EUS-guided prophylactic drainage of the gallbladder: a bridge too far.

We read with interest the study by Robles-Medranda et al1Robles-Medranda C. Oleas R. Puga-Tejada M. et al.Prophylactic EUS-guided gallbladder drainage prevents acute cholecystitis in patients with malignant biliary obstruction and cystic duct orifice involvement: a randomized trial (with video).Gastrointest Endosc. 2023; 97: 445-453Google Scholar regarding the utility of EUS-guided prophylactic drainage in patients with malignant bile duct obstruction undergoing palliative metal stenting. Although EUS-guided gallbladder drainage is a good option for nonsurgical candidates with acute cholecystitis, proposing routine prophylactic drainage in malignant bile duct obstruction seems like a bridge too far. We believe some issues require further clarification.1.What is the explanation for the inordinately high number of acute cholecystitis cases in this series compared with those in existing reports on ERCP-related adverse events?2Cao J. Peng C. Ding X. et al.Risk factors for post-ERCP cholecystitis: a single-center retrospective study.BMC Gastroenterol. 2018; 22: 128Google Scholar,3Jung J.H. Park S.W. Hyun B. et al.Identification of risk factors for obstructive cholecystitis following placement of biliary stent in unresectable malignant biliary obstruction: a 5-year retrospective analysis in single center.Surg Endosc. 2021; 35: 2679-2689Google Scholar2.Why did the authors choose to define the main outcome measure, called “definitive cholecystitis,” in accordance with the Tokyo criteria for “suspected cholecystitis,” where only 2 out of 3 diagnostic criteria are required? According to the authors, a patient presenting with right upper quadrant pain and systemic inflammation would meet the criteria for their main study outcome, when, in fact, cholangitis might be just as likely a diagnosis, according to the Tokyo criteria.4Yokoe M. Hata J. Takada T. et al.Tokyo guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis (with videos).J Hepatobiliary Pancreat Sci. 2018; 25: 41-54Google Scholar3.Did the authors consider the possibility that the intervention in the control group (ie, cholangioscopy and/or forceful [over]injection of contrast medium to identify the cystic duct) might constitute a significant risk factor for post-ERCP cholecystitis, similar to mechanisms identified in post-ERCP pancreatitis,5Zhang D. Man X. Li L. et al.Radiocontrast agent and intraductal pressure promote the progression of post-ERCP pancreatitis by regulating inflammatory response, cellular apoptosis, and tight junction integrity.Pancreatology. 2022; 22: 74-82Google Scholar thus introducing a significant bias in the analysis?4.In everyday practice it seems unlikely that the gallbladder will always be sufficiently distended to allow EUS-guided drainage, as was the case for all patients in the study’s active arm. A sufficiently distended gallbladder, favorable for EUS-guided drainage, is more likely to be associated with a patent cystic duct implanted above the site of the malignant stricture. Although prophylactic gallbladder drainage might be a reasonable option in a highly selected population, we believe that routine EUS-guided drainage should not be encouraged until additional data are available. All authors disclosed no financial relationships.