GI Endoscopy · 6 min read
Sump Syndrome: Open the Bottom of the Distal CBD After Side-to-Side CDD
The anastomosis drains. The native distal duct becomes a recess. Cholangitis years later is debris in that recess, not a new stone disease of youth.
Side-to-side choledochoduodenostomy was a pre-ERCP solution for a dilated duct full of stones. Bile then prefers the anastomosis. The native distal CBD becomes a sump. Food, pigment stone, and bacteria collect there and present as cholangitis, sometimes a decade later. Treatment is ERCP sphincterotomy plus clearance of the sump, not another bypass as the first move.
Experienced teaching points
Clinical Pearls
- Pneumobilia after CDD means the anastomosis is open. It does not mean the distal sump is clean.
- Look at the native papilla. That is the bottom of the pouch. Sphincterotomy plus balloon or basket is the drainage operation.
- Food debris is more common than stone in the Caroli-Bosc series. Sweep anyway.
- Recurrence is restenosis of the sphincterotomy years later. Extend it. Do not jump to revisional surgery first.
- This is not a new CBD stone in intact anatomy. Stone extraction technique: ERCP stones. Whether to do ERCP at all: ERCP vs EUS.
Clinical Bottom Line
| Question | Practical answer |
|---|---|
| What is the sump? | The native distal CBD between a side-to-side choledochoduodenostomy and the papilla. Bile prefers the anastomosis. The recess fills with food, sludge, and pigment stone. |
| When it shows up | Often years later. Caroli-Bosc (PMID 10650261): median 5-6 years, range to 28 years. Pain plus fever is common. Hepatic abscess and pancreatitis happen. |
| Treatment | ERCP at the native papilla: sphincterotomy, then balloon or basket clearance of the sump. That converts a blind pouch into a draining conduit. |
| Recurrence | Caroli-Bosc saw none at median 36 months. An AJG 1999 series (PMID 10201467) saw 19% late recurrence from restenosed sphincterotomy, retreated with a new cut. |
| What this is not | Not a reason to start with diagnostic ERCP in intact anatomy. Not the stone-extraction atlas. Not EUS-FNA. |
Why does a working anastomosis still cause cholangitis?
The side-to-side hole is usually large. Duodenal contents can reflux into the duct as easily as bile can leave. Gravity and loss of sphincter washout fill the distal recess. Brown pigment stone forms in infected static bile. You do not need a new gallbladder. Many of these patients already lost it.
Modern choledocholithiasis is an ERCP problem, so new CDDs are uncommon. The patients you will meet had open biliary surgery decades ago. Ask. Look for pneumobilia on CT. Then plan ERCP, not another anastomosis as first-line.
What did the endoscopic series actually show?
Caroli-Bosc 2000 (PMID 10650261): 30 patients. Food debris in 18, calculi in 10, both in 2. Sphincterotomy in all, no recorded complication, no recurrence over a median 36 months. That is why EST is the default.
PMID 10201467 is the caution: 31 patients, immediate improvement, then 6 of 31 (19%) returned at a median 58.5 months because the cut had restenosed. A second papillotomy worked. Hold both numbers. Do not promise a lifetime cure from one sphincterotomy, and do not send an elderly patient to revisional hepaticojejunostomy before you have extended the cut.
Cannulation risk and PEP prevention live on the PEP page. Access tricks live on biliary access.
Selected references
- Caroli-Bosc FX, et al. Endoscopic management of sump syndrome after choledochoduodenostomy: retrospective analysis of 30 cases. Gastrointest Endosc. 2000;51:180-183.
- Sump syndrome: endoscopic treatment and late recurrence. Am J Gastroenterol. 1999;94:972-975.
Last reviewed September 20, 2026. Written for clinicians facing cholangitis in someone with an old biliary bypass who still has a native papilla.
For your teaching file
Save this article as a PDF
Drop your email and we'll open a print-ready version you can save as a PDF — and you'll start getting our weekly GI endoscopy newsletter.