Genetic linkage between the collagen type VII gene COL7A1 and pretibial epidermolysis bullosa with lichenoid features.

Pretibial epidermolysis bullosa is a rare form of dominant dystrophic epidermolysis bullosa. The disease was diagnosed after considerable delay in a large Belgian family and was remarkable for its late age at onset and its misleading clinical presentation in the proband, which strongly resembled keratosis lichenoides chronica. Both recessively and dominantly inherited forms of dystrophic epidermolysis bullosa have been shown to be linked to the collagen type VII gene, COL7A1. Two-point linkage analysis with two intragenic polymorphisms (PvuII, AluI) in COL7A1 was performed. Strong genetic linkage between the disease in this family and COL7A1 was demonstrated by a lod score of 4.45 (theta = 0) for the AluI polymorphism. The observed intrafamilial variability of clinical phenotypes contradicts the presently proposed classification of dominantly inherited dystrophic epidermolysis bullosa.

Pseudoxanthoma elasticum: similar autosomal recessive subtype in Belgian and Afrikaner families.

A multidisciplinary survey of the clinical and genetic characteristics of 26 Belgian and 32 Afrikaner families with biopsy-proven pseudoxanthoma elasticum (PXE) was undertaken. The major PXE phenotype emerging from this study is very similar in both patient groups and is characterized by severe ophthalmologic manifestations with variable, mild cutaneous and vascular symptoms. In the families with more than one affected relative, segregation analysis is compatible with autosomal recessive inheritance in both groups. It is suggested that the PXE phenotype of these Belgian and Afrikaner patients is distinct from the other recognized PXE subtypes. The phenotypic resemblance in both patient groups raises the question whether a similar genetic mechanism is involved.

Multiple clear cell acanthomas. A clinical, histological, and ultrastructural report.

A case of multiple clear cell acanthomas in a 64-year-old woman is reported. The clinical and histological findings of this rare entity are consistent with the hypothesis that clear cell acanthomas are benign epidermal tumors. An ultrastructural study was performed with special emphasis on the melanocytic-keratinocytic interaction.

The Bazex-Dupré-Christol syndrome.

BACKGROUND: The Bazex-Dupré-Christol syndrome is characterized by follicular atrophoderma, congenital hypotrichosis, and basal cell neoformations that include basal cell carcinomas and basal cell nevi. OBSERVATIONS: We describe a large family in which 20 persons across four generations present with typical features of the Bazex-Dupré-Christol syndrome. However, the clinical picture in this family differs with regard to gender and age. Male subjects have a uniformly severe disease, whereas female subjects exhibit a range of severity of the syndrome. The most striking difference between male and female subjects is provided by hypotrichosis. In male subjects, hypotrichosis is diffuse and affects all scalp hairs. On the other hand, female subjects do not have hypotrichosis, but normal hairs are intermingled with abnormal hairs. In infancy and childhood, multiple milia are present, whereas in adults only a few milia are observed. CONCLUSIONS: The family pedigree seems to be consistent with an X-linked inheritance, since male-to-male transmission does not occur. Moreover, further evidence of an X-linked dominant mode of inheritance could be derived from the observation of gender differences that can be attributed to the lyonization phenomenon in female subjects. From a clinical and morphologic point of view, the Bazex-Dupré-Christol syndrome seems to be a disorder of the hair follicle.

Morphological changes in the proximal area of the rat's hair follicle during early catagen. An electron-microscopic study.

This electron-microscopic study of the catagen phase shows that the first alteration of regression of the follicle is localized in the papilla, where the cells withdraw their offshoots and break the contact with the basal lamina. Both at the level of the papilla and of the bulb structures appear that increase the cell cohesion. Under the influence of the outer root sheath an upward migration occurs. This is followed by plication and thickening of the basal lamina. The alterations in the connective tissue sheath occur in a further stage. The first signs of autolysis occur in the center of the epithelial column. At the end of the catagen stage macrophages take care of the clearing-up.

Livedo racemosa generalisata and stroke.

The authors describe three young female patients with generalized livedo racemosa and cerebral infarction. The radiologic and biopsy findings point to a widespread vasculopathy, involving small and mid-sized arteries. The histologic examination of the temporal artery biopsy in two patients gives additional evidence for a chronic endarteritis as possible underlying cause of this disease entity.

PIP: This paper presents 3 cases of generalized livedo racemosa and cerebral infarction in female patients ages 27, 39, and 42 years. Livedo racemosa is characterized by a broken, irregular pattern on the skin. It is probably caused by patchy impairment of cutaneous arteriolar circulation, resulting in reflectory venous dilation and stasis of blood. Livedo may accompany diseases such as atherosclerosis, diseases with intravascular occlusion, and collagen disorders, indicating a need for a careful search for an underlying condition. These 3 patients demonstrated several risk factors for atherosclerosis: hypertension (1 patient), oral contraceptive use (2 patients), and smoking (2 patients). The clinical findings in these 3 cases provide support to the theory that a chronic endarteritis obliterans of the small and medium-sized arteries is the underlying cause for the skin and neurologic manifestations in livedo racemosa associated with stroke.

Pharmacokinetics of acitretin.

Acitretin, the metabolite of etretinate, is eliminated far more rapidly from the human body than is etretinate. It has therefore been suggested that only a short period of contraception would be required following the completion of long-term therapy. However, recent studies have demonstrated the presence of etretinate in the plasma of acitretin-treated patients. In this paper, we review the results of studies at our centre in view of the recently discovered metabolic pathways for acitretin. Re-esterification of acitretin to etretinate, however, results in a loss of the metabolic advantages of acitretin. Because of this new knowledge, the recommended contraception period after acitretin therapy has been lengthened to 2 years.

[Dermatology in current medicine]. / Dermatologie in de hedendaagse geneeskunde.

Dermatology evolved in the second part of the last century as a branch of internal medicine and was for many years confined to morphologic descriptions. Skin diseases are common and vary enormously in severity. Although most of the conditions are not life threatening, many of them are debilitating due to functional loss, pain and itch, and the social problems they cause. Skin diseases are a major public health problem in developing countries. After the second world war there has been an explosion both in the amount of scientific knowledge and with regard to the treatment of dermatoses, many of which can now be managed adequately. The dermatologist is also involved in prevention of skin diseases, as e.g. contact dermatitis and malignant tumors of the skin. Increasing specialisation within dermatology has become more common with the expansion of expertise in dermatopathology, photodermatology, contact dermatology, dermatological surgery, dermatologic pediatrics, phlebology. There are too many dermatologists in our country. If an increasing role in caring for minor skin diseases would be assigned to the generalist, the government he will have to decide how contraction of dermatology manpower would occur and how the dermatology training of the generalist should be improved.

Halomethasone (C 48.401-Ba) for the topical treatment of common dermatoses.

C 48.401-Ba cream, containing 0.05% halomethasone was compared in a double-blind between-patients trial with a cream containing 0.1% betamethasone valerate in forty-eight patients suffering from atopic dermatitis and in thirty-nine patients suffering from seborrhoeic dermatitis. A similar comparison was made with ointments containing the same concentration of active ingredient in forty-six patients suffering from atopic dermatitis. Both ointments were also compared in a within-patient double-blind trial in thirty patients suffering from psoriasis. The analysis of the results showed that for the treatment of the above-mentioned dermatoses, both drugs, the cream as well as the ointment, are equally effective and well tolerated.

[Andrews' pustular bacterids of hands and feet; Sachs' acrodermatitis pustulosa perstans. Histological study (author's transl)]. / La pustulose palmo-plantaire chronique et récidivante (pustular bacterids of hands and feet d'Andrews) (acrodermatitis pustulosa perstans de Sachs). Etude histologique.

Pustulosis palmaris et plantaris chronica et recidivans (pustular bacterid of Andrews) is not an exceptional disease. Its characteristic histological structure is to be considered as a major element of the diagnosis. The fully developed pustule is an oval cavity with transverse long axis, entirely situated within a loca-ly hyperplastic epidermis. Its formation goes through several stages. The first one is spongiosis appearing in the epidermis above the top of a dermal papilla. This gives rise to a vesicle filled with fluid and mononuclear leucocytes. In the next stage, the roof consisting of the malpighian layers is disrupted, and the vesicular fluid comes into contact with the horny layer. There is massive invasion of the cavity by polymorphonuclear leucocytes which penetrate into the intercellular spaces of the vesicle wall, where pictures of spongiform pustules are seen. The initial vesicle, and the late, secundary appearance of the spongiform aspects demonstrate that the mechanism of formation of the lesion of pustulosis palmaris et plantaris chronica et recidivans is different from the one of psoriasis pustulosa palmo-plantaris and that, consequently, these are two different diseases.

[Histochemical and ultrastructural study of cytochrome-oxydase in basal cell epithelioma]. / Etude histochimique et ultrastructurale de la cytochrome-oxydase dans l'épithélioma baso-cellulaire

The activity of cytochrome-oxydase is less pronounced in the basal cell epithelioma than in the basal cells of the surrounding normal epidermis. The electron microscopic study of the localisation of the enzyme reveals that the cells of the basal cell epithelioma contain two types of mitochondria, the first of which having the same size as the epidermal mitochondria, and the other being giant mitochondria. The latter seem to be less active. The weak reactivity of the basal cell epithelioma for cytochrome-oxydase is probably due to the reduction of the cristae in mitochondria and to the functional deficiency of the giant mitochondria.

[Congenital diffuse melanosis]. / Mélanose diffuse congénitale.

Two cases of diffuse congenital melanosis are presented. The hyperpigmentation appeared shortly after birth and invades progressively the trunk and the limbs. It is diffuse and most intensive on the abdomen and the back, and reticulated on the neck, the genitals and in the groins. The nails are thin and their surface is slightly irregular. Histologic examination reveals the presence of melanin in the deep and superficial layers of the epidermis. On electron microscopy the melanosomes are not grouped within the keratinocytes, but are dispersed throughout the cytoplasm of the epidermal cells. The disease can be considered as an autonomous entity. The mechanism of the hyperpigmentation is not known.

[Herpes gestationis. A histological and electron microscopic study (author's transl)]. / Herpes gestationis. Etude histologique et ultrastructurale.

The histology and electron microscopy of two cases of herpes gestationis is described (HG). It appears that at the histological as well as at the ultrastructural level, the blister of HG results from degenerative changes in the basal cells and is initially located in the epidermis. It is associated with spongiosis. As a consequence of the disappearance of the basal cell layer, the blister is secondarily found between the malpighian layer and the subepidermal basement membrane. Immunologically, C3 could be found at that dermo-epidermal junction. Although the immunological findings can be similar to those of BP, it is believed that HG and BP must be considered as different entities, because of the very particular clinical features of HG and because the blister formation is different in both diseases.