Role of biomarkers in the diagnosis and prognosis of patients with cutaneous lupus erythematosus

Abstract

Cutaneous lupus erythematosus (CLE) is a connective tissue disease with varying presentations, and clinical sequelae including itching, dyspigmentation, and scarring. CLE can occur as its own entity or in conjunction with systemic disease, known as systemic lupus erythematosus (SLE). Because CLE is clinically diverse, identification of a biomarker may help not only facilitate early diagnosis and management but also identify individuals at risk for poor prognosis and development of SLE. While potential biomarkers in SLE have been extensively studied, few biomarkers for CLE have been identified and incorporated into clinical practice. Anti-SS-A antibody is a commonly used biomarker for diagnosis of subacute CLE patients. Type I interferon-related proteins such as MxA and guanylate binding protein-1 (GBP-1) and chemokines such as CXCR3, CXCL9, and CXCL10 have been identified as biomarkers that may support diagnosis and track disease activity. First-line oral treatment for CLE currently consists of anti-malarials such as hydroxychloroquine (HCQ), chloroquine (CQ), and quinacrine (QC). Studies have found that an increased myeloid dendritic cell population with higher TNF-α expression may be predictive of poor treatment response to HCQ in CLE patients. Autoantibodies against nuclear antigens (e.g., anti-double-stranded DNA and anti-Smith antibodies) and elevated erythrocyte sedimentation rate have been more commonly found in CLE patients progressing to SLE than those who have not. This review aims to summarize previous and emerging biomarkers for CLE patients.

Keywords: Biomarkers; cutaneous lupus erythematosus (CLE); systemic lupus erythematosus.

Figure 1

Biomarkers associated with systemic involvement in patients with CLE. Laboratory tests associated with SLE development from studies comparing SLE patients with CLE and CLE-only patients (A), and those comparing CLE patients who develop SLE and DLE-only patients (B). Signs commonly identified from both types of studies are listed in the Venn diagram overlap. Ab, antibody; ANA, antinuclear antibody; BAFF, B-cell activating factor; CH50, total hemolytic complement; dsDNA, double-stranded DNA; ESR, erythrocyte sedimentation rate; RNP, ribonucleotide protein; CLE, cutaneous lupus erythematosus; SLE, systemic lupus erythematosus. Adapted from Chong et al. 2011 (46).