Subacute Cutaneous and Systemic Lupus Erythematosus

Abstract

Lupus erythematosus is a multi-organ autoimmune disease which presumably results from a complex interplay of genetic and environmental factors. The clinical phenotype of LE ranges in continuum from minor cutaneous lesions to life-threatening vital multi organ dysfunction. Throughout this continuum, skin manifestations are variable and common. There is a commonly accepted classification system that divides lesions into LE specific and LE non-specific cutaneous disease. LE specific cutaneous disease includes three clinically, immunologically and genetically distinct disorders: acute cutaneous LE (ACLE), subacute cutaneous LE (SCLE) and chronic cutaneous LE (CCLE). Histopathological differentiation between especially the first two disorders can be difficult. SCLE is clinically characterized by non-scarring, non-indurated, erythematous, papulo-squamous and/or annular skin lesions occurring in a symmetric, photo distributed pattern. Patients with SCLE tend to exhibit milder systemic symptoms than those with unselected systemic LE (SLE). Although not mandatory for diagnosis, the majority of SCLE patients produce anti-Ro / SSA autoantibodies. In SLE, musculoskeletal symptoms such as arthritis and arthralgias are the most common systemic manifestations observed. Overall, most patients with SCLE tend to have mild systemic disease and it appears that isolated joint symptoms are a marker for milder disease. The clinical diagnosis of SCLE is not always obvious. Annular lesions can be confused with erythema annulare centrifugum, granuloma annulare, erythema gyratum repens, tinea corporis or erythema multiforme. Lesional photodistribution, characteristic histopathology and Ro/SS-A autoantibodies are useful in distinguishing SCLE from its differential diagnosis. Most SCLE patients tend to have intermittent recurrent skin lesions without significant disease progression, while some may experience permanent remissions. Approximately 15 percent of patients develop active SLE. The most common complaints other than skin lesions and photosensitivity were fatigue, arthralgias and Raynaud’s phenomenon. In addition, many patients had a subjective history of depression.The real prognosis of SCLE needs to be evaluated in a larger number of patients to more firmly establish its course, ANA and Ro/SS-A prevalence, overlap with other connective tissue diseases, as well as prognosis.