Reply to Fuccio and Cennamo

We thank Drs Fuccio and Cennamo for their interest in the cannulation paper. I agree that the recent data suggests that wire-guided cannulation (WGC) should now be the initial and preferred technique for conventional biliary cannulation. Two published meta-analyses, including the study by Cennamo and co-workers of the five randomized trials, confirm superior primary cannulation rates, decreased precut requirements and a significantly reduced risk of post-ERCP pancreatitis (PEP) [1] [2]. Thus, it seems that not only in theory, but also in practice, WGC for biliary cannulation is both safer and more effective.

However I would caution that there are some limitations with the published literature which have not been examined in either of the meta-analyses. An established expert consensus on the definition of WGC is at present absent and technique may have been significantly different between the published trials. At least two of the randomized trials comprising a total of 700 patients and thus nearly half those in the published literature were single-operator studies [3] [4]. Some caution should be exercised in the interpretation of single-operator studies. Such studies, by their nature, are subject to bias which may potentially favor the preferred technique of the single operator. Multicenter randomized controlled studies are the gold standard and single-center studies with multiple operators are the second best. The other three studies involving multiple operators, including our own of 413 patients (where PEP was approximately 7 % in both groups) [5], confirmed superior primary cannulation in all and lower PEP in only one; however the incidence of PEP was high, at above 15 %, in the contrast arm in the latter multicenter study [6].

Clearly further study and understanding is required. Guide wire cannulation is certainly our preferred technique but, as the evidence suggests, it is not a complete panacea for the prevention of PEP.

Competing interests: None

References

• 1 Cennamo V, Fuccio L, Zagari R M. et al . Can a wire-guided cannulation technique increase bile duct cannulation rate and prevent post-ERCP pancreatitis?: A meta-analysis of randomized controlled trials.  Am J Gastroenterol. 2009;  104 2343-2350
• 2 Cheung J, Tsoi K K, Quan W-L. et al . Guidewire versus conventional contrast cannulation of the common bile duct for the prevention of post-ERCP pancreatitis: a systematic review and meta-analysis.  Gastrointest Endosc. 2009;  70 1211-1219
• 3 Lella F, Bagnolo F, Colombo E. et al . A simple way of avoiding post-ERCP pancreatitis.  Gastrointest Endosc. 2004;  59 830-834
• 4 Lee T H, Park D H, Park J Y. et al . Can wire-guided cannulation prevent post-ERCP pancreatitis? A prospective randomized trial.  Gastrointest Endosc. 2009;  69 444-449
• 5 Bailey A A, Bourke M J, Williams S J. et al . A prospective randomized trial of cannulation technique in ERCP: effects on technical success and post-ERCP pancreatitis.  Endoscopy. 2008;  40 296-301
• 6 Artifon E L, Sakai P, Cunha J E. et al . Guidewire cannulation reduces risk of post-ERCP pancreatitis and facilitates bile duct cannulation.  Am J Gastroenterol. 2007;  102 2154-2156