Discussion
We present a case of acute ischemic stroke associated with
neurosarcoidosis [4]. The stroke’s location pointed to a
small-vessel disease mechanism. Although the patient had risk factors
such as hypertension and polycythemia, the close proximity of the
ischemic lesions to areas of previous leptomeningeal enhancement on MRI
supports the hypothesis that the ischemic events were secondary to
neurosarcoidosis.
Over the past decade, numerous case reports have described acute
ischemic stroke as a rare but important complication of neurosarcoidosis
[5,6]. Small-vessel vasculitis is the most common ischemic subtype
in these cases, with pontine perforating vessels and lenticulostriate
arteries frequently affected. These infarcts tend to be small, often
involving the basal ganglia, thalamus, and brainstem [8], while
rostral supratentorial vessels are less frequently involved [5].
Post-mortem studies indicate that granulomatous vasculitis primarily
targets small vessels, particularly perforating arteries [3,8].
Veins, especially in the periventricular region, may also be involved
[9]. Histological findings often show granulomas extending along
Virchow-Robin spaces in a perivascular distribution, suggesting
mechanisms such as vessel compression or direct arterial wall
involvement as contributors to ischemia [10,11].
The mechanisms underlying stroke in neurosarcoidosis are diverse and
multifactorial. While large-vessel strokes are rare, they may result
from inflammation-induced thrombosis, characterized by
non-circumferential vessel wall involvement, or compression from
adjacent granulomatous lesions [7]. A Moyamoya-like vasculopathy,
unilateral or bilateral, has also been reported [12]. Cardioembolic
strokes secondary to cardiac sarcoidosis are less frequent [13].
Hemorrhagic lesions, although uncommon, are clinically significant and
may arise from inflammatory vascular damage or anticoagulant use. In
some cases, extensive thrombosis involving dual sinuses causes venous
outflow obstruction, further contributing to ischemic or hemorrhagic
complications. These findings underscore the complex interplay of
vascular and inflammatory processes in stroke associated with
neurosarcoidosis.
The treatment of ischemic stroke in neurosarcoidosis consists of two key
components: managing the stroke itself and addressing the underlying
sarcoidosis. For stroke management, antiplatelet monotherapy [14]
and lipid-lowering agents [15] are commonly employed for secondary
stroke prevention. In treating the inflammation associated with
neurosarcoidosis, glucocorticoids remain the first-line therapy, often
yielding rapid improvements [16]. Severe cases may require
pulse-dose intravenous methylprednisolone (1000 mg daily for 3–5 days),
followed by maintenance therapy with oral prednisone (60–80 mg daily).
To reduce the risk of stroke recurrence, long-term maintenance with
steroid-sparing immunosuppressants is often necessary [17, 18].
Monotherapy with agents such as methotrexate or mycophenolate mofetil
has generally been insufficient to achieve remission, with most patients
requiring at least two lines of immunosuppression. TNF-alpha inhibitors,
particularly infliximab, have demonstrated the highest efficacy in
achieving remission. However, infliximab use is associated with
challenges, including side effects such as chondritis, infusion
reactions related to anti-drug antibodies, and potential drug
discontinuation. Relapses have also been reported in patients tapered
off infliximab, underscoring the complexity of treatment.
Key clinical messageNeurosarcoidosis can present as ischemic stroke through small-vessel
vasculitis, requiring early recognition and targeted immunosuppressive
therapy to prevent severe disability.
Author contribution statement
Dr. Suppakitjanusant (Corresponding Author): Conceptualization,
Methodology, Project Administration, Visualization, Writing – Original
Draft, Writing – Review & Editing. Dr. Srifuengfung: Data Curation,
Formal Analysis, Supervision, Visualization, Writing – Review &
Editing.Dr. Chaisrimaneepan: Conceptualization, Data Curation,
Resources, Supervision, Writing – Review & Editing. Dr. Avila:
Conceptualization, Data Curation, Supervision, Writing – Review &
Editing.All authors have reviewed and approved the final version of the
manuscript.