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At least 19 recordsLinked to original sources
PubMed1977

[Coexistence of lichen planus and bullous pemphigoid (an immunofluorescence study of a "lichen pemphigoides") (author's transl)].

A 35 year old black man presented with a generalized eruption of lichen planus; subsequently tense blisters appeared within the lichenoid lesions and on clinically normal skin. Histopathological characteristics of lichen planus were present in the papules, and those of bullous pemphigoid were seen in the bullae taken from non-lichenoid skin. Direct immunofluorescence studies revealed immunological characteristics of lichen planus in skin and mucosal lesions of L. P. Bound IgG and beta1 C/beta1 A with tubular patterns were detected at the dermo-epidermal junction in all the skin fragments (clinically normal skin, bullous lesions lichenoid skin and mucous lesions). Indirect immunofluorescence studies showed at several intervals that the patient had circulating antibasement membrane zone antibodies (IgG; titres 1/50). This is the third published case in which immunofluorescence studies have established the "pemphigoid" nature of some bullous lichen planus. These findings are in favour of an immune disorder in lichen planus.

Adult↗
PubMed1975

[Lichen ruber planus and lichen ruber verrucosus of the skin: therapeutic results using vitamin A acid in 98 patients].

98 patients, 50 suffering from papular lichen planus of the skin, 48 suffering from hypertrophic lichen planus, were treated systemically or topically with vitamin A acid. In 52 out of the 98 patients, the treatment was started within the first 3 months after the beginning of the disease. The patients with papular lichen planus improved rapidly to systemic vitamin A acid administration. In hypertrophic lichen planus only topical vitamin A acid application showed satisfactory results. The possible side effects of this treatment are mentioned. Patients with disturbed hepatocellular of hepatocystic conditions are unsuitable for vitamin A acid therapy.

Administration, Oral↗
PubMed1977

Cell-mediated immunity in lichen planus. In vitro tests with extracts from lichen planus lesions.

Extracts were prepared from lichen planus lesions and from healthy epidermis of normal controls. Their effect on the migration and lymphocyte transformation of autologous leukocytes was studied. On the whole, the ranges of variation and mean values of the autologous leukocyte migration indices obtained in the presence of LP skin extract or sediment from 10 LP patients did not significantly differ from those recorded in the presence of similar extracts prepared from the epidermis of 12 normal controls. Two assays with LP skin sediment antigen and one assay with LP supernatant antigen, however, fell within the range of significant changes in migration. Lymphocyte transformation, as indicated by increased thymidine uptake, was significantly stimulated by LP epidermis in 1 case of 5 LP patients. Extracts from normal epidermis did not affect the transformation of autologous lymphocytes. The phytohemagglutinin response of lymphocytes from LP patients was the same as that of normal controls. The results do not indicate that cell-mediated immunity toward epidermal antigens play any significant role in the etiopathogenesis of lichen planus.

Adult↗
PubMed1979

Ungual lichen planus. Lichen planus of the nail.

Although reports in the literature are sparse, a definite relationship exists between nail anomalies and lichen planus. Ungual lichen planus may occur without any mucocutaneous signs, as has been documented by histologic studies. It may be the initial and most important clinical manifestation of the disease process, and permanent anonychia may result unless corticosteroid therapy is initiated promptly. Increased awareness of nail involvement will result in a more frequent diagnosis and better understanding of the disorder.

Adrenal Cortex Hormones↗
PubMed1977

[Lichen aureus or lichen purpuricus; about 5 cases; ultrastructural study].

Clinical, histological and ultrastructural features in five cases of lichen aureus are descirbed. This rare condition with ages ranging here from 6 to 31 consists of a pigmented papular and purpuric eruption. Unilaterally, trunk or limb may be involved, in a possible systematized distribution. The microscopic picture is characterized by a dense histiocytic and lymphocytic infiltration in the upper part of the dermis; extravasation of erythrocytes and iron pigment in the histiocytes are often noticed. In fine structure most cells of the dermal infiltrate are histiocytes (or macrophages) with numerous worm-like structures and even typical Langerhans granules in three cases; histiocytic cells; histiocytes are frequently seen in apposition to lymphocytes. In all these cases, no sign of histiocytosis X is found. Classification of lichen aureus in the group of idiopathic pigmented purpuric eruption is proposed.

Adolescent↗
PubMed1979

[Lichen purpuricus (lichen aureus)].

A 14-year old boy developed lesions, which clinically and histopathologically corresponded to the rare condition known under the term of lichen purpuricus seu aureus. The disease can be classified close to purpura pigmentosa progressiva.

Adolescent↗
PubMed1977

Cellular hypersensitivity to oral lichen planus lesions in vitro.

The purpose of the present investigation was to demonstrate in vitro cellular hypersensitivity to oral lichen planus lesions. Twenty oral lichen planus patients and 20 control persons matched by and sex were examined by the leukocyte migration agarose technique with tissue extracts from oral lichen planus lesions, normal oral mucosa and normal human kidney, the two latter extracts serving as control antigens. The female lichen planus patients showed statistically significant (P=0.004) migration inhibition with extracts from oral lichen planus lesions, which supports the hypothesis of cellular hypersensitivity to oral lichen planus lesions. However, the male lichen planus patients did not show any significant reaction. No significant reaction was found with the control antigens. The findings do not exclude the hypothesis of cellular hypersensitivity to oral lichen planus lesions. Furthermore, they do not support the hypothesis of oral lichen planus being an autoimmune disease.

Adult↗
PubMed1976

Lichen planus in India: an appraisal of 441 cases.

An analytical study of 441 patients with lichen planus is presented. Lichen planus occurrence was 76% of conditions seen at this institution. The sex ratio was 3:2. Most patients having the disease were in the 3rd decade of life. Lichen planus vulgaris (common type) was seen in 329 (74%) patients, lichen planus hypertrophicus in 56 (13%), lichen planus actinicus in 33 (7.5%), lichen planus follicularis in 8 (2%), lichen planus atrophicus in 8 (2%) and lichen planus pemphigoides in 7 (1.5%) patients. Mucous membrane involvement was seen in 127 (29%) cases and nail involvement in only 7 (1.5%).

Adolescent↗
PubMed1975

Lichen striatus: a model for the histologic spectrum of lichenoid reactions.

Three phases of lichenoid reactions are defined: 1) the primary phase, 2) the established phase; and 3) the senescent phase. Lichen striatus is characterized by a primary pattern that may be apparent in the epidermis, the hair follicles, and rarely the sweat glands and ducts. Focal areas of established lichenoid reaction, that are indistinguishable from lichen planus, are common. They usually are confined to the tips of elongated rete ridges. Established lichenoid patterns are occasionally present in hair follicles and are indistinguishable from those seen in lichen planopilaris. Eccrine hidradenitis, a feature of lichen striatus, is rarely seen in lichen planus. Lichen planus may be an adaptive epidermal response to a clone of aggressive lymphocytes and, as such, may be a manifestation of auto-immunity. In lichen striatus, senescent lichenoid patterns resemble those seen in lichen nitidus.

Adolescent↗
PubMed1975

Enzyme changes in lichen planus.

Untreated cases of lichen planus have been studied by histochemical techniques. The acid phosphatase reaction in the transitional zone has been quantitatively estimated and compared with the adjacent relatively normal epidermis. It was found that despite a thickened and accentuated granular layer as seen by routine histological methods there was a marked reduction in the intensity of the acid phosphatase reaction. The glucose-6-phosphate dehydrogenase reaction was marked in the upper layers of the epidermis in active lesions of lichen planus. This is similar to psoriasis, but different from normal human epidermis. The suggestion by other authors that lichen planus is an inborn error of metabolism is discussed. The dendritic cells of the epidermis as studied by the ATPase reaction are virtually absent in regions of active lichen planus and the possible significance of this is mentioned. The horny layer gives a dense reaction for phospholipids in lichen planus and this is similar to psoriatic keratin. The significance of this finding is considered.

Acid Phosphatase↗
PubMed1992

A comparative immunological analysis of the oral mucosa in chronic graft-versus-host disease and oral lichen planus.

Oral mucosal biopsies of 12 allogeneic marrow transplant recipients with chronic graft-versus-host disease (GVHD) involving the mouth were compared with biopsies taken before transplantation. They were also compared with biopsies from otherwise healthy patients with oral lichen planus, and with those from a control group of normal individuals. Biopsies from chronic GVHD exhibited a low number of infiltrating T lymphocytes (CD3 cells) compared with those from oral lichen planus, which showed intense cell infiltration (p less than 0.005). The ratio of CD4 to CD8 cells in biopsies taken after the manifestation of chronic GVHD exhibited no consistent variation compared with those taken before transplantation or with biopsies of oral lichen planus. The CD4/CD8 ratio in all groups investigated varied between 4:1 and 6:1. The number of natural killer cells (CD57), was increased in biopsy specimens taken before transplantation compared with the other groups. The frequency of homing receptor, Leu-8 bearing T cells was low in the biopsy specimens of all groups, compared with the corresponding frequency in peripheral blood (10-45 and 60-90%, respectively; p less than 0.001). In the biopsies from chronic GVHD and oral lichen planus the number of lymphocytes with transferrin receptors was increased compared with the pretransplant and control groups. Virtually no infiltrating cells were carrying interleukin-2 receptors (CD25) in any of the groups studied. Langerhans cells (CD1) were more frequently found in the specimens from chronic GVHD and oral lichen planus than in the pretransplant specimens and the control group (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2025

Fungal and algal lichen symbionts show different transcriptional expression patterns in two climate zones.

In the lichen symbiosis, the fungal and algal partners constitute a closely integrated system. The combination of fungal and algal partners changes along climate gradients in many species, and is expected to be adaptive. However, the functional mechanisms behind this symbiosis-mediated environmental adaptation are unknown. We investigated which transcriptional profiles are associated with specific fungal-algal symbiont pairings found in lichens from high-elevation (Lower Supratemperate) and low-elevation (Lower Mesomediterranean) sites at two extremes of a climatic gradient on Mount Limbara, Sardinia. Using laboratory-acclimatized thalli, we found that lichen fungal and algal symbionts show variable expression profiles between high- and low-elevation individuals: circadian- and temperature-associated genes for fungi and light-responsive genes for algae show climate-specific patterns. High- and low-elevation individuals differentially express sugar transporters in both symbionts, pointing to symmetrical and climate-dependent sugar transport mechanisms between them. A light pulse treatment identified asymmetries between fungal and algal light responses, with high- and low-elevation fungal symbionts but only low-elevation algal symbionts showing a response. Together, these results tie previously observed genomic variation along climatic gradients in a lichen species to functional differences in transcription for the fungal and algal symbionts, contributing to our understanding of environmental specialization and niche-specific partner combinations in lichens.

Lichens↗
PubMed1975

The lichen planus-like eruption after bone marrow transplantation.

A lichen planus-like eruption was seen in four patients after bone marrow transplantation. The skin and mucous membrane appearance closely mimicked lichen planus. The histopathology was also very similar to lichen planus. The occurrence of a lichen planus-like eruption (LPLE) after an immune basal cell damage related to the graft-versus-host reaction raised the question of the immune nature of this eruption. The correlation found between biological signs of graft-versus-host reaction and the out-break or relapse of the lichen planus-like eruption supports the hypothesis that the skin changes could be a sign of a chronic immune response against recipient epidermis.

Adolescent↗