[Elizabeth_Zeibig]_Clinical_Parasitology__A_Practi(z-lib.org)

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CHAPTER 10 The Cestodes
uterus. A T. saginata proglottid is typically rectangular,
averaging 17.5 by 5.5 mm; 15 to 30
uterine branches are usually present on each side
of the uterus (Fig. 10-5). In contrast, T. solium
is square in appearance and only contains 7 to
15 uterine branches on each side of the uterus
(Fig. 10-6).
Laboratory Diagnosis
Stool is the specimen of choice for the recovery
of Taenia eggs and gravid proglottids. The scolex
may be seen only after the patient has been
Suckers
FIGURE 10-3 Taenia saginata scolex.
treated with antiparasitic medication. Furthermore,
there is evidence to suggest that specimens
collected around the perianal area using the cellophane
tape prep procedure result in a very high
recovery rate of Taenia eggs. It is important to
note that the eggs of Taenia are identical. To
speciate in the laboratory, a gravid proglottid or
scolex must be recovered and examined.
TABLE 10-2
Taenia spp. Adult: Typical
Characteristics at a Glance
Characteristic T. saginata T. solium
Scolex
Number of Four
Four
suckers
Rostellum Absent Present
Hooks Absent Present;
double
crown
Gravid Proglottid
Appearance,
shape
Longer than wide;
average, 17.5
Somewhat
square
Number of lateral
branches on
each side of
uterus
by 5.5 µm
15-30 7-15
Hooks
Rostellum
Suckers
A
B
FIGURE 10-4 A, Taenia solium scolex. B, Taenia solium scolex, 40×. (Courtesy of Carolina Biological Supply,
Burlington, NC.)