eMedicine Specialties > Gastroenterology > Intestine

Afferent Loop Syndrome

Sandeep Mukherjee, MB, BCh, MPH, FRCPC, Associate Professor, Department of Internal Medicine, Section of Gastroenterology and Hepatology, University of Nebraska Medical Center; Consulting Staff, Section of Gastroenterology and Hepatology, Veteran Affairs Medical Center
Michael AJ Sawyer, MD, Consulting Staff, Department of Surgery, Southwestern Medical Center; Consulting Staff, Department of Surgery, Comanche County Memorial Hospital; Consulting Staff, Great Plains Surgical Clinic, Inc; Robert A Decker, MD, Clinical Assistant Professor, Department of Medicine, University of Hawaii at Manoa: Chief, Gastroenterology Service, Kaiser Permanente Medical Center of Honolulu

Updated: Nov 16, 2009

Introduction

Afferent loop syndrome (ALS) is a purely mechanical complication that infrequently occurs following construction of a gastrojejunostomy. Creation of an anastomosis between the stomach and jejunum leaves a segment of small bowel, most commonly consisting of duodenum and proximal jejunum, lying upstream from the gastrojejunostomy. This limb of intestine conducts bile, pancreatic juices, and other proximal intestinal secretions toward the gastrojejunostomy and is thus termed the afferent loop.

Afferent limb syndrome. Kinking of the afferent limb at the gastrojejunostomy.

Afferent limb syndrome. Tracing of kinking of the afferent limb at the gastrojejunostomy.

History of the Procedure

The operations most commonly associated with this complication include distal or subtotal gastrectomies for peptic ulcer disease or gastric malignancies with Billroth II reconstructions, pancreaticoduodenectomies, and gastrojejunostomies performed to bypass other foregut pathology. The pathophysiology and signs and symptoms associated with ALS result from partial or complete obstruction of the afferent loop.

ALS is included in the constellation of resectional gastric surgical complications known as the postgastrectomy syndromes. The following syndromes are included:

• Early dumping syndrome¹
• Late dumping syndrome²
• Postvagotomy diarrhea³
• Chronic gastric atony⁴
• Roux stasis syndrome⁵
• Small gastric remnant syndrome⁶
• Alkaline reflux gastritis⁷
• Afferent loop syndrome⁸
• Efferent loop syndrome⁸

Patients with ALS may present with an acute, completely obstructed form or with a chronic, partially obstructed form. The syndrome can manifest at any time from the first postoperative day to many years after surgery. The acute form usually occurs in the early postoperative period (1-2 wk), but it has been described to occur 30-40 years after surgery.

In 1942, McNealy first described acute ALS as a cause of early postoperative duodenal stump leakage. Lake is credited with recognizing the chronic form in 1948. Roux and coworkers coined the term afferent loop syndrome in 1950.⁹ The first detailed exegesis in the English literature on the etiology, clinical presentation, and treatment of ALS was contributed by Wells and Welbourn in 1951.¹⁰

Problem

ALS manifests in acute and chronic forms. Acute ALS represents complete obstruction of the afferent loop and is a true surgical emergency. It must be diagnosed and corrected expeditiously. Chronic ALS is associated with partial obstruction. It is not a surgical emergency but does require corrective surgery.

Frequency

In the United States, ALS affects approximately 1% of patients undergoing gastric resection and Billroth II gastrojejunostomies. This figure may be an underestimation because this complication is probably underdiagnosed. Overall, the incidence of this complication decreased dramatically during the final quarter of the 20th century as elective gastric surgery for complications of peptic ulcer disease underwent a logarithmic decline.^11,12

Internationally, rates for the development of this complication appear to be similar in other nations.

Mortality/Morbidity: Mortality rates of up to 57% have been reported for acute ALS. Mortality is most frequently associated with a delay in diagnosis that leads to bowel infarction or rupture and peritonitis. Patients in whom a timely diagnosis is made or who present with chronic manifestations of the disease can undergo corrective surgery with acceptably low morbidity and mortality rates.

Sex: According to Tovey et al, one or more of the postgastrectomy syndromes is more likely to occur in female patients.¹³

Age: ALS favors no particular age group on a per capita basis.

Etiology

Postoperative conditions

Each of the following postoperative conditions can cause ALS in a patient with a gastrojejunostomy:

• Entrapment or compression of the afferent loop by postoperative adhesions
• Internal hernia (eg, through a mesocolic defect)¹⁴
• Volvulus of the intestinal segment
• Enteroenteral or enterogastric intussusception
• Kinking of the afferent limb at the gastrojejunostomy (see Media files 1-2)
• Scarring due to marginal (stomal) ulceration¹⁵
• Recurrence of cancer at or near the anastomotic site
• Enteroliths in the afferent limb¹⁶
• Bezoars in the afferent limb or at the anastomosis¹⁷
• Foreign bodies in the afferent limb or at the anastomosis

Surgical technique

Patients have an increased chance of developing ALS if one or more of the following conditions is met:

• The jejunal portion of the afferent limb is longer than 30-40cm in length.
• The gastrojejunostomy is placed in an antecolic position instead of a retrocolic position.
• Mesocolic defects are not properly closed after construction of a retrocolic gastrojejunostomy.

Bushkin and Woodward reported an equal incidence of ALS in patients with short, retrocolic afferent limbs.¹⁸ However, according to Eagon and coworkers, most authors opine that longer, redundant, and antecolic afferent limbs are more prone to kinking, volvulus, and entrapment by adhesions.⁸

Pathophysiology

An afferent loop is composed of the duodenal stump, the remainder of the duodenum, and the segment of jejunum located proximal to a Billroth II–type gastrojejunostomy. ALS is caused by complete or partial mechanical obstruction at the gastrojejunostomy or at a point along the jejunal portion of the afferent loop.

Passage of food and gastric secretions through the gastrojejunostomy and into the efferent loop triggers release of secretin and cholecystokinin. These enteric hormones stimulate secretion of bile, pancreatic enzymes, and pancreatic bicarbonate and water into the afferent loop. Under gastrointestinal hormonal influence, up to 1-2 L of pancreatic and biliary secretions can enter the afferent loop each day.

Symptoms associated with ALS are caused by increased intraluminal pressure and distention due to accumulation of enteric secretions in a partially or completely obstructed afferent limb. ALS is one of the main causes of duodenal stump blowout in the early postoperative period and is also an etiology for postoperative obstructive jaundice, ascending cholangitis, and pancreatitis due to transmission of high pressures back to the biliopancreatic ductal system.¹⁹ High luminal pressures and distention increase bowel wall tension in the afferent loop (in accord with the Laplace law) and can lead to ischemia and gangrene with subsequent perforation and peritonitis.

Secondarily, prolonged stasis and pooling of secretions with partial obstruction facilitate bacterial overgrowth in the afferent loop.²⁰ Bacteria deconjugate bile acids, which can lead to steatorrhea, malnutrition, and vitamin B-12 deficiency leading to megaloblastic anemia. 

A variety of investigations have been performed to confirm a diagnosis of bacterial overgrowth and include jejunal aspiration, 14 carbon D-xylose breath testing, hydrogen breath testing using glucose or galactose, and 14 carbon-glycocholic breath testing. However, as none of these investigations have been standardized, treatment is often initiated clinically when there is a high index of suspicion. Although the mechanism behind iron deficiency is complex, iron deficiency can also develop due to bypassing of the proximal small bowel and achlorhydria which impairs iron solubility.

The severity at presentation mainly depends on the degree and duration of obstruction.

Presentation

History - Acute ALS

Acute ALS is caused by complete obstruction of the afferent loop. However, it is rare and may either occur within a few days postoperatively or present unexpectedly several years after a Billroth II gastrectomy as described by Ballas et al.²¹ In both circumstances, this condition is caused by acute obstruction of the afferent limb due to herniation or volvulus of the afferent loop posterior to the efferent limb. Patients with acute ALS typically present with a sudden onset of epigastric and/or right or left upper quadrant abdominal pain, with associated nausea and vomiting.

With acute ALS, the vomitus is not bilious because the biliary and pancreatic secretions remain trapped in the obstructed bowel loop. If the afferent loop is not decompressed, the patient becomes acutely ill and can subsequently develop peritonitis and shock if intestinal perforation or infarction ensues.

History - Chronic ALS

Chronic ALS is caused by partial obstruction of the afferent loop and may be more difficult to diagnose than acute ALS. Approximately 10-20 minutes to an hour postprandially, the patient experiences abdominal fullness and epigastric pain. These symptoms usually last from several minutes to an hour, although they occasionally last as long as several days.

Projectile bilious vomiting is a classic manifestation of ALS with partial obstruction. The distended afferent loop decompresses forcefully, providing rapid relief of symptoms. Note that the vomitus usually contains no food because it has progressed along the unobstructed efferent limb. Vomiting may occur after each meal or only occasionally.²² Also, symptoms in the immediate postprandial period may be minimized if the patient assumes a recumbent position.

Prolonged chronic ALS with stasis and bacterial overgrowth can be further complicated by steatorrhea, diarrhea, and vitamin B-12 deficiency anemia. These effects are primarily due to bacterial deconjugation of bile salts. The aforementioned factors, in addition to bypassing the duodenum and proximal jejunum, can result in iron deficiency anemia.

Physical examination can reveal one or more of the following findings:

• An ill-defined mass in the right upper abdominal quadrant may be present in one-third of patients with acute ALS.
• Localized midepigastric or right upper abdominal quadrant tenderness
• Peritonitis and/or a rigid abdomen if necrosis or perforation of the bowel wall has occurred
• Jaundice
• Signs of pancreatitis (eg, upper abdominal pain radiating to the flank or back

• Abdominal abscess
• Abdominal hernias
• Acute mesenteric ischemia
• Anemia
• Bacterial overgrowth syndrome
• Benign gastric tumors
• Benign neoplasm of the small intestine
• Bile duct strictures
• Bile duct tumors
• Biliary colic
• Biliary obstruction
• Carcinoma of the ampulla of Vater
• Choledochal cysts
• Choledocholithiasis
• Esophagogastroduodenoscopy
• Gastric outlet obstruction
• Gastric sarcoma
• Gastric ulcers
• Gastric volvulus
• Gastritis (acute, atrophic, or chronic)
• Intestinal perforation
• Mesenteric artery ischemia
• Mesenteric artery thrombosis
• Mesenteric tumors
• Omental torsion

Other problems to be considered

• Bile reflux gastritis
• Pancreatic pseudocyst or cystic tumor
• Mesenteric cyst
• Mesenteric lymphoid hamartoma
• Intra-abdominal abscess
• Cystic metastases

Indications

Surgery is indicated in most cases of ALS. Recently, successful management of ALS in cases of advanced or recurrent malignancy using image-directed percutaneous drainage techniques has been reported. The fact remains that ALS is a purely mechanical complication consisting of varying degrees of obstruction of the afferent loop and will not resolve without surgery or other interventional techniques.

Relevant Anatomy

The afferent loop consists of the duodenal stump, the remainder of the duodenum, and the segment of jejunum proximal to the gastrojejunostomy. The clinically relevant portion of the loop pertaining to ALS is the jejunal portion of the afferent limb. The jejunal limb is subject to adhesion formation, internal herniation, volvulus, anastomotic obstruction, and other etiologies of ALS, as previously described.

Contraindications

Surgical correction of ALS has no absolute contraindications. Relative contraindications include severe debilitation or extensive intra-abdominal malignancies. Patients with these conditions can be effectively treated with nonsurgical drainage procedures as described in Treatment.

Workup

Laboratory Studies

• CBC count
  • Blood should be drawn for a CBC count. Areas of interest include the hemoglobin and hematocrit values, WBC count, and RBC characteristics (eg, mean corpuscular volume, cell size, iron content).
  • These studies aid in confirming the diagnosis of anemia (hemoglobin and hematocrit), the possibility of infection or acute illness (WBC count), and a possible cause for anemia related to ALS (eg, vitamin B-12 deficiency anemia, iron deficiency anemia).
• LFTs and pancreatic enzymes
  • Elevated levels of serum bilirubin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, amylase, and lipase may be detected when biliary tract obstruction is prominent.
  • Occasionally, abnormalities of these hepatic and pancreatic products are early clues to the diagnosis in the proper patient scenario (eg, those with a Billroth II gastrojejunostomy).
• Electrolyte panel
  • Serum electrolytes should be examined, especially in patients with prolonged vomiting and possible dehydration.
  • These conditions can lead to hyponatremia or hypernatremia, hypokalemia, and hypochloremia. Metabolic alkalosis may be present.
• Albumin
  • Serum albumin levels should be measured, especially because ALS requires surgical correction.
  • In patients with chronic ALS and significant malnutrition, a period of preoperative specialized nutritional support might be appropriate.
• Carbon 14 xylose breath test
  • When bacterial overgrowth is present, a carbon 14 xylose breath test reveals an increased concentration of hydrogen in exhaled gas following a glucose-containing meal.
  • This test is mainly helpful in diagnostic dilemmas and has no role in acute ALS.

Imaging Studies

• Imaging studies may be of greater utility in patients with chronic ALS in which the diagnosis is often elusive. Although imaging tests are often performed in patients with acute ALS, the vast majority of such patients require urgent surgery regardless of the results of imaging tests.
• Upper gastrointestinal series: Findings from an upper gastrointestinal series may suggest the diagnosis when orally administered contrast agents fail to provide adequate opacification of the afferent loop. However, test results are not specific because nonopacification of the afferent loop is not unusual in normally functioning Billroth II anastomoses.
• Abdominal ultrasonography
  • Ultrasound may demonstrate a peripancreatic cystic mass or a fluid-filled tubular structure in the right upper abdominal quadrant that may cross the midline.
  • Kitamura and associates performed ultrasound as an adjunct to percutaneous small bowel drainage in patients with ALS.²³ They used ultrasound to identify a segment of the afferent limb in apposition to the abdominal wall in 3 patients with ALS. In each case, the small bowel segment was successfully cannulated and decompressed.
  • Derchi and colleagues reported their experience with ultrasound in 4 patients with ALS caused by tumor recurrence at or near a Billroth II gastrojejunostomy.²⁴ In each case, ultrasound was able to define the distended afferent limb as a fluid-filled structure with a multilayered wall and effacement of the mucosal folds. The investigators described being able to trace the obstructed afferent loop from the hepatic hilum to the anastomosis with the stomach.
  • Lee and coworkers reviewed the sonographic findings of ALS in 7 patients.²⁵ In their group of patients, the etiology for ALS was internal herniation in 3, recurrent cancer in 2, marginal ulceration in 1, and a new primary cancer at the anastomosis in 1. The obstructed afferent limb appeared as a dilated, fluid-filled structure in the upper abdominal quadrants, which crossed the midline. These investigators also described the ability to trace this distended bowel loop to the area of the gastrojejunostomy.
  • Matsusue and colleagues published their experience with ultrasound in 3 patients with ALS.²⁶ In their report, the salient features of ALS on ultrasound images included a dilated intestinal loop without accompanying gas echoes in the upper abdomen and associated echolucent, edematous swelling of the pancreas.
• Hepatobiliary scintigraphy: These investigations have been used with limited success in diagnosing chronic ALS. Normally, the radionuclide should pass from the afferent limb into the stomach or distal small bowel. Failure to do so may suggest the possibility of an afferent loop obstruction, although the medical usefulness of these studies remains to be determined.
• Muthukrishnan and colleagues used technetium-99m (^99m Tc) mebrofenin hepatobiliary scintigraphy to examine 2 patients with gastrojejunostomies who presented with bilious vomiting.²⁶ Findings from previous studies, including endoscopy and ultrasonography, had been nondiagnostic. The scintigraphic technique identified duodenal and extrahepatic biliary dilation in these patients, consistent with chronic ALS
• Lai and coworkers performed^99m Tc hepatoiminodiacetic acid scanning on a patient with a gastrojejunostomy and obstructive jaundice.²⁷ The main findings included a dilated afferent loop and dilated biliary radicles.
• Sivelli and colleagues reported their experience with^99m Tc hepatoiminodiacetic acid scanning in 50 patients with Billroth II gastrojejunostomies and postgastrectomy syndromes.²⁸ Based on clinical findings, 18 of these patients were thought to have ALS. In this subgroup, abnormal afferent loop emptying was demonstrated in 8 and atonic gallbladder distension without afferent loop abnormalities was found in 10. The authors stressed that clinical symptoms associated with ALS are not pathognomonic and that hepatobiliary scintigraphy can aid in the differential diagnosis of ALS and other conditions such as biliary dyskinesia.
• Abdominal CT scanning
  • Abdominal CT scanning helps visualize the obstructed segment directly and yields detailed information regarding the biliary tree, pancreas, and other structures. Yilmaz et al reported that CT scanning should be the radiographic study of choice in the diagnosis of ALS.²⁹
  • Zissin and coworkers reported salient CT scan features of ALS.³⁰ They described the typical appearance as that of a U-shaped, fluid-filled tubular structure crossing the midline of the abdomen between the abdominal aorta and the superior mesenteric artery.
  • Kim and coauthors demonstrated the accuracy of CT scanning not only in detecting ALS but also in predicting the underlying pathology causing the condition.³¹ They performed helical CT scans on 18 patients presenting with ALS. CT scanning helped correctly predict locally recurrent gastric cancer or carcinomatosis as the cause in 16 patients and adhesion formation and internal herniation as the cause in the other 2 patients.
  • Gayer and colleagues described CT scan findings in 5 patients with ALS.³² The afferent limb appeared as a dilated (average 5.3 cm diameter), fluid-filled tubular mass. Valvulae conniventes were observed in all cases, and intraluminal air was detected in 80%. The dilated loop was confined to the subhepatic area in 60%, but it crossed the midline in the other patients. Biliary dilation was identified in all patients, and radiographic evidence of pancreatitis was discovered in one. Notably, orally administered contrast opacified the afferent limb in just one patient.
  • Gale and coworkers stated that the afferent limb can appear as multiple, uniformly sized, peripancreatic cystic masses on CT scans.³³ This description was confirmed by Swayne and Love, who added that the cysts featured attenuation numbers consistent with water density.³⁴
  • The initial description of ALS on CT scans was offered by Kuwabara and associates in 1980.³⁵ They characterized an obstructed afferent limb as a U-shaped cystic mass in continuity with the biliary system, appearing posterior to the superior mesenteric artery.
• Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP)
  • Chevallier and associates described a case of a 77-year-old man presenting with obstructive jaundice.³⁶ MRI revealed biliary and pancreatic ductal dilation and a dilated afferent limb. A mass was visualized between the afferent loop and gastric remnant. Endoscopy with biopsy proved this mass to be an adenocarcinoma that was completely obstructing the afferent limb.
  • A variety of investigators have used MRCP to diagnose ALS.^37,38 For example, McKee and coworkers described the use of MRCP in ALS manifesting with cholangitis.³⁷
• Plain abdominal radiography: Plain abdominal radiographs can be helpful by demonstrating abnormal bowel gas patterns or air-fluid levels, but these findings are not specific to the diagnosis of ALS.

Diagnostic Procedures

• Upper endoscopy
  • Esophagogastroduodenoscopy offers the advantage of direct visualization of the gastrojejunostomy and portions of its afferent and efferent limbs. The anastomosis can be inspected for kinking or marginal ulceration. A twist near the anastomosis suggests volvulus or internal herniation. Worrisome masses in the region of the anastomosis can be identified, and biopsy samples can be taken. In addition, enteroliths may also be present, which may mimic mitotic disease on imaging studies and can only be diagnosed with upper endoscopy as described by Yavuz et al.³⁹
  • According to Eagon et al, esophagogastroduodenoscopy is helpful in discriminating between ALS and alkaline reflux gastritis, which is an important entity in the differential diagnosis.⁸
• Radiographically guided interventional techniques
  • The cornerstone of treatment in ALS remains corrective surgery. Occasionally, patients are too debilitated to withstand operative therapy or recurrent cancer may preclude a successful reoperation.
  • In 2002, Kim and associates published their results with palliative percutaneous tube enterostomy in patients with ALS who presented with a chief complaint of jaundice.⁴⁰ In each case, the dilated afferent loop was successfully cannulated and decompressed. Bilirubin levels returned to reference ranges in 5 (71%) of 7 patients.
  • Lee and coworkers described 2 patients with ALS due to recurrent gastric cancer who were deemed inoperable.⁴¹ Both patients underwent percutaneous transhepatic drainage of the duodenum followed by weekly infusions of 5-fluorouracil and leucovorin. In both cases, afferent limb patency was reestablished, and drainage catheters were subsequently removed. At the time of the report, the patients remained free of symptoms 16 and 17 months after drainage, respectively.
  • Caldicott and associates published the case report of a man who had undergone partial gastrectomy and later presented with distal common bile duct and duodenal obstruction due to an inoperable carcinoma of the head of the pancreas.⁴² Using percutaneous transhepatic techniques, the patient was effectively palliated by placement of metallic stents across the biliary and duodenal strictures.
  • Yoshida and coauthors reported the case of a 77-year-old man presenting with fever, right upper quadrant abdominal pain, and jaundice 2 years after a distal gastrectomy for cancer.⁴³ CT scanning revealed a dilated afferent limb and intrahepatic biliary tree. ALS secondary to recurrent gastric cancer was diagnosed. The authors accessed the afferent limb via the ampulla of Vater, using percutaneous transhepatic biliary drainage techniques. One week after the initial drainage, a sheath introducer was inserted distal to the point of obstruction, and the stenotic area was successfully reopened with metallic stents. A double pigtail catheter was also deployed to prevent stent migration. The same investigators further refined the above technique for afferent loop obstruction caused by recurrent gastric carcinoma.⁴⁴ They simultaneously deployed an expandable metal biliary stent percutaneously together with a double-pigtail catheter endoscopically to prevent migration of the metal stent.
  • Chevallier and colleagues described a patient in whom a malignant distal afferent loop obstruction developed 19 months after undergoing pancreaticoduodenectomy with Roux-en-Y reconstruction for pancreatic cancer.⁴⁵ The obstruction was too distal to be palliated via stent deployment via the transbiliary route. Successful palliation was achieved by percutaneous jejunostomy and stenting.
  • Song et al reported their experience with metallic stents in 39 consecutive patients who had undergone gastrojejunostomy.⁴⁶ The investigators reported that although placement of these stents was technically successful in 90% of patients, stent migration was more common in fully covered stents (4 of 24 cases) compared with no migration in the bare or partially covered stents. In addition, recurrent ALS occurred 10 days after stent placement in 1 patient. Tumor ingrowth occurred in 1 of 4 bare stents and tumor overgrowth in 1 of 29 partially covered stents requiring a second metal stent.

Treatment

Medical Therapy

Acute ALS

In patients with acute ALS, a favorable outcome is correlated with an expedient diagnosis and corrective surgery. Medical therapy has no role, although nasogastric tube drainage may temporarily provide relief of symptoms while patients are resuscitated before surgery. Kim et al reported a case of a 67-year-old patient with ALS and coexisting acute pancreatitis who was not felt to be an ideal surgical candidate.⁴⁷ As a result, the patient was treated with an endoscopically placed nasogastric/enteric tube, with excellent relief of symptoms.

Chronic ALS

Patients with chronic ALS can be severely malnourished and anemic. These patients may benefit from preoperative specialized nutritional support or transfusion before undergoing corrective surgery. However, surgery should not be delayed if symptoms and signs consistent with complete obstruction develop.

Surgical Therapy

The treatment of ALS is surgical. Conservative measures can be temporarily used to resuscitate the patient, but the definitive treatment is corrective surgery. When ALS is caused by recurrent or unresectable malignancies, successful palliation is frequently accomplished using interventional radiologic techniques. Several references are described in the preceding section.

Surgical correction is effected by deconstructing the Billroth II gastrojejunostomy and restoring gastrointestinal continuity with an alternate method. Several procedures have been described, but the 2 predominant operations are Billroth I gastroduodenostomy and Roux-en-Y gastrojejunostomy.

Interestingly, based on their retrospective study of 19 patients with postgastrectomy syndromes of whom 3 had ALS, Borrelli et al reported a significant proportion of patients required minor surgical intervention.⁴⁸ The authors raised the question that in selected patients, laparoscopic surgery may be considered.

Vettoretto and associates reported a case of afferent loop obstruction caused by an adhesive band following distal gastrectomy and reconstruction for gastric cancer.⁴⁹ The authors performed diagnostic laparoscopy and laparoscopic lysis of adhesions, resulting in resolution of the ALS.

Aimoto and colleagues described 2 cases of malignant ALS in patients who had undergone pancreaticoduodenectomy.⁵⁰ In both patients, recurrence of pancreatic cancer was found at laparotomy. Bypass procedures were performed in each case to effect palliation.

Consultations: Early consultation with a surgeon is mandatory.

Preoperative Details

The patient is properly identified. The patient (or a legal representative) is counseled about the operation and signs the informed consent documents.

Intravenous access is established, and intravenous fluid resuscitation is begun. A nasogastric tube is placed to decompress the stomach, and preoperative antibiotics are administered.

Intraoperative Details

Billroth I gastroduodenostomy

This procedure creates a direct anastomosis between the stomach and duodenum. It is the most physiologic procedure and is therefore the operation of choice. Several factors may preclude its use, including previous subtotal gastrectomy or extensive scarring around the duodenum. In these situations, the surgeon may be unable to gain enough mobility on the stomach and duodenum to create an anastomosis without excessive tension.

Roux-en-Y gastrojejunostomy

For a Roux-en-Y gastrojejunostomy, the jejunum is divided several centimeters distal to the ligament of Treitz. The proximal portion of the distal jejunal segment is anastomosed to the stomach. The distal end of the Roux limb is anastomosed to the distal jejunal segment. This jejunojejunostomy is created approximately 40 cm downstream from the gastrojejunostomy in order to minimize the possibility of developing alkaline (bile) reflux gastritis.

Van Stiegmann and Goff described a variant of this operation in which the jejunum is not divided.⁵¹ This is the so-called uncut Roux-en-Y gastrojejunostomy. The procedure was developed to avoid Roux stasis syndrome, which was thought to be caused by interruption of jejunal intestinal pacesetting potentials.

In an uncut Roux procedure, a loop gastrojejunostomy is fashioned. The afferent limb of this loop is occluded—but not divided—by a staple line. A jejunojejunostomy is made between the afferent and efferent jejunal limbs just proximal to the occluding staple line. This operation has not gained wide acceptance, partially because of the problem of dehiscence of the occluding staple line, as reported by Mulholland and colleagues.⁵²

Other surgical procedures

The following remedial operations have also been used:

• Revision of the gastrojejunostomy
• Side-to-side enteroenterostomy
• Jejunal segment interposition (between the gastric remnant and duodenum to create a modified Billroth I–type anastomosis)
• Resection of the redundant portion of the afferent jejunal loop

Postoperative Details

Intravenous fluids

Resuscitative and maintenance intravenous fluids are provided postoperatively. These are usually administered as a balanced salt solution (eg, lactated Ringer solution). If the patient has hypochloremic metabolic alkalosis due to nasogastric suctioning or other causes, normal saline can be substituted. Intravenous fluid support is continued until the patient successfully resumes oral intake.

Activity

Early activity, including arising from the bed to a chair and ambulating frequently, is encouraged.

Diet and nutrition

Patients are kept nil per os (NPO) for varying durations depending on the preference of the operating surgeon. Because correction of ALS entails reoperative gastric and small bowel surgery, many surgeons choose to advance patients slowly.

Following nasogastric tube removal, patients can be started on liquids and advanced to a full diet as tolerated. Postgastrectomy diet counseling by a registered dietitian is helpful. Patients may find that they tolerate 5-6 smaller feedings per day better than the traditional 3 meals.

Depending on the patient's preoperative nutritional status, a period of specialized nutritional support might be warranted. This can range from enteral tube feedings to peripheral hyperalimentation to total parenteral nutrition. In addition, multivitamin and iron supplementation may be indicated.

Drains

A nasogastric tube is typically left in place postoperatively. Ensuring that the tube functions continuously and remains unclogged is crucial. Criteria for removal of a nasogastric tube include diminishing output and return of bowel function as manifested by bowel sounds or the passage of flatus.

A Foley catheter remains in place in the early postoperative period to monitor hydration status and to serve as a guide for fluid resuscitation. Once the patient is stabilized and no further major fluid shifts occur, the catheter can be removed.

Pulmonary toilet

Instruct patients to cough and to take frequent deep breaths. The incentive spirometer is an important adjunct and should be used every 1-2 hours while the patient is awake. Early mobilization of the patient assists with maintaining good pulmonary toilet.

Monitoring

Vital signs are monitored per protocol. Intake and output records are kept to monitor intravenous fluids given, oral intake, and urine and nasogastric tube outputs. Pulse oximetry may be used to measure oxygen saturation.

Antibiotics

Unless bowel perforation has occurred, a single dose of antibiotics as prophylaxis against wound infection usually suffices. Patients with abdominal catastrophes, such as bowel perforation or infarction, require a full course of antibiotic therapy aimed at gut flora.

Pain control

An epidural catheter can be placed by anesthesia personnel for postoperative pain control. Alternately, a patient-controlled anesthesia regimen can be ordered.

Deep venous thrombosis prophylaxis

Prophylaxis against deep venous thrombosis is crucial because deep venous thrombosis and pulmonary embolism are significant sources of postoperative morbidity and mortality. Available modalities include subcutaneous heparin, subcutaneous fractionated heparin preparations, and sequential compression stockings.

Aspiration precautions

The head of the bed can be kept elevated at 30-45° or sometimes higher in elderly patients or during sleep.

Follow-up

The operating surgeon should monitor patients to ensure that wound healing is complete and that no signs of infection arise. Patients are questioned about eating and elimination habits and are weighed to ensure that proper nutritional status is maintained.

Gastric emptying

Patients with persistent delayed gastric emptying or gastroparesis may report early satiety, epigastric fullness, nausea, or vomiting. Abdominal pain may be present. According to Gustavsson and associates, up to 30% of patients undergoing revision with a Roux-en-Y gastrojejunostomy develop one or more of these symptoms.⁵ This has been termed Roux stasis syndrome.

The workup for Roux stasis syndrome or simple gastric atony begins with upper gastrointestinal contrast studies to exclude a source of mechanical obstruction. Upper endoscopy can help determine if the patient has a mechanical problem (eg, anastomotic stricture). Radionuclide imaging is useful to confirm the diagnosis.

Conversely, patients may develop signs and symptoms of dumping syndrome following corrective surgery. While the diagnosis is primarily made based on clinical findings, radionuclide imaging helps confirm the diagnosis by demonstrating rapid gastric emptying.

Treating altered gastric emptying

For delayed gastric emptying, agents such as erythromycin and metoclopramide have been used with varying degrees of success. Patients with dumping syndrome can be given a low-carbohydrate diet and are instructed to limit fluid intake during meals. A somatostatin analog administered before meals has been successful in controlling dumping-related symptoms.

Hematopoiesis

CBC count and RBC characteristics are monitored. Patients with loss of parietal cell mass and bypass of the proximal small bowel may require supplemental iron and vitamin B-12.

Complications

Patients undergoing surgery for ALS are at risk for developing any of the following complications:

• Wound infection
• Wound dehiscence with or without evisceration
• Urinary tract infection
• Atelectasis
• Pneumonia
• Anastomotic disruption
• Anastomotic stricture
• Marginal ulceration
• Intra-abdominal abscess formation
• Cholangitis
• Delayed gastric emptying/gastroparesis
• Internal or enterocutaneous fistulae
• Small bowel obstruction
• Dumping syndrome
• Alkaline reflux gastritis
• Roux stasis syndrome
• Cardiac arrhythmias
• Deep venous thrombosis
• Pulmonary embolism

Outcome and Prognosis

After a proper corrective procedure, the prognosis is usually very good, except in cases of advanced or recurrent malignancy.

Future and Controversies

Medicolegal pitfalls

The major medicolegal pitfall associated with ALS is a delay in diagnosis. This is most serious with acute ALS because diagnostic delay can lead to bowel perforation or gangrene with resultant intra-abdominal sepsis.

Multimedia

Media file 1: Afferent limb syndrome. Kinking of the afferent limb at the gastrojejunostomy.

Media file 2: Afferent limb syndrome. Tracing of kinking of the afferent limb at the gastrojejunostomy.

Media file 3: Afferent limb syndrome. Normal anatomy and Billroth II gastrojejunostomy.

Media file 4: Afferent limb syndrome. Roux-en-Y gastrojejunostomy.

References

1. Roberts KE, Randall HT, Farr HW, Kidwell AP, Mcneer GP, Pack GT. Cardiovascular and blood volume alterations resulting from intrajeunal administration of hypertonic solutions to gastrectomized patients: the relationship of these changes to the dumping syndrome. Ann Surg. Nov 1954;140(5):631-40. [Medline].

2. Shultz KT, Neelon FA, Nilsen LB, Lebovitz HE. Mechanism of postgastrectomy hypoglycemia. Arch Intern Med. Aug 1971;128(2):240-6. [Medline].

3. Emas S, Fernstrom M. Prospective, randomized trial of selective vagotomy with pyloroplasty and selective proximal vagotomy with and without pyloroplasty in the treatment of duodenal, pyloric, and prepyloric ulcers. Am J Surg. Feb 1985;149(2):236-43. [Medline].

4. Hom S, Sarr MG, Kelly KA, Hench V. Postoperative gastric atony after vagotomy for obstructing peptic ulcer. Am J Surg. Mar 1989;157(3):282-6. [Medline].

5. Gustavsson S, Ilstrup DM, Morrison P, Kelly KA. Roux-Y stasis syndrome after gastrectomy. Am J Surg. Mar 1988;155(3):490-4. [Medline].

6. Delcore R, Cheung LY. Surgical options in postgastrectomy syndromes. Surg Clin North Am. Feb 1991;71(1):57-75. [Medline].

7. Ritchie WP Jr. Alkaline reflux gastritis. An objective assessment of its diagnosis and treatment. Ann Surg. Sep 1980;192(3):288-98. [Medline].

8. Eagon JC, Miedema BW, Kelly KA. Postgastrectomy syndromes. Surg Clin North Am. Apr 1992;72(2):445-65. [Medline].

9. Roux G, Pedoussaut R, Marchal G. [Afferent loop syndrome of gastrectomized subjects.]. Lyon Chir. Oct 1950;45(7):773-80. [Medline].

10. Wells C, Welbourn R. Post-gastrectomy syndromes; a study in applied physiology. Br Med J. Mar 17 1951;1(4706):546-54. [Medline].

11. Burkhalter E. Incidence of gastrectomy in United States army hospitals worldwide from 1975 to 1985. Am J Gastroenterol. Nov 1988;83(11):1231-4. [Medline].

12. Paimela H, Tuompo PK, Perakyl T, Saario I, Hockerstedt K, Kivilaakso E. Peptic ulcer surgery during the H2-receptor antagonist era: a population-based epidemiological study of ulcer surgery in Helsinki from 1972 to 1987. Br J Surg. Jan 1991;78(1):28-31. [Medline].

13. Tovey FI, Godfrey JE, Lewin MR. A gastrectomy population: 25-30 years on. Postgrad Med J. Jun 1990;66(776):450-6. [Medline].

14. Ogata M, Ishikawa T. Acute afferent loop obstruction caused by retroanastomotic hernia. J Ultrasound Med. Nov 1993;12(11):697-9. [Medline].

15. Tsutsui S, Kitamura M, Shirabe K, Baba H, Sugimachi K. Afferent loop syndrome due to scarring of a stomal ulcer following a Billroth II gastrectomy. Endoscopy. Jun 1995;27(5):410. [Medline].

16. Carbognin G, Biasiutti C, El-Khaldi M, Ceratti S, Procacci C. Afferent loop syndrome presenting as enterolith after Billroth II subtotal gastrectomy: a case report. Abdom Imaging. Mar-Apr 2000;25(2):129-31. [Medline].

17. Hui MS, Perng HL, Choi WM, Chem LK, Yang KC, Chen TJ. Afferent loop syndrome complicated by a duodenal phytobezoar after Billroth-II subtotal gastrectomy. Am J Gastroenterol. Sep 1997;92(9):1550-2. [Medline].

18. Bushkin FL, Woodward ER. The afferent loop syndrome. Major Probl Clin Surg. 1976;20:34-48. [Medline].

19. Locke GR, Alexander GL, Sarr MG. Obstructive jaundice: an unusual presentation of afferent loop obstruction. Am J Gastroenterol. Jun 1994;89(6):942-4. [Medline].

20. Rana SV, Bhardwaj SB. Small intestinal bacterial overgrowth. Scand J Gastroenterol. 2008;43(9):1030-7. [Medline].

21. Ballas KD, Rafailidis SE, Konstantinidis HD, et al. Acute afferent loop syndrome: a true emergency. A case report. Acta Chir Belg. Jan-Feb 2009;109(1):101-3. [Medline].

22. Golioto M. A woman with abdominal pain and bilious vomiting. A very late aftermath of Billroth II gastrectomy. N C Med J. Nov-Dec 2000;61(6):338-40. [Medline].

23. Kitamura H, Miwa S, Nakata T, Nomura K, Tanaka T, Ikegami T, et al. Sonographic detection of visceral adhesion in percutaneous drainage of afferent-loop small-intestine obstruction. J Clin Ultrasound. Mar 2000;28(3):133-6. [Medline].

24. Derchi LE, Bazzocchi M, Brovero PL. Sonographic diagnosis of obstructed afferent loop. Gastrointest Radiol. 1992;17(2):105-7. [Medline].

25. Lee DH, Lim JH, Ko YT. Afferent loop syndrome: sonographic findings in seven cases. AJR Am J Roentgenol. Jul 1991;157(1):41-3. [Medline].

26. Matsusue S, Kashihara S, Takeda H, Koizumi S. Three cases of afferent loop obstruction--the role of ultrasonography in the diagnosis. Jpn J Surg. Nov 1988;18(6):709-13. [Medline].

27. Lai FM, Paramsothy M, George J, Yip CH. The role of 99mtechnetium (Tc) diethyl-iminodiacetic acid (EHIDA) hepatobiliary scintigraphy in the diagnosis of a rare cause of obstructive jaundice. Singapore Med J. Jun 1996;37(3):261-3. [Medline].

28. Sivelli R, Farinon AM, Sianesi M, Percudani M, Ugolotti G, Calbiani B. Technetium-99m HIDA hepatobiliary scanning in evaluation of afferent loop syndrome. Am J Surg. Aug 1984;148(2):262-5. [Medline].

29. Yilmaz S, Yekeler E, Dural C, et al. Afferent loop syndrome secondary to Billroth II gastrojejunostomy obstruction: Multidetector computed tomography findings. Surgery. Apr 2007;141(4):538-9. [Medline].

30. Zissin R, Hertz M, Paran H, Osadchy A, Gayer G. Computed tomographic features of afferent loop syndrome: pictorial essay. Can Assoc Radiol J. Apr 2005;56(2):72-8. [Medline].

31. Kim HC, Han JK, Kim KW, Kim YH, Yang HK, Kim SH, et al. Afferent loop obstruction after gastric cancer surgery: helical CT findings. Abdom Imaging. Sep-Oct 2003;28(5):624-30. [Medline].

32. Gayer G, Barsuk D, Hertz M, Apter S, Zissin R. CT diagnosis of afferent loop syndrome. Clin Radiol. Sep 2002;57(9):835-9. [Medline].

33. Gale ME, Gerzof SG, Kiser LC, Snider JM, Stavis DM, Larsen CR, et al. CT appearance of afferent loop obstruction. AJR Am J Roentgenol. Jun 1982;138(6):1085-8. [Medline].

34. Swayne LC, Love MB. Computed tomography of chronic afferent loop obstruction: a case report and review. Gastrointest Radiol. 1985;10(1):39-41. [Medline].

35. Kuwabara Y, Nishitani H, Numaguchi Y, Kamoi I, Matsuura K, Saito S. Afferent loop syndrome. J Comput Assist Tomogr. Oct 1980;4(5):687-9. [Medline].

36. Chevallier P, Gueyffier C, Souci J, Oddo F, Diaine B, Padovani B. [MRI of an afferent loop syndrome presenting as obstructive icterus]. J Radiol. Feb 2001;82(2):177-9. [Medline].

37. McKee JD, Raju GP, Edelman RR, Levine H, Steer M, Chuttani R. MR cholangiopancreatography (MRCP) in diagnosis of afferent loop syndrome presenting as cholangitis. Dig Dis Sci. Oct 1997;42(10):2082-6. [Medline].

38. Ashida A, Tamura I, Kumagiri Y, et al. Magnetic resonance cholangiopancreatography for afferent loop syndrome. ANZ J Surg. Jan-Feb 2008;78(1-2):91-2. [Medline].

39. Yavuz N, Erguney S, Ogut G, Alver O. Enteroliths developed in a chronically obstructed afferent loop coexisting with gastric remnant carcinoma: Case report and review of the literature. J Gastroenterol Hepatol. Mar 2006;21(3):495-8. [Medline].

40. Kim YH, Han JK, Lee KH, Kim TK, Kim KW, Choi BI. Palliative percutaneous tube enterostomy in afferent-loop syndrome presenting as jaundice: clinical effectiveness. J Vasc Interv Radiol. Aug 2002;13(8):845-9. [Medline].

41. Lee KD, Liu TW, Wu CW, Tiu CM, Liu JM, Chung TR, et al. Non-surgical treatment for afferent loop syndrome in recurrent gastric cancer complicated by peritoneal carcinomatosis: percutaneous transhepatic duodenal drainage followed by 24-hour infusion of high-dose fluorouracil and leucovorin. Ann Oncol. Jul 2002;13(7):1151-5. [Medline].

42. Caldicott DG, Ziprin P, Morgan R. Transhepatic insertion of a metallic stent for the relief of malignant afferent loop obstruction. Cardiovasc Intervent Radiol. Mar-Apr 2000;23(2):138-40. [Medline].

43. Yoshida H, Mamada Y, Taniai N, Kawano Y, Mizuguchi Y, Shimizu T, et al. Percutaneous transhepatic insertion of metal stents with a double-pigtail catheter in afferent loop obstruction following distal gastrectomy. Hepatogastroenterology. May-Jun 2005;52(63):680-2. [Medline].

44. Yoshida H, Mamada Y, Taniai N, et al. Afferent loop obstruction treated by percutaneous transhepatic insertion of an expandable metallic stent. Hepatogastroenterology. Sep-Oct 2008;55(86-87):1767-9. [Medline].

45. Chevallier P, Novellas S, Motamedi JP, et al. Percutaneous jejunostomy and stent placement for treatment of malignant Roux-en-Y obstruction: a case report. Clin Imaging. Jul-Aug 2006;30(4):283-6.

46. Song HY, Kim TH, Choi EK, et al. Metallic stent placement in patients with recurrent cancer after gastrojejunostomy. J Vasc Interv Radiol. Dec 2007;18(12):1538-46. [Medline].

47. Kim HJ, Kim JW, Kim KH, et al. [A case of afferent loop syndrome treated by endoscopic drainage procedure using nasogastric tube] [Korean]. Korean J Gastroenterol. Mar 2007;49(3):173-6. [Medline].

48. Borrelli D, Borrelli A, Presenti L, Bergamini C, Basili G. [Surgical approach of the functional post-partial gastrectomy syndromes] [Italian]. Ann Ital Chir. Jan-Feb 2007;78(1):3-10. [Medline].

49. Vettoretto N, Pettinato G, Romessis M, Bravo AF, Barozzi G, Giovanetti M. Laparoscopy in afferent loop obstruction presenting as acute pancreatitis. JSLS. Apr-Jun 2006;10(2):270-4. [Medline].

50. Aimoto T, Uchida E, Nakamura Y, Katsuno A, Chou K, Tajiri T, et al. Malignant afferent loop obstruction following pancreaticoduodenectomy: report of two cases. J Nippon Med Sch. Aug 2006;73(4):226-30. [Medline].

51. Van Stiegmann G, Goff JS. An alternative to Roux-en-Y for treatment of bile reflux gastritis. Surg Gynecol Obstet. Jan 1988;166(1):69-70. [Medline].

52. Mulholland MW, Magallanes F, Quigley TM, Delaney JP. In-continuity gastrointestinal stapling. Dis Colon Rectum. Sep 1983;26(9):586-9. [Medline].

53. Aerts P, Leyman P, Verellen S, Van Steenberge R. Ultrasonography and computed tomography of afferent loop obstruction. J Belge Radiol. Dec 1993;76(6):390-1. [Medline].

54. Fleser PS, Villalba M. Afferent limb volvulus and perforation of the bypassed stomach as a complication of Roux-en-Y gastric bypass. Obes Surg. Jun 2003;13(3):453-6. [Medline].

55. Kaya E, Senyürek G, Dervisoglu A, Danaci M, Kesim M. Acute pancreatitis caused by afferent loop herniation after Billroth II gastrectomy: report of a case and review of the literature. Hepatogastroenterology. Mar-Apr 2004;51(56):606-8. [Medline].

56. Lee LI, Teplick SK, Haskin PH, Sammon JK, Wolferth C, Amron G. Refractory afferent loop problems: percutaneous transhepatic management of two cases. Radiology. Oct 1987;165(1):49-50. [Medline].

57. Mann NS, Rachut E. Carcinoma of gastric stump causing afferent loop obstruction and acute pancreatitis. Hepatogastroenterology. Jan-Feb 2004;51(55):184-5. [Medline].

58. Morii Y, Arita T, Shimoda K, Yasuda K, Matsui Y, Inomata M, et al. Jejunal interposition to prevent postgastrectomy syndromes. Br J Surg. Nov 2000;87(11):1576-9. [Medline].

59. Moriura S, Takayama Y, Nagata J, Akutagawa A, Hirano A, Ishiguro S, et al. Percutaneous bowel drainage for jaundice due to afferent loop obstruction following pancreatoduodenectomy: report of a case. Surg Today. 1999;29(10):1098-101. [Medline].

60. Morse JM, Lakshman S, Thomas E. "Pseudogallbladder" appearance in partial afferent loop obstruction in a patient with cholecystectomy. South Med J. Aug 1986;79(8):1030-3. [Medline].

61. Muthukrishnan A, Shanthly N, Kumar S. Afferent loop syndrome: the role of Tc-99m mebrofenin hepatobiliary scintigraphy. Clin Nucl Med. Jun 2000;25(6):492-4. [Medline].

62. Taylor AR, Russ PD, Lee RE, Weingardt JP. Acute afferent loop obstruction diagnosed with computed tomography: case report. Can Assoc Radiol J. Aug 1999;50(4):251-4. [Medline].

63. Tien YW, Lee PH, Chang KJ. Enterolith: an unusual cause of afferent loop obstruction. Am J Gastroenterol. May 1999;94(5):1391-2. [Medline].

64. Woodfield CA, Levine MS. The postoperative stomach. Eur J Radiol. Mar 2005;53(3):341-52. [Medline].

65. Yao NS, Wu CW, Tiu CM, Liu JM, Whang-Peng J, Chen LT. Percutaneous transhepatic duodenal drainage as an alternative approach in afferent loop obstruction with secondary obstructive jaundice in recurrent gastric cancer. Cardiovasc Intervent Radiol. Jul-Aug 1998;21(4):350-3. [Medline].

66. Zissin R. CT findings of afferent loop syndrome after a subtotal gastrectomy with Roux-en-Y reconstruction. Emerg Radiol. Feb 2004;10(4):201-3. [Medline].

Keywords

afferent loop syndrome, ALS, Billroth II gastrojejunostomy, hernia, volvulus, intussusception, blind loop syndrome, proximal loop syndrome, postgastrectomy syndromes, late dumping syndrome, intestinal obstruction,

postvagotomy diarrhea, chronic gastric atony, Roux stasis syndrome, small gastric remnant syndrome, alkaline reflux gastritis, efferent loop syndrome, peptic ulcer disease, PUD, gastrojejunal loop obstruction, gastrojejunostomy, Billroth II-type gastrectomy, pancreaticoduodenectomy, esophagogastroduodenoscopy, EGD, Billroth I gastroduodenostomy, Roux-en-Y gastrojejunostomy

Contributor Information and Disclosures

Author

Sandeep Mukherjee, MB, BCh, MPH, FRCPC, Associate Professor, Department of Internal Medicine, Section of Gastroenterology and Hepatology, University of Nebraska Medical Center; Consulting Staff, Section of Gastroenterology and Hepatology, Veteran Affairs Medical Center
Sandeep Mukherjee, MB, BCh, MPH, FRCPC is a member of the following medical societies: Royal College of Physicians and Surgeons of Canada
Disclosure: Nothing to disclose.

Coauthor(s)

Michael AJ Sawyer, MD, Consulting Staff, Department of Surgery, Southwestern Medical Center; Consulting Staff, Department of Surgery, Comanche County Memorial Hospital; Consulting Staff, Great Plains Surgical Clinic, Inc
Michael AJ Sawyer, MD is a member of the following medical societies: American College of Surgeons, Society for Surgery of the Alimentary Tract, Society of American Gastrointestinal and Endoscopic Surgeons, and Society of Laparoendoscopic Surgeons
Disclosure: Nothing to disclose.

Robert A Decker, MD, Clinical Assistant Professor, Department of Medicine, University of Hawaii at Manoa: Chief, Gastroenterology Service, Kaiser Permanente Medical Center of Honolulu
Disclosure: Nothing to disclose.

Medical Editor

Rajeev Vasudeva, MD, FACG, Clinical Professor of Medicine, Consultants in Gastroenterology, University of South Carolina School of Medicine
Rajeev Vasudeva, MD, FACG is a member of the following medical societies: American College of Gastroenterology, American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, Columbia Medical Society, South Carolina Gastroenterology Association, and South Carolina Medical Association
Disclosure: Pricara Honoraria Speaking and teaching; UCB Consulting fee Consulting

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Douglas M Heuman, MD, FACP, FACG, AGAF, Chief of Hepatology, Hunter Holmes McGuire Department of Veterans Affairs Medical Center; Professor, Department of Internal Medicine, Division of Gastroenterology, Virginia Commonwealth University School of Medicine
Douglas M Heuman, MD, FACP, FACG, AGAF is a member of the following medical societies: American Association for the Study of Liver Diseases, American College of Physicians, and American Gastroenterological Association
Disclosure: Nothing to disclose.

CME Editor

Alex J Mechaber, MD, FACP, Associate Dean for Undergraduate Medical Education, Associate Professor of Medicine, University of Miami Miller School of Medicine
Alex J Mechaber, MD, FACP is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians-American Society of Internal Medicine, and Society of General Internal Medicine
Disclosure: Nothing to disclose.

Chief Editor

Julian Katz, MD, Clinical Professor of Medicine, Drexel University College of Medicine; Consulting Staff, Department of Medicine, Section of Gastroenterology and Hepatology, Hospital of the Medical College of Pennsylvania
Julian Katz, MD is a member of the following medical societies: American College of Gastroenterology, American College of Physicians, American Gastroenterological Association, American Geriatrics Society, American Medical Association, American Society for Gastrointestinal Endoscopy, American Society of Law Medicine and Ethics, American Trauma Society, Association of American Medical Colleges, and Physicians for Social Responsibility
Disclosure: Nothing to disclose.

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