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At least 37 records · Page 2Linked to original sources
PubMed1979

Lichenoid melanodermatitis. A clinicopathological study of fifty-one Kenyan patients with so-called tropical lichen planus.

Fifty-one Kenyan patients with variable round plaques on the exposed parts, predominantly on the face, and characterized by central hyperpigmentation with annular hypopigmented borders, are described. The clinical and histological picture showed transitions, which ranged from lichen planus and lichenoid poikilodermatous syndromes to dermatitis. This syndrome corresponds largely with (sub-)tropical or actinic lichen planus as reported from the Middle East, where emphasis has been given mainly to a part of the described spectrum of transitions. We suggest that this syndrome should be considered as one of Pinkus' regional lichenoid syndromes which represent hybrids between lichen planus and other conditions rather than as a mere variant of lichen planus.

Adolescent↗
PubMed1977

Contact allergy due to lichens in patients with a history of photosensitivity.

Ten patients with a history of photosensitivity and of a rash showed abnormal reactions to long-wave UVR. The rash occurred particularly in areas exposed to light, though other areas were occasionally involved. The development of the rash could in all patients be related to contact with lichens and although exposure to sunlight usually led to an aggravation of symptoms, some patients, particularly forestry workers, showed exacerbations even during the winter. Positive responses were observed in both irradiated and non-irradiated patch tests with different species of lichen and in several patients irradiation precipitated a stronger response. These findings suggest that lichens can cause both contact and photocontact dermatitis. The suspected allergens contained in these lichens are atranorin, physodalic and pysodic acids.

Adult↗
PubMed1978

Triad of lichen planus, myasthenia gravis, and thymoma.

Myasthenia gravis in a woman was followed by the development of severe erosive lichen planus and thymoma. Lichen planus is not ordinarily associated with other cutaneous or systemic disorders. The reported immunologic findings in some patients with lichen planus and especially the occasional association of lichen planus with certain disorders linked with immunologic disturbances suggest an autoimmune pathogenesis for this disorder.

Female↗
PubMed1977

[Follicular tumidus retro-auricular lichen planus (author's transl)].

Referring to three comparable cases, a new form of lichen planus is described. This form is characterized by a prominent lesion, violaceus in color or pigmented, with white yellowish specks mimicking milia. The histologic picture of lichen follicularis, the presence of typical papules of lichen distant from the retro-auricular lesion make it possible to consider this clinical aspect as a variety of lichen planus.

Adult↗
PubMed1979

HLA antigens in patients with lichen planus.

HLA-ABC antigens were determined in 89 patients with biopsy-confirmed lichen planus, and the HLA antigen frequencies were compared with those in 1967 controls. The younger patients were predominantly male, the older patients predominantly female. No significant association was found between HLA types and lichen planus in this study. A slightly greater incidence of HLA-A3 and B5 antigens was seen, but this increased frequency was not as pronounced as reported by others. When combined, available data on HLA and lichen planus indicate a slightly, but significantly, increased frequency of HLA-A3. None of the HLA antigens known to be associated with insulin-dependent diabetes are associated with lichen planus.

Adolescent↗
PubMed1978

An assessment of vulval lichen sclerosus.

Vulval lichen sclerosus (L.S.) has been assessed clinically, colposcopically, and histologically to ascertain the suitability of including this condition in the nomenclature proposed by the International Society for the Study of Vulval Disease (I.S.S.V.D). In many cases the macroscopic appearance of lichen sclerosus is characteristic, but this is not always the case. Histologically, the appearances of the dermal hyaline change, the reduction in the length and the number of rete pegs, to a lesser extent thinning of the dermis and sometimes thinning of the epidermis are characteristics. The presence of dermal inflammatory cells and changes in the thickness of the keratin layer are, however, much more variable. Exact measurements of the various layers of the vulval skin are not necessary in the routine assessment of lichen sclerosus. The present study justifies the inclusion of lichen sclerosus on histological criteria in the I.S.S.V.D.'s nomenclature.

Female↗
PubMed1976

Lichens as indicators of air pollution.

Field and laboratory studies have demonstrated that lichens are extremely sensitive to sulfur dioxide and that lichens are fairly sensitive to hydrogen fluoride and heavy metals. Further studies are necessary to assess lichens' relative sensitivity to oxidant air pollutants.

Air Pollutants↗
PubMed1977

Smoking habits of 611 patients with oral lichen planus.

The smoking habits of 611 patients (68 per cent females and 32 per cent males) with oral lichen planus were studied. Forty-six per cent were daily smokers, 4 per cent smoked only at social events, and 50 per cent were nonsmokers. In comparison with the nonsmokers, the daily smokers showed significantly lower prevalences of reticular and atrophic types of oral lichen planus lesions and a significantly higher prevelance of the plaque type (P less than 0.001). It is suggested that these findings depend on a mechanism whereby original atrophic and reticular types of lesions are altered into the plaque type of lesions under the influence of smoking. The question arises whether such plaque type of lesion can be regarded as leukoplakias which have been superimposed on the oral mucosa affected by lichen planus.

Adolescent↗
PubMed1979

Changes in carbohydrate expression of lichen planus affected oral epithelial cell membranes.

The purpose of the present study was to examine possible epithelial cell membrane changes in lichen planus affected oral mucosa by the use of the lectins concanavalin-A and ricinus communis agglutinin fraction I. It was shown that these lectins in contrast to what was found in normal epithelium do not bind to the cell membranes of basal cells of lichen planus affected epithelium. The lack of binding of lectins suggests changes in exposed carbohydrates at the surfaces of the cells. The findings may support the hypothesis of antigenic changes in the lichen planus affected epithelium.

Cell Membrane↗
PubMed1975

Coexistence of lichen planus and bullous pemphigoid. A immunopathological study.

A 43-year-old white man presented with a generalized eruption of lichen planus and tense blisters within the lichenoid lesions and also on clinically normal skin. Direct immunofluorescence (IF) studies revealed immunological and histopathological characteristics of lichen planus in the lichenoid lesions and of bullous pemphigoid in the bullous lesions, and indirect IF studies showed that the patient had circulating antibasement membrane antibodies. The coexistence of both disorders may indicate a possible link between the pathology in the junctional zone in lichen planus and the appearance of antibasement membrane zone antibodies and bullous lesions, respectively.

Adult↗
PubMed1976

Glucose-6-phosphate dehydrogenase in lichen planus skin.

The apparent Michaelis constant (Km) for glucose-6-phosphate of the enzyme glucose-6-phosphate dehydrogenase has been measured in extracts prepared from biopsies of normal human skin and from both affected and apparently normal skin of patients with lichen planus. No differences of Km were found and starch gel electrophoresis of extracts from lichen planus lesions and normal controls showed similar patterns when stained for glucose-6-phosphate dehydrogenase activity. These results do not support the view that lichen planus is an inborn error of metabolism in which the structure of glucose-6-phosphate dehydrogenase of skin is affected.

Electrophoresis, Starch Gel↗
PubMed1978

Familial lichen planus. Another disease or a distinct people?

When lichen planus strikes families, a very rare happening, it is likely to afflict younger members, to erupt more acutely, extensively, and gravely, attacking also nails and mucous membranes, and to recur. Ten patients with familial lichen planus, two each from five distinct Caucasian families, the parents of whom were unrelated by birth, were found to be carrying HLA-B7 statistically more frequently than in the normal population or in those with the characteristic forms of lichen planus. We hint that their genotype might have rendered them susceptible to a pathogen that precipitated their disease.

Adolescent↗
PubMedDate not supplied

Lichen planus actinicus.

Two patients with lichen planus actinicus are reported. Lichen planus actinicus is more descriptive than lichen planus tropicus, since the condition appears in more temperate climate, i.e. Italy. The etiology of this condition is obscure, but light may act as a triggering mechanism.

Adult↗
PubMed1978

Mixed lichen planus-lupus erythematosus disease.

Two patients are reported with clinical symptoms of systemic lupus erythematosus associated with centrally ulcerated hypertrophic plaques and lip lesions. Histological findings from various sites were features of both lupus erythematosus and lichen planus. An increase in acid mucopolysaccharides and a thickened basement membrane which were present in some biopsies were interpreted as lupus erythematosus. The deposition of immunoglobulins and fibrinogen seemed to favor lupus erythematosus but these findings may also be seen in lichen planus. Four possible interpretations of the findings are discussed. The term "mixed lichen planus--lupus erythematosus disease" may be appropriate for these patients.

Basement Membrane↗
PubMed1976

The inflammatory infiltrate in lichen planus lesions. An autoradiographic and ultrastructural study.

The labeling index of the infiltrate of oral lichen planus lesions was significantly greater than that of normal mucosa, and its labeling activity redistributed, as determined by in vitro autoradiography. An electron microscopic examination of the infiltrate of lichen planus lesions of oral mucosa and skin supported the concept that the lichen planus infiltrate represents a cell mediated immune response in which T lymphocytes and macrophages are predominant.

Adolescent↗
PubMed1977

Arterial blood pressure in patients with oral lichen planus.

The arterial blood pressure of 121 patients with oral lichen planus was determined using the auscultatory method. These values were then compared with those previously found in a general adult population. No significant difference was found betwween the values of the lichen planus patients and those of the general population. The present investigation does not support the hypothesis of a relationship between lichen planus and hypertension.

Adult↗
PubMed1977

Glucose tolerance in patients with oral lichen planus.

Of 123 patients with oral lichen planus two were known diabetics. The remainder were tested for fasting glucosuria, 113 for fasting blood glucose and 103 also with an oral glucose tolerance test. According to the criteria of WHO, 18 of the 123 patients were diabetics. In most of these patients the oral glucose tolerance test was only slightly abnormal. No decrease of the glucose tolerance with increasing duration of lichen planus was demonstrable. Comparison with two general population studies did not reveal any significant difference between the glucose tolerance of the lichen planus patients and that of the general population samples.

Adult↗
PubMed1977

Immunohistochemical study of lichen planus.

The distribution of IgM and IgG in 20 cases of lichen planus and five cases of non-specific inflammation were studied by the unlabelled antibody-enzyme (PAP) technique. Routine paraffin sections were used. In lichen planus deposits of immunoglobulins were seen in and around epithelial cells, in colloid bodies, at epidermo-dermal junctions, and in some inflammatory cells. All cases examined for IgM and eight out of 13 cases examined for IgG were positive. The peripheral migrating epidermal cells were mostly negative. The application of the PAP technique to skin biopsy and the significance of the findings in lichen planus are discussed.

Adult↗