Ankara et.al. Diffuse parenchymal neurocysticercosis Health Renaissance 2015;13(3): 181-184
Case Report
Diffuse parenchymal neurocysticercosis S Ankara, K Dhungel, K Ahmad, M K Gupta, A Panwar Department of Radiodiagnosis and Imaging B.P. Koirala Institute of Health Sciences, Dharan, Nepal
Abstract Neurocysticercosis is the commonest parasitic manifestation of brain and the leading cause of seizure in the developing world. It is caused by the ingestion of Taenia solium eggs through contaminated food and especially pork meat. Computed tomography and magnetic resonance imaging are the modality of choice for diagnosis of neurocysticercosis. We report a case of 65 years old male presented with complaint of seizure, which was diagnosed as diffuse parenchymal neurocysticercosis on computed tomography scan of brain. Keywords: Computed tomography, neurocysticercosis, taenia solium Introduction
disorders. The clinical manifestations vary
Encystations of the larvae of Taenia solium
with the number, size, location and stage of
(pork tapeworm) in the tissues is known as
cysticerci as well as the intensity of the host’s
cysticercosis.
immune response.3
Encystation
of
this
pork
tapeworm in central nervous system is called neurocysticercosis (NCC) and is endemic in
Case report
developing countries. It is considered as the
A 65 years old male presented with multiple
commonest parasitic manifestation of the
episodes of generalized tonic-clonic seizure.
central nervous system leading to seizure in
There was no family history of epilepsy. No
the developing world.1,2 Clinically it can
history of trauma. Physical examination was
manifests
normal and showed no neurologic deficits.
hypertension, cerebellar
as
epilepsy, focal
ataxia,
intracranial
neurological cognitive
signs,
Laboratory tests revealed mild leukocytosis.
decline,
Computed Tomographic (CT) scan of brain
symptoms of hydrocephalus and psychiatric
was
done.
Axial
section
non-enhanced
followed by contrast-enhanced CT of the
Address for correspondence Dr. Sajid Ansari Assistant Professor Department of Radio Diagnosis and Imaging B.P. Koirala Institute of Health Sciences, Dharan Email:
[email protected]
brain revealed multiple, small, rounded, well defined hypodense lesions diffusely scattered in 181
brain
parenchyma
involving
bilateral
Ankara et.al. Diffuse parenchymal neurocysticercosis Health Renaissance 2015;13(3): 181-184
fronto-temporo-occipito-parietal
lobes
and
scattered in brain parenchyma involving
bilateral cerebellar hemispheres (Figure 1, 2,
bilateral
3 and 4).
lobes and bilateral cerebellar hemispheres.
Figure 1, 2, 3 and 4: Axial section CT image
Calcified mural nodules within some of the
of brain showing multiple, small, rounded,
lesions, suggesting calcified scolex seen in
well defined hypodense lesions diffusely
left
fronto-temporo-occipito-parietal
occipital
Fig. 1
Fig. 2
Fig. 3
Fig. 4
and
right
parietal.
Lesions were also seen in pons, midbrain,
evidence of hydrocephalus. The patient was
thalamus, basal ganglia and corpus callosum.
managed conservatively with albendazole,
Calcified mural nodules are seen within some
dexamethasone and phenytoin. At 3-month
of the lesions, suggesting calcified scolex
follow-up, there was no seizure and the
(Figure 2, 3 and 4) and mild perilesional
patient was on phenytoin.
edema in some of the lesions. There was no 182
Ankara et.al. Diffuse parenchymal neurocysticercosis Health Renaissance 2015;13(3): 181-184
Discussion
According to Escobar classification, NCC is (pork
categorized into four stages.7 Stage 1
tapeworm) through contaminated food results
(vesicular stage) is the active or viable stage.
in cysticercosis.4 When the eggs reach the
CT scan shows round, hypodense areas of
intestine,
varying
Ingestion of Taenia solium
their
protective
eggs
coatings
are
in
sizes
and
numbers,
with
destroyed by biliary and pancreatic enzymes
hyperdense eccentric mural nodule within (2-
and released as oncospheres. Then they
4 mm in size) and no perilesional edema. No
traverse the intestinal wall and enter the
evidence of enhancement on contrast study.
bloodstream and are carried to the tissues of
On MRI (magnetic resonance imaging), it
the host and established as larvae. The
appears as CSF-like intensity signal on all
oncospheres lodged in the central nervous
sequences with hyperintense mural nodule
system develops into cysticercus cellulosae
within.
4
This sets up an
Stage 2 (colloidal-vesicular stage) is the
inflammatory reaction in the CNS which
transitional stage. The cysticercus loses the
produces seizures and epilepsy.2
ability to control the host's immune response
Neurocysticercosis is further divided into
and the cyst wall becomes infiltrated and is
parenchymal and extraparenchymal disease.
surrounded by predominantly mononuclear
The CSF (cerebrospinal fluid) migration of
cells. On CT and MRI, it appears as ring
cysticerci to the ventricles, cisterns and
enhancing lesions with perilesional edema.
subarachnoid space or within the eyes or
Stage 3 (granular-nodular stage) is also the
spinal
transitional stage in which host's immune
and known as NCC.
cord
is
called
extraparenchymal basal
response further progresses with collapse of
cisternal NCC along with hydrocephalus has
the cyst cavity. On CT, it appears as small,
disease.
The
intraventricular
mortality rate of about 50%.
and
3
hyperdense,
rounded,
nodular
lesion
Patients with cysticercosis are typically aged
surrounded by edema. On MRI, it appears as
10-40 years. However, cases have been
signal
described in every age group. There is no
perilesional edema.
3
void
in
all
the
sequences
with
gender predilection. Postmortem studies in
Stage 4 (calcified nodular stage) is the
endemic
inactive
areas
neurocysticercal
suggest
that
infections
80%
of
stage
formed
as
a
result
of
dystrophic calcification of the necrotic larva. It
are
asymptomatic.6 Consequently, many cases
is
are never diagnosed or are found incidentally
perilesional edema on CT and on MRI, it is
during imaging procedures. 183
seen
as
calcified
nodule
with
no
Ankara et.al. Diffuse parenchymal neurocysticercosis Health Renaissance 2015;13(3): 181-184
seen as signal void in all the sequences with
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