Benign Biliary Strictures & Fistula

Summary: Internal Biliary Fistulae

• Etiology:
  • Calculous biliary tract disease: Accounts for 90% of all internal biliary fistulae.
  • Peptic ulcer disease: Accounts for 6%.
  • Neoplasm, trauma, parasitic infection, and congenital anomalies: Make up the remaining 4%.
• Types of Biliary Fistulae:
  • Cholecystoenteric fistulae: Constitute 70% to 85% of all biliary fistulae.
    • Cholecystoduodenal: 55% to 75% of cholecystoenteric fistulae.
    • Cholecystocolic: 15% to 30%.
    • Cholecystogastric: 2% to 5%.
• Choledochoduodenal Fistulae:
  • Proximal Choledochoduodenal Fistula:
    • Most common abnormal communication between the CBD and adjacent structures (often the duodenum).
    • Represents 4% to 20% of all biliary-enteric fistulae.
    • Historically, mainly caused by peptic ulcer erosion; now less common due to effective peptic ulcer treatment.
    • Other causes: Cholelithiasis, operative trauma, duodenal diverticula, echinococcal infection, Crohn’s disease, and neoplasms (stomach, distal bile duct, ampullary region, duodenum).
  • Distal Choledochoduodenal Fistula:
    • Connects to the duodenum in the distal 2 cm of the CBD.
    • Can be visualized during PTC and ERCP.
    • The incidence is variable but may be underreported; a large series from Argentina reported an incidence of 0.7%.

Cholecystoduodenal Fistulae

• Symptomatic Nature:
  • Most cholecystoduodenal fistulae are asymptomatic or present with common digestive complaints consistent with gastric or biliary tract disease.
  • They do not typically result in gallstone ileus.
• Elective Surgery Considerations:
  • Elective surgery may not be necessary for completely asymptomatic individuals.
  • In elderly, minimally symptomatic patients, surgery may have an unfavorable risk-to-benefit ratio.
• Incidental Findings:
  • These fistulae are often found during an upper GI barium study or abdominal surgery for unrelated issues.
• Treatment Approach:
  • In healthy patients, the best long-term outcome may be achieved with cholecystectomy, closure of the fistula, and treatment of any common duct pathology.

This summary provides insights into the typical presentation and management considerations for cholecystoduodenal fistulae, emphasizing the importance of patient-specific factors in determining the need for surgical intervention.

(Source: Blumgart 6th edition, page 682)

Parapapillary Fistula Classification

• Study Context: In a study involving 1500 ERCP patients, Ikeda et al. classified parapapillary fistulae into two types based on their characteristics and etiology.
• Type I Fistula:
  • Location: Small fistula opening on the longitudinal fold of the duodenum, just proximal to the papilla.
  • Cause: Likely caused by the penetration of a small calculus through the intramural portion of the common duct into the duodenum.
• Type II Fistula:
  • Location: Larger opening in the duodenum wall, adjacent to the longitudinal fold.
  • Cause: Likely caused by a relatively large stone eroding from the extramural portion of a greatly dilated common duct into the duodenum

Thoracobiliary and Bronchobiliary Fistulae

• Definition:
  • Thoracobiliary and Bronchobiliary Fistulae: These refer to abnormal communications between the biliary tree and either the pleural cavity or bronchial tree.
• Categories of Bronchobiliary Fistula:
  1. Infection:
     • Parasitic diseases, such as echinococcal or amebic infection, are the principal causes worldwide.
  2. Trauma:
     • Iatrogenic injuries to the biliary system are the most common cause in developed countries.
  3. Congenital Causes:
     • Congenital abnormalities can also lead to bronchobiliary fistulae.
• Diagnostic Imaging:
  • Cholescintigraphy: Effective in demonstrating bronchobiliary fistulae.
  • CT and MRCP: Useful in assessing the upper abdomen but rarely visualize the fistula tract.
• Emerging Causes:
  • Liver Tumor Ablative Therapies: Newer treatments like radiofrequency ablation have been reported to cause bronchobiliary fistulae.

This summary highlights the causes, diagnosis, and emerging trends related to thoracobiliary and bronchobiliary fistulae, with a focus on the importance of recognizing iatrogenic and infectious origins.

(Source: Blumgart 6th edition, page 677)

Effects of Long-Term Total External Biliary Fistula

• Fluid and Electrolyte Disturbances:
  • Sodium loss typically exceeds chloride loss, leading to metabolic acidosis.
  • Initially, serum potassium levels are lowered, but fluid loss can cause decreased plasma volume, potentially leading to low-output renal failure and hyperkalemia.
• Nutrient Absorption Issues:
  • Absence of bile in the GI tract interferes with the absorption of fat-soluble vitamins.
  • Vitamin K deficiency is commonly seen early and can be diagnosed by a prolonged prothrombin time.
  • Vitamin A and D deficiencies may occur with long-term biliary fistula but are rarely seen today.
• Disruption of Intestinal Barrier Function:
  • Total biliary loss can lead to disruption of intestinal barrier function and bacterial translocation, contributing to further complications.

(Source: Blumgart 6th edition, page 687)

Biliary Stricture Due to Chronic Calcific Pancreatitis

Question:

Answer:

d) Occurs exclusively in alcohol-related CCP

Comment:

The correct answer is d) Occurs exclusively in alcohol-related CCP because this statement is false.

Here's an explanation for each option:

• a) Present in 30% of CCP: This is true. Biliary strictures occur in a significant proportion of patients with Chronic Calcific Pancreatitis (CCP), approximately 30%. These strictures are often due to the fibrotic changes and calcifications associated with CCP, which can compress or obstruct the bile duct.
• b) Pain is similar to biliary colic: This is true. The pain associated with biliary strictures in CCP can be similar to that of biliary colic. It typically presents as severe, episodic pain in the upper abdomen, often radiating to the back, which is characteristic of biliary colic.
• c) Cholangitis and fever are less common: This is true. Although biliary strictures can lead to cholestasis, the occurrence of acute cholangitis (with fever, jaundice, and abdominal pain) is less common in CCP-related strictures compared to other causes of biliary obstruction, such as choledocholithiasis.
• d) Occurs exclusively in alcohol-related CCP: This is false. Biliary strictures in CCP can occur in various forms of chronic pancreatitis, not just those related to alcohol. While alcohol-related chronic pancreatitis is a common cause, strictures can also develop in other forms of CCP, including those caused by genetic factors, autoimmune pancreatitis, and idiopathic cases.

IgG4 Systemic Disease and Sclerosing Cholangitis

Overview:

• Prevalence: IgG4 sclerosing cholangitis is a rare biliary manifestation of IgG4 systemic disease, with an estimated prevalence of 1.8 per 100,000 individuals and an incidence of 0.5 per 100,000.
• Male Predominance: There is a strong male predominance in this condition.
• Histological Features: The disease is characterized by lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis. These morphological features can mimic hilar cholangiocarcinoma (CCA) and primary sclerosing cholangitis (PSC).
• Association with Autoimmune Pancreatitis: IgG4 sclerosing cholangitis is often associated with type I autoimmune pancreatitis, and patients may also have other extrapancreatobiliary manifestations like sialadenitis, renal infiltrates, interstitial lung disease, ocular disturbances, and hypopituitarism.

Diagnosis:

• Serum IgG4 Levels: An elevated serum IgG4 level (>135 mg/dL) aids in diagnosis, but 10% to 40% of patients may have normal levels.
• Biliary Tract Imaging: Complete biliary imaging is necessary, with stricture patterns offering diagnostic clues.
• Biliary Tract Biopsy: While useful, biopsy may not entirely rule out CCA due to the potential for malignancy to induce reactive changes mimicking IgG4 sclerosing cholangitis.

Treatment:

• Steroids: The mainstay of treatment is steroids, which often lead to dramatic improvements, sometimes eliminating the need for procedural or surgical intervention. A short course of steroids followed by imaging to confirm resolution can help confirm the diagnosis.
• In severe cases Rituximab can be used

Differentiation from Malignancy:

• Differentiation from biliary tract malignancy requires a combination of serum IgG4 levels, evaluation for other systemic manifestations, cholangiogram findings, bile duct cytology and biopsy review, and careful clinical monitoring.

Type 3 and 4 has high risk for CCA.

Question:

Answer:

b) Biopsy helps in ruling out CCA

Comment:

The correct answer is b) Biopsy helps in ruling out CCA because this statement is false.

Here's a breakdown of each option:

• a) Male preponderance: This is true. IgG4-related sclerosing cholangitis (IgG4-SC) shows a male predominance, similar to other conditions within the IgG4-related disease spectrum.
• b) Biopsy helps in ruling out CCA: This is false. While biopsy is important in the diagnosis of IgG4-SC, it does not definitively rule out cholangiocarcinoma (CCA). The histopathological findings in IgG4-SC can be similar to those seen in CCA, and in some cases, CCA may coexist with IgG4-SC. Therefore, a biopsy alone is not always sufficient to rule out malignancy, and additional diagnostic modalities are often required.
• c) Mimics CCA/PSC: This is true. IgG4-SC often mimics cholangiocarcinoma (CCA) and primary sclerosing cholangitis (PSC) both clinically and radiologically, which can complicate the diagnostic process. The similarities in imaging and presentation can lead to challenges in distinguishing these conditions.
• d) Associated with other organ involvement: This is true. IgG4-SC is often associated with other manifestations of IgG4-related disease, including involvement of organs such as the pancreas (autoimmune pancreatitis), retroperitoneum (retroperitoneal fibrosis), kidneys, salivary glands, and others.

MCQ: Comparison of PSC and IgG4-Related Cholangitis

Correct Answer: c) IgG4 elevation seen in 15%

Explanation:

• IgG4 elevation is seen in about 10-15% of cases of PSC. However, this feature is a hallmark of IgG4-related cholangitis, where IgG4 levels are typically elevated in the majority of patients. Therefore, while IgG4 elevation can occur in PSC, it is much more prominent in IgG4-related cholangitis.
• Male predominance and an age range of 50-60 years are more typical of IgG4-related cholangitis.
• The MRCP findings of short strictures with a mix of dilated and normal-sized ducts are characteristic of IgG4-related cholangitis rather than PSC.

Ampullary Stenosis Associated with Roux-en-Y Gastric Bypass

Overview:

• Association: Benign distal common bile duct stricture at the ampulla has been reported in patients post-Roux-en-Y gastric bypass (RYGB) for morbid obesity.
• Demographics: Affected patients are predominantly female with a mean age of 54 years, and symptoms can range from abdominal pain to severe cholangitis.
• Time to Diagnosis: Ampullary stenosis typically presents a mean of 7.5 years post-RYGB.
• Imaging: Diagnosis is aided by biliary imaging techniques such as MRCP or PTC.

Treatment:

• Initial Approach: The current treatment approach has shifted from open ampullectomy or biliary bypass to less invasive techniques like laparoscopic transgastric ERCP with sphincterotomy.
• Surgical Intervention: More invasive surgical options are considered if sphincterotomy fails, restenosis occurs, or if malignancy is strongly suspected.

Pathophysiology:

• The exact mechanism is unclear, but possible contributing factors include autoimmune conditions, chronic opioid use, and gastrointestinal regulatory hormonal changes post-RYGB.

Conclusion:

• While ampullary stenosis post-RYGB appears to be benign, malignancy must still be ruled out during patient evaluation.

Question:

Answer: The correct answer is a) Female preponderance

Comment:

Ampullary stenosis following Roux-en-Y gastric bypass (RYGB) indeed shows a female preponderance. The condition typically presents much later than 2.5 years post-surgery, often around 7.5 years on average. While endoscopic intervention is often used, initially, conservative management is preferred. Distinguishing ampullary stenosis from malignancy is crucial due to the overlapping symptoms, but the main distinguishing feature in the context of post-RYGB complications is the strong female preponderance in cases reported.

AIDS-related cholangiopathy

Answer: b) Caused by microsporidia, cryptosporidia, CMV

Explanation:

• Option a: AIDS-related cholangiopathy typically occurs when CD4 counts are less than 100 cells/HPF, not within the range of 100-300 cells/HPF.
• Option b: The correct answer is b. AIDS-related cholangiopathy is indeed caused by microsporidia, cryptosporidia, and CMV among other opportunistic infections.
• Option c: Management typically involves hydration, antibiotics, and HAART. Urgent ERCP is not mandatory and is usually reserved for specific complications.
• Option d: AIDS-related cholangiopathy can be associated with cholangiocarcinoma (CCA), although the incidence has decreased with the widespread use of HAART.

Investigation and Interpretation:

Investigation:

• ERCP (Endoscopic Retrograde Cholangiopancreatography)

Interpretation:

• Left Duct Dilated with Filling Defect: Indicates obstruction within the left biliary duct.
• Intrahepatic Stones with Left Duct Stricture: Suggests the presence of stones within the intrahepatic bile ducts leading to strictures.
• Compatible with Recurrent Pyogenic Cholangitis (RPC): The findings are indicative of RPC, a condition often seen in Southeast Asia, associated with intrahepatic stones and strictures, and recurrent episodes of cholangitis.

Recurrent Pyogenic Cholangitis (RPC):

1. Overview:

• First Described: 1930.
• Geographic Prevalence: Most common in Southeast Asian populations.
• Characterization:
  • Recurrent Episodes of Bacterial Cholangitis: Frequent bacterial infections of the bile ducts.
  • Bile Duct Strictures: Narrowing of bile ducts due to chronic inflammation.
  • Segmental Biliary Dilation: Widening of bile ducts with bile stasis.
  • Obstructive Jaundice and Ascending Cholangitis: Blockage of bile flow leading to jaundice and inflammation spreading from the bile ducts to the liver.
  • Pigmented Biliary Calculi: Formation of pigmented stones in the bile ducts.
  • Biliary Cirrhosis: Scarring of the liver caused by chronic bile duct disease.

2. Treatment Goals:

• Infection Eradication: Use of antimicrobials to treat bacterial infections.
• Elimination of Biliary Stones and Strictures: Requires multiple treatment sessions.

3. Surgical Management:

• Choledochojejunostomy or Hepaticojejunostomy with Biliary Access Procedure:
  • Purpose: Allows easy access to the biliary tree for clearing recurrent stones and dilating recurrent intrahepatic strictures.
  • Technique:
    • After standard cholecystectomy, a portion of the common bile duct (CBD) is isolated for choledochoenteric anastomosis.
    • A 60- to 70-cm segment of bowel is used for the Roux-en-Y limb.
    • Side-to-side choledochojejunostomy is constructed 10 to 15 cm from the end of the jejunal limb.
    • The blind limb of the jejunal access loop is brought through the abdominal wall for easy access.
    • No attempt is made at complete clearance of the CBD or hepatic radicles during the initial surgery.
  • Postoperative Care:
    • A stoma is created and matured in a "turn-back" fashion.
    • The stoma allows subsequent outpatient treatment of residual stones and strictures.
    • After radiologic treatment is completed, the stoma can be closed and buried in the subcutaneous tissues for future access.

4. Advantages of Surgical Approach:

• Less Radical than Hepatic Resection:
  • Lower morbidity and mortality.
  • Spares hepatic parenchyma, allowing potential recovery after biliary decompression.
• Effective Biliary Drainage:
  • Provides immediate relief of biliary sepsis.
  • Facilitates easy clearance of residual stones and dilation of strictures.
  • Minimizes the need for high-risk reoperative biliary procedures.
• Outpatient Management: Simplifies treatment of recurrent stones or strictures through access to the cutaneous jejunal limb.

Answer: c) Bilateral or intrahepatic- 40%

Explanation:

• Left duct = 40%
• Right Duct = 20%

Answer: c) Resection of involved segment

Answer: d) CBD exploration and primary closure

The management of RPC typically involves more extensive surgical interventions rather than primary closure due to the high incidence of recurrent stricture and stone formation.