Multiple Aneurysms and Cerebral Infarction in a Patient with Sneddon Syndrome

Abstract

A 16-year-old girl presented to the emergency department with dizziness, slurred speech, dysphagia, and right-sided limb weakness for 3 days. She manifested patchy, violaceous skin discoloration on the lower legs 6 years earlier, more prominent when standing or exposed to cold, which was diagnosed as livedo racemosa (LR) through skin biopsy (Fig 1A). Five months earlier, she presented with transient slurred speech. Her growth and development were normal, with no history of any cerebrovascular risk factors, nor any family history.

Laboratory tests yielded positive results for antinuclear antibodies, with a nuclear particle type titer of 1:1,000. The test ratio of dilute Russell viper venom time was 1.35. The levels of anticardiolipin antibodies, anti-beta 2-glycoprotein I, and other laboratory examinations were all within the normal range.

Magnetic resonance imaging showed new infarction in the left pon, along with multiple old infarct lesions in bilateral basal ganglia (Fig 1B and 1C). Susceptibility-weighted imaging showed multiple minimal hypointense spots (Fig 1D-1F). Computed tomography angiography showed a vascular saccular protuberance anterior to the right peduncle (Fig 1G). The digital subtraction angiography revealed multiple intracranial miliary aneurysms (Fig 2A-2D). Among them, the left angular branch aneurysm was the largest (Fig 2A and 2B). A skin biopsy was performed on the right leg and diagnosed as LR.

Considering the risk of bleeding due to multiple intracranial aneurysms, aspirin was used, not anticoagulants. Rituximab was given as immunosuppressive therapy 1 month later, after which the percentage of peripheral B-lymphocyte subsets reduced to 0.04%, followed by hydroxychloroquine. Two months after stroke, the left angular branch aneurysm was treated by endovascular embolization (Fig 2E and 2F). Laboratory tests showed the antinuclear antibodies and lupus anticoagulants returned to the normal range.

At 6-month follow-up, the patient abruptly manifested dysarthria, right central facial paralysis, and right-sided hemiparesis. Magnetic resonance imaging disclosed acute infarction in the left basal ganglia (Fig 1H). Digital subtraction angiography showed multiple aneurysms, among which the aneurysms in the genu segment of the right anterior cerebral artery and the sylvian segment of the right middle cerebral artery were larger than before (Fig 2G and 2H). Given the progression of the disease, glucocorticoid therapy was given, followed by rituximab, as the percentage of peripheral B-lymphocyte subsets rose to 7.73%.

Sneddon syndrome (SS) is a rare neurocutaneous syndrome that progresses slowly, and is identified by generalized patchy, bluish-purple LR, as well as recurrent cerebrovascular events. The histopathology is remarkable noninflammatory thrombotic vasculopathy involving medium and small arteries. SS with aneurysm is a rare condition, with only 4 cases reported, 2 of which were a single cerebral aneurysm.^1-4 This case report was the first to describe the occurrence of multiple intracranial aneurysms and cerebral infarctions in SS, providing further evidence that SS may lead to extensive cerebrovascular abnormalities. The pathophysiological mechanism of aneurysm in SS is still unclear, which may be related to the vascular wall injury associated with antiphospholipid antibodies,⁴ angiogenesis, and collateral formation after chronic cerebral hypoxia.² Furthermore, multiple minimum hypointense spots in susceptibility-weighted imaging may also indicate the possibility of multiple aneurysms, rather than microbleeds or calcification. Recognition of aneurysms is important for the choice of antithrombotic treatment. Thus, more attention should be paid to comprehensive examinations for cerebral aneurysms in patients with SS (Figs 1 and 2).

X.Z., Q.Z., and Y.J. contributed to the conception and design of the study; X.S., X.Z., Q.Z., and Y.J. contributed to the acquisition and analysis of data; X.S., and Q.Z. contributed to drafting the text or preparing the figures.

Nothing to report.