What is the incidence of biliary ascariasis?

Incidence of Biliary Ascariasis

The incidence of biliary ascariasis is approximately 0.12% among patients with biliary tract diseases, with a higher prevalence in endemic areas where it can account for up to 36.7% of biliary and pancreatic diseases. 1, 2

Epidemiological Patterns

Biliary ascariasis shows specific demographic and geographic patterns:

• Geographic distribution:

  • Most common in developing countries in Asia and Latin America
  • Endemic areas include India and other parts of South Asia 2
  • Increasingly seen in developed countries due to population migration 3

• Demographic factors:

  • Female predominance in adult populations 1, 2
  • More common in adults than children for biliary involvement
  • Over 1.4 billion people worldwide are infected with Ascaris lumbricoides, though only a portion develop biliary complications 4

Clinical Significance

Biliary ascariasis represents an important clinical entity:

• It constitutes a significant cause of biliary and pancreatic disease in endemic regions 2
• It can lead to serious complications including:
  • Recurrent biliary colic (95% of cases)
  • Recurrent pyogenic cholangitis (68%)
  • Acalculous cholecystitis (23%)
  • Pancreatic disease (15%) 2
  • Potential for biliary obstruction, cholangitis, and pancreatitis 3

Diagnostic Approaches

The diagnosis of biliary ascariasis relies on several modalities:

• Endoscopic retrograde cholangiopancreatography (ERCP):

  • Highest diagnostic accuracy (87.5% in reported series) 1
  • Allows both diagnosis and therapeutic intervention 4

• Ultrasonography:

  • Non-invasive diagnostic tool with 40% sensitivity 1
  • Useful for follow-up after treatment 4

• Clinical indicators:

  • Vomiting of roundworms during biliary colic (48% of cases) can suggest the diagnosis 2
  • Laboratory findings may include leukocytosis and elevated liver enzymes 1

Management Considerations

Treatment approach should follow a stepwise algorithm:

1. Conservative management as first-line treatment:

   • Intravenous fluids
   • Nasogastric decompression
   • Antibiotics
   • Anthelmintic agents after acute symptoms subside 1

2. Endoscopic intervention when indicated:

   • Worm extraction through ERCP
   • Removal via T-tube or nasobiliary drainage 1, 5

3. Surgical intervention reserved for complications:

   • Uncontrolled sepsis
   • Suppurative cholangitis
   • Cases where worms are trapped in ducts forming stones 1, 2

Prognosis and Prevention

• Prognosis is generally good with proper diagnosis and treatment 1
• Regular follow-up with anthelmintic agents is recommended to prevent reinfection 1
• Most patients (90%) recover with symptomatic treatment followed by anthelmintic therapy 2

Clinical Pitfalls to Avoid

• Misdiagnosis as gallstone disease or other biliary conditions
• Delayed treatment leading to complications
• Failure to consider biliary ascariasis in patients from endemic areas presenting with biliary symptoms
• Inadequate follow-up leading to recurrence

Physicians should maintain awareness of biliary ascariasis as a potential cause of biliary colic, particularly in patients from endemic regions or with relevant travel history 5.