TABLE 1
Cutaneous lupus erythematosus: Recognizing the subtypes1
| Acute cutaneous lupus erythematosus (ACLE) |
|---|
| Localized: erythematous macules or papules over the bridge of the nose and cheek, with sparing of the nasolabial folds (“butterfly rash”) |
| Generalized: similar erythematous lesions over other photodistributed parts of the body, including the neck, chest, arms, and hands |
| Toxic epidermal necrolysis-like (TEN-like): blistering and epidermal cleavage in photodistributed parts of the body |
| Subacute cutaneous lupus erythematosus (SCLE) |
| Erythematous papulosquamous (psoriasis-like) eruptions or annular (ring-like) lesions with raised red borders and central clearing, occurring symmetrically and suddenly after sunlight exposure on photo-distributed body parts; the scalp and face are rarely affected |
| Chronic cutaneous lupus erythematosus (CCLE) |
| Discoid lupus erythematosus: erythematous papules and plaques with associated scale, spreading centrifugally with follicular plugging, pigment change, telangiectasia, and atrophy; scarring alopecia can occur |
| Lupus erythematosus profundus: tender, erythematous nodules and plaques, usually involving the proximal extremities, trunk, breasts, buttocks, and face |
| Chilblain lupus erythematosus: tender, erythematous nodules and plaques, occurring in acral areas often in response to cold |
| Intermittent cutaneous lupus erythematosus (ICLE) |
| Lupus erythematosus tumidus: succulent, erythematous, and edematous plaques found on photodistributed parts of the body |
Cutaneous LE diagnosis and treatment: Start with ACR criteria
When evaluating patients with suspected cutaneous LE, it is important not only to identify the subtype, but also to rule out systemic disease using criteria established by the American College of Rheumatology (ACR).17 Notably, 4 of the 11 diagnostic criteria for systemic disease involve visual clues, including malar rash, discoid rash, photosensitivity, and oral ulcerations. Laboratory evidence of systemic disease may include a positive antinuclear antibody, anti-dsDNA, or anti-Sm autoantibody test results, as well as hematologic abnormalities described in the ACR guidelines.
Ultimately, a diagnosis of cutaneous LE should be based on the patient’s history and physical exam, autoantibody profile, and histologic and immunofluorescent biopsy findings. A rheumatologic evaluation may help to determine which patients have systemic disease, as the ACR criteria may overdiagnose systemic LE in those with predominantly skin changes.6
Treatment of cutaneous LE is based on the subtype and extent of disease, with potent topical corticosteroids, in combination with antimalarial agents, being the primary therapies. ACLE skin lesions generally respond best to systemic corticosteroids and immunosuppressive agents (such as azathioprine or cyclophosphamide) that are used to control underlying systemic disease. SCLE can be managed with topical corticosteroids; however, patients typically also require systemic treatment, often with hydroxychloroquine, for optimal control. DLE, the most common form of CCLE, is managed in a similar fashion, with a greater role for intralesional corticosteroid injections. Lesions associated with ICLE, which often resolve spontaneously, may be treated with topical corticosteroids and antimalarials.16 It is also important to advise all patients with cutaneous LE to use a broad-spectrum sunscreen, as ultraviolet (UV) exposure can induce or exacerbate the lesions.9
Dermatomyositis: Rare but serious
Dermatomyositis is an idiopathic inflammatory myopathy characterized by chronic muscle inflammation, symmetric proximal muscle weakness, and distinct cutaneous findings. In addition to possible cardiac and pulmonary complications, dysphagia, and joint contractures, dermatomyositis is associated with cancer, with up to 25% of affected adults having an underlying occult malignancy.18
Dermatomyositis is a rare condition, with a prevalence of only 1 to 10 cases per million adults and 3.2 cases per million children.19 It has a bimodal age distribution, with most juvenile cases affecting children between the ages of 5 and 14 years and most adult cases developing in the fifth and sixth decades of life. Women are affected twice as often as men.18
Suspect dermatomyositis when you see any of the following signs:
- A heliotrope rash: violaceous macules and patches, with or without edema, symmetrically on the periorbital skin, present early in the disease course in 30% to 60% of patients.19 (See image)
- Gottron’s papules: violaceous papules on the dorsal interphalangeal and metacarpophalangeal joints of the hands, elbows, and knees, occurring in as many as 70% of patients (FIGURE 2).19,20
- Gottron’s sign: nonscaling, violaceous erythematous macules and plaques occurring symmetrically in the same distribution as Gottron’s papules, but with sparing of the interphalangeal spaces.20
- Periungual erythema and telangiectasias: redness and dilation of the blood vessels in the skin surrounding the nail plate.
- The shawl and V-signs: erythematous macular eruptions occurring in a “shawl” pattern on the shoulders, arms, and upper back and in a V-shaped pattern on the anterior neck and chest.
- Mechanic’s hand: extensive scaling, fissuring, and roughening of the palmar aspect of the hand.20,21
- Poikiloderma vasculare atrophicans: circumscribed violaceous erythema with thinning of the skin, prominent telangiectasias, and a mottled pattern of hypo- and hyperpigmentation, typically occurring on the anterior neck, chest, posterior shoulders, back, and buttocks, years after onset of the disease.21-24
- Cutaneous calcification (calcinosis cutis): usually on the buttocks, elbows, knees, and traumatized areas, affecting 30% to 70% of children with dermatomyositis, but only 10% of adults with the disorder.20,25-27
FIGURE 2
Gottron’s papules in dermatomyositis
Violaceous papules on the dorsal interphalangeal and metacarpophalangeal joints of the hands are a common manifestation of dermatomyositis.