A Retrospective Cohort Study of Subacute Cutaneous Lupus Patients With and Without Systemic Lupus

Abstract

OBJECTIVE: To compare subacute cutaneous lupus erythematosus (SCLE) patients with systemic lupus erythematosus (SLE) (+SCLE/+SLE) versus SCLE patients without SLE (+SCLE/-SLE) over a period of five years. DESIGN: Retrospective cohort study. SETTING: Outpatient dermatology and rheumatology clinics at an academic medical center. PATIENTS: Forty-seven SCLE patients presenting between February 1989 and January 2012 were screened with nineteen meeting inclusion/exclusion criteria. PREDICTIVE VARIABLE: Anti-nuclear antibodies (ANA). RESULTS: Of the nineteen patients included, thirteen (68.4%) had SCLE only (+SCLE/-SLE) for the majority of the study period and six (31.6%) had both SCLE and SLE (+SCLE/+SLE). At baseline, +SCLE/+SLE patients were more likely to have a history of discoid lesions, oral ulcers, lupus non-specific findings, and require multiple medications. Over the five year study period, +SCLE/+SLE patients were also more likely to have ANA, immunologic disease (including anti-double-stranded DNA), renal disease, proteinuria, decreased complement, and to complain of arthralgias. Anti-Ro antibodies alone were more common in +SCLE/-SLE patients. CONCLUSIONS: Various cutaneous manifestations of lupus are present early in the course of SCLE, but laboratory values in +SCLE/+SLE become more distinct over time. Thus, the aforementioned variables should be tested for evidence of disease involvement and to ensure adequate treatment among +SCLE/+SLE patients. In contrast, +SCLE/-SLE patients may be tested for the development of anti-Ro antibodies but need not be monitored for the other laboratory abnormalities, given their rarity among patients with SCLE only. Larger prospective studies comparing disease course in SCLE patients with and without SLE are needed to verify these findings.