Case Report: Diagnosing Sneddon Syndrome

Discussion 

Sneddon syndrome is a rare, non-inflammatory vasculopathy, typically characterized by livedo racemosa, as well as such complications as cerebral infarcts or transient ischemic attacks that may go unrecognized prior to diagnosis.¹ 

Livedo racemosa often presents years prior to cerebrovascular involvement; however, a case report of Sneddon syndrome without livedo racemosa does exist.^1,2 Sneddon syndrome is estimated to occur in four in 1 million patients, generally women, with an onset between 20 and 42 years of age.² Sneddon syndrome may present with or without antiphospholipid antibodies.^3,4 

Given the presentation and complications associated with this syndrome, multiple subspecialties are often necessary to establish a diagnosis, including neurologists, dermatologists, hematologists and rheumatologists.¹ In this patient’s case, multidisciplinary care coordination was vital, and a team-based approach led to the recognition of her constellation of symptoms as possible Sneddon syndrome, prompting a repeat biopsy. 

This case further highlights that larger biopsies may be necessary to demonstrate histologic evidence of livedo racemosa, which may help establish the diagnosis of Sneddon syndrome.⁴ 

In patients presenting with livedo racemosa, Sneddon syndrome should be included in the differential diagnosis, especially due to the high impact of potential disease complications.

It also is important to keep in mind that a large number of disease processes can be associated with livedo racemosa, including systemic lupus erythematosus, anti­phospholipid antibody syndrome, polyarteritis nodosa and cryoglobulinemic vasculitis, among others. These other diagnoses must be ruled out by further evaluation, including clinical and laboratory testing, prior to a diagnosis of Sneddon syndrome. 

Overall, more evidence is needed to support specific therapy recommendations in patients with Sneddon syndrome. Hydroxychloroquine has previously been reported to have theoretical benefit in patients with Sneddon syndrome due to its anti-thrombotic properties and ability to prevent endothelial dysfunction.¹ 

There is a paucity of data to support the use of anticoagulation over anti­platelet therapy in patients with Sneddon syndrome who lack antiphospholipid antibodies. The decision on which therapy to use should be made on a case-by-case basis. 

Further, given that patients most likely to be affected by Sneddon syndrome are women of childbearing age, the use of anticoagulants, such as warfarin, may be challenging. Warfarin is contraindicated in pregnancy due to its teratogenic potential and ability to induce spontaneous abortion, fetal hemorrhage and fetal death.⁶ Emphasis on effective contra­ceptive methods in patients treated with warfarin is vital. In patients who wish to start a family, careful consideration of the risks associated with temporary discon­tinuation of warfarin or use of low molecular-weight heparin is warranted.