs when part of the intestine is twisted or rotates on itself and the mesentery. The mesentery is the supportive tissue that anchors the intestine to the abdomen's back wall and contains the essential blood vessels, lymphatics, and nerves to supply the intestine. When the intestine twists, it creates a bowel obstruction that cuts off the intestine’s blood supply, therefore affecting bowel function and ultimately resulting in death to the bowel if not treated promptly.
Bowel necrosis (death) results in the requirement of massive bowel resection (removal). This often leaves an individual with short bowel syndrome and the inability to maintain adequate nutrition by mouth. The cause of the twisting is not known.
Symptoms may include:
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Severe abdominal pain
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Nausea and vomiting
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Constipation
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Bloody stools
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Abdominal distention.
Diagnosis is based on clinical picture, physical exam, abdominal x-ray, CT scan, and/or upper/lower GI barium series.
Treatment is surgical with correction of the volvulus and resection of any necrotic (dead) bowel. If the resection is massive, referral to an intestinal rehabilitation and transplantation center may be indicated.
Intestinal Ischemia (Mesenteric Ischemia)
Ischemia is a general term that means an inadequate blood supply to an organ or part of the body. The intestine is supplied by various blood vessels and is a highly vascularized organ.
There are several different causes of ischemia in the intestine:
1. Arterial thrombosis (blood clot): The artery called the superior mesenteric artery (SMA) supplies the majority of the small intestine and the first portion of the colon up to the splenic flexure, the bend between the transverse colon (2nd part) and descending (3rd part) colon. When a blood clot in the superior mesenteric artery (SMA) creates a blockage, it stops the delivery of oxygen to the intestine, and results in the death of the organ.
2. Adhesions: Adhesions are scar tissue that form from previous trauma or surgery. In some cases, adhesions can trap the intestine and its vessels, leading to ischemia.
3. Embolus: In some cases, a blood clot can travel from another location in the body and become lodged in an intestinal vessel, leading to intestinal ischemia and necrosis. This is common in individuals with atrial fibrillation and heart arrhythmias.
4. Other possible causes of ischemia may be due to diseases of the blood vessels or overactive blood clotting disorders (hypercoagulable states).
Symptom: Severe abdominal pain is usually the presenting symptom. You may also experience fever, diarrhea, and nausea/vomiting.
Diagnosis: Diagnosis is based on history, CT scan, and/or angiography. Bloodwork may also reveal abnormal cell counts and levels.
When a blockage occurs, the necrotic (dead) intestine must be removed, leaving the individual with a short bowel, which is insufficient to provide the essential nutrients required to sustain life. Individuals usually will be placed on parenteral nutrition and referred to an intestinal rehabilitation and transplantation center to optimize nutrition and receive further treatment.
Neuroendocrine Tumors (NETs, aka Carcinoid Tumors)
A neuroendocrine tumor (NET) begins in the specialized cells of the body’s neuroendocrine system. These cells can be found in many organs of the body, and they carry messages from the nervous system to the endocrine system, ultimately causing the release of hormones. Hormones are substances that regulate many functions in our body, such as blood pressure, digestion, and heart rate.
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Abdominal pain -
Bloating -
Nausea/vomiting -
Diarrhea -
Changes in stool color (gray or whitish color) -
Weight loss -
Blood in stool
Radiation Enteritis
Radiation enteritis is damage to the lining of the intestinal tract caused by radiation therapy.
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Cervical cancer -
Pancreatic cancer -
Prostate cancer -
Uterine cancer -
Colon and rectal cancer
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Diarrhea -
Abdominal pain -
Nausea and vomiting -
Weight loss -
Bleeding from rectum -
Loss of appetite
Gastroparesis
The literal translation of gastroparesis is "stomach paralysis." It is a condition in which the motility of the stomach is either abnormal or absent and results in delayed stomach emptying.
Symptoms:
- Nausea and vomiting
- Bloating
- Getting full quickly
- Heartburn
- Upper abdominal pain
Diagnosis:
- Gastric emptying study: A nuclear medicine test in which you ingest some type of food (usually an egg sandwich) which contains a radioactive tracer to monitor how long it takes for food to leave your stomach. A delay in emptying indicates gastroparesis.
- Gastroduodenal manometry: This test uses a specialized tube to measure the contractions of you stomach and upper portion of your small intestine, the duodenum. Usually the test will run in a fasted state and then while you are eating to monitor stomach contractions.
- Upper endoscopy: This is when a small tube with a pin-point camera at the end is advanced down your throat and into your stomach. While this cannot diagnose gastroparesis, it can help rule out other possible causes of upper abdominal pain and other symptoms you may be having, such as a gastric ulcer.
- SmartPill®: This is a capsule that can measure temperature, pH, and pressure changes as it travels through your digestive tract. It can monitor the rate at which things are moving through your system.
Treatment:
- Diet modification: Working with a nutritionist is important for individual's with gastroparesis.
- Medications: The purpose of medication is to help increase stomach emptying, however, the medications that do exist often have unwanted side effect profiles. Speak with your team about options.
- Endoscopic Options: A balloon dilator may be positioned to engage the pylorus (opening from stomach to duodenum) and dilated (expanded) to 15 or 20 mm. The pylorus may also be injected with botulinum toxin (Botox) to relax the pyloric muscle. Stomach emptying may often improve following these strategies used separately or together, but relief of symptoms is inconsistent.
- Surgical options- Gastric pacemaker: Uses electrical stimulation to enhance gastrointestinal contractile activity. The pacemaker is surgically implanted under the skin and is connected to electrodes placed on the stomach wall.
Chronic Intestinal Pseudo-Obstruction (CIPO)
Chronic Intestinal Pseudo-Obstruction (CIPO) is a rare condition that can affect all segments of the gastrointestinal tract and is characterized by failure of the movement of intestinal contents due to the inability to generate suitable motor patterns, either due to a deficit in the neuropathic (nerve) or myopathic (muscle) forces.
Commonly, in adults, it is secondary to neuromuscular diseases such as scleroderma, systemic sclerosis, bronchial carcinoma, or amyloidosis. In other cases, it may be a primary disease that selectively affects the smooth muscle or enteric nerve plexuses in which it may be a degenerative or inflammatory process.
Rarely, pseudo-obstruction arises acutely in a condition known as Ogilvie’s syndrome, and is concurrent with non-gastrointestinal disorders such as myocardial infarction, infection, or non-operative trauma. This syndrome is characterized by acute colonic dilation, pain, and abdominal distention.
Signs and Symptoms:
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Abdominal pain
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Distention
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Nausea and/or vomiting
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Constipation
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Early satiety (fullness)
Diagnosis:
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Manometry: The gold standard for diagnosis as it measures the contractions of the intestinal tract and can help to localize the functioning areas of the gastrointestinal tract. Manometry can help evaluate functional areas prior to any surgical intervention or creation of a stoma.
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Gastric emptying studies: Direct, noninvasive measurements of liquid or solid gastric emptying to assess the function of the stomach.
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Full-thickness biopsy: Full-thickness biopsies are useful in the diagnosis of autoimmune or mitochondrial etiology for chronic intestinal pseudo obstruction and can get a better understanding of abnormalities of the enteric nervous system.
Treatment:
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Nutritional Support: The majority of patients will require nutritional support, often requiring parenteral nutrition (PN).
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Prokinetics: These medications help to increase the motility, or movement of contents through the intestine. Examples include erythromycin, octreotide, prucalopride, and tegaserod.
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Antibiotics: Poor motility can result in the overgrowth of bacteria in the intestine. If you have small intestinal bacterial overgrowth (SIBO), an antibiotic may be prescribed to help treat your symptoms.
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Surgical: A decompressing gastrostomy or jejunostomy may be beneficial to help decompress the stomach or intestine in individuals with CIPO.
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Small Intestine Transplant: This may be indicated in patients who have PN dependency and are in PN failure. It is important to evaluate the presence or absence of gastric or colonic dysfunction, so the decision can be made whether to proceed with an isolated or multivisceral transplant.
Complications from Bariatric Surgery (Weight-loss Surgery)
Bariatric and gastric bypass surgery are procedures used to help people lose weight. The downside to these procedures is that there is a risk of complications, many of which can lead to massive bowel resection and short bowel syndrome. In these cases, it may leave an individual with the need for parenteral nutrition (PN) and further treatment at an intestinal rehabilitation or transplantation center.
- Obstructions due to adhesions
- Internal hernias
- Volvulus
- Incarcerated incisional hernias
- Mesenteric ischemia
- Complications in the bypassed intestine
Desmoid Tumors and Gardner's Syndrome
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Desmoid tumors are benign (not harmful) tumors. Still, they are infiltrative (grow into healthy tissue) and locally invasive, entrap the mesenteric vasculature, and can lead to obstructions and fistulas.
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Desmoid tumors are generally unresponsive to standard chemotherapeutic agents; thus, complete surgical removal of the intestine is often required. This can leave an individual with a short bowel that is insufficient to support nutritional needs.
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If an individual requires additional nutritional support, referral to an intestinal rehabilitation and transplantation center may be beneficial. The team at the center can determine the best course of treatment, including rehabilitation or transplantation.
Gardner's Syndrome
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Desmoid tumors are commonly associated with Gardner’s syndrome. Gardner’s syndrome is a form of familial adenomatous polyposis (FAP) that is characterized by multiple colorectal polyps and various types of tumors, both benign (not harmful) and malignant (harmful).
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Individuals with Gardner’s will commonly contract different types of tumors, such as osteomas (bone tumor), fibromas (tumor of connective tissue), lipomas (tumor of fat tissue), and desmoid tumors (connective tissue).
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It is not uncommon for Gardner’s patients to undergo a total proctocolectomy (removal of colon, rectum, and anus) to treat the primary disease and prevent progression to cancer.
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Apart from a total protocolectomy, resections for desmoid tumors in the intestine can be performed, but multiple resections can lead to short bowel syndrome and insufficient absorption.
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Small bowel desmoids may also be treated with radiation, which can lead to radiation enteritis in the remaining bowel and impede absorption.
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If an individual is unable to maintain nutritional status and requires additional nutritional support, referral to an intestinal rehabilitation and transplantation center may be beneficial. The team at the center can determine the best course of treatment, including rehabilitation or transplantation.
Section 3: Short Bowel Complications
Gastric Acid Hypersecretion
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When there is a significant loss of a portion of the small bowel, the signal to stop stomach acid secretion is lost, resulting in excess secretion of stomach acid.
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This needs to be treated as the stomach acid deactivates necessary pancreatic enzymes, increases stool output, and damages the lining of the esophagus and intestine.
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Treatment usually includes some form of proton-pump inhibitor (PPI), but the form prescribed must not be delayed-release or enteric-coated as these will not properly absorb in a SBS patient. Depending on the extent of bowel loss, an intravenous (IV) form of a PPI may be required. Your team will determine the best anti-acid medication for you.
Small Intestinal Bacterial Overgrowth (SIBO)
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Intestinal motility: Movement of contents through the intestine helps to ensure bacteria doesn't build-up. Many SBS patients have impaired motility, leading to SIBO. -
Stomach acid: Usually your stomach acid helps to kill some bacteria and ensures it doesn't overgrow. Many SBS patients require anti-acid medications to control gastric acid hypersecretion; thus, it allows more bacteria to grow. -
Ileocecal valve: Usually, the ileocecal valve prevents backflow of bacteria from the colon to the small intestine.
- Nausea
- Gas and bloating
- Malabsorption
- Increased diarrhea or ostomy output
What are complications associated with short bowel syndrome?
1. Malnutrition: This is from the intestine's inability to absorb the nutrients needed to grow and develop properly.
2. Electrolyte Imbalances and Dehydration: This is due to high output and diarrhea.
3. Vitamin and Mineral Deficiencies
4. Small Intestinal Bacterial Overgrowth (SIBO)
5. Gastric Hypersecretion
6. Kidney stones
7. Steatorrhea (fat in stool)
8. Osteoporosis and Metabolic Bone Disease
9. Acidosis
10. Long-Term TPN Complications: Infection, Blood Clots, and Liver Damage
Dehydration
It is common for individuals with short bowel to have high output and diarrhea, leading to dehydration.
Signs and Symptoms of Dehydration:
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Excessive thirst -
Dark-colored urine -
Infrequent urination -
Lethargy -
Dizziness, or feeling faint -
Dry skin
Dehydration can lead to electrolyte abnormalities, which can be serious. If you are experiencing any of these signs or symptoms, you should contact your team immediately.
Electrolyte Imbalances
Electrolytes are electrically charged minerals and compounds that help your body do much of its work.
What are some of the most important electrolytes?
- Sodium (Na+)
- Potassium (K+)
- Magnesium (Mg +2)
- Calcium (Ca +2)
- Chloride (Cl-)
- Phosphorous/Phosphate (PO4-)
With excessive diarrhea, electrolyte imblances can occur very quickly and are very serious.
Diagnosis: A simple blood test can check your electrolyte values.
Treatment: If you require replenishment of electrolytes, your team may reccomend certain oral rehydration solutions, intravenous (IV) fluids, or IV supplements to bring levels back to normal. If you are on total parenteral nutrition (TPN), your team may be able to make adjustments in the TPN formula.
Kidney Stones
- If you are a short bowel syndrome patient with a colon, you may be at risk for forming oxalate-calcium kidney stones.
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Oxalate is a substance that is found in plant-based foods. When these foods are broken down, oxalate is released as a by-product. Normally, oxalate binds to calcium in the intestine and is pooped out. -
In individuals with short bowel who have fat malabsorption, the fat binds with the calcium, leaving the oxalate free in the colon, where it is reabsorbed into the bloodstream. -
Back in the body, the oxalate reaches the kidney, binds with calcium, and can form kidney stones.
Prevention includes avoiding foods high in oxalate, such as:
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Tea -
Chocolate -
Nuts -
Leafy green vegetables -
Berries -
Wheat germ/bran
Other ways to help avoid kidney stones:
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Stay hydrated. -
Increase the amount of calcium in the diet, if tolerated. -
Take calcium supplements if recommended by your team. -
Avoid oxalate-rich foods.
Steatorrhea
Steatorrhea is when dietary fat remains in your stool after passing through the small intestine unabsorbed.
Why does this occur in a short bowel patient?
- Fats usually combine with bile salts created by your liver and are reabsorbed in your terminal ileum (the third portion of the small intestine).
- Many individuals with short bowel syndrome do not have this portion of the ileum (esp. if >100 cm or 3.3 ft. of ileum resected), resulting in the continued loss of bile salts.
- The liver, which produces the bile salts, cannot 'keep up' with production, and the supply of bile salts becomes depleted.
- The result is that fats pass through the intestine unabsorbed.
- This leads to a greasy, foul-smelling stool that floats and is usually grey in color.
How is this treated?
Diet
- It will depend on your situation. Sometimes, simple dietary changes, such as a low-fat diet, can help to solve the problem.
Bile Acid Sequestrants (Binders)
- If you have an intact colon, the bile salts that were not absorbed by the ileum may reach the colon and irritate its lining.
- This can lead to increased diarrhea.
- In these cases, your team may recommend certain medications to help decrease diarrhea caused by the bile salts, called bile salt sequestrants.
- An example of this type of medication is cholestyramine. It reduces the bile salt diarrhea by increasing the removal of bile acids from the body.
- The downside of these medications is that they can interfere with the absorption of essential things, like fat-soluble vitamins and essential fatty acids.
- Your team will closely monitor you to ensure you maintain your nutritional status.
Vitamin and Mineral Deficiencies
Vitamin and mineral deficiencies will vary depending on the length and location of intestinal resection/ portion of your intestine that is missing. In particular, if the ileum is missing, the absorption of fat-soluble vitamins A, D, E, and K, are often insufficient.
Common deficiencies may include:
Vitamin A: Deficiency can lead to issues with night vision.
Vitamin D: Deficiency can lead to problems with proper bone formation and growth.
Vitamin E: Deficiency may present as loss of voluntary muscle coordination (known as ataxia), tingling sensations (paresthesia), or visual disturbances.
Vitamin K: Deficiency can lead to prolonged bleeding and easy bruising.
Another common deficiency is vitamin B12 since it is only absorbed in the terminal ileum, the final portion of the small intestine. You may require supplementation of this and many other vitamins and minerals.
Osteoporosis and Metabolic Bone Disorders
It is common for individuals with short bowel syndrome to have bone disease due to malnutrition, vitamin and mineral deficiencies, long-term TPN use, and medications (such as the use of steroids for underlying conditions).
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Osteomalacia (caused by severe vitamin D deficiency) -
Osteopenia -
Osteoporosis
Acidosis
Acidosis results when there is too much lactic acid in the bloodstream.
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Confusion -
Altered mental status -
Blurred vision -
Slurred speech
Section 4: Additional Resources
Helpful Downloads from Transplant Unwrapped
Sign-Up or Log-In to Access:
UVA Nutrition Website
University of Virginia Nutrition resource webpage with numerous downloads and information on short bowel syndrome and nutrition.
Transplant Unwrapped: Learn From Others
Transplant Unwrapped: Support Programs