Almut Böer

Prurigo pigmentosa: a distinctive inflammatory disease of the skin.

More than 200 patients with prurigo pigmentosa, a disease described first by Nagashima in 1971, have been reported on in Japan, but only 28 non-Japanese patients have come to notice as of today. In order to establish reliable, repeatable criteria for diagnosis of the disease, we studied 25 patients with prurigo pigmentosa and reviewed the literature pertaining to it as recorded in another 182 patients.Clinically, prurigo pigmentosa presents itself as pruritic urticarial papules, papulovesicles, and vesicles arranged in reticular pattern and distributed symmetrically on the back, neck, and chest. Lesions involute in a matter of days, leaving behind netlike pigmentation. Exacerbations and recurrences are the rule. Histopathologically, prurigo pigmentosa begins with a superficial perivascular infiltrate of neutrophils. Shortly thereafter, neutrophils are scattered in dermal papillae and then sweep rapidly through an epidermis in which spongiosis, ballooning, and necrotic keratocytes are accompaniments. En route, abscesses may form in the surface epithelium. Very soon, eosinophils and lymphocytes come to predominate over neutrophils in a dermal infiltrate that assumes a patchy lichenoid pattern. Intraepidermal vesiculation follows on spongiosis and ballooning and, sometimes, subepidermal vesiculation on vacuolar alteration at the dermo-epidermal junction. As the epidermis becomes hyperplastic, parakeratotic, and slightly hyperpigmented, melanophages begin to appear in the dermis. Studies by immunofluorescence are negative invariably. Dapsone or minocyclin are effective treatments; both of those agents inhibit migration and/or function of neutrophils. The cause and pathogenesis have yet to be determined. Prurigo pigmentosa is unique among inflammatory diseases of the skin and the singularity of it is manifest both clinically and histopathologically.

Alopecia mucinosa is mycosis fungoides.

Confusion abounds regarding the terms “follicular mucinosis” and “alopecia mucinosa,” not only concerning definition and essential character, but of relationships between themselves on one hand and between themselves and mycosis fungoides on the other. We address here those issues in methodical fashion, first in historical perspective by review, scrupulously and critically, of what has been said in the many articles devoted to the subject; we next tell how the terms “alopecia mucinosa” and “follicular mucinosis” came to be and how they are employed currently; we then set forth our own observations pertinent to clinical, histopathologic, and biologic aspects of the condition called, conventionally, “alopecia mucinosa,” those observations based on our own findings in sections of tissue cut from 54 biopsy specimens taken from 45 patients, all of them having been signed out previously as “follicular mucinosis;” we proceed to forge clinico-pathologic correlation of lesions in 14 of those 45 patients, utilizing assessments, by examination grossly and microscopically, of attributes in the very same lesion. Last, we propose a concept, and a terminology that derives from it, that synthesizes all that is known now about “alopecia mucinosa” and “follicular mucinosis,” in particular the relationship of “alopecia mucinosa” to mycosis fungoides, including “follicular,” “syringotropic,” and erythrodermic manifestations of it. In short, we affirm that so-called alopecia mucinosa is but one of many morphologic manifestations of mycosis fungoides.

Use of fumaric acid esters in psoriasis

Fumaric acid esters (FAE) are chemical compounds derived from the unsaturated dicarbonic acid fumaric acid. The usage of FAEs in treatment of psoriasis was introduced in the late 1950s. In the 1980s more standardized oral preparations of FAEs were developed containing dimethylfumarate (DMF) and salts of monoethylfumarate (MEF) as main compounds. In 1994, Fumaderm an enteric-coated tablet containing DMF and calcium, magnesium and zinc salts of MEF was approved for the treatment of psoriasis in Germany and since then has become the most commonly used systemic therapy in this country. Fumaric acids have been proven to be an effective therapy in patients with psoriasis even though the mechanisms of action are not completely understood. About 50-70% of the patients achieve PASI 75 improvement within four months of treatment and without any long-term toxicity, immunosuppressive effects or increased risk of infection or malignancy. Tolerance is limited by gastrointestinal side effects and flushing of the skin. This article reviews pharmacokinetics, uses, contraindications, dosages and side effects of treatment with FAEs.

Prurigo pigmentosa is distinctive histopathologically

Dear Sir, In the May 2002 issue of the International Journal of Dermatology (41: 288–291: Prurigo pigmentosa), Gür-Toy et al . reported on two patients with typical clinical features of prurigo pigmentosa, one of whose lesions responded favorably to minocyclin and the other to doxycyclin. In regard to the findings histopathologically, the authors stated that changes of prurigo pigmentosa are nonspecific, consisting of hyperkeratosis, acanthosis, vacuolar alteration, dyskeratotic cells, spongiosis, exocytosis, and a perivascular infiltrate of mononuclear cells. Had the histopathologic findings detailed in some articles devoted to prurigo pigmentosa been included in the review by Gür-Toy et al. , what was deemed by them to be ‘nonspecific’ would have been considered “specific”. 1–4

Keratosis Lichenoides Chronica: Proposal of a Concept

It has been a subject of controversy whether keratosis lichenoides chronica (KLC) is a distinctive inflammatory disease of the skin or whether it represents a manifestation of another well-known disease, such as lichen planus, lupus erythematosus, or lichen simplex chronicus. In search of clear criteria for diagnosis of KLC the entire literature pertinent to the subject was studied and findings clinical and histopathologic as they were telegraphed in them were compared with a patient of my own experience. Review of the literature reveals more than 60 patients in whom the diagnosis of KLC was made. Three categories emerge based on whether the findings presented in a particular article (1) do not permit any diagnosis to be rendered; (2) do allow a diagnosis specific to be made, such as of lichen simplex, lichen planus, or lupus erythematosus; or (3) do not correspond to any disease well defined, such as lichen simplex, lichen planus, lupus erythematosus, but seem to show attributes morphologic, clinically and histopathologically, that are repeatable. Patients diagnosed as having KLC obviously represent a potpourri of different diseases, the most common of them being lichen simplex chronicus, lichen planus, and lupus erythematosus. Fewer than 25 patients reported on, however, presented themselves with lesions very similar to one another clinically, namely, an eruption that involved the face in a manner reminiscent of seborrheic dermatitis and with tiny papules on the trunk and extremities, which assumed linear and reticulate shapes by way of confluence of lesions. Individual papules were infundibulocentric and acrosyringocentric. Findings histopathologic were those of a lichenoid interface dermatitis affiliated with numerous necrotic keratocytes and covered by parakeratosis housing neutrophils in staggered fashion. These patients seem to have an authentic and distinctive condition that is exceedingly rare. In conclusion, the diagnosis of KLC should be made only for patients who present themselves with features clinical and findings histopathologic that resemble closely those of what is summarized in this article under category 3.

Eosinophilic pustular folliculitis in infancy: not a distinctive inflammatory disease of the skin.

In the standard literature of dermatology and dermatopathology “eosinophilic pustular folliculitis in infancy” is presented as a distinctive inflammatory disease of the skin, to wit, a variant of “Ofujis eosinophilic folliculitis”. Assessment critically of the first publication devoted to the subject revealed a potpourri of findings clinical and histopathologic, with no clear criteria being set forth by the authors to enable diagnosis, with precision. Our review of all articles dedicated to the matter of “eosinophilic pustular folliculitis in infancy” shows that criteria for diagnosis are found with great difficulty. The majority of patients reported on had neither “eosinophilic folliculitis,” nor did they present themselves clinically in any way similar to what was originally described by Ofuji. The findings histopathologic told of most commonly were dense and diffuse infiltrates in the dermis that contained many eosinophils, sometimes with periadnexal distribution. We think that the findings reported on in several articles suggest that the patients more likely had a variety of different diseases, among them scabies, insect bites, impetigenized nummular dermatitis, and linear IgA-dermatosis. For clarification of terminology, we suggest that “eosinophilic folliculitis” is better defined as a pattern histopathologic than as a distinctive disease entity. It may be encountered in a variety of conditions (eg, Ofujis disease, arthropod bites, scabies, or dermatophytosis). In sum, no clear criteria have been established for diagnosis of “eosinophilic pustular folliculitis of infancy” and there is no convincing evidence, at present, that “eosinophilic pustular folliculitis of infancy” qualifies as a distinctive inflammatory disease of the skin.

Spectrum of follicular and sebaceous differentiation induced by dermatofibroma.

Background:The term “induction” has been used to designate epidermal changes above dermatofibroma. Whereas follicular differentiation has been reported frequently, sebaceous hyperplasia above dermatofibroma is considered a rarity. Objective:To characterize all changes overlying dermatofibroma and to determine their frequency. Methods:Sections cut from 210 consecutive examples of dermatofibroma were stained with hematoxylin and eosin and analyzed for the presence or absence of induction, for the type of change induced, and for features associated with these findings. Results:The epidermis above dermatofibromas was acanthotic, simulating seborrheic keratosis in 62.9% of the cases, and areas of clear and pale cells similar to those of clear cell acanthoma were seen in 18.6%. Induction of adnexal differentiation was encountered in 41% of the cases. Follicular differentiation was seen in 10.9%, all of which showed some follicular germinative cells. In 9.5%, follicular germinative cells were present together with well-circumscribed mesenchymal papillae. In 4%, formation of a complete hair follicle was encountered. In 16.7% of the dermatofibromas, induction of sebaceous lobules was encountered, whereas sebaceous differentiation in the form of mantles was seen in 25.7% of the cases. Not uncommonly, sebaceous structures were arranged in a reticulate pattern similar to that seen in reticulated acanthoma with sebaceous differentiation (12%). Conclusions:Induction of adnexal structures is more common than currently perceived. Especially, induction of immature and mature sebaceous structures seems to be underrecognized.

Transverse sections for diagnosis of alopecia

Several authors have claimed usage of sections cut horizontally as being preferable to conventional cuts in vertical direction in the diagnosis of alopecias. In this article, we address in critical fashion, all statements that have been made in the literature that seem to favor sections cut horizontally in contrast to sections cut conventionally (ie, vertically) in coming to a diagnosis of diseases of the scalp. Our assessment reveals that the idea of horizontal sections being advantageous compared with sections cut vertically is based largely on the assumption that counting of follicles is the key to a diagnosis with specificity of diseases of the scalp. But a quantitative approach to diagnosis of alopecias is flawed; it does not allow differential diagnosis of common alopecias to be made with certainty. A qualitative approach, however, based on reliable and repeatable criteria applied in sections cut vertically, allows in most instances a diagnosis to be rendered precisely.

Multiple agminated Spitz nevi arising on a café au lait macule: review of the literature with contribution of another case.

The majority of Spitz nevi are acquired solitary lesions. Multiple Spitz nevi are rare and may develop on hyperpigmented skin. We report a 16‐year‐old girl with multiple Spitz nevi arranged on a café au lait macule. Immunohistochemistry showed positivity for S‐100 and HMB‐45. Of interest, expression of Polo‐like kinase (PLK), a novel proliferation marker that recently proved to be positive in up to 98% of malignant melanoma cells, showed positivity in 40% of the nevus cells. The clinical development of multiple Spitz nevi is not yet clear, as they are preferentially excised. Reviewing 70 cases in the literature we found that multiple agminated Spitz nevi occur more frequently than reported previously. In about one‐third of these cases Spitz nevi arose on congenitally hyperpigmented skin.

Histopathologic study of scalp psoriasis: peculiar features including sebaceous gland atrophy.

In a study on scalp psoriasis of 19 patients (11 males and 8 females, 15-64 years of age, psoriasis area severity index partial score of the head ranging from 0.5 to 2.8), we came to notice that, apart from the classical criteria for the diagnosis of psoriasis which were present in all cases, in a majority of patients, sebaceous glands were extremely reduced in size. We compared findings of follicular counts and sebaceous glands with a nonpsoriatic group of individuals (n = 26). Ten cases from the psoriatic population presented with completely atrophic glands, most of the time intermingled with larger glands (P = 0.03); not a single case showed sebaceous gland atrophy in the control group. There were no statistical differences regarding total number of hair follicles (P = 0.08), terminal follicles (P = 0.15), vellus follicles (P = 0.39), and telogen follicles (P = 0.58) between the groups. Other unusual features observed in the scalp psoriasis group were dilation of infundibula in 11 cases, a papillomatous epidermal surface in 8 specimens, parakeratosis at the lips of infundibular ostia in 8 specimens, mitotic figures in 7 cases, and necrotic keratinocytes in 14 cases. We conclude that psoriasis of the scalp may present itself with unexpected microscopic findings, among them being atrophy of sebaceous glands. Further studies are necessary to clarify why this atrophy develops and if it is specific to psoriasis.