Lichen Planus Pemphigoides Mimicking Toxic Epidermal Necrolysis

Lichen Planus: What is New in Diagnosis and Treatment?

Lichen planus (LP), an idiopathic, multifaceted chronic inflammatory disease with a heterogeneous clinical presentation, affects approximately 0.5-1% of the population. The various clinical manifestations of LP fall into three broad categories, namely cutaneous, appendageal, and mucosal, with further subclassification depending on the morphology and distribution patterns of individual lesions. There is mounting evidence that LP has systemic associations, including autoimmune conditions, glucose intolerance, dyslipidemia, and cardiovascular disorders. Cutaneous hypertrophic and mucosal forms of LP are at a heightened risk for malignant transformation. Familiarity with these potential associations in conjunction with long-term follow-up and regular screening could lead to a timely diagnosis and management of concomitant conditions. In addition, the frequent quality of life (QoL) impairment in LP underscores the need for a comprehensive approach including psychological evaluation and support. Several treatment strategies have been attempted, though most of them have not been adopted in clinical practice because of suboptimal benefit-to-risk ratios or lack of evidence. More recent studies toward pathogenesis-driven treatments have identified Janus kinase inhibitors such as tofacitinib, phosphodiesterase-4 inhibitors such as apremilast, and biologics targeting the interleukin-23/interleukin-17 pathway as novel therapeutic options, resulting in a dramatic change of the treatment landscape of LP. This contemporary review focuses on the diagnosis and management of LP, and places emphasis on more recently described targeted treatment options.

Lichenoid dermatitis following PD-1 inhibitor-induced toxic epidermal necrolysis: a case report and literature review

Immune checkpoint inhibitors such as anti-PD-1 receptor antibodies have been shown to be effective in patients with advanced gastric cancer. However, there is a growing concern about immune-related adverse events. A case of a patient with gastric adenocarcinoma who developed toxic epidermal necrolysis (TEN) induced by sintilimab and subsequently developed lichenoid dermatitis is reported. TEN was diagnosed according to a history of sintilimab use, clinical symptoms and physical examination. During hospitalization, the patient developed recurrent fever caused by bacteremia and recovered from TEN after anti-infection and anti-inflammatory treatments. However, when TEN was controlled, the patient developed the lesional manifestations of lichenoid dermatitis. To date, no cases of lichenoid dermatitis after TEN have been reported following the use of PD-1 inhibitors.

TEN mimics: Classification and practical approach to toxic epidermal necrolysis-like dermatoses

Toxic epidermal necrolysis (TEN) is an acute life-threatening dermatologic emergency. However, many dermatoses can present with a TEN-like eruption. Those "TEN-mimics" are a true diagnostic challenge and an alarming differential diagnosis to such a serious condition. Herein, we will expose and classify the landscape of TEN-mimics. Also, the key differentiating clinical and/or laboratory points will be highlighted to help an accurate diagnosis of either a TEN or a TEN-like presentation.