Jejunoileal bypass
Encyclopedia
Jejunoileal Bypass was a surgical weight loss procedure performed from the 1950s through the 1970s in which all but 30 cm (12") to 45 cm (18") of the small bowel
were detached and set to the side.
Many complications that followed jejunoileal bypass operations performed for the relief of morbid obesity
were caused by bacterial overgrowth
in the excluded blind loop. The arthritis-dermatitis syndrome was one of the common distressing disorders. The pathogenetic mechanism was thought to be an immune-complex-mediated process related to bypass enteritis.
of the proximal jejunum to distal ileum. In both instances an extensive length of small intestine was bypassed, not excised, excluding it from the alimentary stream.
In both these variants a total of only about 35 cm (18") of normally absorptive small intestine was retained in the absorptive stream, compared with the normal length of approximately 7 metres (twenty feet). In consequence, malabsorption of carbohydrate, protein, lipids, minerals and vitamins inevitably occur, Where the end-to-side technique was used, reflux of bowel content back up the defunctionalized small intestine allowed absorption of some of the refluxed material resulting in less weight loss initially and greater subsequent weight regain.
Bile is secreted by the liver, enters the upper small intestine by way of the bile duct
, and is absorbed in the small intestine. Bile has an important role in fat digestion, emulsifying fat as the first stage in its digestion. Bypassing the major site of bile acid
reabsorption in the small intestine therefore further reduces fat and fat soluble vitamin absorption. As a result, huge amounts of fatty acid
s, which are normally absorbed in the small intestine, enter the colon where they cause irritation of the colon wall and the secretion of excessive volumes of water and electrolytes, especially sodium and potassium, leading to diarrhea. This diarrhea is the major patient complaint and has characterized jejunoileal bypass in the minds of patient and physician alike since the procedure was introduced.
Bile salts
help to keep cholesterol in solution in the bile. Following JIB, the bile salt pool is decreased as a consequence of reduced absorption in the small intestine and bile salt losses in the stool. The relative cholesterol concentration in gallbladder bile rises and cholesterol crystals precipitate in the gallbladder bile, forming a nidus for development of cholesterol gallstones in the gallbladder. Specific vitamin deficiencies also occur; Vitamin D
and Calcium deficiencies lead to thinning of bone with bone pain
and fractures as a result of osteoporosis and osteomalacia. Bypass of the terminal ileum, which is the specific site of vitamin B12
absorption, leads to Vitamin B12 deficiency with a specific peripheral neuropathy
. Vitamin A deficiency
can induce night blindness
. Calcium oxalate
renal stones
occur commonly following JIB, along with increased colonic absorption of oxalate. The colonic absorption of oxalate has been attributed to:
Patients with intestinal bypass develop diarrhea 4-6 times daily. The frequency of stooling varying directly with fat intake. There is a general tendency for stooling to diminish with time, as the short segment of small intestine remaining in the alimentary stream increases in size and thickness, developing its capacity to absorb calories and nutrients, thus producing improvement in the patients nutrition and counterbalancing the ongoing weight loss. This happy result does not occur in every patient, but approximately one third of those undergoing "Intestinal Bypass" have a relatively benign course. Unfortunately, even this group is at risk of significant late complications, many patients developing irreversible hepatic cirrhosis
several years after the procedure.
Listing of jejuno-ileal bypass complications:
Mineral and electrolyte imbalance:
Protein calorie malnutrition:
Enteric complications:
Extra-intestinal manifestations:
Some of these features may coincide in bowel-associated dermatosis-arthritis syndrome.
Renal disease:
Miscellaneous:
The multiple complications associated with JIB led to a search for alternative procedures, one of which was gastric bypass, a procedure that is described in detail later. In 1983 Griffen et al. reported a comprehensive series comparing the results of jejuno-ileal bypass with gastric bypass. 11 of 50 patients who underwent JIB required conversion to gastric bypass within 5 years, leading Griffen to abandon jejuno-ileal bypass.
JIB can be summed up as having: a. Good Weight Loss, b. Malabsorption with multiple deficiencies, c. Diarrhea, d. Severe Pain Issues That are not fully understood, e.Possible Death
As a consequence of all these complications, jejuno-ileal bypass is no longer a recommended Bariatric Surgical Procedure. Indeed, the current recommendation for anyone who has undergone JIB, and still has the operation intact, is to strongly consider having it taken down and converted to one of the gastric restrictive procedures.
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
were detached and set to the side.
Many complications that followed jejunoileal bypass operations performed for the relief of morbid obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
were caused by bacterial overgrowth
Small bowel bacterial overgrowth syndrome
Small bowel bacterial overgrowth syndrome , or small intestinal bacterial overgrowth , also termed bacterial overgrowth; is a disorder of excessive bacterial growth in the small intestine. Unlike the colon , which is rich with bacteria, the small bowel usually has less than 104 organisms per...
in the excluded blind loop. The arthritis-dermatitis syndrome was one of the common distressing disorders. The pathogenetic mechanism was thought to be an immune-complex-mediated process related to bypass enteritis.
Problems with Jejuno-Ilial Bypass
Two variants of jejunoileal anastomosis were developed, the end-to-side and end-to end (Scott, Dean et al. 1973) anastomosesAnastomosis
An anastomosis is the reconnection of two streams that previously branched out, such as blood vessels or leaf veins. The term is used in medicine, biology, mycology and geology....
of the proximal jejunum to distal ileum. In both instances an extensive length of small intestine was bypassed, not excised, excluding it from the alimentary stream.
In both these variants a total of only about 35 cm (18") of normally absorptive small intestine was retained in the absorptive stream, compared with the normal length of approximately 7 metres (twenty feet). In consequence, malabsorption of carbohydrate, protein, lipids, minerals and vitamins inevitably occur, Where the end-to-side technique was used, reflux of bowel content back up the defunctionalized small intestine allowed absorption of some of the refluxed material resulting in less weight loss initially and greater subsequent weight regain.
Bile is secreted by the liver, enters the upper small intestine by way of the bile duct
Bile duct
A bile duct is any of a number of long tube-like structures that carry bile.Bile, required for the digestion of food, is excreted by the liver into passages that carry bile toward the hepatic duct, which joins with the cystic duct to form the common bile duct, which opens into the intestine.The...
, and is absorbed in the small intestine. Bile has an important role in fat digestion, emulsifying fat as the first stage in its digestion. Bypassing the major site of bile acid
Bile acid
Bile acids are steroid acids found predominantly in the bile of mammals. Bile salts are bile acids compounded with a cation, usually sodium. In humans, the salts of taurocholic acid and glycocholic acid represent approximately eighty percent of all bile salts. The two major bile acids are cholic...
reabsorption in the small intestine therefore further reduces fat and fat soluble vitamin absorption. As a result, huge amounts of fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s, which are normally absorbed in the small intestine, enter the colon where they cause irritation of the colon wall and the secretion of excessive volumes of water and electrolytes, especially sodium and potassium, leading to diarrhea. This diarrhea is the major patient complaint and has characterized jejunoileal bypass in the minds of patient and physician alike since the procedure was introduced.
Bile salts
Bile
Bile or gall is a bitter-tasting, dark green to yellowish brown fluid, produced by the liver of most vertebrates, that aids the process of digestion of lipids in the small intestine. In many species, bile is stored in the gallbladder and upon eating is discharged into the duodenum...
help to keep cholesterol in solution in the bile. Following JIB, the bile salt pool is decreased as a consequence of reduced absorption in the small intestine and bile salt losses in the stool. The relative cholesterol concentration in gallbladder bile rises and cholesterol crystals precipitate in the gallbladder bile, forming a nidus for development of cholesterol gallstones in the gallbladder. Specific vitamin deficiencies also occur; Vitamin D
Vitamin D
Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique both because it functions as a prohormone and because the body can synthesize it when sun exposure is adequate ....
and Calcium deficiencies lead to thinning of bone with bone pain
Bone pain
Bone pain is a debilitating form of pain emanating from the bone tissue. It occurs as a result of a wide range of diseases and/or physical conditions and may severely impair the quality of life for patients who suffer from it...
and fractures as a result of osteoporosis and osteomalacia. Bypass of the terminal ileum, which is the specific site of vitamin B12
Vitamin B12
Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins...
absorption, leads to Vitamin B12 deficiency with a specific peripheral neuropathy
Peripheral neuropathy
Peripheral neuropathy is the term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of or trauma to the nerve or the side-effects of systemic illness....
. Vitamin A deficiency
Retinol
Retinol is one of the animal forms of vitamin A. It is a diterpenoid and an alcohol. It is convertible to other forms of vitamin A, and the retinyl ester derivative of the alcohol serves as the storage form of the vitamin in animals....
can induce night blindness
Nyctalopia
Nyctalopia is a condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, or be caused by injury or malnutrition...
. Calcium oxalate
Calcium oxalate
Calcium oxalate is a chemical compound that forms needle-shaped crystals, known in plants as raphides. A major constituent of human kidney stones, the chemical is also found in beerstone, a scale that forms on containers used in breweries...
renal stones
Kidney stone
A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine...
occur commonly following JIB, along with increased colonic absorption of oxalate. The colonic absorption of oxalate has been attributed to:
- Exposure of colonic mucosa to excessive bile salts and possibly bile acids, increasing colonic permeability to oxalate, or
- Excessive quantities of fatty acids in the gut form soaps with calcium, reducing its availability to form insoluble calcium oxalate leading to the persistence of soluble and absorbable oxalate in the colon.
Patients with intestinal bypass develop diarrhea 4-6 times daily. The frequency of stooling varying directly with fat intake. There is a general tendency for stooling to diminish with time, as the short segment of small intestine remaining in the alimentary stream increases in size and thickness, developing its capacity to absorb calories and nutrients, thus producing improvement in the patients nutrition and counterbalancing the ongoing weight loss. This happy result does not occur in every patient, but approximately one third of those undergoing "Intestinal Bypass" have a relatively benign course. Unfortunately, even this group is at risk of significant late complications, many patients developing irreversible hepatic cirrhosis
Cirrhosis
Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...
several years after the procedure.
Complications
JIB is the classic example of a malabsorptive weight loss procedure. Some modern procedures utilize a lesser degree of malabsorption combined with gastric restriction to induce and maintain weight loss. Any procedure involving malabsorption must be considered at risk to develop at least some of the malabsorptive complications exemplified by JIB. The multiple complications associated with JIB while considerably less severe than those associated with Jejunocolic anastomosis, were sufficiently distressing both to the patient and to the medical attendant to cause the procedure to fall into disrepute.Listing of jejuno-ileal bypass complications:
Mineral and electrolyte imbalance:
- Decreased serum sodium, potassium, magnesium and bicarbonate
- Decreased sodium chloride
- Osteoporosis and osteomalacia secondary to protein depletion, calcium and vitamin D loss, and acidosis
Protein calorie malnutrition:
- Hair loss, anemiaAnemiaAnemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...
, edemaEdemaEdema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
, and vitamin depletion - Cholelithiasis
Enteric complications:
- Abdominal distension, irregular diarrhea, increased flatus, pneumatosis intestinalisPneumatosis intestinalisIn radiology, pneumatosis intestinalis is a sign on x-ray which is highly suggestive for necrotizing enterocolitis.It refers to gas cysts in the bowel wall. This is in contrast to gas in the lumen which is normal.-References:...
, colonic pseudo-obstruction, bypass enteropathy, volvulus with mechanical small bowel obstructionBowel obstructionBowel obstruction is a mechanical or functional obstruction of the intestines, preventing the normal transit of the products of digestion. It can occur at any level distal to the duodenum of the small intestine and is a medical emergency...
Extra-intestinal manifestations:
- ArthritisArthritisArthritis is a form of joint disorder that involves inflammation of one or more joints....
- Severe pain issues that are not fully understood
- Liver disease, occurs in at least 30%
- Acute liver failureLiver failureAcute liver failure is the appearance of severe complications rapidly after the first signs of liver disease , and indicates that the liver has sustained severe damage . The complications are hepatic encephalopathy and impaired protein synthesis...
may occur in the postoperative period, and may lead to death acutely following surgery. - SteatosisSteatosisIn cellular pathology, steatosis is the process describing the abnormal retention of lipids within a cell. It reflects an impairment of the normal processes of synthesis and elimination of triglyceride fat. Excess lipid accumulates in vesicles that displace the cytoplasm...
, "alcoholic" type hepatitis, cirrhosisCirrhosisCirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...
, occurs in 5%, progresses to cirrhosis and death in 1-2% - Erythema nodosumErythema nodosumErythema nodosum is an inflammation of the fat cells under the skin characterized by tender red nodules or lumps that are usually seen on both shins...
, non-specific pustular dermatosis - Weber-Christian disease
Some of these features may coincide in bowel-associated dermatosis-arthritis syndrome.
Renal disease:
- HyperoxaluriaHyperoxaluriaHyperoxaluria is an excessive urinary excretion of oxalate. Individuals with hyperoxaluria often have calcium oxalate kidney stones. Sometimes called Bird's disease, after Golding Bird who was first to describe the condition.-Causes:...
, with oxalate stones or interstitial oxalate deposits, immune complex nephritisNephritisNephritis is inflammation of the nephrons in the kidneys. The word "nephritis" was imported from Latin, which took it from Greek: νεφρίτιδα. The word comes from the Greek νεφρός - nephro- meaning "of the kidney" and -itis meaning "inflammation"....
, "functional" renal failureRenal failureRenal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
.
Miscellaneous:
- Peripheral neuropathyPeripheral neuropathyPeripheral neuropathy is the term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of or trauma to the nerve or the side-effects of systemic illness....
, pericarditisPericarditisPericarditis is an inflammation of the pericardium . A characteristic chest pain is often present.The causes of pericarditis are varied, including viral infections of the pericardium, idiopathic causes, uremic pericarditis, bacterial infections of the precardium Pericarditis is an inflammation of...
, pleuritis, hemolytic anemiaHemolytic anemiaHemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells , either in the blood vessels or elsewhere in the human body . It has numerous possible causes, ranging from relatively harmless to life-threatening...
, neutropeniaNeutropeniaNeutropenia, from Latin prefix neutro- and Greek suffix -πενία , is a granulocyte disorder characterized by an abnormally low number of neutrophils, the most important type of white blood cell...
, and thrombocytopeniaThrombocytopeniaThrombocytopenia is a relative decrease of platelets in blood.A normal human platelet count ranges from 150,000 to 450,000 platelets per microliter of blood. These limits are determined by the 2.5th lower and upper percentile, so values outside this range do not necessarily indicate disease...
The multiple complications associated with JIB led to a search for alternative procedures, one of which was gastric bypass, a procedure that is described in detail later. In 1983 Griffen et al. reported a comprehensive series comparing the results of jejuno-ileal bypass with gastric bypass. 11 of 50 patients who underwent JIB required conversion to gastric bypass within 5 years, leading Griffen to abandon jejuno-ileal bypass.
JIB can be summed up as having: a. Good Weight Loss, b. Malabsorption with multiple deficiencies, c. Diarrhea, d. Severe Pain Issues That are not fully understood, e.Possible Death
As a consequence of all these complications, jejuno-ileal bypass is no longer a recommended Bariatric Surgical Procedure. Indeed, the current recommendation for anyone who has undergone JIB, and still has the operation intact, is to strongly consider having it taken down and converted to one of the gastric restrictive procedures.