Giardiasis

Question 1

What is the cause of Giardiasis?

Answer 1

Giardia lamblia

Question 2

How is Giardia spread?

Answer 2

The faecal oral route

Question 3

What is Giardiasis particularly associated with?

Answer 3

Malabsorption of fat and carbohydrates

Question 4

How does Giardiasis present?

Answer 4

Presentation is of chronic persistent, or recurrent non-bloody diarrhoea with very offensive stools, abdominal distension and weight loss. There may be signs of fat soluble vitamin deficiency.

There may be signs of failure to thrive in children.

Question 5

What is the investigation of choice in Giardiasis and why isn’t stool microscopy used?

Answer 5

The detection of antigens on the surface of the organisms in the stool specimen.

Giardia lamblia is mainly found in the duodenum and likes to just stay there.

THEREFORE

Stool microscopy (for trophozoites and cysts) is insensitive (A single stool examination will identify about 50% of cases, and three stool samples about 90%.)

Swallowed string can also be used to detect it.

Question 6

How is it treated?

Answer 6

Metronidazole