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PubMedDate not supplied

Indirect immunofluorescence to demonstrate lichen planus specific antigen (LPSA) in lichen planus.

BACKGROUND: Current evidence suggests that lichen planus is an immunological disease. Cytotoxic CD8+ cells in the lesional epidermis recognize a unique antigen called lichen planus specific antigen. This antigen could be demonstrated by indirect immunofluorescence using the patient's serum and autologous lesional skin. AIM: To study indirect immunofluorescence pattern in lichen planus, among Indian patients. METHODS: Twenty-five consecutive patients with the clinical diagnosis of lichen planus were enrolled in the study. Direct immunofluorescence was done in all patients. Indirect immunofluorescence using lesional skin as substrate was done in all 25 patients and five patients with other dermatoses. RESULTS: A specific fluorescence pattern corresponding to the distribution of lichen planus specific antigen was observed in the stratum spinosum and granulosum in 22 (88%) patients. It was absent from other parts of the epidermis, dermis and in patients with other dermatoses. CONCLUSION: Indirect immunofluorescence is a useful adjuvant test in lichen planus, particularly in atypical cases.

Adolescent↗
PubMed1965

Allergy to lichens. Allergic contact dermatitis from usnic acid produced by lichenized fungi.

Two forest workers affected with allergic contact dermatitis, which occurred only during work in forest areas, showed positive patch test reactions to lichens containing usnic acid and to isolated usnic acid. Lichens are plants composed of fungi living in symbiosis with algae. Usnic acid, one of the lichenic acids which accumulates in lichenized fungi, is a monobasic acid with dibenzofuran structure and antibiotic properties. Dibenzofuran is chemically related to furocoumarans. Lichens are plentiful in temperate zone forests and allergy to usnic acid represents some part of the "cedar-poisoning" problem in British Columbia. Geographical distribution of lichens containing usnic acid suggests that allergy to usnic acid will be found to be more common than presently recognized.

Adult↗
PubMed1998

Treatment of lichen planus and lichen nitidus with itraconazole: reports of six cases.

Six patients with either lichen planus or lichen nitidus were treated with itraconazole. Two of four patients with lichen planus experienced complete clearing, and the remainder showed a partial response. Itraconazole, like griseofulvin, may prove to be an alternative treatment worth considering in patients with lichen planus or lichen nitidus who have failed other therapies.

Adult↗
PubMed2000

The distribution of group I introns in lichen algae suggests that lichenization facilitates intron lateral transfer.

The nuclear-encoded small subunit ribosomal DNA gene of many lichen-forming green algae in the genus Trebouxia contains a group I intron at Escherichia coli genic position 1512. We studied the evolutionary history of the 1512 intron in Trebouxia spp. (Trebouxiophyceae) by analyzing intron and "host" cell phylogenies. The host trees were constructed by comparing internal transcribed spacer regions of rDNA. Maximum-likelihood, maximum-parsimony, and distance analyses suggest that the 1512 intron was present in the common ancestor of the green algal classes Trebouxiophyceae, Chlorophyceae, and Ulvophyceae. The 1512 intron, however, was laterally transferred at least three times among later-diverging Trebouxia spp. that form lichen partnerships. Intron secondary structure analyses are consistent with this result. Our results support the hypothesis that lichenization may facilitate 1512 group I intron lateral transfer through the close cell-to-cell contact that occurs between the lichen algal and fungal symbionts in the developing lichen thallus.

Alternative Splicing↗
PubMed1986

Lichen planus and coexisting lupus erythematosus versus lichen planus-like lupus erythematosus. Clinical, histologic, and immunopathologic considerations.

A middle-aged black woman presented initially with painful cutaneous plaques that were located at various sites and that were diagnosed histologically as lichen planus. Standard light microscopic examination showed histopathologic variants of lichen planus. Direct immunofluorescence of a skin lesion had negative results for any of the lupus erythematosus bands but did reveal hyaline bodies in the deep cellular layer of the epidermis and the superficial layer of the dermis. These findings were compatible with either lichen planus or lupus erythematosus. However, both the clinical course of the eruption and the antinuclear antibody tests showed that the immunofluorescent antinuclear antibody pattern of large, speckle-like threads were consistent with lupus erythematosus. Furthermore, the large, speckle-like, thready antinuclear antibody pattern, which has been shown to be a marker for a benign subset of lupus erythematosus, is not seen in lichen planus. Lichen planus--like lupus erythematosus was therefore the more likely diagnosis.

Antibodies, Antinuclear↗
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↗
PubMed1998

Vulvar dermatoses: lichen sclerosus, lichen planus, and vulval dermatitis/lichen simplex chronicus.

In our vulvar specialty clinic at Oxford Radcliffe Hospital (Oxford, UK), dermatoses are frequently seen. A recent survey of new patients showed that lichen sclerosus was the most commonly diagnosed vulvar dermatosis; approximately one third of the women had this disorder. Vulvar dermatitis was observed in 20% to 25% of new patients, but lichen planus was rare. Differences were observed in treatment outcomes for patients with vulvar dermatoses, such as lichen sclerosus and lichen planus, versus those with dermatologic disorders affecting the vulva, such as psoriasis and eczema.

Dermatitis↗
PubMed1998

Lichen planus and lichen sclerosus overlap.

Lichen planus and lichen sclerosus share several common features, including lymphocytic infiltration at the dermal-epidermal junction, clinical involvement of both skin and mucosa, erosive disease of mucosal surfaces, and the occasional occurrence of squamous cell carcinoma at the site of chronic, erosive mucosal lesions. In spite of these similarities, there are remarkably few reports of patients who concurrently have evidence of both diseases. We report a patient who had oral lesions of lichen planus and penile lesions of lichen sclerosus and we review possible mechanisms to explain this association.

Aged↗
PubMed1996

Candida biotypes in patients with oral leukoplakia and lichen planus. Candida biotypes in leukoplakia and lichen planus.

Prevalence of yeasts in 35 leukoplakia and 34 oral lichen planus patients was compared with that observed in persons without oral diseases. Serotype and morphotype were determined on Candida albicans isolates. Yeasts were isolated from the oral cavity specimens of 43.7% of the patients. C. albicans (serotype A) was the predominant species (76% in leukoplakia, 88.2% in lichen planus and 60.8% in healthy persons). Sixteen morphotypes were encountered on malt extract agar, being 732, 733, 734, 753 and 754 the most frequently found. Morphotypes SP1N and SP1Y were the most common on Sabouraud-trypheniltetrazolium agar (68.4% of the isolates from leukoplakia and 73.3% from lichen planus, but only 46.6% of the isolates from healthy oral mucosa showed SP1N morphotype). Presence of oral lesions was associated with a marked reduction in the yeast species and C. albicans biotypes, suggesting that C. albicans and particularly some of its biotypes, show a high potential of adaptation to the changes associated with the development of oral leukoplakia and lichen planus.

Adult↗
PubMed2000

Lichen planopilaris-like changes arising within an epidermal nevus: does this case suggest clues to the etiology of lichen planopilaris?

BACKGROUND: Lichen planopilaris shows a perifollicular lymphocytic infiltrate at the level of infundibulum and the isthmus of the hair bulge resulting in necrotic changes within keratinocytes and eventually hair loss. OBJECTIVE: We present a 14-year-old black male with a history of a raised epidermal lesion on the scalp that was present at birth. Over the past few years, the patient developed gradual hair loss and increased verrucous changes of the skin within the original lesion. Histologic sections of the area showed features consistent with an epidermal nevus peripherally, with a central area showing some features characteristic of those seen in lichen planopilaris. In addition, there was marked hyperkeratosis with increased yeast and bacteria within the follicles. CONCLUSIONS: Initiating factors in lichen planopilaris are not well defined. Overgrowth of microorganisms with hyperkeratosis results in factors that disrupt the immune privilege of the hair follicle, leading to an immunologic reaction that is limited to the follicle and spares surrounding eccrine structures. This case suggests possible mechanisms involved in the induction of lichen planopilaris.

Adolescent↗
PubMed1987

Lichen planus specific antigen and antibodies--in a patient with generalized lichen planus.

A 43-year-old man with generalized lichen planus demonstrated serum antibodies against autologous lesional skin. Indirect immunofluorescence using serum and papular lesional skin revealed a lichen planus specific antigen found only in the granular layer. The specific tissue antigen was not detected in normal skin from this patient, in normal skin from patients with skin disorders other than lichen planus or in skin from normal control persons. When titers of the serum antibodies against lichen planus antigen were examined before and after a successful therapy a positive correlation of the titer could be found in this patient.

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↗
PubMed1998

Coexistence of generalized morphea with hisotological changes in lichen sclerosus et atrophicus and lichen planus.

We reported a 44-year-old Japanese woman with generalized multiple sclerotic plaques, which showed histological findings of morphea. This patient also had an erosive lesion on her mouth; its histological findings were consistent with lichen planus. A sclerotic lesion on her thigh showed the histological findings of lichen sclerosus et atrophicus (LSA). These data suggest that similar etiologic events or closely related pathologic processes are involved in morphea, lichen planus, and LSA.

Adult↗
PubMed2001

Lichen sclerosus et atrophicus affecting the wrists and left ankle and clinically simulating lichen planus.

Lichen sclerosus et atrophicus (LSA) is a disease of unknown etiology, although hereditary, endocrine, and autoimmune factors are known to be involved. Although the anal and genital regions are predominantly affected, 2.5% of patients only present with extragenital lesions--particularly of the trunk, neck, and upper limbs. The wrists, palmoplantar regions, nipples, and face are less commonly involved. The possible relationship between LSA and both lichen planus and localized scleroderma (morphea) has not been clearly established, although in a number of cases, several of these conditions have been found simultaneously. We report the case of a 61-year-old woman with LSA lesions affecting only the wrists and left ankle. The unusual character of this presentation is pointed out, along with its clinical similarity to lichen planus.

Diagnosis, Differential↗
PubMed2004

The potential of the lichen symbiosis to cope with the extreme conditions of outer space II: germination capacity of lichen ascospores in response to simulated space conditions.

Complementary to the already well-studied microorganisms, lichens, symbiotic organisms of the mycobiont (fungi) and the photobiont (algae), were used as "model systems" in which to examine the ecological potential to resist to extreme environments of outer space. Ascospores (sexual propagules of the mycobiont) of the lichens Fulgensia bracteata, Xanthoria elegans and Xanthoria parietina were exposed to selected space-simulating conditions (up to 16 h of space vacuum at 10(-3) Pa and UV radiation at 160 nm < or = lambda < or = 400 nm), while embedded in the lichen fruiting bodies. After exposure, the ascospores were discharged and their viability was tested as germination capacity on different culture media including those containing Mars regolith simulant. It was found that (i) the germination rate on media containing Mars regolith simulant was as high as on other mineral-containing media, (ii) if enclosed in the ascocarps, the ascospores survived the vacuum exposure, the UV-irradiation as well as the combined treatment of vacuum and UV to a high degree. In general, 50 % or more viable spores were recovered, with ascospores of X. elegans showing the highest survival. It is suggested that ascospores inside the ascocarps are well protected by the anatomical structure, the gelatinous layer and the pigments (parietin and carotene) against the space parameters tested.

Ascomycota↗
PubMed1983

Coexisting lichen planus and bullous pemphigoid or lichen planus pemphigoides?

A patient with lichen planus pemphigoides is reported. Initial pathologic and immunopathologic evaluation was consistent with coexisting bullous pemphigoid and lichen planus. However, further immunologic evaluation suggested that the circulating antibody was not directed toward bullous pemphigoid antigen but another basement membrane zone antigen. This finding indicates a need for immunologic re-evaluation of lichen planus pemphigoides.

Adult↗
PubMedDate not supplied

Does hydroxyethyl starch cause lichen planus? Lichen planus in a long-time routine blood donor never exposed to hydroxyethyl starch.

A case of lichen planus attributed to exposure to hydroxyethyl starch has been reported previously. In this report, a case of lichen planus in a healthy blood donor never exposed to hydroxyethyl starch is presented, the statistical incidence of lichen planus in healthy leukapheresis donors is approximated, and a description of the Koebner phenomenon, which could falsely lead to incorrect conclusions regarding cause and effect in this disease, is discussed.

Adult↗
PubMed1997

Phylogeny of lichen- and non-lichen-forming omphalinoid mushrooms and the utility of testing for combinability among multiple data sets.

As an initial step toward developing a model system to study requirements for and consequences of transitions to mutualism, the phylogeny of a group of closely related lichenized and nonlichenized basidiomycetes (Omphalina) was reconstructed. The phylogenetic analyses are based on four data sets representing different regions of the nuclear ribosomal repeat unit (ITS1, 5.8S, ITS2, and 25S) obtained from 30 species of Omphalina and related genera. The resulting phylogenetic trees from each of these four data sets, when analyzed separately, were not identical. Testing for the combinability of these four data sets suggested that they could not be combined in their entirety. The removal of ambiguous alignments and saturated sites was sufficient, after reapplying the combinability test on the pruned data sets, to explain the topological discrepancies. In this process, the first of two complementary tests developed by Rodrigo et al. (1993, N.Z. J. Bot. 31:257-268) to assess whether two data sets are the result of the same phylogenetic history was found to be biased, rejecting the combinability of two data sets even when they are samples of the same phylogenetic history. Combining the four pruned data sets yielded phylogenies that suggest the five lichen-forming species of Omphalina form a monophyletic group. The sister group to this symbiotic clade consists mostly of dark brown Omphalina species intermixed with species from the genera Arrhenia and Phaeothellus. The genera Omphalina and Gerronema are shown to be polyphyletic. The lichen-forming species O. ericetorum and the nonmutualistic species O. velutipes, O. epichysium, and O. sphagnicola are the best candidates for experimental work designed to gain a better understanding of mechanisms involved in symbiotic interactions and the role symbiosis has played in the evolution of fungi.

Agaricales↗