The diagnostic value of skin biopsies in Sneddon syndrome

Background Sneddon syndrome (SS) is defined by widespread livedo reticularis (LR) and stroke. There is no single diagnostic test for SS and diagnosis can be solely based on clinical features. This cross-sectional case-control study aimed to determine the diagnostic value of skin biopsies in SS patients. Materials and methods We studied skin biopsies from patients with a clinical diagnosis of SS or isolated LR. We also studied controls with vitiligo or normal skin. Biopsies were considered standardized if 3 biopsies were taken from the white centre of the livedo and reached until the dermis-subcutis border. Biopsies were scored for features of an occlusive microangiopathy without knowledge of the clinical features. Sensitivity and specificity of the biopsy findings were calculated with the clinical criteria as the reference standard. Results We included 34 SS patients, 14 isolated LR patients and 41 control patients. Biopsies of 17 patients with SS (50%), 4 with isolated LR (31%) and 10 control patients (24%) showed at least one artery in the deep dermis with a thickened vessel wall combined with recanalization or neovascularization (sensitivity 50% and specificity 69% with LR as reference). Standardized biopsies increased the sensitivity to 70%. In a post hoc analysis the combination of an occlusive microangiopathy and the presence of a livedo pattern in the superficial dermis increased the specificity to 92%. Conclusions Standardized skin biopsies can support the clinical diagnosis of SS. An occlusive microangiopathy as the only positive criterion for the diagnosis of SS had insufficient specificity for a definite diagnosis.

Concomitant myocardial injury and valvular disease in Sneddon syndrome: a case report

Background Cardiac involvement in Sneddon syndrome (SS) is rare, the physiopathology is still unclear. We report a first case of SS without antiphospholipid antibodies who had coexisting ischaemia with no obstructive coronary arteries and aortic valve diseases. Case summary A 34-year-old woman with SS without antiphospholipid antibodies, was admitted for aphasia, and paresthaesia with confirmed right opercular ischaemic lesions at brain magnetic resonance imaging. Transthoracic echocardiographic examination showed akinesis of apical segments, moderate aortic valve stenosis, and moderate aortic insufficiency. Coronary angiogram was normal. Cardiac magnetic resonance showed transmural necrosis in the territory of the left anterior descending artery. Seven years later, our patient had no change or progression of myocardial ischaemic lesions or valvular disease. Conclusion We will discuss different hypothesis, diagnosis, treatment, and evolution of cardiac involvement in SS. Close follow-up should be regularly performed for early diagnosis, hence the importance of multimodality imaging, to guide treatment and prevent further complications.

Sneddon syndrome: a comprehensive clinical review of 53 patients

Background The presence of livedo reticularis in patients with ischaemic stroke is associated with Sneddon syndrome (SS). Our objective was to present the clinical features of SS patients and to assess the role of antiphospholipid antibodies (APL). Methods Consecutive patients, diagnosed with SS between 1996 and 2017, were retrospectively reviewed for their demographic, neurological, dermatological, cardiac and extracerebral vascular features. Diagnosis of SS was made only if other causes of stroke were excluded. Patients with and without APL were included and compared for their clinical features. Results Fifty-three patients (79% female) were included, of whom 14 patients were APL-positive. Median age at diagnosis was 40 years. Approximately 60% of the patients had ≥ 3 cardiovascular risk factors. There were 129 previous vascular events (66 ischaemic strokes, 62 TIAs and 1 amaurosis fugax) during a median period of 2 years between the first event and diagnosis of SS. Skin biopsy was positive for SS in 29 patients (67%), mostly showing a thickened vessel wall with neovascularization in the deep dermis. After a median follow-up of 28 months, 4 patients, either on antiplatelet or oral anticoagulation therapy, had a recurrent stroke. There were few statistically significant differences between APL-negative and APL-positive patients, including the number of vascular events before diagnosis. Conclusions SS predominantly affects young women with a relatively large number of cardiovascular risk factors. Clinical features of SS are comparable across different studies. We found no differences in the main clinical features between APL-positive and APL-negative patients.