Conference Coverage

Skin signs spotlight highest-risk SLE patients


 

EXPERT ANALYSIS FROM THE EADV CONGRESS

– Careful skin examination in patients known to have systemic lupus erythematosus (SLE) can reveal subtle findings indicative of systemic thrombotic vasculopathy warranting prompt initiation of long-term antiplatelet therapy, Dan Lipsker, MD, PhD, said in a plenary lecture at the annual congress of the European Academy of Dermatology and Venereology.

“Those patients are at very high risk. Those are the lupus patients with the poorest prognosis. Those are the lupus patients who still die today,” said Dr. Lipsker, professor of dermatology at the University of Strasbourg (France).

Dr. Dan Lipsker

Dr. Dan Lipsker

He cited a classic observational study by the European Working Party on Systemic Lupus Erythematosus in which 1,000 SLE patients in seven European countries were prospectively followed for 10 years. During the first 5 years, the most common causes of death were infections and active, progressive, unstoppable SLE. In the second 5 years, however, thrombotic events – stroke, acute MI, pulmonary embolism – moved to the fore and became the most common causes of mortality (Medicine. 2003 Sep;82[5]:299-308).

Cutaneous clues suggestive of thrombosis in SLE patients include atrophie blanche, pseudo-Degos lesions, livedo racemosa, acral nonpalpable purpura or reticulate erythema, cutaneous necrosis, splinter hemorrhage, thrombophlebitis, and nailfold telangiectasias. These skin findings can occur simultaneously with or after potentially life-threatening thrombotic events, or in the best of all scenarios, beforehand.

Dr. Lipsker told his audience of dermatologists that, by demonstrating facility in identifying these cutaneous disorders, they can make themselves “indispensable” to the rheumatologists, nephrologists, internists, and/or pediatricians who often provide the bulk of specialized care for SLE patients.

Courtesy RegionalDerm.com

Atrophie blanche

Nondermatologists typically lack experience with these telltale skin lesions, and they cannot interpret a skin biopsy. Moreover, their practice guidelines often fail to recognize the diagnostic, therapeutic, and prognostic value of searching for these skin findings. For example, recent British Society for Rheumatology guidelines on the management of SLE go into extensive detail on the importance of regular laboratory monitoring of hematologic, renal, and biochemical parameters – every 3 months in patients who are clinically quiet but serologically active, and every 6 months in those with inactive disease and no previous organ damage – but the guidelines make no mention of the skin clues to thrombotic vasculopathy (Rheumatology. 2018 Jan 1;57[1]:e1-45. doi: 10.1093/rheumatology/kex286).

“We know today that, 5 years after initial diagnosis of SLE, the chief causes of morbidity and mortality are thrombotic events. And it can be extremely difficult to distinguish between an acute autoimmune lupus flare and a thrombotic event when, for example, the CNS or eyes are involved. But you will find direct evidence of thrombosis by carefully examining the skin,” the dermatologist maintained.

Some of these cutaneous signs constitute unequivocal evidence of thrombosis in SLE patients. Others are more ambiguous but should raise suspicion of an ongoing systemic thrombotic process unless another explanation is found.

One example of a skin finding that always indicates thrombosis is pseudo-Degos lesions: ivory-colored or white depressed atrophic papules with a raised border composed of telangiectasias. Biopsy shows evidence of a cone-shaped dermal arteriolar infarct.

Courtesy RegionalDerm.com

Livedo racemosa in a patient with SLE, showing the irregular, net-like mottling surrounding pale skin.

Another cutaneous finding that constitutes indisputable evidence of a thrombotic vasculopathy is acral noninfiltrated stellar purpura.

“We have biopsied dozens of patients with this presentation, and you always find occluded vessels without a single inflammatory cell. These lesions are usually painful, and when you put those patients on low-dose aspirin they do better,” Dr. Lipsker said.

Atrophie blanche in a patient with SLE is also strong evidence of thrombotic vasculopathy. Atrophie blanche is a porcelain-white atrophic white scar with surrounding hyperpigmentation on the lower leg that occurs after skin injury in an area with venous insufficiency.

Livedo racemosa in a patient with SLE is also highly suggestive of a systemic thrombotic process. Characteristic of this dermatologic disorder is an irregular, netlike mottling surrounding pale skin.

“All of these skin signs allow identification of patients who have very high risk of thrombotic events,” Dr. Lipsker stressed.

He reported having no financial conflicts of interest regarding his presentation.

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