Detection of Intestinal Parasites
Giardia intestinalis

March 2009
So let’s talk about the individual organisms of note. The first that I’d like to discuss is Giardia intestinalis.
You may have heard this parasite referred to by its older names, Giardia lamblia and Giardia duodenalis. Giardia intestinalis is now generally accepted as the preferred name for this organism, but you will still hear the other names used.
This parasite is the most common pathogenic parasite identified in feces in the United States, and is the most commonly diagnosed intestinal parasite by our public health laboratories.
It is a protozoan parasite and it has both Cyst and trophozoite forms. It is also motile and moves with several pairs of flagella. Therefore, it is classified as a flagellate. The cysts and trophozoites measure between10-20 µm in largest dimension and may be detected on both direct and concentrated fecal preparations.
Giardia intestinalis |
Jump to section:
- Introduction
- Intestinal Parasites
- Detection of Intestinal Parasites
- Direct Smear of Fresh Feces
- Direct Smear of Fresh Feces
- Motile Trophozoite of Pentatrichomonas hominis
- Motile Larva of Strongyloides stercoralis
- Feces Concentration
- Concentrated Feces with Saline
- Concentrated Feces Wet Preparation
- Concentrated Fecal Smear Stained with a Modified Trichrome Stain
- Giardia intestinalis
- Additional Tests on Fecal Samples
- Which One to Order?
- Parasitic Investiagation of Stool Specimens Algorithm
- Giardia intestinalis
- Life Cycle of Giardia
- Concentrated Feces Wet Preparation
- Giardia intestinalis - Cyst
- Giardia intestinalis - Trophozoite
- Clinical Presentation
- Epidemiology
- US Risk Factors for Giardiasis
- G intestinalis is Easily Transmitted Because
- Diagnosis of Giardiasis
- Algorithm Close-up
- Giardia Antigen Test, Feces
- Sandwich Assay
- ELISA Microtiter Plate
- Treatment
- Cryptosporidium spp
- Cryptosporidium Life Cycle
- Cryptosporidium - Cyst on Wet Prep
- Cryptosporidium - Cysts with Acid Fast Stain
- Clinical Presentation
- Epidemiology
- Examples of Outbreaks
- Examples of Outbreaks
- Cryptosporidium is Easily Acquired Because
- Diagnosis
- Algorithm Close-up
- Cryptosporidium Antigen Test, Feces
- Treatment
- Less Common Fecal Parasites
- Algorithm Close-up
- References
- Questions?