Cysticercosis,
an infection by the larval stage (bladder worm) of Taenia solium,
the pork tapeworm, prevails where uncooked pork is eaten.
The adult
T. solium is acquired by eating pork infected with cysticerci -
that is measly pork.
Pig acquire cysticerci by ingesting eggs of T.
solium shed in human faeces.
This normal cycle,
although a public health problem, is essentially benign for both
humans and pigs.
However, when humans accidentally ingest the eggs from
human faeces and become infected with cysticerci, the consequences may
be catastrophic.
The eggs
release oncospheres, which penetrate the wall of the gut, enter the
blood stream, lodge in tissue, encyst, and differentiate to cysticerci.
The cysticercus, a spherical, milky white cyst about 1 cm in
diameter, contains fluid and an invaginated scolex with birefringent
hooklets.
The cysticerci remain viable for an indefinite period and
provoke no inflammation but compress adjacent tissue as they grow. The
cysticercus dies, leading to a granulomatous reaction with eosinophils,
after which the lesion becomes scarred and calcified.
Cysticerci in
the retina may lead to blindness.
Massive
cysticercosis of the brain causes convulsions and death, and in the
heart may cause arrhythmias and sudden death. An aberrant cysticercus, called racemose cysticercus, can also be fatal. It is
sterile (without a scolex) and limited to the brain, and has an
arborizing growth that produces a large, grapelike mass several
centimeters in diameter.Racemose
cysticercus in human brain. A case report.Am
J Trop Med Hyg. 1981 May;30(3):620-4
The diagnosis
is made from the morphology of the excised cyst.
Serologic tests are
helpful but do not exclude echinococcosis.
A history of tapeworm
infection in the patient is significant because autoinfection is
possible.
Treatment of muscle disease is with praziquantel.
Neurocysticercosis:
Image1
;
Image2
;
Image3
;
Image4
;
Image5 .(Dr
Tsutsumi)
Neurocysticercosis is the most common helminthic disease of the
nervous system and currently represents a major public health problem
in developing countries of Latin America, Asia, and Africa, as well as
in industrialized nations with a high immigration rate of people from
endemic areas.
The disease
occurs when humans become the intermediate host in the life cycle of
Taenia solium by ingesting its eggs from contaminated food.
Neurocysticercosis is pleomorphic in its presentation due to
individual differences in the number, size, and location of the
parasites, as well as differences in the severity of the host's immune
reaction to the parasite.
Epilepsy, focal
neurological signs, and intracranial hypertension are the most common
clinical manifestations of the disease.
The diagnosis of
neurocysticercosis is based on clinical data, neuroimaging
abnormalities, and the results of immunological tests. Two drugs,
albendazole and praziquantel, are cysticidal and destroy most
intracranial parasites ; however, surgery may be necessary in the
management of some forms of the disease, particularly hydrocephalus
and intraventricular cysts.
Cysticercosis in
an Egyptian mummy:
Short
report: cysticercosis in an Egyptian mummy of the late Ptolemaic
period.Am
J Trop Med Hyg. 2006 Apr;74(4):598-9
|
