Recurrent cerebral venous sinus thromboses (CVST's) and livedo reticularis rash-a case of Sneddon syndrome

ABSTRACT

Background Sneddon syndrome is a rare, progressive small and medium-vessel vasculopathy characterized by the clinical occurrence of livedo racemosa and ischaemic cerebrovascular events. Objectives We present the clinical course and management of this rare condition. Methods An 18-year-old female of East Indian descent presented with the following CNS involvement Recurrent Cerebral Venous Sinus Thromboses + Cognitive impairment - Skin Livedo reticularis rash - Eyes Bilateral optic nerves atrophy - CVS Mild to moderate LAD dilation (16/12/2020) - MS Polyarticular arthritis She first presented at 8-years-old with new-onset squint, ataxia and fever and was treated as culture-negative meningitis (CSF white cells 1238 neutrophils, CSF protein 110mg/ dL). At 16-years-old, she presented with expressive aphasia, headache, fever, left earache and was treated as acute mastoiditis. Regarding the recurrent presentations of CVST's there was involvement of left transverse sinus (untreated 2 years ago), then over a 1-month period despite anticoagulation, right transverse sinus with extension into the right sigmoid sinus and left straight and posterior superior sagittal sinus. She presented with headache, vomiting and new-onset seizures (GTCS) prior to these presentations. An extension of this clot after being non-compliant with low-molecular weight heparin for 1 week resulted in a venous infarct with surrounding oedema. She presented with progressive right-sided weakness and expressive aphasia and within 24 hours, encephalopathic with decerebrate posturing in subclinical status epilepticus. She was managed in PICU for refractory status epilepticus and raised intracranial pressure. There is also a family history of early stroke (maternal cousin with CVST at 8yo on long-term anticoagulation). Results Her inflammatory markers continued to increase despite antibiotic coverage at meningitic doses and she was treated for a CNS vasculitis/Catastrophic Antiphospholipid syndrome with IV anticoagulation (UFH), high-dose steroids then IVIG. Her neurological state gradually improved (coma -> vegetative state -> minimally conscious -> conscious). This was followed by Rituximab therapy 375 mg/m2 weekly x4. Her neurological function gradually improved as she was able to verbally communicate and developed anti-gravity movement of the right side. Hypertension and fever also settled, and inflammatory markers steadily decreased post treatment. Investigations ANA, dsDNA, ENA negative pANCA borderline positive but MPO, PR3 Antibodies negative Anticardiolipin antibodies negative (on warfarin) Infectious screen (HIV, Hepatitis, COVID-19 serology, Mantoux test, CSF Acid-fast bacilli) - negative CSF cell count - 33 white cells (neutrophils), protein 183mg/dL Skin biopsy report (26/11/2020) - Neutrophils, lymphocytes of leucocytoclasis seen in vessels of dermis. Thrombosis of fibrinoid necrosis of vessel walls and extravasated red blood cells also seen - Obstructive vasculopathy for clinical correlation;Possible Sneddon syndrome/Antiphospholipid syndrome Conclusions There are few case reports describing the clinical course and treatment of this rare syndrome. In our case, treatment for Catastrophic Antiphospholipid syndrome (steroids, IVIG, rituximab and anticoagulation) was beneficial in improving the clinical outcome.