Laboratory: Artifacts and Confusers Flashcards
There are a number of structures that closely resemble parasites, but in reality, are not. They are termed as _
Artifacts and Confusers
These are often mistaken for amebic cysts
Polymorphonuclear white blood cells (WBCs)
Polymorphonuclear white blood cells (WBCs), are often mistaken for amebic cysts, especially those _
E. histolytica
WBCs are usually present in patients suffering from
Ulcerative colitis
Bacterial dysentery
Intestinal amebiasis
These WBCs have a _ to _ nucleus
Two-to-four lobed
Protozoan nuclear inclusions
Karyosomes
Peripheral Chromatin
Mononuclear WBCs are also known as
Macrophages
Monocytes
_ may closely resemble the E. histolytica trophozoite
Mononuclear WBCs
Mononuclear WBCs may closely resemble the
E. histolytica trophozoite
The macrophage has one __ that is often _ on examination
Irregularly-shaped nucleus
Absent
These may be seen in the macrophages
Red-staining round bodies
Thick-walled pollen grains resemble the egg of _ but _
Taenia spp.
smaller
_ resemble the egg of Taenia spp. but smaller
Thick-walled pollen grain
Pollen grains may appear
Round or symmetrically-lobed
_ may easily be confused with helminth eggs
Vegetable cells
The _ portion of vegetable cells is _ and often appears to consist primarily of _
Interior
Unorganized
Large vacuoles
_ often resemble helminth larvae in shape and size
Vegetable spirals
Unlike helminth larvae, however, vegetable spirals do not have a _
Head or tail region
Vegetable spirals are readily distinguished from parasitic forms by their
Ladder-like appearance
Of all of the confusers and artifacts, _ have the most clinical significance
Charcot-Leyden Crystals
The presence of these diamond-shaped crystals, which develop from _
Eosinophil breakdown products
The round to ovals yeast cells measure _ and may be confused with _
4-8μm in size
Protozoan cysts
Size of Entamoeba hartmanni
5-12μm
Size of Entamoeba nana
4-12μm
Size of Entamoeba hominis
3-10μm
There is a considerable resemblance of a yeast cell to the
oocysts of Cryptosporidium
Yeast may be easily distinguished from parasites when seen in their
Budding stage
_ may also resemble helminth larvae
Plant hair
In addition, plant hair may appear to have a
Nondescript internal structure
Upon further examination, plant hair does not have diagnostic structures, such as:
Buccal cavity
Esophagus
Intestine
Genital primordium
Head or tail region
_ may range in diameter from _ and resemble helminth eggs, particularly an _
Plant material
12 -150μm
Ascaris lumbricoides
Plant material is often rough in appearance and may have hairs known as
Pseudocilia
_ often show a striking resemblance to amebic trophozoites in size and shape
Epithelial cells
The cytoplasm of epithelial cells is usually
Smooth
Contains no inclusions
Similarities of epithelial cells and amebic trophozoites
Have a single nucleus
Often show a distinct cell wall
_ may be similar to the size and shape of protozoan cysts
Fungal elements
The _ easily distinguishes these artifacts from parasitic forms
Lack of interior structure
Round to irregular round-shaped starch cells also referred to as
Starch granules
Starch granules measure less than _ and may appear at first glance to be protozoan cysts, particularly those of _ and _
10μm
E. hartmanni
E. nana
These starch cells are readily differentiated from parasitic forms because they lack
Intestinal structure
In addition, starch cells may be differentiated from parasites because of their _ appearance with _
Dark blue-black
Iodine
_ often appear on Giemsa-stained blood smears and may be mistaken for _ especially the _
Clumped or fused platelets
Malarial parasites
Young trophozoite form
Unlike a malarial parasite, which typically appears as a _ with a _, clumped or fused platelets appear in _.
Blue cytoplasm
Red chromatin
Various shades of purple
_ may be visible on blood smears and may be mistaken for _
Giemsa-stain precipitate
Malarial parasites
Stain precipitate is usually _ in color than malarial parasites
Bluer
_, such as _ or _, may be present on Giemsa-stained blood smears.
Red blood cell abnormalities
Howell-Jolly Bodies
Cabot’s rings
These abnormalities may be easily distinguished from malarial parasites by their
Different staining characteristics
