36 Giant Round Worm

Ascaris Lumbricoides

36.1 Life Cycle

Eggs in stool

Stool into ground.

Eggs in gound for months as they’ve a cuticle

Swallowed into body

Form larvae in abdomen.

Then enter blood, then go to lungs (stay and grow and develop into tiny adults). Crossing into lungs can cause Loefflers

Coughed up and swallowed into gut

36.2 Epi

1/4 of all humans may be infected!

Impoverished children in the tropics

36.3 Clinical Features

Early infection: Usually asymptomatic, sometimes eosinophila pneumonitis.

Later infection: Still usually asymptomatic. But then sometimes found incidentally during colonoscopy.

Maybe some nausea, abdo pain, diarrhoea, malnutrition. Association or cause though?

36.3.1 Complications

• Bowel obstruction/volvulus
• Ectopic Adults: Migrate up biliary tree (pancreatitis/sepsis), peritoneum

36.4 Diagnosis

• Find eggs on stool (usually found as aults lay so many)
• Ultrasound of gallbladder

36.5 Treat

Careful to not kill too quickly as you could maybe cause bowel obstruction with multiple worms. Ivermectin can do this.

Albendazole should be safe enough.

36.6 Blah

600 million people have ascaris. Most ascaris completely asymptomatic.

40cm long

Each worm lays 200,000 eggs/day

Eggs hatch into larvae in soil (this takes 1-4 weeks)

Ingested larvae migrate gut, blood, lungs, gut (up to 10 weeks)