Interferon-alpha may be used as biomarker for cutaneous lupus erythematosus, flares

Key takeaways:

• 38% of patients with cutaneous lupus erythematosus displayed evidence of positive interferon (IFN)-alpha activity.
• IFN-alpha activity was 3.11 times more likely to be present in patients with active disease.

Interferon-alpha activity may be used routinely in clinical settings as a biomarker for cutaneous lupus erythematosus and disease flares, according to a study.

“[Cutaneous lupus erythematosus (CLE)], with or without associated systemic lupus erythematosus, is a chronic disease characterized by unpredictable flares which can lead to severe and permanent dyspigmentation and/or scarring,” Quitterie Murat de Montai, MD, of Sorbonne University and the Tenon Hospital of the Assistance Publique Hospital of France, colleagues wrote. “Preventing and anticipating these flares is a significant clinical challenge and an important unmet need in CLE.”

Currently, there is no biomarker routinely available of CLE activity and risk for flare. However, interferon (IFN)-alpha signaling plays a central role in the pathogenesis of systemic lupus erythematous (SLE) and may present as a biomarker of CLE. To evaluate this theory, the researchers conducted a cohort study.

Out of 184 patients with CLE with (53%) or without (47%) systemic lupus erythematosus, 38% displayed evidence of positive IFN-alpha activity.

IFN-alpha activity was 3.11 (95% CI, 1.61-6.01) times more likely to be present in patients with active CLE. IFN-alpha activity was linked to moderate to severe CLE activity (OR = 4.43; 95% CI, 1.99-9.86) and associated SLE (OR= 2.17; 95% CI, 1.19-4).

Those with inactive CLE (n = 65) that had positive IFN-alpha activity faced a 4.95 (95% CI, 1.12-21.78) times greater risk for a CLE flare at 6 months vs. those with undetectable IFN-alpha activity.

In contrast, C3 serum levels (HR = 0.58; 95% CI, 0.16-2.12) and positive anti-dsDNA abs (HR = 2.53; 95% CI, 0.67-9.61) were not associated with a significant risk for flare, firming the belief that IFN-alpha activity may be a reliable biomarker for CLE flares.

IFN-alpha activity not being universally available was considered a limitation, according to the authors.

“Given the heterogeneous nature of CLE, identifying a biomarker capable of simultaneously assessing activity, severity, prognosis and treatment response is challenging,” Murat de Montai and colleagues wrote. “These results suggest that serum IFN-alpha activity is an interesting biomarker of CLE activity that may be more widely available.”