Sneddon's syndrome is a form of arteriopathy characterized by several symptoms, including: * Severe, transient neurological symptoms or

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

Livedo reticularis Livedo reticularis is a common skin finding consisting of a mottled reticulated vascular pattern that appears as a lace-like purplish discoloration of the skin. The discoloration is caused by reduction in blood flow (ischemia) through the arter ...

, or

livedo racemosa Livedo racemosa is a skin condition with persistent red or violet discoloration, characterised by a broken, branched, discontinuous and irregular pattern. It can be restricted to the limbs or diffuse. It is usually the first sign of a systemic vas ...

Signs and symptoms

Sneddon's syndrome generally manifests with stroke or severe, transient neurological symptoms, and a skin rash (

livedo reticularis Livedo reticularis is a common skin finding consisting of a mottled reticulated vascular pattern that appears as a lace-like purplish discoloration of the skin. The discoloration is caused by reduction in blood flow (ischemia) through the arter ...

). Livedo reticularis appears as a bluish-purple, netlike mottling of the skin. Sneddon's syndrome may instead present with

, which involves larger, less organized patches of bluish-purple mottling of the skin. Both are generally found first in the extremities, both worsen in cold and either may occur without Sneddon's syndrome or any other systemic disease. Sneddon's syndrome can be characterized by: transient

amnesia Amnesia is a deficit in memory caused by brain damage or brain diseases,Gazzaniga, M., Ivry, R., & Mangun, G. (2009) Cognitive Neuroscience: The biology of the mind. New York: W.W. Norton & Company. but it can also be temporarily caused by t ...

, transient

aphasia Aphasia, also known as dysphasia, is an impairment in a person's ability to comprehend or formulate language because of dysfunction in specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine, but aph ...

palsy Palsy is a medical term which refers to various types of paralysisDan Agin, ''More Than Genes: What Science Can Tell Us About Toxic Chemicals, Development, and the Risk to Our Children'' (2009), p. 172. or paresis, often accompanied by weakness and ...

headaches A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches. Head ...

, hypertension, transient ischemic attacks (TIA),

, coronary disease and dementia. The skin manifestations may precede the neurologic symptoms by years.

Pathogenesis

Sneddon's syndrome is a progressive, noninflammatory arteriopathy leading to the characteristic skin condition and to cerebrovascular problems, including stroke, transient ischemic attack (TIA), severe but transient neurological symptoms thought to be caused by cerebral vasospasm, coronary disease and early-onset dementia. Progressive compromise of arterial linings in Sneddon's produces clotting, for which high-dose

warfarin Warfarin, sold under the brand name Coumadin among others. It is used as an anticoagulant, anticoagulant medication. It is commonly used to prevent deep vein thrombosis and pulmonary embolism, and to protect against stroke in people who ha ...

is most commonly prescribed, and can also cause the development of systemic arterial plaque when cholesterol levels are normal.

Diagnosis

There are no diagnostic tests on which all Sneddon's patients will have abnormal results, although brain MRI and skin biopsy are often abnormal. The diagnosis is based on a detailed history and physical examination. About 40-60% of patients with the syndrome test positive for antiphospholipid antibodies.

Treatment

Sneddon's patients are generally treated with warfarin, maintaining a high INR of 3–4. Because most will experience significant relief of symptoms after several months of consistent INR in this range, treatment with warfarin is often used as a diagnostic tool.

Epidemiology

Sneddon's syndrome is a rare condition that is usually misdiagnosed. It occurs in families and may be inherited in an

autosomal dominant In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the Phenotype, effect of a different variant of the same gene on Homologous chromosome, the other copy of the chromosome. The firs ...

fashion. Sneddon's syndrome most often becomes apparent in women in their thirties, though cases do occur in men and in children. Generally, Livedo precedes cerebrovascular involvement by roughly ten years, and many years of cerebrovascular involvement precede the development of dementia, when it occurs.

History

It is named for Ian Bruce Sneddon. In 1965, Dr. Sneddon first reported 6 patients with a distinct skin rash and cerebrovascular accidents (strokes).Sneddon's Syndrome was formerly understood to be a type of autoimmune disease called

antiphospholipid syndrome Antiphospholipid syndrome, or antiphospholipid antibody syndrome (APS or APLS), is an autoimmune, hypercoagulable state caused by antiphospholipid antibodies. APS can lead to blood clots (thrombosis) in both arteries and veins, pregnancy-relate ...

, although it has been reclassified as a noninflammatory cerebrovascular disease. It should be considered in patients diagnosed with vasculitis when standard treatments fail.

References

External links

{{Systemic vasculitis Vascular-related cutaneous conditions Rare diseases Syndromes