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.

Major histocompatibility complex (MHC) gene frequency in acquired dermal macular hyperpigmentation: a case control study

BACKGROUND

Human leukocyte antigen (HLA) allele frequencies have a known association with the pathogenesis of various autoimmune diseases.

METHODS

We recruited 31 Indian patients of acquired dermal macular hyperpigmentation (ADMH) and 60 unrelated, age-and-gender-matched healthy controls. After history and clinical examination, 5 ml of blood in EDTA vials was collected. These samples were subjected to DNA extraction and the expression of HLA A, B, C, DR, DQ-A, and DQ-B was studied.

RESULTS

There was a predominance of females with a gender ratio of 23 : 8 and the most common phototype was Fitzpatrick type IV (83.9%). There was a significant association of HLA A*03:01 (OR: 5.8, CI: 1.7-17.0, P = 0.005), HLA B*07:02 (OR: 5.3, CI: 1.9-14.6, P = 0.003), HLA C*07:02 (OR: 4.3, CI: 1.8-9.6, P = 0.001), HLA DRB1*10:01 (OR: 7.6, CI: 1.7-38.00, P = 0.022), and HLA DRB1*15:02 (OR: 31.0, CI: 4.4-341.8, P < 0.001) with patients compared to controls, whereas HLA DQB*03:01 was less associated with patients compared to controls (OR: 0.2, CI: 0.0-0.6, P = 0.009).

CONCLUSION

Patients with ADMH are more likely to have the HLA A*03:01, HLA B 07*02, HLA C*07:02, HLA DRB1*10:01, HLA DRB1*15:02 and less likely to have the HLA DQB*03:01 allele. Larger cohort studies may thus be conducted studying these specific alleles.

Acquired dermal macular hyperpigmentation: an overview of the recent updates

Acquired dermal macular hyperpigmentation (ADMH), previously known as macular pigmentation of uncertain etiology (MPUE), is an umbrella concept that unifies the distinct but overlapping acquired dermal pigmentary disorders like lichen planus pigmentosus, ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis and pigmented contact dermatitis. All of these disorders usually lack a clinically apparent inflammatory phase, are characterised by dermal pigmentation clinically and histologically, and have a variable protracted disease course. Recently, a proposal has been made to classify these disorders into those with and without contact sensitisation. Dermoscopy is essentially similar across the spectrum of these disorders, and is useful for diagnosis and therapeutic response monitoring. Scoring system has been validated for the same. The treatment of ADMH remains challenging, with multiple topicals, oral therapies including mycophenolate mofetil, and lasers tried. Need of the hour is randomised controlled trials to enhance the therapeutic armamentarium.

A Case of Pigmented Macules Occurring After Ocular Myasthenia Gravis

Lichen planus pigmentosus inversus (LPP-I) is characterized by the presence of hyperpigmented or hypopigmented lesions on the flexural surfaces of the body. It is a rare variant of lichen planus pigmentosus with unknown etiology. We report a case of a male presented with LPP-I three months after diagnosis of ocular myasthenia gravis, highlighting the possible autoimmune association.

A Delphi consensus on the nomenclature and diagnosis of lichen planus pigmentosus and related entities

BACKGROUND

Although well known in clinical practice, research in lichen planus pigmentosus and related dermal pigmentary diseases is restricted due to lack of consensus on nomenclature and disease definition.

AIMS AND OBJECTIVES

Delphi exercise to define and categorise acquired dermal pigmentary diseases.

METHODS

Core areas were identified including disease definition, etiopathogenesis, risk factors, clinical features, diagnostic methods, treatment modalities and outcome measures. The Delphi exercise was conducted in three rounds.

RESULTS

Sixteen researchers representing 12 different universities across India and Australia agreed to be part of this Delphi exercise. At the end of three rounds, a consensus of >80% was reached on usage of the umbrella term 'acquired dermal macular hyperpigmentation'. It was agreed that there were minimal differences, if any, among the disorders previously defined as ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis and pigmented contact dermatitis. It was also agreed that lichen planus pigmentosus, erythema dyschromicum perstans and ashy dermatosis did not differ significantly apart from the sites of involvement, as historically described in the literature. Exposure to hair colours, sunlight and cosmetics was associated with these disorders in a significant proportion of patients. Participants agreed that both histopathology and dermatoscopy could diagnose dermal pigmentation characteristic of acquired dermal macular hyperpigmentation but could not differentiate the individual entities of ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis, lichen planus pigmentosus and pigmented contact dermatitis.

LIMITATIONS

A wider consensus involving representatives from East Asian, European and Latin American countries is required.

CONCLUSION

Acquired dermal macular hyperpigmentation could be an appropriate conglomerate terminology for acquired dermatoses characterised by idiopathic or multifactorial non-inflammatory macular dermal hyperpigmentation.

Acquired Dermal Macular Hyperpigmentation: An Update

Acquired dermal macular hyperpigmentation (ADMH) is an umbrella term that includes disorders clinically characterized by small and large pigmented macules/patches and histopathologically showing an evidence of current or resolved interface dermatitis with pigment incontinence, without clinically significant prior inflammatory phase. The term intends to include diseases previously described in the literature as lichen planus pigmentosus, Riehl's melanosis/pigmented cosmetic dermatitis and ashy dermatosis/erythema dyschromicum perstans. The nomenclature and origin of these disorders have always been a matter of discussion. These disorders share many clinicopathological similarities, are difficult to treat and adversely affect the quality of life. Recent consensus points towards the need for a unifying term to facilitate research and therapeutic trials. This article aims to provide a comprehensive review of the recent advances in ADMH.

Psychosocial burden of lichen planus pigmentosus is similar to vitiligo, but greater than melasma: A cross-sectional study from a tertiary-care center in north India

BACKGROUND

Lichen planus pigmentosus can have a negative impact on the quality of life; however, this has not been studied in detail.

OBJECTIVES

To study the quality of life in patients with lichen planus pigmentosus and compare it with patients with vitiligo and melasma.

METHODS

This was a cross-sectional study conducted in a tertiary-care center in north India from January 2018 to May 2019. Patients ≥ 18 years of age with lichen planus pigmentosus (n = 125), vitiligo (n = 113) and melasma (n = 121) completed the Dermatology Life Quality Index (DLQI) questionnaire and answered a global question on the effect of disease on their lives. In addition, patients with vitiligo completed the Vitiligo Impact Scale (VIS)-22 questionnaire, while those with lichen planus pigmentosus and melasma filled a modified version of VIS-22.

RESULTS

The mean DLQI scores in patients with lichen planus pigmentosus, vitiligo and melasma were 10.9 ± 5.95, 9.73 ± 6.51 and 8.39 ± 5.92, respectively, the difference being statistically significant only between lichen planus pigmentosus and melasma (P < 0.001). The corresponding mean modified VIS-22/VIS-22 scores were 26.82 ± 11.89, 25.82 ± 14.03 and 18.87 ± 11.84, respectively. This difference was statistically significant between lichen planus pigmentosus and melasma, and between vitiligo and melasma (P < 0.001 for both). As compared to vitiligo, patients with lichen planus pigmentosus had a significantly greater impact on "symptoms and feelings" domain (P < 0.001) on DLQI, and on "social interactions" (P = 0.02) and "depression" (P = 0.04) domains on VIS-22. As compared to melasma, patients with lichen planus pigmentosus had significantly higher scores for "symptoms and feelings," "daily activities," "leisure" and "work and school" domains of DLQI, and all domains of VIS-22. Female gender was more associated with impairment in quality of life in patients with lichen planus pigmentosus, while lower education, marriage, younger age and increasing disease duration showed a directional trend.

LIMITATIONS

Use of DLQI and modified version of VIS-22 scales in the absence of a pigmentary disease-specific quality-of-life instrument.

CONCLUSION

Patients with lichen planus pigmentosus have a significantly impaired quality of life. The psychosocial burden of lichen planus pigmentosus is quantitatively similar to that of vitiligo, but significantly greater than melasma.

Oral Lichen Planus Associated With Lichen Planus Pigmentosus and Lichen Sclerosus in Monozygotic Twins

ABSTRACT

Lichen planus (LP) is a mucocutaneous immune-mediated disease of unknown etiology. It is more prevalent in women and usually occurs between the third and sixth decades of life. Oral lesions may or may not be associated with skin and genital lesions. Although the role of genetic factors is still undetermined, reports of LP in more than one family member are not uncommon. However, the occurrence of LP in monozygotic twins is rare. We report a rare case of 42-year-old female monozygotic twins presenting oral LP. This report is even rarer because one of the patients had cutaneous lesions of an unusual variant of LP (LP pigmentosus) and the other had an uncommon association with lichen sclerosus. The etiology and pathogenesis of LP are still uncertain. However, despite being rare, its occurrence in family members and monozygotic twins suggests that genetic factors are involved in its development.

[Oral tranexamic acid in the treatment of lichen planus pigmentosus: A prospective study of 20 cases]

INTRODUCTION

Lichen planus pigmentosus is a variant of lichen planus that is particularly difficult to treat. The aim of this study was to evaluate the efficacy and safety of tranexamic acid in lichen planus pigmentosus.

PATIENTS AND METHODS

This prospective study, conducted at the University Hospital of Casablanca from August 2017 to June 2019, included 20 patients with histologically confirmed lichen planus pigmentosus. The exclusion criteria were pregnancy, breastfeeding, known hypersensitivity to tranexamic acid, and thromboembolic disease. Evaluation was carried out by means of clinical examination and measurement of the affected area using the Visioface® RD hardware package at 6 and 12 months (M6 and M12).

RESULTS

Eighteen women and 2 men with an average age of 49 years (range: 26-65 years) were included. All patients were phototype 3 or 4. The average disease duration was 2.9 years (range: 2 months-15 years). Pigmented, slate-grey, well-delineated macules were observed in all patients on the face (n=19), neck (n=14) or arms (n=2). Pruritus was present in 9 patients. All patients received oral tranexamic acid 250mg/d for 4 to 6 months with external photoprotection that was prolonged beyond 6 months. At M6, partial improvement was noted in 10 patients, 3 patients showed no improvement, and 7 patients were lost to follow-up. Pruritus disappeared in all patients and no relapse was seen at M12.

DISCUSSION

Our study suggests that tranexamic acid could be an effective treatment for lichen planus pigmentosus with a good safety profile. However, the limitations of the study are the limited population and the high number of patients lost to follow-up at M6. Larger-scale studies are needed to provide more detailed results.