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Giardiasis (cont.)

Giardia: How Is Giardiasis Diagnosed?

There are multiple ways to diagnose giardiasis; the following is a list of tests doctors utilize to diagnose the disease. Some individuals with acute giardiasis are relatively easy to diagnose while others may require more invasive tests.

Stool exam

  • The most common way to diagnose giardiasis is by the visualization of the Giardia lamblia cysts by experienced laboratory professionals. The cysts are detected more than half the time in the first stool specimen examined. Most of the time, the cysts are detected after three stool specimens have been examined. So more than one specimen may be required.
  • Another method of diagnosis that is commonly used as a screening tool in outbreaks or in daycare centers is antigen assay of stool. This method detects a certain protein found in the wall of Giardia lamblia. A stool sample is mixed with a solution that detects the cysts in the stool.

String test

  • The string test involves swallowing a fuzzy string enclosed in a gelatin capsule. The free end of the string is taped to the person's cheek. Once swallowed, the string collects secretions and mucus from the small bowel. Four hours later the string is pulled back out and examined for organisms.

Aspiration and biopsy

  • This is the most invasive method of diagnosis. After passage of a small tube (endoscope) through the person's mouth and stomach into the small bowel, the doctor removes a small amount of tissue for examination. This method is reserved for difficult cases in which the cause of diarrhea cannot be determined using other methods. It allows for visualization of all abnormalities of the small intestine, which may cause diarrhea including giardiasis.

Giardia: Giardiasis Self-Care at Home

  • Drink fluids such as sports drinks, diluted fruit juices, flat soda (such as 7-Up or ginger ale, none with caffeine), broth, soups, or preparations such as Pedialyte for children. Fluids should be taken in small amounts frequently throughout the day. Avoid fluids containing caffeine.
  • Suck on ice chips to keep from becoming dehydrated if you cannot keep fluids down.
  • After 12 hours, the diet can be advanced to bland foods such as potatoes, noodles, rice, toast, cereal, crackers, and boiled vegetables. Avoid spicy, greasy, and fried foods.
  • After stools become formed, return to a regular diet. Avoid milk for several weeks.
Medically Reviewed by a Doctor on 10/26/2016

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Giardiasis »

Giardia lamblia was originally identified by von Leeuwenhoek in the 1600s and was first recognized in human stool byVilem Dusan Lambl (1824-1895) in 1859and by Alfred Giard (1846-1908) after whom it is named.

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