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Chandan, Saurabh

0000-0002-2661-6693

Mayo Clinic

Gastroenterology and Hepatology, CHI Health Creighton University Medical Center, Omaha, United States.

Citations 20

EUS-guided versus percutaneous liver biopsy: A comprehensive review and meta-analysis of outcomes

Endoscopic Ultrasound | October 4, 2022 | Volume: 12 | Issue: 2 | Pages: 171-180

10.4103/eus-d-21-00268 | PMID 36204798

ABSTRACT EUS-guided liver biopsy (EUS-LB) has gained momentum in recent years, especially with availability of newer needle designs. Given the emerging comparative data on EUS-LB with second-generation needles and percutaneous LB (PC-LB), we conducted a systematic review and meta-analysis to compare the safety and efficacy of the two techniques. We searched multiple databases from inception through November 2021 to identify studies comparing outcomes of EUS-LB and PC-LB. Pooled estimates were calculated using a random-effects model, and the results were expressed in terms of pooled proportions and odds ratio (OR) along with relevant 95% confidence intervals (CIs). Five studies with 748 patients were included in the final analysis. EUS-LB was performed in 276 patients and PC-LB in 472 patients. Across all studies, PC-LB had an overall higher diagnostic accuracy than EUS-LB, 98.6% confidence interval (CI: 94.7–99.7) versus 88.3% (49.6–98.3), OR: 1.65, P = 0.04. On assessing data from randomized controlled trials, there was no difference between the two. While pooled diagnostic adequacy and overall adverse events were not significantly different between PC-LB and EUS-LB, the former was superior in terms of the mean number of complete portal tracts (CPT) and total specimen length. PC-LB and EUS-LB produce similar results. PC-LB allows obtaining longer samples and more CPT. Further studies are needed to see if these trends hold up as more providers begin to perform EUS-LB.
Endoscopic Stenting in Crohn’s Disease-related Strictures: A Systematic Review and Meta-analysis of Outcomes

Inflammatory Bowel Diseases | July 26, 2022 | Volume: 29 | Issue: 7 | Pages: 1145-1152

10.1093/ibd/izac153 | PMID 35880681

Abstract Background Crohn’s disease (CD) is a chronic progressive condition that is complicated by intestinal or colonic stricture in nearly 30% of cases within 10 years of the initial diagnosis. Endoscopic balloon dilation (EBD) is associated with a risk of perforations and recurrence rates of up to 60% at 5 years. Endoscopic stenting has been used as an alternative to EBD, but data on its safety and efficacy are limited. We conducted a systematic review and meta-analysis to assess the outcomes of endoscopic stenting in CD-related strictures. Methods A systematic and detailed search was run in January 2022 with the assistance of a medical librarian for studies reporting on outcomes of endoscopic stenting in CD-related strictures. Meta-analysis was performed using random-effects model, and results were expressed in terms of pooled proportions along with relevant 95% confidence intervals (CIs). Results Nine studies with 163 patients were included in the final analysis. Self-expanding metal stents (SEMS) including both partial and fully covered were used in 7 studies, whereas biodegradable stents were used in 2 studies. Pooled rate of clinical success and technical success was 60.9% (95% CI, 51.6-69.5; I2 = 13%) and 93% (95% CI, 87.3-96.3; I2 = 0%), respectively. Repeat stenting was needed in 9.6% of patients (95% CI, 5.3-16.7; I2 = 0%), whereas pooled rate of spontaneous stent migration was 43.9% (95% CI, 11.4-82.7; I2 = 88%). Pooled incidence of overall adverse events, proximal stent migration, perforation, and abdominal pain were 15.7%, 6.4%, 2.7%, and 17.9%, respectively. Mean follow-up period ranged from 3 months to 69 months. Discussion Endoscopic stenting in CD-related strictures is a safe technique that can be performed with technical ease, albeit with a limited clinical success. Postprocedure abdominal pain and proximal stent migration are some of the common adverse events reported.
Safety and efficacy of liquid nitrogen spray cryotherapy in Barrett’s neoplasia – a comprehensive review and meta-analysis

Endoscopy International Open | July 21, 2022 | Volume: 10 | Issue: 11 | Pages: E1462-E1473

10.1055/a-1906-4967 | PMID 36397870

Abstract Background and study aims Barrett’s esophagus (BE) is a precursor condition to esophageal adenocarcinoma (EAC), resulting in transformation of the squamous epithelium of distal esophagus to columnar-lined epithelium with intestinal metaplasia (IM). Liquid nitrogen spray cryotherapy (LNSC) is a non-contact method of BE eradication and has been used both as primary and salvage therapy. We conducted a systematic review and meta-analysis to assess the safety and efficacy of LNSC. Methods We searched multiple databases from inception through December 2021 to identify studies on use of LNSC for Barrett’s neoplasia. Pooled estimates were calculated using random-effects model and results were expressed in terms of pooled proportions with relevant 95 % confidence intervals (CIs) of complete eradication (CE) of dysplasia(D), high grade dysplasia (HGD) and IM. Results Fourteen studies with 707 patients were included in our final analysis. Overall pooled rates of CE-D, CE-HGD and CE-IM were 80.8 % (CI 77.4–83.8; I2 62), 90.3 % (CI 85.2–93.7; I2 33) and 55.8 % (CI 51.7–59.8; I2 73) with follow up ranging from 4.25 months to 69.7 months. In patients with follow up beyond 24 months, the rates of CE-D and CE-IM were 83.6 % (CI 77.6–88.2; I2 60) and 54.7 % (CI 47.6–61.6; I2 81). Among LNSC naïve patients with prior history of endoscopic resection, the rates were 79.9 % (CI 73.3–85.2; I2 50) and 67.1 % (CI 59.5–73.8; I2 0). Pooled rate of therapeutic failures, defined as lack of response to LNSC therapy, was 23.6 % (CI 19.4–28.3; I2 73). Post LNSC strictures and perforation pooled rates were 4 % and 0.8 %, respectively, which are similar to those previously reported for RFA. Conclusions Our analysis suggests that liquid nitrogen spray cryotherapy is an acceptable treatment for BE in both ablation naïve and experienced patients.
Colonoscopy-Related Adverse Events in Patients With Abnormal Stool-Based Tests: A Systematic Review of Literature and Meta-analysis of Outcomes

American Journal of Gastroenterology | January 14, 2022 | Volume: 117 | Issue: 3 | Pages: 381-393

10.14309/ajg.0000000000001614 | PMID 35029161

INTRODUCTION: Colorectal cancer (CRC) screening programs based on the fecal immunochemical test (FIT) and guaiac-based fecal occult blood (gFOBT) are associated with a substantial reduction in CRC incidence and mortality. We conducted a systematic review and comprehensive meta-analysis to evaluate colonoscopy-related adverse events in individuals with a positive FIT or gFOBT. METHODS: A systematic and detailed search was run in January 2021, with the assistance of a medical librarian for studies reporting on colonoscopy-related adverse events as part of organized CRC screening programs. Meta-analysis was performed using the random-effects model, and the results were expressed for pooled proportions along with relevant 95% confidence intervals (CIs). RESULTS: A total of 771,730 colonoscopies were performed in patients undergoing CRC screening using either gFOBT or FIT across 31 studies. The overall pooled incidence of severe adverse events in the entire patient cohort was 0.42% (CI 0.20–0.64); I 2 = 38.76%. In patients with abnormal gFOBT, the incidence was 0.2% (CI 0.1–0.3); I 2 = 24.6%, and in patients with a positive FIT, it was 0.4% (CI 0.2–0.7); I 2 = 48.89%. The overall pooled incidence of perforation, bleeding, and death was 0.13% (CI 0.09–0.21); I 2 = 22.84%, 0.3% (CI 0.2–0.4); I 2 = 35.58%, and 0.01% (CI 0.00–0.01); I 2 = 33.21%, respectively. DISCUSSION: Our analysis shows that in colonoscopies performed after abnormal stool-based testing, the overall risk of severe adverse events, perforation, bleeding, and death is minimal.
Safety and Efficacy of Biological Therapy in Chronic Antibiotic Refractory Pouchitis

Journal of Clinical Gastroenterology | May 29, 2021 | Volume: 55 | Issue: 6 | Pages: 481-491

10.1097/mcg.0000000000001550 | PMID 34049383

Background: Pouchitis is the most common long-term complication after ileal pouch-anal anastomosis in patients with ulcerative colitis. Those with ≥3 episodes of pouchitis/year and symptoms despite antibiotics are considered to have chronic antibiotic refractory pouchitis (CARP). While several agents including probiotics, steroids and immunomodulators have been used, treatment of CARP remains challenging. We conducted a systematic review and meta-analysis evaluating the safety and efficacy of various biological agents in treatment of CARP. Methods: Multiple databases were searched through June 2020 for studies that reported the efficacy and safety of biological therapy including antitumor necrosis factor-alpha agents [infliximab (IFX) and adalimumab (ADA)], vedolizumab (VDZ), and ustekinumab in CARP. We excluded studies on Crohn’s like and/or other inflammatory complications of the pouch. Meta-analysis was performed to calculate pooled rates of clinical as well as endoscopic improvement and remission. Results: We included 15 studies with 311 patients in our final analysis. Ninety-two patients were treated with IFX, 42 with ADA, 144 with VDZ and 33 with ustekinumab. Pooled rate of clinical improvement was 71.4%, 58.2%, 47.9% and clinical remission was 65.7%, 31%, 47.4% with IFX, ADA, and VDZ, respectively. Pooled rate of endoscopic improvement was achieved in 61.2% patients treated with VDZ while endoscopic remission was achieved in 70.3% patients treated with IFX. Adverse events were reported in 3.9% patients. Conclusion: Biologic therapy is safe and effective in the treatment of CARP.
Intracystic Glucose Levels in Differentiating Mucinous From Nonmucinous Pancreatic Cysts

Journal of Clinical Gastroenterology | March 18, 2021 | Volume: 56 | Issue: 2 | Pages: e131-e136

10.1097/mcg.0000000000001507 | PMID 33731599

Background: Mucinous pancreatic cysts are well reported to transform into pancreatic adenocarcinoma, whereas nonmucinous cysts are mostly benign with low risk for malignant transformation. Nonsurgical methods of differentiating mucinous and nonmucinous pancreatic cysts are challenging and entail a multi investigational approach. Low intracystic glucose levels have been evaluated in multiple studies for its accuracy in differentiating mucinous from nonmucinous cysts of the pancreas. Methods: Multiple databases were searched and studies that reported on the utility of intracystic glucose levels in diagnosing mucinous pancreatic cysts were analyzed. Meta-analysis was conducted using the random-effects model, heterogeneity was assessed by I 2%, and pooled diagnostic test accuracy values were calculated. Results: Seven studies were included in the analysis from an initial total of 375 citations. The pooled sensitivity of low glucose in differentiating mucinous pancreatic cyst was 90.5% [95% confidence interval (CI): 88.1-92.5; I 2=0%] and the pooled specificity was 88% (95% CI: 80.8-92.7; I 2=79%). The sensitivity at a glucose cut-off of 50 was 90.1% (95% CI: 87.2-92.5; I 2=0%) and the specificity was 85.3% (95% CI: 76.8-91.1; I 2=76%). The sensitivity of glucose levels in pancreatic cyst fluid taken by endoscopic ultrasound guided fine-needle aspiration was 90.8% (95% CI: 87.9-93.1; I 2=0%) and the specificity was 90.5% (95% CI: 81.7-95.3; I 2=83%). The sensitivity of point-of-care glucometers was 89.5% (95% CI: 87.9-93.1; I 2=0%) and specificity was 83.9% (95% CI: 68.5-92.6; I 2=43%). Conclusions: Low glucose level at a cut-off of 50 mg/dL on fluid samples collected by endoscopic ultrasound guided fine-needle aspiration and analyzed by point-of-care glucometer achieves excellent diagnostic accuracy in differentiating mucinous pancreatic cysts.
Photodynamic Therapy (PDT), Radiofrequency Ablation (RFA) With Biliary Stents in Palliative Treatment of Unresectable Extrahepatic Cholangiocarcinoma

Journal of Clinical Gastroenterology | March 18, 2021 | Volume: 56 | Issue: 2 | Pages: e153-e160

10.1097/mcg.0000000000001524 | PMID 33780214

Background and Aim: Extrahepatic unresectable cholangiocarcinoma carries a dismal prognosis. In addition to biliary drainage by stent placement; photodynamic therapy (PDT) and radiofrequency ablation (RFA) have been tried to prolong survival. In this meta-analysis, we appraise the current known data on the use of PDT, RFA in the palliative treatment of extrahepatic unresectable cholangiocarcinoma. Methods: We searched multiple databases from inception through July 2020 to identify studies that reported on PDT and RFA. Pooled rates of survival, stent patency, 30-, 90-day mortality, and adverse events were calculated. Study heterogeneity was assessed using I 2% and 95% prediction interval. Results: A total of 55 studies (2146 patients) were included. A total of 1149 patients underwent treatment with PDT (33 studies), 545 with RFA (22 studies), and 452 patients with stent-only strategy. The pooled survival rate with PDT, RFA, and stent-only groups was 11.9 [95% confidence interval (CI): 10.7-13.1] months, 8.1 (95% CI: 6.4-9.9) months, and 6.7 (95% CI: 4.9-8.4) months, respectively. The pooled time of stent patency with PDT, RFA, and stent-only groups was 6.1 (95% CI: 4.2-8) months, 5.5 (95% CI: 4.2-6.7) months, and 4.7 (95% CI: 2.6-6.7) months, respectively. The pooled rate of 30-day mortality with PDT was 3.3% (95% CI: 1.6%-6.7%), with RFA was 7% (95% CI: 4.1%-11.7%) and with stent-only was 4.9% (95% CI: 1.7%-13.1%). The pooled rate of 90-day mortality with PDT was 10.4% (95% CI: 5.4%-19.2%) and with RFA was 16.3% (95% CI: 8.7%-28.6%). Conclusion: PDT seemed to demonstrate better overall survival and 30-day mortality rates than RFA and/or stent-only palliation.
Hepatitis-B Vaccine Response in Inflammatory Bowel Disease Patients: A Systematic Review and Meta-analysis

Inflammatory Bowel Diseases | January 4, 2021 | Volume: 27 | Issue: 10 | Pages: 1610-1619

10.1093/ibd/izaa353 | PMID 33393585

Abstract Background Data on efficacy of hepatitis-B vaccine (HBV) in patients with inflammatory bowel disease (IBD) is limited. Our aim was to review the literature and perform meta-analysis of available studies to quantify efficacy of HBV in patients with IBD. Methods We conducted a comprehensive search of several databases (inception to July 2020) to identify studies evaluating efficacy of HBV in patients with IBD. Random effects model was used to calculate the pooled rates and I2 percentage values were used to assess the heterogeneity. Results A total of 14 studies (2375 patients) were included. Four data sets were available from 2 studies that compared HBV response in patients with IBD against healthy controls. The pooled odds ratio of HBV response in IBD patients was 0.13 (95% CI, 0.05–0.33, P = 0.001). The pooled proportion of adequate immune response (AIR) was 64% (95% CI, 55–72.1, P = 0.003) from 13 data sets, and effective immune response (EIR) was 39.7% (95% CI, 30.7–49.5, P = 0.04) from 10 data sets. Conclusion Patients with IBD on immunosuppression demonstrated significantly reduced HBV response as compared with general population.
Multimedia based education on bowel preparation improves adenoma detection rate: Systematic review & meta‐analysis of randomized controlled trials

Digestive Endoscopy | August 14, 2020 | Volume: 33 | Issue: 5 | Pages: 730-740

10.1111/den.13809 | PMID 32794240

Background and AimsColorectal cancer (CRC) is the third most common cause of cancer worldwide. Studies have shown a strong association between screening colonoscopy and a reduced risk of death from colorectal cancers. The incidence of poor bowel preparation has been reported in up to 25% cases. We conducted a systematic review and comprehensive meta‐analysis to evaluate the effect of patient education using multimedia platforms on adenoma detection rate and adequacy of bowel preparation.MethodsMultiple databases were searched through May 2020 for studies that reported the efficacy of multimedia education (smartphone app and online audio‐visual aids) in improving quality of bowel preparation and its effect on adenoma detection rate (ADR). Meta‐analysis was performed to determine whether multimedia based patient education (MM) helps improve ADR and bowel preparation quality as compared to controls (CT).ResultsWe included 13 randomized controlled trials with a total of 3754 patients. Eight studies reported outcomes on ADR and 12 reported on adequacy of bowel preparation. Overall ADR was higher in patients receiving multimedia based education as compared to CT (risk ratio (RR) 1.25, confidence interval (CI) 1.01–1.56, P = 0.04). A higher proportion of patients receiving multimedia based education achieved adequate bowel preparation (RR 1.2, CI 1.1–1.3, P = 0.001). In patients with mean age over 50 years, ADR was better in MM cohort as compared to controls (RR 1.3, CI 1.1–1.6, P = 0.001).ConclusionPre‐colonoscopy patient education using multimedia based platforms seems to improve ADR and the adequacy of bowel preparation.
Efficacy and safety of endoscopic ultrasound-guided therapy versus direct endoscopic glue injection therapy for gastric varices: systematic review and meta-analysis

Endoscopy | February 6, 2020 | Volume: 52 | Issue: 04 | Pages: 259-267

10.1055/a-1098-1817 | PMID 32028533

Abstract Background Gastric variceal bleeding carries significant mortality in the setting of portal hypertension. Among the endoscopic treatment options, endoscopic ultrasound (EUS)-guided glue and/or coil injection is a novel approach, but its role in the treatment of gastric varices is not established due to a lack of robust data. Methods We conducted a comprehensive search of several databases (inception to June 2019) to identify studies evaluating EUS in the treatment of gastric varices. Our primary goals were to estimate the pooled rates of treatment efficacy, obliteration and recurrence of gastric varices, early and late rebleeding, and adverse events with EUS-guided therapy in gastric varices. We also searched for studies that evaluated direct endoscopic glue (END-glue) injection for treatment of gastric varices, and used the pooled rates as comparators. Results 23 studies (851 patients) evaluating EUS-guided therapy were included. The pooled treatment efficacy was 93.7 % (95 % confidence interval [CI] 89.5 – 96.3, I 2 = 53.7), gastric varices obliteration was 84.4 % (95 %CI 74.8 – 90.9, I 2 = 77), gastric varices recurrence was 9.1 % (95 %CI 5.2 – 15.7, I 2 = 32), early rebleeding was 7.0 % (95 %CI 4.6 – 10.7, I 2 = 0), and late rebleeding was 11.6 % (95 %CI 8.8 – 15.1, I 2 = 22). The rates were comparable to END-glue therapy (28 studies, 3467 patients) except for obliteration, which was significantly better with EUS-guided therapy. On subgroup analysis, EUS-coil/glue combination showed superior outcomes. Conclusions EUS-guided therapy demonstrated clinical efficacy for treatment of gastric varices in terms of obliteration, recurrence, and long-term rebleeding, and may be superior to END-glue.