Can a covered biliary stent get blocked?

Yes, a covered biliary stent can become blocked (occluded), though it is less likely to get clogged compared to uncovered stents. However, blockage still remains a potential risk, and it can happen for various reasons:

Reasons for Blockage:

1. Bile Sludge or Stones:

• Bile, which is supposed to flow freely through the stent, can sometimes form sludge (a mixture of bile and other particles) or stones (from the gallbladder or bile ducts). These can accumulate at the ends of the stent, leading to blockage.

2. Tumor Growth:

• In cases of malignant obstruction (like cancer), while the covering prevents tumor tissue from growing into the stent, it doesn't prevent the tumor from growing around or compressing the stent, which can cause a narrowing or occlusion of the bile duct.

3. Biofilm Formation:

• Bacterial growth on the stent can form a slimy coating called a biofilm, which can reduce bile flow and contribute to blockage. This is more common in cases where the stent is left in place for an extended period.

4. Stent Migration:

• If the stent migrates out of place, the bile duct might get blocked either by the stent itself or by the accumulation of debris at the site where the stent used to be.

5. Stricture at the Stent’s End:

• A stricture (narrowing of the bile duct) can form at the area where the stent ends, either due to scarring or inflammation, which can eventually block bile flow through the stent.

Symptoms of a Blocked Covered Biliary Stent:

• Jaundice (yellowing of the skin or eyes)

• Abdominal pain, especially in the upper abdomen or right side

• Fever or chills, indicating possible infection (cholangitis)

• Nausea or vomiting

• Itchy skin (pruritus)

• Changes in bile drainage (if you have a drainage catheter)

What Happens When a Covered Stent Gets Blocked?:

If the stent becomes blocked, doctors will typically take the following steps:

• Endoscopic procedures (like ERCP) can be used to remove or replace the stent.

• If the blockage is caused by stones or sludge, the doctor might clear the bile ducts during the procedure.

• In cases of infection, treatment with antibiotics may be needed, and the stent may need to be replaced or flushed.

Preventing Blockage:

• Regular monitoring through imaging or other tests (such as ERCP or ultrasound) helps doctors keep an eye on the stent’s condition and catch blockages early.

• If there’s a concern about tumor growth, biofilm, or stones, doctors may replace or clean the stent to maintain proper bile flow.

Would you like more information on how doctors manage stent blockages or alternative treatments when stents fail?