[Elizabeth_Zeibig]_Clinical_Parasitology__A_Practi(z-lib.org)

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CHAPTER 8 The Nematodes
in immigrants to the United States from known
endemic areas, this organism has been reported
in areas of the South that are mostly rural
and in the Appalachian Mountain region.
Areas of poor sanitation, in which feces are disposed
in the warm moist soil, provide a wonderful
atmosphere for the organism to exist,
especially when participating in the indirect cycle
of reproduction. Those at risk for contracting
threadworm are those who come into skin
contact with contaminated soil. In addition,
persons living in institutions in which sanitation
may be poor, such as psychiatric facilities, are
also at risk.
Clinical Symptoms
Asymptomatic. Patients suffering from only a
light infection often remain asymptomatic.
Strongyloidiasis: Threadworm Infection. The
most common symptoms experienced by patients
suffering from threadworm infection include
diarrhea and abdominal pain. These patients
may also exhibit urticaria accompanied by eosinophilia.
Additional intestinal symptoms may
occur, such as vomiting, constipation, weight
loss, and variable anemia. Furthermore, patients
with heavy infections may develop malabsorption
syndrome. The site of larvae penetration
may become itchy and red. Recurring allergic
reactions may also occur. When the larvae
migrate into the lungs, patients may develop
pulmonary symptoms. Immunocompromised
persons often suffer from severe autoinfections
that may result in the spread of the larvae
throughout the body, increased secondary bacterial
infections, and possibly death.
Treatment
The treatment for a threadworm infection is ivermectin
with albendazole as an alternative.
Prevention and Control
The measures necessary to prevent and control
the spread of S. stercoralis are similar to those
for hookworm. In addition to proper handling
and disposal of fecal material and adequate
protection of the skin from contaminated soil,
prompt and thorough treatment of infected
persons is essential, especially to stop or prevent
autoinfections.
Quick Quiz! 8-16
This diagnostic stage of Strongyloides stercoralis is
best seen in stool using fecal concentration techniques:
(Objective 8-9)
A. Eggs
B. Rhabditiform larvae
C. Filariform larvae
D. Adult worms
Quick Quiz! 8-17
The life cycle of Stronglyoides most resembles that of
which of the following? (Objective 8-12)
A. Pinworm
B. Whipworm
C. Hookworm
D. Threadworm
E. Human roundworm
Quick Quiz! 8-18
The two clinical symptoms most commonly associated
with Trichinella spiralis are which of the following?
(Objective 8-7)
A. Constipation and abdominal pain
B. Vomiting urticaria
C. Diarrhea and vomiting
D. Abdominal pain and diarrhea
Trichinella spiralis
(trick”i-nel’uh/spy’ray’lis)
Common name: Trichina worm.
Common associated disease and condition
names: Trichinosis, trichinellosis.