Lichen planus associated with etanercept

A rare case report of apixaban-induced lichenoid eruption

With recent increase in the use of direct oral anticoagulants (DOACs), several new cases of adverse drug reactions (ADRs) have been identified in pharmacovigilance surveys. These ADRs can result in significant mortality and morbidity if not identified and treated promptly. It is important for physicians to recognize that immunologically mediated delayed hypersensitivity reactions, although rare in occurrence, can have significant impact on patient's quality of life. To the best of our knowledge, we report the first case of lichenoid eruption associated with apixaban. We further provide evidence of tolerance to rivaroxaban in the same patient.

PLAIN LANGUAGE SUMMARY

Apixaban-induced lichenoid eruption Well documented case reports, although providing evidence of probable causal relationship between a drug and specific adverse drug reactions (ADRs), can increase awareness amongst clinicians treating patients with direct oral anticoagulants (DOACs), especially with its rapid utilization. Rare ADRs are difficult to detect as clinical trials of DOACs lacked enough patient sample, making post-marketing reporting of such events important so both patients and clinicians can be vigilant to help with prompt recognition of such symptoms. We report the first case of lichenoid eruption hypersensitivity reaction associated with apixaban in patient with tolerance to rivaroxaban.

Tnfa signaling through tnfr2 protects skin against oxidative stress-induced inflammation

A new zebrafish model of skin inflammatory disease explains new-onset and worsening psoriasis and lichen planus in patients receiving anti-TNFα therapy.

TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of dual oxidase 1 (Duox1)-derived H₂O₂ by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H₂O₂ upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.

Psoriasis and lichen planus are chronic, debilitating skin diseases that affect millions of people worldwide. TNFα is a multifunctional cytokine that mediates acute and chronic inflammation. While TNFα antagonist therapy is used for autoimmune or chronic inflammatory diseases, such as inflammatory bowel disease (IBD), numerous studies have reported new-onset psoriasis and lichen planus following such therapy. We have used the unique advantages of the zebrafish embryo to identify a novel phenotype that mirrors this unexplained and paradoxical onset of psoriasis and lichen planus. We found that depletion of Tnfa or its receptor Tnfr2 caused skin inflammation and hyperproliferation of keratinocytes through the activation of a Duox1/H₂O₂/NF-κB positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients, and pharmacological inhibition of Duox1 abrogated skin inflammation, placing Duox1-derived H₂O₂ upstream of this inflammatory loop. Our results suggest that therapies targeting DUOX1 and H₂O₂ could provide innovative approaches to the management of skin inflammatory disorders.

Nail Lichen Planus: Successful Treatment with Etanercept

Background

Etanercept is a fully human tumor necrosis factor a receptor fusion protein that binds tumor necrosis factor a with greater affinity than natural receptors. Biologics are widely used in the treatment of psoriasis and psoriasis arthritis and may represent a new therapeutic option for some patients with psoriatic nail disease.

Case Report

We report a case of lichen planus limited to the toe nails successfully treated with etanercept monotherapy.

Conclusion

The significant improvement of our case suggests that etanercept is an effective treatment modality for lichen planus limited particularly to the nails. Further controlled studies are needed to establish the effectiveness and therapeutic regimes.