Genetic mosaicism in an acquired inflammatory dermatosis following the lines of Blaschko

Compound-honeysuckle-induced drug eruption with special manifestations: A case report

BACKGROUND

The clinical manifestations of drug eruption are complex and diverse, which can lead to missed diagnosis or misdiagnosis. The clinical manifestations of drug eruption caused by compound honeysuckle have not been reported.

CASE SUMMARY

A 20-year-old man was admitted to our department of dermatology due to erythema and papules on the chest and abdomen with pruritus for 3 d. The next day after taking compound honeysuckle granules, the patient suddenly developed a rash and intense itching on his chest and abdomen. Physical examination revealed diffuse red needle-cap size macules and papules with well-defined borders on the chest and abdomen, and discoloration after finger pressure. No abnormality was observed in other areas of the skin. Back skin scratch was positive. White blood cells, eosinophil count and eosinophil ratio were higher than normal. Histopathological examination of the skin lesions on the left abdomen revealed intercellular edema, blurred focal basal cell layers, and focal lymphocyte infiltration in the superficial dermis and perivascular areas. Immunohistochemistry showed CD3⁺_, CD4⁺ and CD8⁺ T lymphocytes. The diagnosis was drug eruption with special manifestations induced by compound honeysuckle. The skin lesions completely subsided without pruritus after 2 wk of antihistamine and hormone therapy. Follow-up for > 1 mo showed no recurrence.

CONCLUSION

Chinese patent medicine compound honeysuckle granules can induce allergic reaction and rare skin damage.

Clinical and Therapeutic Aspects of Linear Psoriasis: A Study of 30 Cases

BACKGROUND

Psoriasis affects 2-4% of the population, with the most common clinical type being plaque psoriasis. The linear form of psoriasis is very rare. The literature on linear psoriasis (LP) consists of only case reports, and data are few.

OBJECTIVE

This study aimed to better understand LP in a large-scale study.

PATIENTS AND METHODS

We retrospectively retrieved the medical records from 14 French medical centers of patients newly diagnosed clinically with LP, with or without the support of histology, between 1 February and 31 July 2015. For each case, we assessed the clinical features, treatments and treatment efficacy.

RESULTS

In total, 30 cases of LP (mean age 26.8 years, 13 males) were reported. Mean age at onset of LP was 20.0 years, with 18 developing LP in childhood. Ten patients had a family history of psoriasis, and two had psoriatic arthritis. A total of 19 cases were linear at onset, with concomitant classical psoriasis; these were termed "superimposed" LP. The remaining 11 cases were not associated with classical psoriasis and were termed "isolated" LP. In four of the superimposed cases, LP developed when the patient was receiving systemic treatment: methotrexate (n = 2), etanercept (n = 1) or infliximab (n = 1). Topical steroids were effective in 76% of cases in which they were used, and systemic treatment was effective in < 66%. Treatments were less effective in LP than in classical psoriasis.

DISCUSSION

We identified a wide range of LP, with two profiles: isolated LP and superimposed LP. Topical treatment usually evoked clinical response, with relative resistance to systemic therapy. Methotrexate and anti-tumor necrosis factor (TNF)-α therapies can possibly unmask LP.

Linear Sclerodermoid Lupus Erythematosus Profundus in a Child

Lupus erythematosus panniculitis, also known as lupus profundus, is a variant in the clinicopathological spectrum of lupus erythematosus (LE) affecting about 2%-3% of LE patients. A linear configuration of LE panniculitis has been reported rarely with rare reports describing the coexistence of different forms of cutaneous LE and localized morphea. In this study, the authors present a 9-year-old girl with linear arrangement of subcutaneous nodules on her left forearm. Microscopic findings from 2 biopsies included lymphocytes at the dermoepidermal junction with mild interface dermatitis, a dense lymphocytic infiltrate that was concentrated around adnexae and subcutaneous fat in concert with thickened collagen bundles and mild widening of fibrous septae surrounding fat lobules. Although the clinical differential diagnosis included panniculitis or a sporotrichoid infection, 1 biopsy showed a dense lymphocytic infiltrate histologically bordered on that of cutaneous lymphoid hyperplasia or a late stage of Lyme disease, and a second also demonstrated more prominent sclerodermoid collagen bundles rendering the diagnosis of linear sclerodermoid LE profundus.

The distribution pattern of segmental vitiligo: clues for somatic mosaicism

BACKGROUND

Segmental vitiligo is characterized by a unilateral and localized distribution. So far, the underlying mechanism is still an enigma.

OBJECTIVES

 To get an insight into the aetiopathogenesis of segmental vitiligo by comparison with the distribution pattern of dermatoses with a possible mosaic or neurogenic background.

METHODS

In this retrospective observational study the distribution pattern of 724 unilateral, linear or band-shaped control lesions was compared with 181 segmental vitiligo lesions. Clinical photographs were used to score similarities according to a defined grading system (scale ranging from 0 for no similarities to 4 for complete similarity). Control lesions were evaluated both individually and after grouping into different cell types.

RESULTS

In general, only a minority of cases (36·9%), showed similarities (grade 1-4) between control lesions and segmental vitiligo. Grade 2-4 similarities were seen mainly in segmental lentiginosis (73·7%, P < 0·001). The best grade for correspondence (grade 3-4) was observed significantly more only in segmental lentiginosis (36·8% vs. 3·5%, P<0·001) and epidermal naevus verrucosus (12·5% vs. 3·7%, P=0·008) compared with the other control lesions. The distribution pattern of segmental vitiligo significantly overlapped those of other disorders originating from melanocytes.

CONCLUSIONS

 Our results demonstrate that the distribution pattern of segmental vitiligo is not entirely similar to any other skin disease, although some mosaic skin disorders have more overlap with segmental vitiligo than others. The remarkable clinical similarity with several cases of mosaic diseases involving melanocytes supports the hypothesis that cutaneous mosaicism may be involved in segmental vitiligo.

Concurrence of lichen striatus and localised pityriasis rosea: Cutaneous mosaicism

Cutaneous mosaicism has always been an intriguing subject. A 15-year-old boy presented to us with a unilateral band of lesions of pityriasis rosea and lichen striatus. The case is discussed in the light of the concept of genetic mosaicism.

Lichen striatus occurring after allogenic peripheral blood stem cell transplantation in an adult with aplastic anemia

Lichens striatus (LS) is an acquired, self-limiting inflammatory dermatosis that follows the lines of Blaschko. The etiology of the eruption is unknown, but several theories have been proposed with focus on environmental factors, viral infection, cutaneous injury, hypersensitivity, and genetic predisposition. We describe a 19-year-old woman who developed a unilateral linear eruption 17 months after allogenic peripheral blood stem cell transplantation. Histopathology revealed features, which were consistent with LS. To the best of our knowledge, our patient is the first case describing the appearance of LS occurring after allogenic stem cell transplantation. We speculate that this condition represents an unusual form of localized, chronic graft-versus-host disease.

Patterned disorders in dermatology

The skin gives us an opportunity to study pathologies unapparent in other systems such as patterned disorders. Among the best-identified patterns of skin disorders are the well-known lines of Blaschko, but other types of skin-patterned lesions have also been recognized. This short review will describe and discuss these different patterns and their pathophysiologic mechanisms, such as somatic mosaicism and X-chromosome associated mosaicism. Cutaneous patterned disorders are thought to be associated usually with inherited diseases per se, but in fact they are also reported in so-called acquired diseases. These cases suggest the existence of an underlying defect in a gene closely associated with the disease pathogenesis. The study of these acquired patterned disorders in the future may help us to understand the biologic foundations and pathogenesis of common human diseases.

Linear sclerodermic lupus erythematosus, a distinct variant of linear morphea and chronic cutaneous lupus erythematous

BACKGROUND

Overlap syndromes represent disorders that combine diagnostic criteria of two or more different connective tissue diseases.

METHODS

We herein describe the case of a 34-year-old patient.

RESULTS

Our patient developed a lesion on the scalp and forehead following Blaschko's line typical for linear morphea "en coup de sabre", while histopathological features were consistent with both chronic cutaneous lupus erythematosus and linear morphea, a cutaneous overlap syndrome previously described as linear sclerodermiform lupus erythematosus. The patient was given oral antimalarials in association with topical steroids and calcineurin inhibitors with good response.

CONCLUSIONS

Knowledge of this peculiar cutaneous overlap syndrome is warranted, since its management and prognosis is probably different from classical linear morphea.

Linear morphoea follows Blaschko's lines

BACKGROUND

The aetiology of morphoea (or localized scleroderma) remains unknown. It has previously been suggested that lesions of linear morphoea may follow Blaschko's lines and thus reflect an embryological development. However, the distribution of linear morphoea has never been accurately evaluated.

OBJECTIVES

We aimed to identify common patterns of clinical presentation in children with linear morphoea and to establish whether linear morphoea follows the lines of Blaschko.

METHODS

A retrospective chart review of 65 children with linear morphoea was performed. According to clinical photographs the skin lesions of these patients were plotted on to standardized head and body charts. With the aid of Adobe Illustrator a final figure was produced including an overlay of all individual lesions which was used for comparison with the published lines of Blaschko.

RESULTS

Thirty-four (53%) patients had the en coup de sabre subtype, 27 (41%) presented with linear morphoea on the trunk and/or limbs and four (6%) children had a combination of the two. In 55 (85%) children the skin lesions were confined to one side of the body, showing no preference for either left or right side. On comparing the overlays of all body and head lesions with the original lines of Blaschko there was an excellent correlation.

CONCLUSIONS

Our data indicate that linear morphoea follows the lines of Blaschko. We hypothesize that in patients with linear morphoea susceptible cells are present in a mosaic state and that exposure to some trigger factor may result in the development of this condition.

"Pediatric blaschkitis": expanding the spectrum of childhood acquired Blaschko-linear dermatoses

We describe two young children who developed relapsing, pruritic, papulovesicular eruptions in multiple bands along Blaschko lines on the neck, trunk, and extremities. Skin specimens in both revealed spongiotic dermatitis. This represents the first report of "blaschkitis" in children, providing further evidence that lichen striatus and blaschkitis are related acquired Blaschko-linear dermatoses that exist on a spectrum rather than as the childhood and adult form of a single disease entity. We highlight the features that differentiate blaschkitis from lichen striatus, review the potential roles of cutaneous mosaicism, environmental triggers, and background immunologic state in their pathogenesis, and discuss the spectrum of inflammatory dermatoses that can follow Blaschko lines.

Does Inflammatory Linear Verrucous Epidermal Nevus Represent a Segmental Type 1/Type 2 Mosaic of Psoriasis?

BACKGROUND

A 6-year-old girl with a symmetric linear eruption on both of her legs, clinically and histologically resembling inflammatory linear verrucous epidermal nevus (ILVEN) or linear psoriasis (LP), with concomitant psoriasis of the guttata type and a positive family history of psoriasis is presented. The questions as to whether LP actually exists and ILVEN represents a distinct entity are still under debate.

OBJECTIVE AND METHODS

The recent literature concerning case reports of ILVEN and LP is reviewed.

RESULTS

Case reports of ILVEN and LP can be subdivided into four different groups: (1) ILVEN with or without concomitant psoriasis, only in part reacting to antipsoriatic treatment, (2) ILVEN without concomitant psoriasis, (3) LP with concomitant psoriasis vulgaris, with both groups 2 and 3 reacting successfully to antipsoriatic treatment, and (4) LP without concomitant psoriasis vulgaris and with no family history of psoriasis (very rarely reported).

CONCLUSION

It is hypothesized that inflammatory linear verrucous eruption besides nevoid psoriasis/LP represents a further segmental type 1/type 2 mosaic of psoriasis which, if a (verrucous) epidermal nevus exists, shows a high affinity of occurrence in close context to such a nevus. Heritability is thought to be possible.

A case of linear lichen planus

Linear lichen planus (LLP) is a very rare form of lichen planus (LP) characterized by a linear distribution of the lichenoid lesions. It usually follows the lines of Blaschko with unilateral involvement. We report such a case of LLP. A 50-year-old man presented with slightly pruritic, linear, violaceous, papular lesions on the right side of his jaw. A biopsy specimen demonstrated the typical histology of LP. Based on the clinical and pathological findings, the diagnosis was LLP.

Atopic dermatitis with increased severity along a line of Blaschko

Several primarily symmetric skin diseases may, on rare occasions, manifest themselves more prominently along the embryonic migration pathways of cutaneous cell clones. Loss of heterozygosity along these lines of Blaschko resulting in hemizygosity or homozygosity of alleles predisposing for the disease is the most likely explanation for this phenomenon. Here, we report a case of severe Blaschko linear atopic dermatitis superimposed on a milder symmetric eruption of atopic eczema in a 36-year-old man with personal and familial history of allergy. Continuous transition of linear atopic eczema to linear vesicular (dyshidrotic) plantar eczema demonstrates the relationship between these two entities. Individuals such as our patient offer an opportunity to identify intraindividual genetic variations marking loci involved in the pathogenesis of atopy and atopic eczema.

Linear hyperpigmentation with extensive epidermal apoptosis: a variant of linear lichen planus pigmentosus?

We report 3 female patients who rapidly developed pigmented patches in a linear arrangement. Histologically there was minimum epidermal basal cell damage and bandlike lymphocyte infiltration in the dermis, but focal massive apoptotic materials positively stained with antikeratin antibody were prominently seen in the papillary and subpapillary dermis. We considered these cases as a variant of linear lichen planus pigmentosus with unique histologic change of severe epidermal apoptosis. These histologic features may represent a severe apoptotic change in the end stage of lichenoid tissue reaction.

Lichen striatus in adults or 'adult blaschkitis'? There is no need for a new naming

BACKGROUND

Lichen striatus (LS) is a well-known acquired linear inflammatory dermatosis. In 1990, Grosshans and Marot introduced the term 'adult blaschkitis' (AB), describing an eruption similar to LS occurring in an adult (adult LS). Does there really exist a new entity or a need for a new naming?

OBJECTIVE AND METHODS

Two new cases of adult LS are described and the data from 16 earlier cases (12 AB and 4 adult LS) are reviewed.

RESULTS

The analysis of 18 adult patients with an acquired inflammatory blaschkolinear eruption reveals that females are affected two times as frequently as males. The mean age at onset is 44 years, the mean duration until spontaneous cure 8.7 months. Relapses occur in 27.7%. In 78%, the eruption is localized on the trunk, in 55% on the arms and in 50% on the legs. Multilinearity is found in 100% if the eruption is on the trunk, and 61.5% if it is on the limbs. Neither clinical nor morphological differences exist between AB and adult LS.

CONCLUSION

There are no convincing characteristics which justify creating a new name or even a new entity. AB may be the same as LS, a well-known acquired linear inflammatory dermatosis, which--as has been shown now--does not occur so rarely in adults. However, the etiology of this entity remains obscure.

Meyerson phenomenon within a nevus flammeus. The different eczematous reactions within port-wine stains

Only few reports about eczematous reactions overlying nevi flammei exist. All of them were observed in children. The description of an eczematous reaction within a congenital nevus flammeus on the left lower leg of a male adult gives reason to discuss this rare phenomenon. Eczema or inflammatory changes within a port-wine stain may mostly be a collision dermatosis with an atopic dermatitis, especially when they arise in children and are localized to the neck and face. When they are observed within a grossly visible vascular malformation, as for example in the Klippel-Trenaunay syndrome, they may have a pathogenesis similar to stasis dermatitis. In rare cases, an eczematous reaction within a nevus flammeus may be the result of genetic mosaicism and is interpreted as a variant of the so-called Meyerson phenomenon.

Unilateral tumid lupus erythematosus

Few cases of inflammatory blaschkolinear dermatoses have been described. We report a case of blaschkolinear cutaneous tumid lupus erythematous and discuss the potential association between cutaneous genetic mosaicism, Blaschko lines and lupus susceptibility.