What Is Sneddon Syndrome?

  • Dafydd Thomas MSc, Genomic Medicine, The University of Manchester, UK
  • Gregorio Anselmetti Bachelor of Science - BSc, Neuroscience. University of Warwick
  • Ellen Rogers MSc in Advanced Biological Sciences, University of Exeter


Sneddon syndrome is a rare medical condition that affects our blood vessels, mainly the smaller and medium-sized ones. At first glance, this condition might appear as a blue, net-like pattern on the skin called "livedo reticularis", but it's more than just a skin issue. Inside the body, Sneddon syndrome can lead to problems in the brain, causing mini- or even full-blown strokes. Some people with this syndrome also experience headaches, dizziness, and high blood pressure. While Sneddon syndrome has its own unique set of symptoms, it shares some similarities with other conditions, like lupus. In this article, we'll break down the key facts about Sneddon syndrome, helping you understand its causes, effects, and importance.1

Understanding sneddon syndrome

Sneddon syndrome (or SS) is a condition that mainly affects the health and function of the small to medium-sized blood vessels. Over time, these vessels weaken, causing certain distinctive signs and symptoms to emerge:

  • Livedo Reticularis: Usually, in one's teens or twenties, a person might notice blue, lace-like patterns appearing on their skin, mainly referred to as livedo reticularis. It's like a roadmap of veins surfacing, mostly visible on the limbs and trunk.1
  • Neurological complications: As individuals reach adulthood, they may experience symptoms linked to their brain's declining blood supply. This can range from mini-strokes, known medically as transient ischemic attacks, to more severe strokes. These episodes can manifest as sudden confusion, difficulty speaking, or even temporary paralysis of one side of the body.1

But here's where it gets tricky: that unique skin pattern isn't just a sign of Sneddon syndrome. It can also be a symptom of other conditions, like polyarteritis nodosa, systemic lupus, and central thrombocythemia. Each of these conditions can also come with the risk of neurological symptoms or strokes. This overlap makes early and accurate diagnosis crucial.

Occurrence and genetics

Sneddon syndrome is very rare, with approximately 1 in every 250,000 people being diagnosed with it each year.1 Whilst anyone can develop this syndrome, it seems to be more common in individuals assigned female at birth and between twenty and forty years of age. Indeed, 8 out of 10 patients with Sneddon syndrome are female.1

Digging deeper into its roots, we see that Sneddon syndrome is a genetic disease. It's categorised as an autosomal recessive disease, which means that an individual must inherit two copies of the defective gene (one from each parent) to develop it. Researchers have identified a connection between SS and mutations in the CECR1 gene.2 This discovery offers hope for better diagnostic techniques and potential treatments in the future.

Spotlight on symptoms: recognising Sneddon syndrome

Cardiovascular symptoms

The cardiovascular system, including our heart and blood vessels, often gives the first hint. Patients may experience:

  • Hypertension: elevated blood pressure, which can have multiple causes, is commonly seen in SS patients.3
  • Cerebrovascular episodes: this involves interruptions in the brain's blood supply, which can either be due to blockages (ischemic) or bleeding (hemorrhagic).3

Dermatological (skin) symptoms

The skin often serves as a visual storyboard of what's happening beneath:

  • Livedo racemosa: This unique skin pattern, primarily seen on the trunk and legs, looks like a web of blue or purple discolourations.3
  • Skin biopsy: On a microscopic level, a closer look at the skin might reveal blockages in small arteries, a condition called occlusion. There's also evidence of the innermost layer of these arteries thickening, known as intimal proliferation.3

Neurological symptoms 

The neurological manifestations of SS can be diverse, ranging from subtle to severe:

  • Headaches and changes in your vision: these are often the early, milder signs that something's amiss.3
  • Severe symptoms: In some patients, more alarming symptoms can develop, such as seizures (caused by uncontrolled electrical activity in the brain), hemiplegia (paralysis of one side of the body), or even a decline in thinking skills. 3

Diagnosing sneddon syndrome

Diagnosing SS isn't straightforward. It involves:

  • Blood tests: These are the first line of inquiry, searching for any telltale markers that might hint at SS.1
  • Heart check-up: A thorough heart assessment can rule out any cardiovascular abnormalities potentially linked to the syndrome.1
  • Brain imaging:
    • MRI: Think of it as a deep dive into the brain, bringing even minute changes to light.1
    • Cerebral angiography: This imaging technique zeroes in on the brain's blood vessels, looking for any blockages or unusual patterns.1
  • Skin biopsy: A deeper exploration of skin tissue can give crucial information about the disease's presence and progression.1 A closer look at the skin might reveal blockages in small arteries, a condition called occlusion. There's also evidence of the innermost layer of these arteries thickening, known as intimal proliferation.3
  • Cerebrospinal fluid test: While typically normal, this test provides an extra layer of diagnostic clarity.1

Diagnosing Sneddon syndrome is like solving a jigsaw puzzle, with each test piece needing to fit together to create a clear picture. It often takes a combination of dermatological patterns, neurological symptoms, imaging tests and medical history to confidently make a diagnosis.

Tailoring the treatment

In a study that followed people with Sneddon syndrome for an average time of 6.2 years, 9.5% of those individuals died therefore managing Sneddon syndrome requires a dynamic, personalised approach:

  • Addressing skin issues: Nifedipine is often used to relieve painful skin marks or lesions.1
  • Guarding the brain: to protect against cerebrovascular events, doctors might prescribe aspirin or other blood thinners.1
  • Tackling neurological concerns: treatments like intravenous cyclophosphamide (a chemotherapy drug) have shown promise in treating severe neurological symptoms. 1
  • Immunosuppressants and corticosteroids: While these can be beneficial, you must take caution when using them. Their long-term use needs to be carefully weighed against potential side effects. 1

When it comes to treating Sneddon syndrome, two things are crystal clear: Treatment needs to be tailored to the individual, and regular medical appointments and checkups are vital in managing this complex condition.


Sneddon Syndrome is a rare disease, but is one that highlights the importance of both early and comprehensive diagnoses and patient-tailored treatments. With its association with various skin symptoms, cardiovascular anomalies, and neurological manifestations, Sneddon syndrome demonstrates the intricacy and importance of our body’s vascular system. As research progresses, it's hoped that more definitive treatments and diagnostic tools will emerge. For now, recognising its symptoms and maintaining regular medical consultations stand as our best line of defence.


What is sneddon syndrome?

Sneddon Syndrome (SS) is a rare medical condition affecting small to medium-sized blood vessels. It is often marked by a unique skin pattern (livedo reticularis) and cerebral ischemia events, like mini-strokes or strokes.

Who is most affected by sneddon syndrome?

SS primarily affects individuals assigned female at birth, especially those between the ages of 20 to 42. Around 80% of diagnosed cases are in individuals assigned female at birth.

Is sneddon syndrome genetic?

Yes, Sneddon Syndrome can have genetic roots. It is associated with mutations in the CECR1 gene and is categorised as an autosomal recessive disease.

Can sneddon syndrome be cured?

Currently, there's no cure for SS. However, treatments can manage symptoms and reduce the risk of complications, such as strokes.

How is sneddon syndrome diagnosed?

Diagnosing SS involves a combination of blood tests, heart assessments, brain imaging, skin biopsies, and cerebrospinal fluid tests.

Is it dangerous?

If left untreated, SS can lead to serious complications like strokes. However, with proper diagnosis and management, many of these risks can be mitigated.


  1. Wu S, Xu Z, Liang H. Sneddon’s syndrome: A comprehensive review of the literature. Orphanet J. Rare Dis. 2014;9:215. Doi: 10.1186/s13023-014-0215-4
  2. Zhou Q, Yang D, Ombrello AK, Zavialov AV, Toro C, Zavialov AV, et al. Early-onset stroke and vasculopathy associated with mutations in ADA2. New Eng. J. Med. 2014;370:911–20. doi:10.1056/nejmoa1307361
  3. OMIM. #182410 Sneddon Syndrome; SNDNS [Internet]. [cited 2023 Oct 19]. Available from: https://www.omim.org/entry/182410
This content is purely informational and isn’t medical guidance. It shouldn’t replace professional medical counsel. Always consult your physician regarding treatment risks and benefits. See our editorial standards for more details.

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Dafydd Thomas

MSc, Genomic Medicine, The University of Manchester, UK

As a Genomic Medicine student pursuing an MSc at Manchester University, my academic journey is rooted in the realm of biochemistry, with a specialized focus on genetics and the intricacies of rare diseases. Throughout my academic pursuits, I've gained valuable insights into the field of genomics and its applications in medicine. I am committed to sharing advancements in genomic medicine and to delve into cutting-edge research and emerging technologies. With a keen interest in the genetic nuances of rare diseases, I aspire to contribute meaningfully to the field and bridge the gap between genomic knowledge and its clinical implications.

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