PRACTICE RECOMMENDATIONS
• When evaluating patients with suspected cutaneous lupus erythematosus, use multiple criteria—including histologic and immunofluorescent biopsy findings and American College of Rheumatology criteria—to rule out systemic disease. C
• Cancer screening with a careful history and physical examination is recommended for all adult patients whom you suspect of having dermatomyositis. C
• Suspect mixed connective tissue disease in patients with skin findings characteristic of varying auto-immune disorders appearing sequentially over several months or years. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
Many systemic conditions are accompanied by skin manifestations. This is especially true for connective tissue disorders, for which dermatologic findings are often the key to diagnosis.
In this review, we describe the dermatologic findings of some well-known connective tissue disorders. The text and photographs in the pages that follow will help you hone your diagnostic skills, leading to earlier treatment and, possibly, better outcomes.
Lupus erythematosus: Cutaneous and systemic disease often overlap
Lupus erythematosus (LE), a chronic, inflammatory autoimmune condition that primarily affects women in their 20s and 30s, may initially present as a systemic disease or in a purely cutaneous form. However, most patients with systemic LE have some skin manifestations, and those with cutaneous LE often have—or subsequently develop—systemic involvement.1 Thus, recognizing the cutaneous manifestations of LE will not only aid in diagnosis, but will help you identify patients at risk for systemic disease.
Cutaneous LE has 4 subtypes
There are 4 subcategories of cutaneous LE—acute, subacute, chronic, and intermittent.2 Each is differentiated by the appearance of the lesions (TABLE 1), histology, and serological markers.1 Photosensitivity is common to all the subcategories to varying degrees.
Acute cutaneous lupus erythematosus (ACLE) is typically characterized by the classic malar “butterfly” rash, an erythematous eruption of macules or edematous papules over the bridge of the nose and cheek.3 Although this presentation is most common, there are variations—1 in which the lesions cover other exposed areas (commonly including the “V” of the chest, the extensor surface of the arms, and the hands), and a rare form in which toxic epidermal necrolysis-like blistering occurs.1,4 These skin changes—which generally last anywhere from a few hours to several weeks—typically resolve without scarring, although pigment changes can occur.5
Left: Dermatomyositis is the underlying cause of the heliotrope discoloration on this patient’s upper eyelid.
Center: Linear morphea is associated with the lesion on this patient’s face—called en coup de sabre because it resembles the mark caused by the stroke of a sword in a duel.
Right: Discoid lupus erythematosus causes hypopigmentation and scarring.Patients with ACLE have a predisposition to systemic LE; unlike those with other forms of cutaneous LE, 40% to 90% will have double-stranded DNA (dsDNA) autoantibodies.3,6
Subacute cutaneous lupus erythematosus (SCLE), which usually affects middle-aged Caucasian women, is characterized by erythematous papulosquamous (psoriasis-like) eruptions or annular lesions with raised red borders and central clearing—or both. These lesions, which are nonscarring, lack in-duration, and rarely affect the scalp or face, appear suddenly, usually after exposure to sunlight (FIGURE 1)5,7-9 or certain drugs. Hydrochlorothiazide, terbinafine, calcium channel blockers, and angiotensin-converting enzyme inhibitors are common offenders.1,6
FIGURE 1
Annular lesions in subacute cutaneous lupus erythematosus
Ring-like lesions with raised red borders and central clearing on the back of a patient with subacute cutaneous lupus erythematosus.
SCLE is often associated with extracutaneous symptoms such as arthritis and myalgias,1,8 but patients are at relatively low risk for severe systemic manifestations.5,8,10 Serology is often notable, with anti-Ro (SS-A) antibodies present in 70% to 90% of patients and anti-La (SS-B) autoantibodies found in 30% to 50%.1,11
Chronic cutaneous lupus erythematosus (CCLE) also occurs predominantly in females, at a ratio as high as 5 to 1.12 There are 3 variations of CCLE: discoid lupus erythematosus (DLE), LE profundus, and chilblain LE (TABLE 1). DLE, characterized by alopecia, skin atrophy, and dyspigmentation, is the most common and affects patients of all ages and ethnic groups.9,13,14 (See image above.)
DLE lesions typically begin as erythematous papules and plaques with scale. As the disorder progresses, the lesions spread, causing follicular plugging, peripheral hyperpigmentation and central hypopigmentation, telangiectasia, and atrophy.9,15 In some cases, patients develop thickened, scarred skin and permanent scarring alopecia.15 Prompt recognition of DLE is particularly important, as early referral and treatment may reduce the likelihood of permanent scarring alopecia and pigment changes.11
Intermittent cutaneous lupus erythematosus (ICLE), a relatively new subtype of cutaneous LE, is represented by a rare condition—lupus erythematosus tumidus (LET)—reported in <100 cases worldwide. LET is characterized by succulent, erythematous, and edematous plaques on sun-exposed parts of the body.1,16