Etanercept-induced lupus in a patient with rheumatoid arthritis: case report

Abstract

Tumor necrosis factor (TNFα) inhibitors, such as etanercept, are essential in the management of rheumatoid arthritis (RA). Despite their efficacy, paradoxical adverse effects, such as the development of lupus-like syndromes, have been reported. The clinical and serological presentation of etanercept-induced lupus (EIL) may differ from individual to individual and may present atypical findings compared to other lupusinducing drugs. A 54-year-old female patient with RA was evaluated. After starting etanercept, she began to present skin lesions: initially an erythematous papule on the dorsal aspect of the foot that evolved into an ulcer that progressively spread asymmetrically to the extremities. A bilateral malar rash, polymorphic skin changes, non-scarring alopecia, and aphthous ulcers on the oral mucosa were evident. Positive antinuclear antibodies (ANA) with cytoplasmic and nuclear patterns were present, as was positive anti-RNP antibody, along with other markers consistent with RA, while anti-dsDNA and anti-histone antibodies were negative. The clinical picture resolved after discontinuing anti-TNFα treatment. In SIL, the presence of ANA is common; however, antidsDNA is usually negative. It often shares clinical features with SLE, but the rapid improvement ofsymptoms after discontinuing etanercept reinforces the causal relationship with SIL. Despite the increasing use of anti-TNFα therapies in RA, the lack of detailed case reports of SIL underscores the importance of communicating relevant clinical observations associated with the administration of this drug.