Ascariasis

General Considerations

• Most common parasitic infestation in the world
  

• Most common in children ages 1 to 10 years
  

• Most often found in distal small bowel
  

• Life cycle
  

  • Infection is through contaminated soil

  • Involves GI tract of host twice

    • First time as egg

  • Migrates through lungs

  • Adult travels up trachea

    • Returns to GI tract for maturation (2 months)  

• Signs and Symptoms  

• Colicky pain

• Hematemesis

• Eosinophilia  

• Imaging findings  

• Long, tubular filling defects, especially in distal small bowel

• The worm ingests barium and the barium may be seen as a thin line of contrast in the center of the worm

  • Especially after the remainder of the barium exits the small bowel.  See below (streak of barium in LUQ):

The worm ingests barium and the barium may be seen as a thin line of contrast in the center of the worm (red arrows)

• Ball of worms
   

• Complications
  

  • Appendicitis

  • Jaundice (if bile ducts are involved)

  • Pneumonia

  • Bowel perforation

  • Mechanical obstruction