Lichen Planus Pemphigoides: From Lichenoid Inflammation to Autoantibody-Mediated Blistering

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.

State-of-the-art diagnosis of autoimmune blistering diseases

Autoimmune blistering disorders (AIBDs) are a heterogeneous group of approximately a dozen entities comprising pemphigus and pemphigoid disorders and dermatitis herpetiformis. The exact diagnosis of AIBDs is critical for both prognosis and treatment and is based on the clinical appearance combined with the detection of tissue-bound and circulating autoantibodies. While blisters and erosions on the skin and/or inspectable mucosal surfaces are typical, lesions may be highly variable with erythematous, urticarial, prurigo-like, or eczematous manifestations. While direct immunofluorescence microscopy (IFM) of a perilesional biopsy is still the diagnostic gold standard, the molecular identification of the major target antigens opened novel therapeutic avenues. At present, most AIBDs can be diagnosed by the detection of autoantigen-specific serum antibodies by enzyme-linked immunosorbent assay (ELISA) or indirect IFM when the clinical picture is known. This is achieved by easily available and highly specific and sensitive assays employing recombinant immunodominant fragments of the major target antigens, i.e., desmoglein 1 (for pemphigus foliaceus), desmoglein 3 (for pemphigus vulgaris), envoplakin (for paraneoplastic pemphigus), BP180/type XVII collagen (for bullous pemphigoid, pemphigoid gestationis, and mucous membrane pemphigoid), laminin 332 (for mucous membrane pemphigoid), laminin β4 (for anti-p200 pemphigoid), type VII collagen (for epidermolysis bullosa acquisita and mucous membrane pemphigoid), and transglutaminase 3 (for dermatitis herpetiformis). Indirect IFM on tissue substrates and in-house ELISA and immunoblot tests are required to detect autoantibodies in some AIBD patients including those with linear IgA disease. Here, a straightforward modern approach to diagnosing AIBDs is presented including diagnostic criteria according to national and international guidelines supplemented by long-term in-house expertise.

Lichen planus pemphigoides with predominant mucous membrane involvement: a series of 12 patients and a literature review

Background

Lichen planus pemphigoides (LPP), an association between lichen planus and bullous pemphigoid lesions, is a rare subepithelial autoimmune bullous disease. Mucous membrane involvement has been reported previously; however, it has never been specifically studied.

Methods

We report on 12 cases of LPP with predominant or exclusive mucous membrane involvement. The diagnosis of LPP was based on the presence of lichenoid infiltrates in histology and immune deposits in the basement membrane zone in direct immunofluorescence and/or immunoelectron microscopy. Our systematic review of the literature, performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, highlights the clinical and immunological characteristics of LPP, with or without mucous membrane involvement.

Results

Corticosteroids are the most frequently used treatment, with better outcomes in LPP with skin involvement alone than in that with mucous membrane involvement. Our results suggest that immunomodulators represent an alternative first-line treatment for patients with predominant mucous membrane involvement.

Literature analysis of cutaneous adverse reactions induced by tislelizumab

OBJECTIVE

Tislelizumab may induce immune-related adverse events, especially adverse skin events. Early detection and timely intervention of cutaneous adverse events are crucial to improve patients' quality of life and reduce the disruption of therapeutic regimens. This study aimed to determine the clinical characteristics of cutaneous adverse reactions to tislelizumab and offer a reference for its rational clinical use.

METHODS

Case reports of cutaneous adverse reactions induced by tislelizumab were collected from the relevant databases (up to 31 March 2023). Patient age, sex, primary disease, medication use, occurrence of adverse skin conditions, treatment, and outcomes were recorded and descriptively analysed.

RESULTS

A total of 13 patients were enrolled, including six males and seven females, aged 55-79 years, with a median age of 75 years and a mean age of 70.92 ± 8.84 years. The original disease was lung carcinoma in none patients, cervical carcinoma in two, and urothelial carcinoma and squamous cell carcinoma in one each. The time from the initiation of medication use to the occurrence of cutaneous adverse reactions ranged from 7 to 177 days. Among the 13 patients, 10 showed improvement after drug withdrawal or symptomatic treatment. Two patients died (one died of disease progression and multiorgan failure, one died of acute coronary syndrome), and one patient's adverse skin reactions persisted without treatment.

CONCLUSIONS

Tislelizumab-related cutaneous adverse reactions mostly occur after several days to months of treatment. In clinical practice, evaluation and monitoring should be strengthened. More attention should be paid to erythema and rashes, which may be signs of serious adverse skin reactions. Early detection and intervention can ensure the safe use of drugs and provide greater clinical benefits to patients.

Lichen planus pemphigoides induced by anti-PD-1 antibody: A case only involved in oral mucosa with excellent topical treatment efficiency

Lichen planus pemphigoides (LPP) is a rare autoimmune subepidermal disease that can occur in patients receiving immune checkpoint inhibitors. Its clinical manifestations are combined with the characteristics of lichen planus with bullous pemphigoid that can occur on either skin or oral mucosa. It should be noted that oral LPP is very rare. Here, we report a novel case of oral LPP induced by an anti-PD-1 agent. The patient presented with typical clinical features in oral mucosa, and the diagnosis was based on histopathology and immunological studies. Given that the patient was receiving an anti-PD-1 agent, topical therapy was chosen, and a nice therapeutic effect was obtained. No significant recurrence was observed after a 2-year follow-up. A good and stable therapeutic effect achieved by rapid and local symptomatic medication suggests that accurate and sensitive diagnosis is necessary.

Oral Lichen Planus: An Update on Diagnosis and Management

Oral lichen planus (OLP) is a chronic inflammatory disease whose pathogenesis involves a T-cell mediated, epithelium-directed inflammation in response to unknown antigen(s). The disease evolves by intermittent flares and displays polymorphous clinical features (reticular, erosive, atrophic, plaque, papular, bullous, etc.). When present, symptoms vary depending on the clinical form and range from discomfort to severe pain. Topical superpotent corticosteroids constitute the first-line treatment of symptomatic flares, whereas a wide range of second/third-line treatments are available among topical calcineurin inhibitors, systemic corticosteroids, systemic retinoids, topical/systemic immunomodulators, etc. Follow-up of patients is necessary to detect transformation into squamous cell carcinoma, occurring in approximately 1% of patients.

Involvement of palms and soles in patients with autoimmune bullous diseases: a comparative analysis of a diagnostically relevant localization

Introduction

The involvement of palms and soles is variable among disease entities belonging to autoimmune bullous diseases (AIBD). We present our own clinical-laboratory experience concerning presentations of skin lesions on palms and soles in the pemphigus diseases group, pemphigoid diseases group, epidermolysis bullosa acquisita (EBA), and lichen planus pemphigoides (LPP) and discuss the pertinent literature.

Methods

Lesions on palms and soles were assessed retrospectively on the basis of just photographic archives from the beginning of 2014 to March 2023. We comparatively evaluated 462 Slavic patients with AIBD.

Results

Palmoplantar involvement was observed in only 21 patients with AIBD (12 females and 9 males). There was no statistically significant difference between palmoplantar involvement in the pemphigus diseases group compared to the pemphigoid diseases group and no statistically significant difference between the pemphigus diseases group compared to the subepithelial AIBD.

Discussion

Nevertheless, particularly in LPP and EBA, and occasionally in pemphigus diseases and pemphigoid diseases groups of AIBD, localization on palms and soles may be diagnostically important at the clinical level.

Pemphigus and pemphigoids: Clinical presentation, diagnosis and therapy

Pemphigus and pemphigoid are two potentially life-threatening groups of autoimmune diseases, characterized by autoantibodies targeting structural components of desmosomes or hemidesmosomes, respectively. Affected patients typically show itchy/painful plaques or blistering skin lesions and/or impairing mucosal blistering and erosions, which may strongly impact their quality of life. Since the milestone work of Walter Lever in 1953, who differentiated these two groups of diseases by histopathological analysis of the level of antibody-mediated skin cleavage, enormous progresses occurred. Achievements made in laboratory diagnostics now allow to identify antigen specific structural proteins of the skin that are targeted by pathogenic autoantibodies. These progresses were accompanied by an increased understanding of the pathogenesis of these diseases thanks to the establishment of animal models reproducing disease and on studies on skin and blood of affected individuals, which have been leading to novel and disease-specific treatments. Yet, given their phenotypical overlap with more common dermatological diseases, correct diagnosis and appropriate treatment are often delayed, in some cases leading to irreversible sequelae, including organ dysfunction (i.e., loss of vision in mucous membrane pemphigoid). Here, we provide a concise overview of the clinical appearance, diagnosis and therapeutic management of pemphigus and pemphigoid diseases.

Oral lichen planus and related lesions. What should we accept based on the available evidence?

Recent new terminologies have been proposed for lesions in the sphere of oral lichen planus (OLP) that theoretically present unique aetiological, clinical, prognostic or management characteristics different from those of the so-called typical forms of OLP. We aimed to critically analyse what concepts and terminologies related to OLP should we accept based on the available evidence. A review of the literature was carried out in order to critically analyse the concepts and terminologies related to OLP. New concepts and terminologies include oral lichenoid lesions; contact lichenoid reactions, drug lichenoid reactions or those in the context of graft-versus-host disease; chronic ulcerative stomatitis; lichen planus pemphigoid; and some lesions that are difficult to categorise, such as OLP with features of proliferative verrucous leukoplakia and lichenoid lesions of the upper labial mucosa. A multidisciplinary, multicontinent working group has recently published a guideline with recommendations for modifying definitions and terminologies associated with a disease, among which a reasoned, evidence-based justification for the proposed change is considered essential. An in-depth analysis of the newly proposed terms for OLP-related lesions shows that many of them are not justified. In this paper, we set out our position on the basis of the existing evidence on the appropriateness of the use of these new terms.

Pemphigus- und Pemphigoid-Erkrankungen: Klinik, Diagnostik und Therapie: Pemphigus and pemphigoids: Clinical presentation, diagnosis and therapy

Pemphigus und Pemphigoid sind seltene Autoimmunkrankheiten der Haut mit potenziell lebensbedrohlichem Verlauf. Autoantikörper gegen epidermale und junktionale Strukturproteine (Desmosomen sowie Hemidesmosomen) führen bei Betroffenen typischerweise zu juckenden, schmerzhaften Plaques oder Blasen an der Haut und/oder Blasenbildung und Erosionen der Schleimhäute mit möglicher Einschränkung der Lebensqualität. Seit der bahnbrechenden Arbeit von Walter Lever im Jahr 1953, dem es gelang, mittels histopathologischer Untersuchung diese beiden Krankheitsgruppen anhand des Musters der Antikörper‐vermittelten Blasenbildung zu differenzieren, wurden enorme Fortschritte im Verständnis der Erkrankungen erzielt. Die Errungenschaften in der Labordiagnostik ermöglichten die Identifikation von Zielstrukturen zur präzisen Unterscheidung verschiedener Varianten der bullösen Autoimmunerkrankungen. Diese Fortschritte gingen dank der Entwicklung von Tiermodellen mit einem besseren Verständnis der Pathogenese einher. Außerdem haben Studien an Haut und Blut betroffener Patienten zu neuen und krankheitsspezifischen Behandlungen geführt. Aufgrund ihrer Seltenheit und der klinischen Ähnlichkeit mit anderen dermatologischen Erkrankungen verzögern sich die korrekte Diagnosestellung und die Einleitung einer entsprechenden Therapie häufig, was in einigen Fällen zu irreversiblen Folgeerscheinungen, einschließlich Funktionsstörungen von Organen (zum Beispiel Verlust des Sehvermögens beim Schleimhautpemphigoid) führt. Wir geben hier einen Überblick über das klinische Erscheinungsbild, den Diagnosealgorithmus und das therapeutische Management von Pemphigus‐ und Pemphigoid‐Erkrankungen.

Pembrolizumab-Induced Lichen Planus Pemphigoides in a Patient with Metastatic Adrenocortical Cancer: A Case Report and Literature Review

While the advent of immune-checkpoint inhibitors has revolutionized cancer therapy, immune-related adverse effects (irAEs) have also been on the rise. Cutaneous toxicities are among the most common irAEs, especially in the context of programmed cell death protein-1 (PD-1) inhibitors like pembrolizumab. Herein, we report a case of anti-PD-1-induced lichen planus pemphigoides (LPP)-a rare autoimmune blistering disorder with characteristics of both lichen planus and bullous pemphigoid. To our knowledge, this is the first reported case of LPP following anti-PD-1 therapy for metastatic adrenocortical cancer. Recognizing that LPP is within the spectrum of irAEs is important, especially as the indications for immunotherapy grow to include rarer malignancies like adrenocortical cancer. In addition to our case presentation, we also provide a comprehensive review of the literature surrounding immunotherapy-induced LPP-highlighting key characteristics towards the early recognition and clinical management of this cutaneous irAE.

Autoimmune bullous dermatoses in cancer patients treated by immunotherapy: a literature review and Italian multicentric experience

Cutaneous immune-related adverse events are frequently associated with immune checkpoint inhibitors (ICIs) administration in cancer patients. In fact, these monoclonal antibodies bind the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1/ligand 1 leading to a non-specific activation of the immune system against both tumoral cells and self-antigens. The skin is the most frequently affected organ system appearing involved especially by inflammatory manifestations such as maculopapular, lichenoid, psoriatic, and eczematous eruptions. Although less common, ICI-induced autoimmune blistering diseases have also been reported, with an estimated overall incidence of less than 5%. Bullous pemphigoid-like eruption is the predominant phenotype, while lichen planus pemphigoides, pemphigus vulgaris, and mucous membrane pemphigoid have been described anecdotally. Overall, they have a wide range of clinical presentations and often overlap with each other leading to a delayed diagnosis. Achieving adequate control of skin toxicity in these cases often requires immunosuppressive systemic therapies and/or interruption of ICI treatment, presenting a therapeutic challenge in the context of cancer management. In this study, we present a case series from Italy based on a multicenter, retrospective, observational study, which included 45 patients treated with ICIs who developed ICI-induced bullous pemphigoid. In addition, we performed a comprehensive review to identify the cases reported in the literature on ICI-induced autoimmune bullous diseases. Several theories seeking their underlying pathogenesis have been reported and this work aims to better understand what is known so far on this issue.

Case Report: Resolution of Lichen Planus Pemphigoides as an unexpected outcome of SARS-CoV-2 infection

It is well known that viral infections play a relevant role in inducing or protecting from autoimmune diseases, thus representing a major environmental factor in the disruption of the immune system in genetically susceptible individuals. Since the beginning of the Covid-19 pandemic a great number of clinical and epidemiological studies have demonstrated that SARS-CoV-2 infection is no exception to the rule by interfering on many different levels in the normal functioning of our immune system. Even though a growing number of case series and case reports has been cited in the literature linking the infection to the new onset of autoimmune diseases, to date very little has been reported concerning a possible correlation between the virus and the clinical resolution of any kind of autoimmune pathology. Here we describe an interesting case of abrupt and unexpected resolution of Lichen planus pemphigoides mucocutaneous lesions in a fully vaccinated patient after a mildly symptomatic SARS-CoV-2 respiratory infection and we speculate on the possible underlying mechanisms correlating the two events.

Lichen Planopilaris Pemphigoides: A Novel Bullous Dermatosis Due to Programmed Cell Death Protein-1 Inhibitor Therapy

ABSTRACT

Lichen planus pemphigoides (LPPemph), apart from bullous pemphigoid, is a rare bullous dermatosis that can be induced by programmed cell death protein-1 (PD-1)/PD ligand 1 (PD-L1) inhibitors. The primary location of PD-1/PD-L1 inhibitor-induced LPPemph has previously only been reported at the nonfollicular dermal-epidermal junction. We present a case of nivolumab-induced LPPemph with an intense perifollicular lichenoid reaction, prominent multifocal perifollicular clefting, which in addition, was also accompanied by linear IgG and C3 immunofluorescence deposits along the dermal-epidermal junction as well as demonstrating a perifollicular pattern. Intriguingly, the serological study of BP180 and BP230 antibodies was negative, suggesting the presence of additional novel antibodies, which primarily favor hair follicles and may contribute to the pathogenesis. Therefore, we consider this entity a novel variant of PD-1/PD-L1 inhibitor-induced bullous dermatosis. To the best of our knowledge, this is the first report that highlights perifollicular bullae accompanied by immunofluorescence findings in a PD-1/PD-L1 inhibitor-induced lesion. We propose a new immunotherapy associated entity, lichen planopilaris pemphigoides, and emphasize the significance of perifollicular changes in the pathogenesis.

Prevalence, Spectrum and Clinical Implications of Malignancies in Patients with Bullous Pemphigoid

Current research on the malignancy rate and spectrum of malignancies in patients with bullous pemphigoid is contradictory. The aims of this study were to determine the prevalence and spectrum of malignancy in patients with bullous pemphigoid and to compare demographic, clinical, therapeutic and outcome data between bullous pemphigoid patients with and without malignancy. This retrospective cohort study enrolled 335 patients (194 women and 141 men; mean age at diagnosis of bullous pemphigoid 77.5 ± 12 years) followed up at an Israeli tertiary centre between January 2009 and December 2019: 107 (32%) had malignancy and 228 (68%) did not. Malignancy occurred before and after bullous pemphigoid diagnosis in 82 (77%) and 25 (23%) patients, respectively. Bullous pemphigoid patients with cancer were older (p = 0.02) and had a higher mortality rate (p < 0.0001) than those without malignancy. The 2 groups did not differ in terms of sex, comorbidities, or clinical characteristics. Those who developed malignancy before bullous pemphigoid were younger than those who developed malignancy after bullous pemphigoid (mean age 69.3 vs 82.4 years, p < 0.0001). Overall malignancy rates did not differ between patients with bullous pemphigoid and the general population; therefore, comprehensive malignancy workup may be unnecessary. However, patients with bullous pemphigoid had a greater risk of melanoma (10.7% vs 4.3%, p = 0.0005); therefore, routine skin screening may be recommended.

Painless Plaques Evolving to Bullae and Painful Erosions on the Penis: A Quiz

Abstract is missing (Quiz)

Case report: Successful treatment of non-bullous lichen planus pemphigoides with dupilumab

Lichen planus pemphigoides (LPP) is a rare autoimmune bullous disease, characterized by the coexistence of lichen planus and subepidermal bullae. However, the minority of LPP patients present with papules rather than vesicles or blisters, which is defined as non-bullous LPP. The diagnosis of LPP relies on manifestations, histopathology, serological assay, and direct immunofluorescence of linear disposition of IgG and/or C3 at the basement membrane zone. Up to now, no standard therapeutic strategies have been proposed for the treatment of LPP. Herein, we describe an uncommon non-bullous LPP patient with widespread papules and erythema, probably induced by vaccination. During hospitalization, he had a poor response to the conventional treatment of topical and systemic corticosteroids, and his condition was finally alleviated by the addition of dupilumab. For LPP patients with a traditional medication failure, or who were not suitable for a higher dose of corticosteroids, a combination with dupilumab could be an alternative option.

[Rare variants of pemphigoid diseases]

Pemphigoid diseases comprise a heterogeneous group of subepidermal autoimmune blistering dermatoses characterized by autoantibodies against structural proteins of the dermal-epidermal junction. Recent decades have witnessed a significant surge in the incidence of these diseases, which, in addition to general aging of the population, can be attributed to the availability of precise diagnostic methods and improved knowledge of the clinical and immunopathological spectrum. While bullous pemphigoid, mucous membrane pemphigoid, and linear IgA disease account for most pemphigoid disorders, less frequent, presumably underdiagnosed variants are increasingly becoming relevant for clinicians. These include epidermolysis bullosa acquisita, anti-p200 pemphigoid, pemphigoid gestationis, lichen planus pemphigoides, and recently defined entities such as IgM pemphigoid and Orf-induced pemphigoid. Accurate characterization and differentiation of these subtypes are not only of diagnostic relevance but may also be associated with therapeutic and prognostic implications for affected individuals. Due to the rarity of these diseases, no controlled prospective clinical trials currently exist, making their diagnosis and therapy challenging.

Esophageal lichen planus: Current knowledge, challenges and future perspectives

Lichen planus (LP) is a frequent, chronic inflammatory disease involving the skin, mucous membranes and/or skin appendages. Esophageal involvement in lichen planus (ELP) is a clinically important albeit underdiagnosed inflammatory condition. This narrative review aims to give an overview of the current knowledge on ELP, its prevalence, pathogenesis, clinical manifestation, diagnostic criteria, and therapeutic options in order to provide support in clinical management. Studies on ELP were collected using PubMed/Medline. Relevant clinical and therapeutical characteristics from published patient cohorts including our own cohort were extracted and summarized. ELP mainly affects middle-aged women. The principal symptom is dysphagia. However, asymptomatic cases despite progressed macroscopic esophageal lesions may occur. The pathogenesis is unknown, however an immune-mediated mechanism is probable. Endoscopically, ELP is characterized by mucosal denudation and tearing, trachealization, and hyperkeratosis. Scarring esophageal stenosis may occur in chronic courses. Histologic findings include mucosal detachment, T-lymphocytic infiltrations, epithelial apoptosis (Civatte bodies), dyskeratosis, and hyperkeratosis. Direct immuno-fluorescence shows fibrinogen deposits along the basement membrane zone. To date, there is no established therapy. However, treatment with topical steroids induces symptomatic and histologic improvement in two thirds of ELP patients in general. More severe cases may require therapy with immunosuppressors. In symptomatic esophageal stenosis, endoscopic dilation may be necessary. ELP may be regarded as a precancerous condition as transition to squamous cell carcinoma has been documented in literature. ELP is an underdiagnosed yet clinically important differential diagnosis for patients with unclear dysphagia or esophagitis. Timely diagnosis and therapy might prevent potential sequelae such as esophageal stenosis or development of invasive squamous cell carcinoma. Further studies are needed to gain more knowledge about the pathogenesis and treatment options.

Effective treatment of refractory lichen planus pemphigoides with a Janus kinase-1/2 inhibitor

Lichen planus pemphigoides is a rare autoimmune subepidermal blistering disease clinically and histopathologically characterized by features of lichen planus and bullous pemphigoid. We describe a case of refractory lichen planus pemphigoides successfully treated with the selective and reversible Janus kinase-1/2 inhibitor, baricitinib.

Unmet Medical Needs in Chronic, Non-communicable Inflammatory Skin Diseases

An estimated 20-25% of the population is affected by chronic, non-communicable inflammatory skin diseases. Chronic skin inflammation has many causes. Among the most frequent chronic inflammatory skin diseases are atopic dermatitis, psoriasis, urticaria, lichen planus, and hidradenitis suppurativa, driven by a complex interplay of genetics and environmental factors. Autoimmunity is another important cause of chronic skin inflammation. The autoimmune response may be mainly T cell driven, such as in alopecia areata or vitiligo, or B cell driven in chronic spontaneous urticaria, pemphigus and pemphigoid diseases. Rare causes of chronic skin inflammation are autoinflammatory diseases, or rheumatic diseases, such as cutaneous lupus erythematosus or dermatomyositis. Whilst we have seen a significant improvement in diagnosis and treatment, several challenges remain. Especially for rarer causes of chronic skin inflammation, early diagnosis is often missed because of low awareness and lack of diagnostics. Systemic immunosuppression is the treatment of choice for almost all of these diseases. Adverse events due to immunosuppression, insufficient therapeutic responses and relapses remain a challenge. For atopic dermatitis and psoriasis, a broad spectrum of innovative treatments has been developed. However, treatment responses cannot be predicted so far. Hence, development of (bio)markers allowing selection of specific medications for individual patients is needed. Given the encouraging developments during the past years, we envision that many of these challenges in the diagnosis and treatment of chronic inflammatory skin diseases will be thoroughly addressed in the future.

Severe childhood lichen planus pemphigoides after hepatitis A vaccination

Background

Lichen planus (LP) pemphigoides (LPP) is a very rare autoimmune bullous disorder, that is, exceptional in children.

Case Report

We report a case of LP pemphigoides with severe cutaneous and mucosal involvement in an 8‐year‐old girl who consulted for multiple vesicular and bullous lesions associated with shiny erythematous‐purple plaques. The eruption occurred 2 months after vaccination against hepatitis A virus. The diagnosis of LP pemphigoides was confirmed by histopathology and immunofluorescence examination. The patient received oral corticosteroid therapy with rapid improvement.

Conclusion

To our knowledge, this is the first report of LPP following hepatitis A vaccination, among adults and children.

Lichen Planus Pemphigoides Associated With PD-1 and PD-L1 Inhibitors: A Case Series and Review of the Literature

ABSTRACT

Immune checkpoint inhibitors are increasingly being used in the treatment of various solid organ and hematologic malignancies. Dermatologic toxicities associated with programmed cell death protein-1 (PD-1) and programmed death ligand-1 (PD-L1) therapy have been widely reported in the literature. It is important for clinicians to be aware of these toxicities to ensure prompt recognition and treatment. Herein, we present the clinical, histopathologic, and immunofluorescence findings of 3 patients diagnosed with lichen planus pemphigoides (LPP) after treatment with anti-PD-1 inhibitors. We also reviewed the literature and summarize 7 previously reported cases of LPP associated with anti-PD-1 and anti-PD-L1 inhibitors. LPP was diagnosed at a median time of 24.4 weeks (range: 4-78 weeks) after initiation of immunotherapy. Clinical findings included papules, plaques, erosions, vesicles, and bullae on the trunk and extremities. Oral involvement was present in half the cases. Histopathologic features of immunotherapy-induced LPP included lichenoid or vacuolar interface dermatitis, the presence of eosinophils, and subepidermal bullae. Direct immunofluorescence demonstrated linear deposition of immunoglobulin G (IgG) or C3. Indirect immunofluorescence demonstrated linear IgG along basement membrane zone on monkey esophagus in 2 cases and linear IgG on the epidermal side of salt split skin in 3 cases. Serum anti-BP180 was elevated in all cases in which enzyme-linked immunosorbent assay was performed.

Strategies to Improve Outcomes of Bullous Pemphigoid: A Comprehensive Review of Clinical Presentations, Diagnosis, and Patients' Assessment

Bullous pemphigoid (BP) is the most frequent autoimmune bullous disease mainly affecting elderlies. Diagnosis usually results from clinical features, histological examination, and the quantification of circulating typical autoantibodies, due to its higher incidence in elderly patients, bullous pemphigoid treatment and management still represents a challenge due to the higher frequency of several comorbidities in this group of patients, which may also be linked to a reduced tolerance to BP treatments. Hence, an early diagnosis and a prompt correct treatment are mandatory to reach better clinical outcomes and improve as much as possible BP outcomes. Herein, we carried out a comprehensive literature review about the known clinical presentations, diagnosis, assessment and monitoring procedures used in daily clinical practice in patients with BP, to better define strategies to improve as much as possible BP clinical outcomes.

Lichen Planus Pemphigoides: a unique form of bullous and lichenoid eruptions secondary to nivolumab

The widespread use of PD‐1 inhibitors to treat various solid tumors has brought certain challenges for the clinician, including immune‐related adverse events (irAEs). Cutaneous toxicities are among the most observed irAEs. Bullous and lichenoid dermatoses following PD‐1 inhibitor therapy have been described. Here we report a novel case of lichen planus pemphigoides, featuring characteristics of both bullous pemphigoid and lichen planus, in a patient treated with nivolumab for renal cell carcinoma. We subsequently review all three cutaneous conditions which may arise in the context of PD‐1 inhibitor therapy.

Challenges and pitfalls between lichen planus pemphigoides and bullous lichen planus

Lichen planus pemphigoides (LPP) and bullous lichen planus (BLP) are rare dermatoses, which are characterised by blisters and lichenoid lesions. Their clinical presentation is heterogenous, displaying overlapping features or mimicking other dermatological diseases. Therefore, diagnosis can often be challenging, requiring a thorough dermatological examination along with distinctive histological and immunopathological characteristics. Lichenoid degeneration of the basal epidermis exposes various antigens of the dermal-epidermal junction in LPP, resulting in the breakdown of immune tolerance, hence, the production of autoantibodies against type XVII collagen. Conversely, no pathogenic autoantibodies are detected in BLP. However, some cases of mucosal lichen planus might display immunopathological features suggestive of autoimmune blistering diseases. Therefore, a better understanding of the pathophysiology of these two distinct dermatoses is imperative. The aim of this review was to provide a summary of the current knowledge on the clinical hallmarks, diagnosis and available therapeutic options in LPP and BLP.

Lichen Planus

Lichen planus (LP) is a T cell-mediated disease affecting the stratified squamous epithelia of the skin and/or mucus membrane. Histologically, the disease is characterized by a lichenoid inflammatory infiltrate and vacuolar degeneration of the basal layer of the epidermis. LP has three major subtypes: Cutaneous, mucosal and appendageal LP. Rarely, it may affect the nails in the absence of skin and/or mucosal changes. LP may also be induced by several drugs, typically anti-hypertensive medication or be associated with infections, particularly viral hepatitis. The diagnosis is based on the clinical presentation and characteristic histological findings. Although the disease is often self-limiting, the intractable pruritus and painful mucosal erosions result in significant morbidity. The current first-line treatment are topical and/or systemic corticosteroids. In addition, immunosuppressants may be used as corticosteroid-sparing agents. These, however are often not sufficient to control disease. Janus kinase inhibitors and biologics (anti-IL-12/23, anti-IL17) have emerged as novel future treatment options. Thus, one may expect a dramatic change of the treatment landscape of LP in the near future.

Pediatric lichen planus: a systematic review of 985 published cases

BACKGROUND

Lichen planus (LP) is a chronic inflammatory disorder usually occurring in middle-aged adults. Data are scarce in the pediatric population.

OBJECTIVE

To describe the patients' characteristics, clinical presentation, and management of pediatric LP.

METHODS

A systematic literature review of pediatric LP was performed in the Medline and Cochrane databases up to February 1, 2020. Demographic and clinical data were extracted for analysis, in addition to laboratory and histology findings, treatments used, and response to treatment. LP pemphigoides (LPP) was further pooled for a subcategory analysis.

RESULTS

One hundred and sixty-four articles were included representing 985 patients. The most common country of origin was India. The most common clinical signs were flat-topped papules (51%); the linear variant was present in 9%. Oral involvement was present in 22%. The most commonly used treatment was topical corticosteroids followed by systemic corticosteroids. The mean duration of treatment was 124.4 days. LPP patients had a short disease duration before diagnosis (4.1 months, P < 0.001) and failed previous treatment more frequently (P < 0.001). Systemic corticosteroids were more often prescribed in this subgroup (75%, P < 0.001) with more recurrence after treatment (31%, P = 0.048).

LIMITATIONS

Lack of randomized controlled studies, in addition to publication bias.

CONCLUSION

In children, LP had a wide polymorphous clinical presentation, and the reported cases were mostly from India. The linear variant was more common and the oral mucosa was less affected in children. LPP, a rare subtype in children, was treated with systemic corticosteroids and recurred more frequently.

Isotopic response of labetalol-associated lichen planus pemphigoides on an old radiation site: A case report

Over the years, the occurrences of different types of skin disorders arising from radiation sites have been observed and studied. Examples include autoimmune blistering diseases such as pemphigus, pemphigoid, and interface or inflammatory reaction patterns such as lichen planus, lupus erythematosus, and Stevens-Johnson syndrome. The phenomenon whereby a new skin disorder arises from a previously healed or irradiated site is called an isotopic response, described as a type of Koebner phenomenon. Ionizing radiation itself can profoundly affect the skin. Both early and late changes can present, which typify the progression of changes following irradiation of the skin. Herein, we report a rare case of labetalol-associated lichen planus pemphigoides that occurred at the site treated with radiation for a soft tissue malignancy after 19 years as a result of an isotopic response. The rash was well-controlled after therapy and kept a 4-year remission. The same skin reaction recurred after the reintroduction of labetalol 4 years later.

Lichen planus - a clinical guide

Lichen planus (LP) is a chronic lichenoid inflammatory disorder of the skin, mucosa and of the appendages. LP is classically characterized by the presence of a rich infiltration of inflammatory T cells, which migrate in the upper part of the dermis, arranged in a band-like pattern. Different sub types of the disease have been so far described. Albeit LP is clinically well defined, the disease still represents a therapeutic enigma. Especially with regard to mucosal or scalp affecting LP types, which often present a recalcitrant and treatment unresponsive course, efficacious therapeutic options are still lacking. Thus, LP represents a disease with a high psychosocial burden. Yet, development in the deciphering of LP pathogenesis reveals possible new druggable targets, thus paving the way for future therapeutic options. In this clinical guide, we summarize the current clinical knowledge and therapeutic standards and discuss the future perspective for the management of LP.

Coexistence of oral mucous membrane pemphigoid and lichenoid drug reaction: a case of toripalimab-triggered and pembrolizumab-aggravated oral adverse events

Toripalimab and pembrolizumab belong to anti-programmed death receptor-1 monoclonal antibodies for the treatment of various cancers. Anti-programmed death receptor-1 therapy can cause mucocutaneous adverse events. Here, we report the first case, to our knowledge, of oral mucous membrane pemphigoid and lichenoid reaction triggered by toripalimab and aggravated by switching to pembrolizumab. Mucous membrane pemphigoid was a definite diagnosis, whereas lichenoid reaction was a clinical diagnosis without pathologic evidence. Although discontinuation of the culprit drugs achieved clinical resolution in most reported cases, multiple studies demonstrated statistically significant associations between the development of dermatologic adverse events and superior clinical outcomes. Thus, more studies are needed to find satisfactory measures in terms of both cancer control and avoidance of severe adverse events.

Current approaches to the diagnosis of autoimmune bullous dermatoses

A modern review of highly effective methods for the diagnosis of autoimmune bullous dermatoses are presented. The specificity of the production of autoantibodies underlying bullous dermatoses are described. Considering the severity of the disease and a significant deterioration in the quality of life of patients suffering from bullous dermatoses; the systematization of diagnostic criteria will help improve the prognosis and management of patients; and it will also help optimize work on the development of targeted drugs for the treatment of patients with this pathology.

Subepithelial autoimmune blistering dermatoses: Clinical features and diagnosis

Subepithelial autoimmune blistering dermatoses are a group of rare skin disorders that are characterized by the disruption of the dermal-epidermal junction through the action of autoantibodies. The third article in this continuing medical education series explores the background, epidemiology, clinical features, and diagnostic criteria of each of the major subepithelial autoimmune blistering dermatoses, including bullous pemphigoid, pemphigoid gestationis, lichen planus pemphigoides, mucous membrane pemphigoid, linear IgA bullous dermatosis, and dermatitis herpetiformis.