[Elizabeth_Zeibig]_Clinical_Parasitology__A_Practi(z-lib.org)

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CHAPTER 12 Artifacts and Confusers
Average size: up to 150 m
FIGURE 12-4 Vegetable cell.
FIGURE 12-6 Vegetable spiral, Iron hematoxylin stain,
1000X. Arrow indicates a vegetable spiral artifact. (Courtesy
of Carolina Biological Supply Company.)
FIGURE 12-5 Vegetable spiral.
VEGETABLE CELLS
Vegetable cells may easily be confused with helminth
eggs (Fig. 12-4). These cells are typically
large and roundish oval to irregularly round in
shape and may measure up to 150 µm in size.
Thick cell walls are usually present. The interior
portion of vegetable cells is unorganized and
often appears to consist primarily of large
vacuoles.
VEGETABLE SPIRALS
Vegetable spirals often resemble helminth larvae
in their shape and size (Figs. 12-5 and 12-6).
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. The
ladder consists of a series of rungs that are spaced
closely together.
FIGURE 12-7 Charcot-Leyden crystal.
Quick Quiz! 12-2
Which of the following characteristics can help differentiate
vegetable spirals from helminth larvae?
(Objective 11-1)
A. Presence of head or tail region
B. Ladder-like appearance
C. Characteristic worm shape
D. Length of spiral
CHARCOT-LEYDEN CRYSTALS
Of all of the confusers and artifacts discussed in
this chapter, Charcot-Leyden crystals have the
most clinical significance (Fig. 12-7). They are
typically found in stool or sputum specimens and