Cutaneous Manifestations
Andrea Kalus, MD, associate professor of dermatology at the University of Washington, Seattle, began her talk by reviewing the cutaneous manifestations of lupus. She explained that skin involvement occurs in the majority (72–85%) of SLE patients and is the first sign of disease in around a quarter of SLE patients. Most patients with cutaneous lupus erythematosus (CLE) are young women, but the disease can occur in both sexes at any age. In all cases, ultraviolet light is a dependable and controllable trigger for skin symptoms.
Dr. Kalus manages CLE by first encouraging all patients to reduce sun exposure and stop smoking. She will treat patients who have limited disease with topical steroids, intralesional steroids, topical calcineurn inhibitors and hydroxychloroquine. In contrast, for patients with extensive disease, she prescribes methotrexate and/or mycophenolate, and low-dose steroids when needed. If the patient has refractory disease, she turns to lenalidomide or thalidomide, belimumab and/or retinoids.
The type of CLE also informs the treatment decision. Lupus can present in the skin in several ways, all of which have distinct clinical features and are associated with different risks of systemic disease. Chronic CLE includes discoid lupus erythematosus, lupus panniculitis and tumid lupus. Subacute CLE presents with rings and semicircles on the upper body, while the face is typically bare. The final subtype is acute CLE, which is present in 40–50% of patients at the diagnosis of acute systemic lupus. Although histology can help diagnose lupus, it does not differentiate between the subtypes of cutaneous lupus. Instead, diagnosis relies on the combination of clinical, histologic and laboratory features.
Discoid lupus presents with red papules, primarily on the head and neck, which gradually expand into a plaque and then scar. The scars can be disfiguring, with scarring alopecia. Dr. Kalus notes the conchal bowl of the ear of patients with discoid lupus often contains scarring alopecia. Discoid lupus is the most frequent skin manifestation of lupus and, although high potency topical steroids aren’t often used on facial skin, they are the appropriate treatment for this condition. Other options to prevent scarring include intralesional steroids and hydroxychloroquine, which can help prevent future lesions.
Subacute CLE presents as erythematous polycyclic or ring-shaped macules and papules with some scale that are predominantly located on the upper chest and back. Patients, especially those with more skin pigment, tend to have hyperpigmentation as they heal. It can take six months to a year for the hyperpigmentation to clear. Patients also have marked photosensitivity, and approximately 70% have anti-Sjögren’s-syndrome-related antigen A (anti-SSA/anti-Ro) antibodies and, thus, may meet the criteria for SLE. Patients with subacute CLE typically have a benign clinical course and, although pigment changes may occur, there is no scarring.
Dr. Kalus suggested the first thing a physician should do when presented with a patient newly diagnosed with subacute CLE is to review the medication list. Approximately 40 different medications have been reported to cause subacute CLE. These include hydrochlorothiazide, calcium channel blockers, angiotensin-converting enzyme inhibitors and terbinafine. If a patient is taking any of these drugs, the drugs should be discontinued and the subacute CLE may resolve without any treatment.
Acute CLE presents as a malar erythema that can also be more generalized rash on the forehead, chest and body. The rashes worsen with sun exposure and systemic disease flares. Dr. Kalus encourages patients to reduce sun exposure and encourages vitamin D supplementation at a minimum of 400 international units daily. Dr. Kalus also emphasized that although tumid lupus has historically been classified as a form of cutaneous lupus and is very photosensitive, it’s never associated with systemic lupus and, therefore, does not need to be considered a form of cutaneous lupus.