Vol 41 # 3 September 2009 - Kma.org.kw

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Neurosarcoidosis as a First Presentation of Systemic Sarcoidosis: Case Report
September 2009
Fig. 5: Photomicrograph of a lymph node showing extensive
hyalinization with little residual lymphoid tissue. In addition,
there is a non-caseating granuloma consistent with sarcoidosis.
included CXR, brain MRI, and gradual reduction of
the steroid dose.
A follow-up brain MRI done 12 weeks
post-discharge showed, in comparison to the
previous study, a reduction in the leptomeningeal
enhancement, and in the number and size of the
parenchymal sarcoid nodules. The non-enhancing
one cm cystic lesion in the right hippocampus
remained the same but with almost disappearance
of the surrounding vasogenic edema and the
midline shift, (Fig. 6). In addition to the radiographic
improvement, the patient remained fit-free, the
steroid dose was reduced to 5 mg daily, but the dose
of the antiepileptic drugs remained unchanged.
DISCUSSION
NS may affect virtually any part of the nervous
system, resulting in widely variable clinical
presentations. Cranial neuropathy is the most
common with the frequency of peripheral seventh
cranial nerve paresis reaching 40 to 60% [3,6] .
Neurological involvement precedes systemic
manifestations in 31 to 74% of patients, but it may be
the only manifestation in 10 to 17% of patients [2,4] .
NS is a diagnostic consideration in patients
with known sarcoidosis who manifest neurological
complications and in patients presenting de
novo with constellations of symptoms and signs
consistent with the disease. There is no definite
imaging technique or laboratory test that can
prove the diagnosis of sarcoidosis beyond doubt
and a definite diagnosis requires extensive work
up that utilizes radiological, histopathological and
serological tests collectively.
Contrast-enhanced brain CT scan is insensitive,
with normal appearances in up to 30% of cases with
definite NS. Conversely, gadolinium-enhanced
brain MRI is the diagnostic investigation of choice
in suspected case of NS with leptomeningeal
involvement being the most frequent feature [7] .
Fig. 6: MRI brain, gadolinium-enhanced T l
weighted axial
image showing reduction in the size and number of the nodules
seen in the right temporal and left frontal lobes with almost
disappearance of the surrounding vasogenic edema
Despite the emergence of new technologies, a
conventional CXR continues to have a crucial
role for the diagnosis, prognosis, and follow-up
of sarcoidosis. The CXR is abnormal in more than
90% of patients at some point and is often the first
investigation to suggest the diagnosis. Typical
abnormalities (i.e., bilateral hilar lymphadenopathy
with or without parenchymal involvement) are
noted in 50 to 80% of patients [7] . Cerebrospinal fluid
(CSF) analysis maybe normal or may show nonspecific
abnormalities like elevated proteins and
lymphocytic pleocytosis. It is helpful in ruling out
other CNS diseases like infections and multiple
sclerosis [8] . The role of CSF angiotensin converting
enzyme (ACE) is unclear since it is neither sensitive
nor specific for the disease [2] .
In all cases, a biopsy specimen should be
obtained from the involved organ that is most easily
accessible. Lung tissue is usually sampled by means
of fibro-optic bronchoscope with a diagnostic yield
of about 85% [2] . The finding of typical NCG that
stain negatively for AFB is highly suggestive in
the appropriate setting; however, careful further
evaluation is needed to rule out other causes of
granulomatous diseases [8] .
Seizures in NS are estimated to occur in up to
20% of cases and maybe the heralding manifestation
of sarcoidosis [4] . Some series consider seizures a
poor prognostic indicator and associate it with high
mortality [4] . It is worth mentioning that seizure types
affected survival with death being more frequent
(about double) in those with generalized tonic-clonic
(40%) seizures compared with focal variety (20%) [5] .
The use of conventional antiepileptic medications
alone is considered ineffective [2] .
CS therapy for NS has been the mainstay
of treatment for half a century. The rationale
behind its use was to treat the possible subclinical
endocrine impairment, particularly in the pituitary