[Elizabeth_Zeibig]_Clinical_Parasitology__A_Practi(z-lib.org)

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CHAPTER 10 The Cestodes
(CNS) involvement. Paramomycin and quinacrine
hydrochloride (Atabrine) may also be used
as alternative treatments.
Prevention and Control
There are three important prevention and control
measures to alleviate Taenia spp.: exercising
proper sanitation practices, thorough cooking
of beef and pork prior to consumption, and
promptly treating infected persons. Although
each of these measures, on their own, will break
the organism’s life cycle if instituted, a combination
of all three provides for an overall cleaner
environment and healthier populations.
Notes of Interest and New Trends
Humans have been known to contract a human
tissue infection associated with T. solium known
as cysticercosis. This occurs when a human accidentally
ingests the T. solium eggs that are passed
in human feces. Food, water, and soil contamination
are likely methods of transmitting the eggs
from person to person. Once inside the body, the
eggs lose their outer covering, allowing the developing
oncosphere to invade the bloodstream and
tissues, primarily the voluntary muscles. Although
some patients remain asymptomatic, symptoms
may vary by location of the infection. Manifestations
of brain infections (neurocysticercosis) are
common and may include headache, seizures,
confusion, ataxia, and even death. Treatment is
available, including surgical removal and medication.
Immunologic tests are available for the
diagnosis of cysticercosis, including indirect
hemagglutination and the enzyme-linked immunosorbent
assay (ELISA). Prevention measures
are similar to those for the Taenia species, thorough
cooking of pork and using proper sanitation
practices.
Taenia saginata asiatica (Asian Taenia) or
Taenia asiatica infections have been reported
from various locations in Asia. Most reported
cases have been acquired by eating raw pig liver,
although consumption of cattle and goat has also
been implicated. Morphologically, T. asiatica
contains a sunken rostellum and two rows of
hooklets, unlike T. saginata. Molecular studies
have indicated that the organism differs from
both T. saginatia and T. solium. Unlike infections
with T. saginata or T. solium, multiple adults
may be present in T. asiatica infection. Infected
individuals may be asymptomatic or may experience
abdominal pain, nausea, weakness, weight
loss, and headaches. The treatment of choice is
praziquantel.
Quick Quiz! 10-4
Which of the following are key distinguishing factors
in differentiating an infection between T. saginata
and T. solium? (Objective 10-9)
A. Egg morphology and number of uterine branches
in proglottid
B. Presence of hooklets on scolex and egg
morphology
C. Presence of hooklets and number of uterine
branches in proglottid
D. Egg morphology and presence of suckers on
scolex
Quick Quiz! 10-5
The primary means of developing an intestinal infection
with Taenia spp. is via which of the following?
(Objective 10-5)
A. Skin penetration of larvae
B. Ingestion of raw or poorly cooked meat
C. Egg consumption
D. Drinking contaminated water
Quick Quiz! 10-6
Which is the preferred drug for treating intestinal
infection by Taenia spp.? (Objective 10-7)
A. Praziquantel
B. Penicillin
C. Nicolasamide
D. Pentamidine