Morphometric and ultrastructural analyses of melanocytes, nevus cells, and melanoma cells.

Cytological atypia, revealed in the course of routine light microscopy, is considered a valuable indicator of malignancy in melanocytic lesions. A clear definition of the term cytological atypia, however, is lacking. Therefore, by morphometric analysis of ultrathin sections of 11 malignant melanomas (7 invasive, 3 in situ, and 1 lentigo maligna melanoma) and 10 compound nevi, we evaluated the discriminating power of the various facets of cytological atypia, i.e., nuclear area, area of the nucleolus, area of the total cell, and nuclear irregularity. In each case, at least 50 intraepidermal melanocytic cells were examined. The two-sided U-test showed significant differences between intraepidermal nevus and melanoma cells, with regard to the mean values (mean) and standard deviations (s) of the nuclear area (mean and s, p = 0.00011), area of the nucleolus (mean, p = 0.00043; s, p = 0.00011), and area of the total cell (mean, p = 0.00011; s, p = 0.00093). However, only the mean values and standard deviations of the nuclear area allowed a clear distinction in each individual case. The area of the nucleus can be estimated in the course of routine histology. We therefore think that the size and variation of the nuclear area should be considered in the histological differential diagnosis between malignant melanomas and benign nevi.

Early persistent UVA-pigmentation: ultrastructural and morphometric analyses.

UV-A-induced skin pigmentation was investigated morphologically in semithin and thin sections from 11 volunteers, using different irradiation modalities (single doses of 10, 50 and 100 J/cm2). Visible skin pigmentation was observed in all but two probands, and erythema in two; pronounced pigmentation was present after repeated irradiation only. Contralateral non-irradiated, UV-B-irradiated and suntanned skin specimens UV-B-irradiated and suntanned skin specimens were used as controls. There was an increase in the number of clear cells in the basal layer (x1.6) and particularly of large clear cells (x1.7) after repeated irradiation. Also, the number of melanosomes in melanocytic dendrites (x2.8) increased after repeated irradiation. The number, size and shape of the melanosome complexes in both basal and suprabasal keratinocytes remained unchanged, even when a distinction was made between central and peripheral location. In contrast, suntanned skin showed an increase in melanosome complexes in basal (x5.8) and suprabasal (x3.7) keratinocytes. It is concluded that UV-A-induced skin pigmentation differs in some ways from UV-B or sun-induced melanogenesis, and that the clinical grade of tanning cannot accurately be determined by ultrastructural methods.

[Histiocytosis X. An oligosymptomatic form of Hand-Schüller-Christian disease with a new form and possibilities of diagnosis]. / Histiozytosis X. Eine oligosymptomatische Form des M. Hand-Schüller-Christian mit einer neuen Form und Möglichkeit der Diagnostik.

A patient is reported who had a monosymptomatic, cutaneous form of histiocytosis X. The reactivity of cutaneous histiocytosis-X cells with monoclonal anti-T-6 antibody is discussed as a new diagnostic procedure.

[Epizootic disease caused by the mite Dermanyssus gallinae (De Geer 1778)]. / Epizootie durch die Milbe Dermanyssus gallinae (De Geer 1778).

Having removed a pigeon's nest, a 20-year-old woman developed pruritic skin lesions due to infestation by the mite Dermanyssus gallinae (De Geer 1778). Parasites from inside the nest are demonstrated by light microscope and by scanning electron microscope. As many mite species may infest humans temporarily, such parasites should be considered a possible cause in pruritic dermatoses with unclear origin.

Pityriasis rubra pilaris: a clinico-pathological and therapeutic study with special reference to histochemistry, autoradiography, and electron microscopy.

Five patients with pityriasis rubra pilaris (PRP) were analyzed by means of light and electron microscopy as well as by histochemistry and autoradiography. The results were compared with findings in psoriasis vulgaris. In PRP we found a moderate increase of the labeling index of epidermal cells, a highly increased labeling index of dermal infiltrating cells, and a mild spongiosis, and in the stratum granulosum, a decreased number of tonofilaments and an increased number of keratinosomes. The horny layer in PRP showed a pronounced histochemical and electron microscopical parakeratosis, even when histological parakeratosis was absent. In contrast with psoriasis vulgaris, there was no exocytosis of polymorphonuclear leucocytes into the epidermis, the papillomatosis index was normal, and there were no tortuous capillaries in the dermal papillae. The stratum granulosum was always present and sometimes thickened, showing electron microscopical changes different from those referred to in psoriasis. These changes point to a relatively distinct pattern of epidermal changes in PRP.

[A syndrome: uncombable hair. Observation of 6 members of a family with pili canaliculi, associated with pili torti, progressive alopecia, atopic eczema and hamartomas]. / Zum Syndrom: Unkämmbare Haare. Beobachtung von sechs Mitgliedern einer Familie mit Pili canaliculi, verbunden mit Pili torti, progredienter Alopezie, atopischem Ekzem und Hamartomen.

Six members of one family showed the typical clinical picture of uncombable hair (cheveux incoiffables), a syndrome first described by Dupré, Rochiccioli and Bonafé in 1973. In all six cases scanning electron microscopical investigations revealed characteristic morphological hair changes including longitudinal grooves as well as angular or kidney-shaped patterns in cross sections. Genetically the abnormality seems to be of autosomal dominant heredity with incomplete penetrance. In addition to uncombable hair some of our patients showed pili torti, progressive alopecia areata and atopic eczema. Possible relations of this syndrome with other diseases as pili torti, kinky hair disease or hypotrichia congenita are discussed.

[Ixodes ricinus under the scanning electron microscope]. / Ixodes ricinus im Rasterelektronenmikroskop.

The tick Ixodes ricinus was examined with a scanning electron microscope. The morphology of the mouth parts explains the well known tight attachment of the head of the tick in the skin. Diseases following tick bites and the possibilities of removing the ticks are discussed.

[Hypertrichosis caused by minoxidil]. / Hypertrichose durch Minoxidil.

Minoxidil (6-amino-1,2-dihydro-1-hydroxy-2-imino-4-piperidinopyrimidine), a new substance for the treatment of severe hypertension, is frequently associated with hypertrichosis. This side effect may spontaneously disappear despite continuation of minoxidil-treatment, as it is demonstrated in this case-report.

[Disseminated circumscribed acleroderma associated with diffuse scleroderma of an acrosclerotic type]. / Disseminierte zirkumskripte Sklerodermie und diffuse Sklerodermie vom Typ der Akrosklerodermie.

A case of disseminated, circumscribed scleroderma with diffuse scleroderma of the acrosclerotic type is reported. The relationship between circumscribed and diffuse scleroderma is discussed. Obstructive changes of peripheral vessels are an early feature of scleroderma.

[Onychomycosis: experiences with atraumatic nail avulsion]. / Onychomykose: Erfahrungen mit atraumatischer Nagelentfernung.

Patients with onychomycosis (tinea) of finger- and toenails underwent combined treatment: avulsion of nail plate, local antimycotic and systemic griseofulvin treatment. Avulsion of the involved nails was performed by the patients themselves chemo-mechanically using 50% KI-ointment. 1,500 nails were successfully removed. Out of 250 patients 101 were clinically and mycologically cured after a median delay of 6.5 months. Only 50% of the 101 patients remained cured up to one year after cessation of therapy. Atraumatic nail avulsion in combination with chemotherapy is a reliable, inexpensive, painless, and effective alternative method to surgical excision treating onychomycosis.

Pagetoid reticulosis. A further case report with a review of the literature.

A further case of pagetoid reticulosis (PR) was studied, and the findings were compared with 18 previous case reports in the literature. There seem to be two variants: The generalized type (Ketron-Goodman) with disseminated lesions and a poor prognosis, and the localized type (Woringer-Kolopp), with a single lesion usually located on the extremities with a good prognosis (if the lesion can be totally cleared by excision or highdose-radiation). The basic criterion of diagnosis is a very strong cellular infiltrate within the epidermis, but usually weak in the upper dermis. The etiology of PR remains unclear: In some cases a T-cell lymphoma seems a likely interpretation. In others, epidermal infiltrating cells are not typically lymphoid, but remain morphologically unclassifiable.