What's new in gastroenterology and hepatology

The following represent additions to UpToDate from the past six months that were considered by the editors and authors to be of particular interest. The most recent What's New entries are at the top of each subsection.

ENDOSCOPY

Type of colon polypectomy snare and risk of bleeding (May 2024)

Although cold snare polypectomy (CSP) using a thin- or thick-wire snare is effective for removing small colon polyps, comparative safety data are limited. In a meta-analysis of four trials comparing the two types of snares in over 1200 CSPs, rates of intraprocedural bleeding and complete polyp resection were not significantly different between groups (bleeding: 3.1 versus 2.4 percent; complete resection: 92 versus 88 percent) [1]. No cases of delayed bleeding were reported. These data support CSP, regardless of snare type. The choice of snare is usually based on availability and endoscopist preference. (See "Management and prevention of bleeding after colonoscopy with polypectomy", section on 'Polyps <1 cm'.)

Endoscopic techniques for resection of large nonpedunculated colon polyps (April 2024)

Most large colon polyps are removed endoscopically, but the best endoscopic technique is unclear as data are limited. In a trial comparing endoscopic submucosal dissection (ESD) with endoscopic mucosal resection (EMR) in 360 patients with large (≥25 mm) nonpedunculated colon polyps, ESD reduced polyp recurrence at six months (0.6 versus 5.1 percent) [2]. However, it also resulted in higher rates of intraprocedural perforation (6 versus 2 percent) and clinically significant postprocedural bleeding (8 versus 6 percent), although the differences from EMR were not statistically significant. We use EMR to remove most large nonpedunculated polyps because they are usually benign and have low risk of recurrence. In addition, ESD requires specialized equipment, advanced training, and longer procedure times. (See "Endoscopic removal of large colon polyps", section on 'Endoscopic submucosal dissection'.)

Antibiotic prophylaxis prior to ERCP for biliary obstruction (February 2024)

For patients with biliary obstruction undergoing endoscopic retrograde cholangiopancreatography (ERCP), the benefit of antibiotic prophylaxis in all versus selected patients is uncertain. In a randomized trial including 378 patients with biliary obstruction undergoing ERCP, antibiotic prophylaxis resulted in lower risk of cholangitis compared with no prophylaxis (2 versus 6 percent) [3]. Based on these and older data, we reserve antibiotic prophylaxis for patients who are at risk for incomplete biliary drainage with ERCP and await further data before administering antibiotic prophylaxis to all patients with biliary obstruction. (See "Antibiotic prophylaxis for gastrointestinal endoscopic procedures", section on 'Endoscopic retrograde cholangiopancreatography (ERCP)'.)

Pancreatic stenting for preventing pancreatitis after ERCP (February 2024)

Patients with difficult biliary access are at increased risk for pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP), which may be prevented by prophylactic pancreatic stenting. In a trial including 1950 patients at high risk for post-ERCP pancreatitis, individuals assigned to pancreatic stent placement plus indomethacin had lower rates of post-ERCP pancreatitis compared with those assigned to indomethacin alone (11 versus 15 percent) [4]. Rates of serious adverse events were not significantly different between groups. These data support our approach of prophylactic pancreatic stenting in high-risk patients undergoing ERCP. (See "Management of difficult biliary access during ERCP in adults", section on 'Efficacy'.)

ESOPHAGEAL AND GASTRIC DISEASE

Budesonide oral suspension for eosinophilic esophagitis (March 2024)

In patients with eosinophilic esophagitis (EoE), use of topical glucocorticoids has been limited by lack of regulatory approval and potentially inconsistent drug delivery. Budesonide oral suspension is a formulation that was recently approved by the US Food and Drug Administration for treating EoE in adults and pediatric patients ages 11 years and older [5,6]. Approval was informed by clinical trials showing that topical budesonide resulted in higher rates of histologic remission and symptomatic improvement compared with placebo. We anticipate using budesonide oral suspension as the preferred topical glucocorticoid for treating EoE. (See "Treatment of eosinophilic esophagitis (EoE)", section on 'Topical glucocorticoids'.)

Dupilumab for refractory eosinophilic esophagitis (February 2024)

Few data are available on the use of dupilumab (a monoclonal antibody) for treating refractory eosinophilic esophagitis. In a cohort study of 46 patients with refractory eosinophilic esophagitis, dupilumab therapy was associated with histologic remission (defined as <15 eosinophils/high-power field) in 37 patients (80 percent) and with symptomatic improvement in 42 patients (91 percent) after a median of six months [7]. These data support our approach of using dupilumab for patients with eosinophilic esophagitis who have not responded to other therapies (eg, topical glucocorticoids). (See "Treatment of eosinophilic esophagitis (EoE)", section on 'Dupilumab'.)

HEPATOLOGY

Liver transplantation for Budd-Chiari syndrome (May 2024)

Liver transplantation may be lifesaving for patients with Budd-Chiari syndrome (BCS) who have decompensated cirrhosis or do not respond to medical therapy. However, long-term data are limited. In a study including 808 patients with BCS who underwent liver transplantation, the 1-, 5-, and 10-year rates of patient survival were 84, 77, and 68 percent, respectively, and rates of graft survival were 79, 70, and 62 percent, respectively [8]. Anticoagulation after transplantation was associated with lower risk of mortality (adjusted hazard ratio [aHR] 0.29) and graft failure (aHR 0.48) after adjusting for factors such as age, donor type, and year of transplant. These favorable outcomes support liver transplantation for selected patients with BCS. (See "Budd-Chiari syndrome: Management", section on 'Liver transplantation'.)

Hepatitis C virus antiviral treatment for patients with opioid use disorder (May 2024)

Despite concerns about adherence to antiviral therapy among individuals with opioid use disorder, hepatitis C virus (HCV) treatment can be highly successful in this population, particularly in nontraditional care settings. In a cluster-randomized trial that included 600 individuals with chronic HCV infection who were engaged in an opioid treatment program, provision of antiviral therapy through the program, directed by an HCV specialist over telemedicine, increased rates of antiviral initiation (92 versus 40 percent) and sustained virologic response (85 versus 30 percent) compared with traditional referral to a specialist clinic for treatment [9]. These data highlight the impact of reducing barriers to care for individuals with opioid use disorder and support our recommendation to treat all patients for chronic HCV, regardless of active drug use. (See "Patient evaluation and selection for antiviral therapy for chronic hepatitis C virus infection", section on 'Active drug use'.)

Glucocorticoid plus mycophenolate for autoimmune hepatitis (May 2024)

Mycophenolate, an antimetabolite, is under investigation for inducing remission in adults with autoimmune hepatitis (AIH). In a trial including 70 adults with AIH, prednisolone plus mycophenolate mofetil resulted in higher rates of biochemical remission at six months compared with prednisolone plus azathioprine (56 versus 29 percent) [10]. Rates of serious adverse events and drug discontinuation were lower in the mycophenolate group (0 versus 13 percent and 5 versus 26 percent, respectively). These data show promise, and we anticipate using combination therapy with a glucocorticoid plus mycophenolate as an option for patients with AIH who are at risk for side effects from high-dose glucocorticoid monotherapy. (See "Management of autoimmune hepatitis", section on 'Selecting initial therapy'.)

Resmetirom for metabolic dysfunction-associated steatohepatitis (MASH) (April 2024)

Therapeutic options for adults with metabolic dysfunction-associated steatohepatitis (MASH) are expanding. In a trial comparing two doses of resmetirom (a thyroid hormone receptor-beta agonist) with placebo in nearly 1000 adults with MASH and liver fibrosis stage F1B, F2, or F3, resmetirom resulted in higher rates of MASH resolution at 52 weeks (100 mg, 80 mg, placebo: 30, 26, and 10 percent, respectively) [11]. Resmetirom also increased the percentage of patients in whom fibrosis improved by at least one stage (100 mg, 80 mg, placebo: 26, 24, and 14 percent, respectively). However, the treatment groups had more diarrhea and nausea. We anticipate using resmetirom as an option for patients with MASH and F2 or F3 fibrosis who do not achieve sustained weight loss. (See "Management of metabolic dysfunction-associated steatotic liver disease (nonalcoholic fatty liver disease) in adults", section on 'Pharmacologic therapies'.)

New guidelines for protoporphyria (March 2024)

Erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP) are rare cutaneous porphyrias that cause severe, nonblistering photosensitivity and liver disease; their rarity makes evidence-based management challenging. Two new guidelines from the Rare Diseases Clinical Research Network are available to help guide diagnosis and management of EPP and XLP:

●Consensus guidelines discuss use of biochemical and genetic testing, use of afamelanotide, avoidance of ineffective therapies, methods of sun protection, and prevention of liver disease [12].

●Liver-specific guidelines discuss screening, prevention, and treatment of liver disease, including liver and hematopoietic stem cell transplantation for advanced disease [13].

●(See "Erythropoietic protoporphyria and X-linked protoporphyria", section on 'Management'.)

Elafibranor for treating primary biliary cholangitis (March 2024)

Elafibranor, a dual peroxisome proliferator-activated receptor (PPAR)-alpha and PPAR-delta agonist, is under investigation for treating primary biliary cholangitis (PBC). In a trial including 161 patients with PBC who had intolerance or inadequate response with ursodeoxycholic acid, elafibranor resulted in higher rates of biochemical response compared with placebo after 52 weeks (51 versus 4 percent) [14]. Elafibranor also resulted in higher rates of normalized alkaline phosphatase (15 versus 0 percent). Gastrointestinal side effects (eg, abdominal pain) occurred more frequently in the elafibranor group. Further studies and regulatory approval are needed to clarify the role of elafibranor in treating PBC. (See "Overview of the management of primary biliary cholangitis", section on 'Peroxisome proliferator-activated receptor [PPAR] agonists'.)

Seladelpar for treating primary biliary cholangitis (March 2024)

Seladelpar, a peroxisome proliferator-activated receptor-delta agonist, is under investigation for treating primary biliary cholangitis (PBC). In a trial including 193 patients with PBC who had intolerance or inadequate response with ursodeoxycholic acid, seladelpar resulted in higher rates of biochemical response compared with placebo after 12 months (62 versus 20 percent) [15]. In addition, seladelpar resulted in higher rates of normalized alkaline phosphatase (25 versus 0 percent). For patients with moderate to severe pruritus, seladelpar reduced symptom severity. These data show promise, but further studies and regulatory approval are needed before incorporating seladelpar into clinical practice. (See "Overview of the management of primary biliary cholangitis", section on 'Peroxisome proliferator-activated receptor [PPAR] agonists'.)

Pyogenic liver abscess and colorectal cancer (February 2024)

Studies from Asia suggest that pyogenic liver abscess is associated with increased incidence of colorectal cancer, but studies outside Asia are scarce. In a 10-year retrospective study from 120 hospitals in the United States, the incidence of colorectal cancer among over 8000 patients with liver abscess was almost fourfold higher during the first six months after diagnosis of liver abscess compared with 23,000 matched controls without liver abscess [16]. The correlation was not observed among patients whose liver abscess was due to cholangitis or cholecystitis, and the type of organism causing the abscess did not correlate with the incidence of cancer. These findings support prompt screening for colorectal cancer in patients with pyogenic liver abscess, particularly in patients without an underlying hepatobiliary cause. (See "Pyogenic liver abscess", section on 'Association with colorectal cancer'.)

Mortality risk in alcohol-associated liver disease (January 2024)

Few studies have reported the long-term outcomes of patients with alcohol-associated liver disease (ALD). In a national registry study including over 23,000 patients with ALD diagnosed at median age 58 years, 67 percent died during >100,000 person-years of follow-up and liver disease was the primary cause of death in 45 percent [17]. The 5- and 10-year mortality rates due to liver disease were 26 and 31 percent, respectively. These data emphasize the importance of treating patients with alcohol use disorder and may inform strategies to prevent liver-related mortality in those with ALD. (See "Management of alcohol-associated steatosis and alcohol-associated cirrhosis", section on 'Mortality'.)

SMALL BOWEL AND COLONIC DISEASE

New guidelines on management of pouchitis (March 2024)

Pouchitis is common in patients with ulcerative colitis who have undergone restorative proctocolectomy with ileal pouch-anal anastomosis. The American Gastroenterological Association (AGA) has published new guidelines to address management of pouchitis [18]. The guidelines endorse several strategies including antibiotic therapy for initial treatment and glucocorticoids or advanced immunosuppressive agents (eg, biologic therapy) for patients who do not respond to antibiotics. For patients who respond to antibiotics but relapse frequently, AGA suggests use of probiotics or long-term antibiotics to prevent recurrence. Our approach to managing pouchitis is generally consistent with these guidelines. (See "Management of acute and chronic pouchitis", section on 'Introduction'.)

De-escalating combination therapy in patients with inflammatory bowel disease (March 2024)

In patients with inflammatory bowel disease (IBD), the goal of de-escalating combination therapy (anti-tumor necrosis factor [TNF] agent plus an immunomodulator) is preventing relapse while minimizing adverse effects. However, the magnitude of risk for relapse is uncertain. In a meta-analysis of randomized trials of patients with sustained, glucocorticoid-free IBD remission on combination therapy (5 trials, 404 patients), relapse rates at one to two years were more than twofold higher following withdrawal of the anti-TNF agent compared with continuing combination therapy (32 versus 11 percent) [19]. Relapse rates did not increase following immunomodulator withdrawal. These data support our approach to de-escalating combination therapy by withdrawing the immunomodulator while continuing anti-TNF maintenance therapy. (See "Medical management of moderate to severe Crohn disease in adults", section on 'Remission achieved with anti-TNF-based regimen'.)

Mirikizumab for moderate to severe ulcerative colitis (August 2023, Modified January 2024)

Therapeutic options for adults with moderate to severe ulcerative colitis (UC) are expanding. In an induction trial comparing mirikizumab (a monoclonal antibody that targets the p19 subunit of interleukin-23) with placebo in nearly 1300 patients, mirikizumab (300 mg intravenously every four weeks) resulted in higher rates of clinical remission after 12 weeks (24 versus 13 percent) [20]. In the maintenance trial including over 500 patients, mirikizumab (200 mg subcutaneously every four weeks) resulted in higher rates of clinical remission after 40 weeks (50 versus 25 percent). Based on these data, the US Food and Drug Administration approved mirikizumab for moderate to severe UC [21]. We anticipate using mirikizumab as first- or second-line therapy for adults with moderate to severe UC. (See "Management of moderate to severe ulcerative colitis in adults", section on 'Anti-interleukin antibody-based therapy'.)