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At least 19 recordsLinked to original sources
PubMed2003

Lichen planus associated with hepatitis C virus: no viral transcripts are found in the lichen planus, and effective therapy for hepatitis C virus does not clear lichen planus.

BACKGROUND: Although hepatitis C virus (HCV) was not discovered until 1989, it was recognized for many years that a viral agent was responsible for many cases of posttransfusion or parenterally transmitted hepatitis. Acute HCV is often relatively mild; however, 70% to 80% of patients with HCV go on to develop chronic liver disease during a prolonged period of up to 40 years, and up to 50% of them may remain relatively asymptomatic during that time. A number of associated cutaneous findings have been reported in up to 15% of these patients including lichen planus-like eruptions (LP). OBJECTIVE: We sought to determine whether viral transcripts were present within the skin of patients with HCV and LP, and if systemic virologic response to interferon alfa and ribavirin correlated with response of the LP. Materials and methods A total of 4 men and 1 woman all presented with cutaneous eruptions of LP, and 1 had oral LP lesions. Cutaneous biopsies were performed on all patients. All patients were found to have chronic HCV. In addition to pathologic examination, immunohistochemical stains for lymphoid markers and reverse-transcriptase polymerase chain reaction for HCV was performed on the biopsy specimens. All patients were treated with interferon alfa and ribavirin. RESULTS: In LP there were scattered eosinophils seen in biopsy specimens of 4 of the 5 patients. The lymphoid infiltrate contained predominantly CD3(+) T cells and scattered KP-1(+) mononuclear cells, without CD20(+) B cells. Approximately one fourth of the T cells failed to mark with CD4. Although all patients were seropositive for HCV RNA at the time of biopsy, we were unable to detect HCV RNA by reverse-transcription polymerase chain reaction in any of the patients. The patients' LP showed an inconsistent response to therapy. CONCLUSION: The virus was not found in the LP lesion using reverse-transcription polymerase chain reaction for HCV. Thus, LP appears to be related to the pattern of immune dysregulation induced by HCV, probably in a host with an underlying susceptibility for autoimmune disease. The combination of interferon alfa and ribavirin may be effective in clearing the virus, but viral response did not correlate with clearing of LP.

Adult↗
PubMed2005

The association between HLA DR, DQ antigens, and vulval lichen sclerosus in the UK: HLA DRB112 and its associated DRB112/DQB10301/04/09/010 haplotype confers susceptibility to vulval lichen sclerosus, and HLA DRB10301/04 and its associated DRB10301/04/DQB10201/02/03 haplotype protects from vulval lichen sclerosus.

Lichen sclerosus (LS) is considered to have an immunogenetic background. Several small studies, using serological typing, have reported that HLA-DR11, DR12, and DQ7 were increased in LS, with DR17 less frequent. This study aimed to validate and detect new HLA-DR and DQ associations with LS in females and its characteristic clinical parameters. The cases, 187 female LS patients, and 354 healthy controls were all UK North Europeans. PCR-sequence specific primers method was applied to genotype the HLA-DR, DQ polymorphisms that correspond to 17 serologically defined DR and seven DQ antigens. Statistical analysis was performed with two-tailed Fisher's exact test with Bonferroni adjustment (p value after Bonferrroni adjustment, Pc). We found increased frequency of DRB1*12 (DR12) (11.2%vs 2.5%, pc < 0.01) and the haplotype DRB1*12/DQB1*0301/04/09/010 (11.2%vs 2.5%, p < 0.001, pc < 0.05), and a lower frequency of DRB1*0301/04 (DR17) (11.8%vs 25.8%, pc < 0.01) and the haplotype DRB1*03/DQB1*02DRB1*0301/DQB1*0201/02/03 (11.2%vs 24.6%, pc < 0.0001) in patients compared with controls. HLA DR and DQ antigens were not associated with time of onset of disease, site of involvement, structural changes of genitals, and response to treatment with potent topical steroids. In conclusion, HLA-DR and DQ antigens or their haplotypes appear to be involved in both susceptibility to and protection from LS.

Adolescent↗
PubMed2001

Winter grazing of reindeer in woodland lichen pasture. Effect of lichen availability on the condition of reindeer.

Winter grazing of semi-domesticated reindeer (Rangifer t. tarandus) was investigated at the woodland lichen pasture (lichen approximately 550kg DMha(-1)) in Kaamanen, northern Finland during the winter 1996-1997. Nine female reindeer mainly dug their food in the snow for 122 days (3 December-4 April) in a fenced area of 36.3ha. Over half of the fenced area was lichen dominated dry pine forest. The amount of lichens in lichen forest inside the fence was estimated before and after grazing. Area of grazed and condition of reindeer as well as snow conditions were monitored. Reindeer grazed over the whole area of lichen forest in early winter but from mid-winter they tended to graze on the areas with the greatest lichen abundancy. The amount of lichens measured decreased in the latter areas by 40% and in the other part of the lichen pasture by 17%, respectively. In both of these areas the residual amounts of lichens left after grazing were similar. Of the dominant lichens, the amount of C. stellaris decreased the most and the amount of Cl. uncialis the least. During the study, the estimated average daily area grazed varied from 4 to 87m(2) per reindeer. It was calculated that individual reindeer obtained 2.6kg of lichen DM per day during the most intensive digging period when the body condition score and weight of reindeer increased. Otherwise, the body condition score and weight decreased. Reindeer finished foraging for ground lichens and started to search for arboreal lichens in mid-March when the snow layer was 70-80cm thick and contained some hard snow layers which lifted reindeer. Both the amount of lichens in the pasture and the snow conditions essentially affect the nutritional status of reindeer in the woodland region during winter. Assuming that a reindeer is able to graze around 30m(2) per day in the snow during mid and late winter, there should be, on the basis of energy demand and grazing behaviour of reindeer as well as the nutritive value of lichen, an estimated 1000kg lichen DMha(-1) available in a good condition woodland lichen pasture.

Journal Article↗
PubMed1989

Bullous lichen planus and lichen planus pemphigoides--clinico-pathological comparisons.

Two patients with lichen planus pemphigoides and two with bullous lichen planus were compared. Lichen planus pemphigoides was clinically distinguished by a more generalized lichen planus, more extensive blistering, the need for systemic corticosteroids and by a longer course. The blister of bullous lichen planus was a subepidermal bulla showing degeneration of the epidermal basal layer and other features of lichen planus, whereas in lichen planus pemphigoides the bulla was similar to that of bullous pemphigoid albeit with rather more neutrophils than are usually seen. Direct immunofluorescence was positive in lichen planus pemphigoides and negative in bullous lichen planus. Lichen planus pemphigoides and bullous lichen planus are separate entities: the former is an auto-immune disease precipitated by lichen planus and not related to bullous pemphigoid, the latter is probably not auto-immune but represents the extreme consequence of the lymphoid infiltrate at the dermo-epidermal junction.

Adult↗
PubMed2003

Analysis of hepatitis C virus (HCV) RNA in the lesions of lichen planus in patients with chronic hepatitis C: detection of anti-genomic- as well as genomic-strand HCV RNAs in lichen planus lesions.

BACKGROUND: Hepatitis C virus (HCV) is a single-strand RNA virus. The association of lichen planus with chronic HCV infection has been reported, as has been cryoglobulinemic purpura, psoriasis, urticaria, and porphyria cutanea tarda. However, the cause of lichen planus is unclear. OBJECTIVES: To investigate whether genomic- and/or anti-genomic-strand HCV RNAs are present in the lichen planus lesions of chronic hepatitis C patients and to elucidate the pathogenesis of lichen planus. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) followed by nested-PCR was carried out to detect HCV RNA using RNA samples from lichen planus lesions of three patients with chronic hepatitis C. Since it is well known that commonly there is relatively dense inflammatory cell infiltration mainly in the upper dermis in lichen planus, the same RT-PCR procedure was performed using RNA from peripheral blood leukocytes from the same patients. In addition, in one patient, the same procedure was also performed using an RNA sample from normal skin. RESULTS: Bands of the appropriate size (161 base pairs corresponding to region 98-258 of HCV RNA) in the nested-PCR products for both genomic- and anti-genomic-strands were detected in lichen planus lesions as well as in peripheral blood leukocytes in all the cases. CONCLUSION: To the best of our knowledge, this is the first report showing the presence of anti-genomic- as well as genomic-strand HCV RNAs in lichen planus lesions in patients with chronic hepatitis C; suggesting that HCV-associated lichen planus lesions may be sites of HCV replication.

Female↗
PubMed1999

Does lichen sclerosus play a central role in the pathogenesis of human papillomavirus negative vulvar squamous cell carcinoma? The itch-scratch-lichen sclerosus hypothesis.

In the past decade, two types of vulvar squamous cell carcinoma (SCC) have been delineated, Human papillomavirus (HPV) positive and negative. Clinicopathologic, virologic, cytomorphometric, and genetic differences support the view that these two types of carcinoma are fundamentally different and that HPV-negative carcinoma is not simply carcinoma where viral DNA has not been able to be identified. The traditional view of HPV-negative carcinoma is that it is caused by chronic tissue damage from itching and scratching. However, itching and scratching alone do not explain the close association of carcinoma with lichen sclerosus, nor the absence of such an association with other itchy conditions such as eczema or psoriasis. These observations point to a role for lichen sclerosus in the pathogenesis of vulvar carcinoma. Most observations about the etiology of lichen sclerosus can be grouped into its immunogenetic or genital predisposition, or the Köbner phenomenon. In the itch-scratch-lichen sclerosus hypothesis, lichen sclerosus is postulated to occur as a Köbner phenomenon in women with the susceptible immunophenotype who scratch because of genital irritants such as urine, vaginal secretions and smegma, and psychological factors. Lichen sclerosus, itself a very itchy condition, contributes to a vicious cycle of itching and scratching which leads to superimposed lichen simplex chronicus, squamous cell hyperplasia, and ultimately carcinoma. The itch-scratch-lichen sclerosus hypothesis reconciles the traditional itch-scratch hypothesis with the strong clinicopathologic association of lichen sclerosus with carcinoma.

Journal Article↗
PubMed1995

Generalized lichen nitidus appearing subsequent to lichen planus.

A 27-year-old man was seen with multiple, small, shiny papules on his shoulders, upper arms, and trunk, and hyperpigmented violaceous plaques on his feet. The former was diagnosed as generalized lichen nitidus and the latter, as lichen planus. It is not likely that the coexistence of the two diseases in this patient is a fortuitous one, since generalized lichen nitidus is a very rare condition. The association of lichen nitidus and lichen planus suggests that lichen nitidus is closely related to lichen planus and that the two diseases may be different manifestations of essentially the same pathogenetic process.

Adult↗
PubMed1986

Toxicity of Iceland lichen and reindeer lichen.

Iceland lichen (Cetraria islandica) is sold in health food stores to prevent various disorders. In olden times it and sometimes also reindeer lichen (Cladonia sp.) have been used as emergency food. Lichen contains bitter and potentially toxic lichen acids and it also concentrates heavy metals. Therefore lichen toxicity was studied with traditional pretreatment methods (boiling, ash-soaking or both). Untreated and only shortly boiled lichens were lethally toxic to mice in 50 and 25% w/w mixtures in food, but when ash-soaking was added mice tolerated Cetraria (but not Cladonia) reasonably well for 3 weeks. In a 3 month test in rats 25% mixture of Cladonia was tolerated well and blood tests were normal at the end. However, urinary protein was increased, the autopsies revealed kidney changes corresponding to a mild heavy metal poisoning, as the lead concentrations in kidney and lichen were high.

Animals↗
PubMed2003

Non-destructive analysis of pigments and other organic compounds in lichens using Fourier-transform Raman spectroscopy: a study of Antarctic epilithic lichens.

Lichens in Antarctic habitats are subjected to environmental extremes, including UVB radiation, desiccation and low temperatures, as well as to rapid fluctuations in these. Lichens synthesise a variety of chemical compounds in response to their environmental conditions which contribute towards their colour, and which act as protectants against physiological stresses. The fluorescence generated by the lichens at 532 nm can be used in epifluorescence microscopy to identify their presence on substrata but this can severely affect the Raman spectra using visible excitation. The advantage of the near infrared excitation used in FT-Raman spectroscopy in minimising fluorescence emission facilitates the molecular characterisation of lichen encrustations without having to remove the thallus from its substrate or remove or otherwise damage any part of the thallus. Spectroscopic biomarkers are proposed which allow the lichens to be characterised by the identification of characteristic lichen substances; the use of these biomarkers for the preliminary taxonomic identification of Antarctic lichens is examined and some potential pitfalls are described.

Antarctic Regions↗
PubMed2000

Lichen planus--specific antigen in oral lichen planus and oral lichenoid drug eruptions.

OBJECTIVE: To investigate the usefulness of lichen planus-specific antigen as a marker to distinguish idiopathic oral lichen planus from oral lichenoid drug eruptions. STUDY DESIGN: Biopsy samples were taken from 6 patients with oral lichenoid drug eruptions and 6 patients with idiopathic oral lichen planus. Each biopsy sample was examined for the presence of lichen planus-specific antigen by using a modification of a previously described immunofluorescence method that uses autologous serum and also allogenic sera from the remaining 11 cases. RESULTS: All autologous and allogenic immunofluorescence tests showed negative findings for lichen planus-specific antigen. CONCLUSIONS: Lichen planus-specific antigen is not a useful marker to distinguish oral lichenoid drug eruptions from idiopathic lichen planus. This finding is in contrast with our findings in an earlier study of basal cell cytoplasmic autoantibodies.

Antigens↗
PubMed1983

Lichen planus dermopathy: demonstration of a lichen planus specific epidermal antigen in affected patients.

Lichen planus is a common papulosquamous disorder of skin and mucous membranes of unknown etiology. Studies reported here demonstrate a lichen planus specific antigen (LPSA) in granular and deep prickle epithelial cells from the lichen planus lesion. Sera from seven out of eight lichen planus patients tested contained an antibody to LPSA. The LPSA was not detected in normal skin tissues from lichen planus patients, or in skin from normal donors and skin from patients with skin disorders other than lichen planus. A serologic survey of serum from people with no clinical history of lichen planus revealed approximately a 7% incidence of antibody to LPSA. These studies suggest that LPSA may be of exogenous origin.

Adolescent↗
PubMed1998

Lichen sclerosus and lichen planus: a spectrum of disease? Report of two cases and review of the literature.

There has long been controversy concerning the relationship between lichen planus and lichen sclerosus. Whilst these two conditions are now considered distinct, there are shared clinical and pathological features. We now describe two patients with the cutaneous involvement of both lichen planus and lichen sclerosus, presenting a review of similar reported cases and discussing the implications for pathogenesis of these two diseases. Neither lichen planus (LP) nor lichen sclerosus (LS) are uncommon yet they have only infrequently been reported as coexisting. In his original description of LS, however, Hallopeau considered it to be a variant of LP and Gougerot has also commented on a possible common pathogenesis for the two conditions. Features which tend to support such as association include the distribution of the cutaneous lesions, histopathological features such as hydropic basal cell degeneration and a band-like lymphohistiocytic infiltrate in the dermis, and the reported association with autoimmune disease. We now report two patients in whom coexistent cutaneous LS and LP was confirmed histologically.

Adult↗
PubMed1992

Immunohistochemical examination of lichen nitidus suggests that it is not a localized papular variant of lichen planus.

BACKGROUND: Lichen nitidus is believed, by some, to be a variant of lichen planus, and by others to be a distinct entity. OBJECTIVE: We examined five cases of lichen nitidus with immunohistochemical reagents designed to characterize the dermal inflammatory infiltrate in an attempt to resolve the uncertainty. METHODS: We stained formalin-fixed, paraffin-embedded tissue sections with the following antibodies: L26, A6, KP1, BerH2, OPD4, and HECA-452. RESULTS: The inflammatory infiltrate was 90% A6+, with few L26+ cells. In contrast to lichen planus, KP1+ macrophages were seen and fewer of the lymphocytes demonstrated HECA-452. Fifty percent to 80% of lymphocytes were OPD4 positive, similar to that usually seen in lichen planus. Rare Ki-1+ cells were seen in one case. CONCLUSION: We believe that the pattern of a mixed cellular infiltrate characterized by macrophages and a helper T cell response with few HECA-452+ cells is somewhat different from the pattern seen in lichen planus, wherein almost all of the cells are CD4+/HECA-452+ lymphocytes. This suggests a different immunologic pathogenesis.

Dermatitis↗
PubMed2001

Hepatitis C virus infection prevalence in lichen planus: examination of lesional and normal skin of hepatitis C virus-infected patients with lichen planus for the presence of hepatitis C virus RNA.

Hepatitis C virus (HCV) is the main cause of parenterally transmitted non-A, non-B viral hepatitis. In recent years, a significant association between lichen planus and chronic HCV infection has been reported. Anti-HCV antibody status was evaluated by ELISA in 54 patients with lichen planus and 54 patients with minor dermatological disorders. PCR was used to examine HCV RNA from serum and lesional and nonlesional cutaneous biopsy samples of HCV-infected patients. Seven patients with lichen planus (12.9%) and two patients in the control group (3.7%) were anti-HCV antibody positive. Five out of seven patients with anti-HCV antibodies had demonstrable HCV RNA in lesional skin biopsies. The viral RNA was absent in three out of four patients with lichen planus whose serum samples were positive for HCV RNA and agreed to biopsy of nonlesional skin. The prevalence of HCV infection is not increased in Turkish patients with lichen planus. However our findings suggest that the virus may play a potential pathogenic role by replicating in cutaneous tissue and triggering lichen planus in genetically susceptible HCV-infected patients.

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↗