Erythema dyschromicum perstans and lichen planus: are they related?

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.

[Hyperpigmentation]

The key diagnostic tool for hyperpigmentation is histopathology, which may be accompanied by certain laboratory tests. Hyperpigmentation may result from excess melanin (hypermelanosis), cutaneous iron deposits (hemosiderosis), cutaneous carotene deposits (carotenoderma), or cutaneous deposits of a substance not normally found in the skin (dyschromia). The different types of hypermelanosis may be classified as either localised or generalised. The former generally correspond to skin tumours and may form a cutaneous expression of complex syndromes, which most notably include cardiac abnormalities, or to pigmented forms of inflammatory and/or infectious dermatoses. Diffuse hypermelanosis is frequently a sign of systemic disease, generally metabolic or endocrine disease, or else it may result from pharmaceutical therapy. Herein we review the various causes of hyperpigmentation and the corresponding therapy.

Erythema dyschromicum perstans: A case report and systematic review of histologic presentation and treatment

Objective

Erythema dyschromicum perstans (EDP) can be difficult to diagnose and treat; therefore, we reviewed the literature to assess whether histology can be used to differentiate lichen planus pigmentosus (LPP) from EDP and determine which treatments are the most effective for EDP. We also present a case of a patient who was treated successfully with narrow-band ultraviolet B (NB-UVB).

Methods

A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was conducted up to July 2017 using four databases.

Results

Histologic analyses from the literature reveal a significant percentage of melanophages, lymphocytic infiltrates, and basal vacuolar degeneration in EDP, and a significant histologic overlap with LPP. The review of the literature on treatment outcomes showed that NB-UVB and tacrolimus were effective with minimal side effects. Clofazimine was effective, but demonstrated significant-to-intolerable side effects. Griseofulvin, isotretinoin, and dapsone provided unsatisfactory results as lesions recurred after discontinuation. Lasers were largely ineffective and may cause postinflammatory hyperpigmentation and fibrosis.

Conclusion

A diagnosis of EDP should not be based on histologic findings alone. Clinical history, morphology, and distribution should be used to differentiate EDP and LPP. NB-UVB and tacrolimus are promising treatments for EDP with minimal side effects. This is the first report to our knowledge of sustained resolution of EDP after treatment with NB-UVB at long-term follow-up of 4 years. Larger studies are needed to confirm these findings.

Segmental lichen planus pigmentosus: An unusual presentation

Lichen planus pigmentosus (LPP) is a distinct clinical entity commonly encountered in the Indian population. It is considered a variant of lichen planus (LP). A 40-year-old male presented with asymptomatic hyperpigmented macules in a segmental distribution since 10 years that were clinically and histopathologically suggestive of LPP. We propose the terminology “segmental lichen planus pigmentosus” and report this unusual presentation.

Immunopathologic study of erythema dyschromicum perstans (ashy dermatosis)

Erythema dyschromicum perstans (EDP) is a pigmentary disease of unknown etiology in which damage to basal cells is thought to be mediated by adhesion molecules. The aim of this study was to characterize the histopathology and immunopathology of EDP. Forty-three patients from Medellín, Colombia, with the diagnosis of EDP were evaluated. Skin biopsy specimens were obtained for histopathology and immunohistochemistry, using monoclonal antibodies directed against the following markers: CD4, CD8, CD56, CD1a, CD68, CLA, HLA-DR, ICAM-1 and LFA-1alpha. A dermal lymphocytic infiltrate was observed in all cases, with a perivascular location in 86%. Other histologic features included melanophages in all specimens, vacuolization of the basement membrane zone (BMZ) 58% and exocytosis of lymphocytes (53.5%). The mean number of total leukocytes was 1510 cells mm-2 of tissue. There was a predominance of CD8+ T lymphocytes in the dermis and HLA-DR+, ICAM-1+ keratinocytes in the epidermis. Exocytosis of cutaneous lymphocyte antigen (CLA)+cells was observed in areas of BMZ damage, suggesting that response to antigenic stimulation may play a role in the development of EDP.

HLA-DR association with the genetic susceptibility to develop ashy dermatosis in Mexican Mestizo patients

BACKGROUND

Ashy dermatosis, also known as erythema dyschromicum perstans, is an acquired benign disease, characterized by blue-gray pigment patches with erythematous borders. The cause is still unclear, but probably has an immunologic basis.

OBJECTIVE

The aim of this study was to determine gene frequencies of the HLA-DR alleles in Mexican patients with ashy dermatosis and compare them with ethnically matched healthy control subjects to reveal the genetic susceptibility to develop ashy dermatosis.

METHODS

We included 23 consecutive patients with clinical and histopathologic confirmed diagnosis of erythema dyschromicum perstans. Patients and control subjects received a questionnaire to determine their ethnic origin and a peripheral blood sample was taken for DNA extraction. Finally, Genetic HLA-DRB1 was performed by polymerase chain reaction sequence-specific oligonucleotide reverse dot blot hybridization.

RESULTS

Of the 23 patients included in this study, 65% were women and 35% were men. We observed that the disease was located in the trunk in 17 patients (74%) and the upper limbs in 15 patients (65%). The most frequent allele was HLA-DR4 (65%) (pC < 1 x 10(-6), odds ratio = 6.0, 95% confidence interval = 2.8-12.7) whereas in control subjects it was 23%. The most frequent molecular subtype in both patients and healthy control subjects was DRB1( *)0407, being statistically significant after comparing the two groups (pC < 1 x 10(-6), odds ratio = 7.0, 95% confidence interval = 3.1-15.8).

LIMITATIONS

Since this is a disease strongly influenced by ethnicity, extrapolation to other ethnic groups is limited.

CONCLUSIONS

Many factors influence the ethiopathogenesis of erythema dyschromicum perstans, but it is strongly suggested to have an important genetic susceptibility conferred by genes located within the major histocompatibility complex region.

Pigmentary disorders in ethnic skin

Pigmentary disorders are commonly seen in ethnic skin. They are psychologically problematic in darker skin. Treatment of many of these disorders remains difficult.

A study of 124 Indian patients with lichen planus pigmentosus

Lichen planus pigmentosus is a fairly common disorder of pigmentation in Indians, but reports comprising a sizeable number of patients are lacking in the literature. We now describe the clinical and epidemiological features and histopathological findings for 124 lichen planus pigmentosus patients. A retrospective analysis of medical records of patients attending our centre during the past 12 years was undertaken. Of the 124 patients (56 male, 68 female), the majority (48.4%) had the disease for 6 months to 3 years. The face and neck were the commonest sites affected with pigmentation varying from slate grey to brownish-black. The pattern of pigmentation was mostly diffuse (77.4%), followed by reticular (9.7%), blotchy (7.3%) and perifollicular (5.6%). Lichen planus was noted in 19 patients with typical histopathological changes of the disorder. Lichen planus pigmentosus, a distinct clinical entity commonly encountered in the Indian population, should be considered in the spectrum of lichenoid disorders as a variant of lichen planus.

Erythema dyschromicum perstans in prepubertal children

Erythema dyschromicum perstans (EDP) is a rare disorder of pigmentation that is most common in Hispanic patients. In adults, EDP has a slow onset and is unlikely to resolve spontaneously. The etiology and clinical course in children is poorly defined. Physical examinations, chart reviews, and telephone interviews were performed for eight pediatric patients with EDP who were followed at Children's Memorial Hospital in Chicago between 1990 and 1998. All the patients available for long-term follow-up (five of the eight) experienced complete clearance without recurrence in an average of 2.5 years. In all of our patients, the onset was noted from July to December. The administration of aminopenicillins was coincident with the development of EDP in two of the patients. Review of the English-language literature reveals that 25 prepubertal children have previously been reported. Including our patients, 69% of prepubertal children with EDP experienced resolution. We concluded that the clinical course of childhood (prepubertal) EDP differs from that of adult EDP, and it is more likely to resolve within 2-3 years.

Minocycline-induced staining of torus palatinus and alveolar bone

BACKGROUND

Minocycline hydrochloride, an analog of tetracycline, is widely used in the treatment of acne. Its use has been associated with discoloration of teeth, bone, and other tissues.

METHODS

A case is presented involving a patient with minocycline-induced staining of the torus palatinus and alveolar bone.

RESULTS

No treatment was rendered since the patient was not concerned with the appearance of the discoloration. The patient's dermatologist elected to change antibiotics.

CONCLUSIONS

Patients on long-term minocycline therapy should be made aware of the possibility of pigmentation of bone and soft tissue that may be reversible with discontinuation of therapy; however, minocycline-induced staining of the permanent dentition may not be reversible.

Erythema dyschromicum perstans: report of a new case and critical review of the literature

Erythema dyschromicum perstans (EDP), described by Convit et al. in 1961, is a rare dermatosis. Its relationship with ashy dermatosis (AD), described by Ramirez in 1957, is still a matter of debate. We report a typical case of EDP. The patient, of North African origin, had a dyschromic (hypo- and hyperpigmented) eruption on the chest and limbs for 2 years. The lesions were occasionally surrounded by a papular border which spread slowly and centrifugally. Histological examination showed a lichenoid infiltrate. A carcinoma of the lung was simultaneously discovered. No treatment was given, EDP is infrequent and often considered identical to ashy dermatosis in the literature. However, the clinical aspects of the two diseases differ. The main features of these two diseases are reviewed and compared on the basis of a literature review. We conclude that EDP and AD are distinct clinical entities.

Update on oral lichen planus: etiopathogenesis and management

Lichen planus (LP) is a relatively common disorder of the stratified squamous epithelia, which is, in many ways, an enigma. This paper is the consensus outcome of a workshop held in Switzerland in 1995, involving a selection of clinicians and scientists with an interest in the condition and its management. The oral (OLP) eruptions usually have a distinct clinical morphology and characteristic distribution, but OLP may also present a confusing array of patterns and forms, and other disorders may clinically simulate OLP. Lesions may affect other mucosae and/or skin. Lichen planus is probably of multifactorial origin, sometimes induced by drugs or dental materials, often idiopathic, and with an immunopathogenesis involving T-cells in particular. The etiopathogenesis appears to be complex, with interactions between and among genetic, environmental, and lifestyle factors, but much has now been clarified about the mechanisms involved, and interesting new associations, such as with liver disease, have emerged. The management of lichen planus is still not totally satisfactory, and there is as yet no definitive treatment, but there have been advances in the control of the condition. There is no curative treatment available; immunomodulation, however, can control the condition. Based on the observed increased risk of malignant development, OLP patients should be offered regular follow-up examination from two to four times annually and asked to report any changes in their lesions and/or symptoms. Follow-up may be particularly important in patients with atrophic/ulcerative/erosive affections of the tongue, the gingiva, or the buccal mucosa. Much more research is required into the genetic and environmental aspects of lichen planus, into the premalignant potential, and into the possible associations with chronic liver, and other disorders. More clinical studies are required into the possible efficacy of immunomodulatory drugs such as pentoxifylline and thalidomide.

Minocycline-induced intraoral pharmacogenic pigmentation: case reports and review of the literature

Minocycline, a semi-synthetic tetracycline antibiotic, is well documented as being associated with pharmacogenic pigmentation of various tissues in humans and other mammals. The most obvious of these are skin pigmentation, but intraorally include "green" roots of erupted teeth, "black" roots of extracted teeth, a dark stain of the crowns of fully developed teeth, and "black" alveolar bone. This article presents five cases of "black" alveolar bone with photographic documentation of its progress. It also reviews the available English language literature on this phenomenon. The incidence of minocycline staining of alveolar bone is probably 2% of that population taking the drug for 2 months or longer. Presently, minocycline is most widely used in the young adult population for the treatment of acne. With the recent interest in minocycline as a palliative treatment for rheumatiod arthritis, an entirely different population could be experiencing this effect. If minocycline use becomes widespread as a treatment for rheumatoid arthritis, it is likely that more practitioners will be asked to diagnose this sometimes striking, though apparently benign, condition. Recognition of this condition will save the practitioner and the patient from unnecessary concern and surgery.

Idiopathic eruptive macular pigmentation: report of five patients

We report the occurrence of idiopathic eruptive macular pigmentation in four children and one adolescent. This condition appears to be a distinct clinicopathologic and histologic entity. It is characterized by asymptomatic, pigmented macules involving the neck, trunk, and proximal limbs. All patients or their families denied the patients' having taken any drug before the eruption. In all of the patients the first sign was a pigmented spot without preceding erythematous, papular, or hypopigmented lesions. Histologic study showed enhanced epidermal basal layer pigmentation with pigmentary incontinence, a mild perivascular lymphohistiocytic infiltrate, and many melanophages in the papillary dermis. Electron microscopy showed an increased number of melanosomes in basal and suprabasal keratinocytes as well as clustered melanosomes in dermal melanophages. Treatment of this asymptomatic condition is unnecessary because spontaneous resolution of the lesions is to be expected within several months to a few years.

Lines of Blaschko

The lines of Blaschko represent a pattern followed by many skin disorders. We review the clinical and histologic features of X-linked, congenital/nevoid, and acquired skin diseases that follow these lines. We also include cutaneous disorders that have a linear distribution but do not follow Blaschko's lines. Finally, we differentiate Blaschko's lines from other patterns on the skin such as dermatomes and Langer's lines.

Ashy dermatosis and lichen planus pigmentosus: a clinicopathologic study of 31 cases

The clinical and histopathologic characteristics of patients with ashy dermatosis (n = 20) and lichen planus pigmentosus (n = 11) were analyzed. We found significant clinical differences between both dermatoses, supporting our opinion that they are two separate conditions. Both dermatoses were histologically similar.