Oral diseases associated with hepatitis C virus infection. Part 2: lichen planus and other diseases

Characterization of Mucosal-Associated Invariant T Cells in Oral Lichen Planus

Oral lichen planus (OLP) is an inflammatory condition of unknown cause that has been associated with concurrent candidal infection. Mucosal-associated invariant T (MAIT) cells express the T cell receptor TCRVα7.2 and are activated by riboflavin intermediates produced by microbes. The interaction between MAIT cells, Candida, and OLP is unknown. This study aimed to determine mucosal-associated T cell presence in OLP and whether the abundance of these cells changed due to the presence of either Candida or symptoms, using multiplex immunohistochemistry (mIHC). Ninety formalin fixed-paraffin-embedded (FFPE) tissue samples were assessed using mIHC for the cellular markers CD3, interleukin 18 receptor one (IL18R1), TCRVα7.2, CD161, CD8, and major histocompatibility complex class I-related (MR-1) protein. The samples were stratified into five groups on the basis of clinical (presence/absence of symptoms) and microbiological (presence/absence of Candida) criteria. Results demonstrated the presence of MAIT cell phenotypes in OLP inflammatory infiltrate within the connective tissue. Significant differences existed between different OLP groups with the percentage of log(CD3+ CD161+) and log(CD3+ TCRVα7.2+) positive cells (p < 0.001 and p = 0.005 respectively). Significant differences also existed with the relative abundance of triple-stained log(CD3+ CD161+ IL18R1+) cells (p = 0.004). A reduction in log(CD3+ CD161+ IL18R1+) cells was observed in lesional tissue of patients with symptomatic OLP with and without Candida when compared to controls. When present in OLP, MAIT cells were identified within the connective tissue. This study demonstrates that mIHC can be used to identify MAIT cell phenotypes in OLP. Reduced percentage of log(CD3+ CD161+ IL18R1+) cells seen in symptomatic OLP with and without Candida suggests a role for these cells in OLP pathogenesis.

A catalog of 48,425 nonredundant viruses from oral metagenomes expands the horizon of the human oral virome

The human oral cavity is a hotspot of numerous, mostly unexplored, viruses that are important for maintaining oral health and microbiome homeostasis. Here, we analyzed 2,792 publicly available oral metagenomes and proposed the Oral Virus Database (OVD) comprising 48,425 nonredundant viral genomes (≥5 kbp). The OVD catalog substantially expanded the known phylogenetic diversity and host specificity of oral viruses, allowing for enhanced delineation of some underrepresented groups such as the predicted Saccharibacteria phages and jumbo viruses. Comparisons of the viral diversity and abundance of different oral cavity habitats suggested strong niche specialization of viromes within individuals. The virome variations in relation to host geography and properties were further uncovered, especially the age-dependent viral compositional signatures in saliva. Overall, the viral genome catalog describes the architecture and variability of the human oral virome, while offering new resources and insights for current and future studies.

The role of dentists in controlling hepatocellular carcinoma in Japan (Review)

In Japan, the method of treatment for hepatitis is well established due to the high rates of hepatitis C. However, the identification of patients with hepatitis who do not receive appropriate treatment poses a major problem. Some patients with this disease may need to consult with a dentist due to the development of extrahepatic manifestations, such as lichen planus, in the oral cavity. Alternatively, the dentist might discover patients with untreated hepatitis C and hepatitis B during routine dental examination. In such cases, the patient should be referred to a hepatologist for further examinations and treatment. Thus, dentists are required to act as 'gatekeepers of hepatitis'. Furthermore, Japanese dentists need to increase hepatitis B vaccine coverage for infection control. By acting as a 'care coordinator of hepatitis', the dentist will be able to contribute to the eradication of liver cancer in Japan, thereby eliminating the discrimination and prejudice against patients with hepatitis. Dentists need to have a deep understanding of liver disease from the viewpoints of both nosocomial infection control and treatment of oral diseases.

Lichen Planus and Hepatitis C Virus Infection: A clinical Evaluation of 168 Cases

Introduction. Hepatitis C virus (HCV) infection is one of the factors which can lead to a chronic liver disease and hepatocellular carcinoma. There have been several reports on the association of oral lichen planus with hepatic disorders, i.e. hepatitis C infection in particular. Considering the controversies about the association of lichen planus with HCV infection on one hand and considerable impact of hepatitis C on the occurrence of chronic liver disease on the other hand, we investigated the association between lichen planus and HCV infection in Sanandaj City. Methods. This cross sectional study included 168 patients with lichen planus, who were referred to the Dermatology Clinic of Besat Hospital between 2014 and 2016. The diagnosis of lichen planus was made by our dermatologist and HCV antibody titer was determined for every patient. Results. Mean age of the patients was 39.7±13.3 years and mean duration of the disease was 14.8 months. 107 (63.7%) patients were men. The highest frequency of lichen planus was recorded in the housewives (30.4%). In 52 (31%) patients the genital area was involved and it was the most common site. In 6 (3.6%) patients the oral mucosa was involved and it was the least common site in our study. Only 4 (2.7%) patients had family history of lichen planus. None of 168 patients included in this study was found to have HCV infection. Conclusion. In this study, we found no relationship between lichen planus and HCV infection. Yet, the exact mechanism underlying the occurrence of lichen planus in the patients with HCV infection has not been determined. Therefore more studies on this subject are recommended.

Potential pathogenic mechanisms involved in the association between lichen planus and hepatitis C virus infection

Lichen planus (LP) is an immune-mediated inflammatory disease that particularly affects the skin and mucous membranes. Its etiology remains elusive, however some trigger factors, including viral or bacterial antigens, drugs and metals, have been postulated. There is a higher prevalence of hepatitis C virus (HCV) infection among patients with LP, with some geographical variations. HCV is an enveloped RNA virus that belongs to the Flaviviridae family and in most instances causes chronic liver infections. It has been hypothesized that HCV may contribute to LP development, but the link between the two disorders is not fully understood. It is still debatable whether HCV leads to the occurrence of LP lesions directly by replication inside the infected cells or indirectly by activating immunological pathways. Molecular studies have revealed HCV RNA in specimens collected from patients with LP. The autoimmune theory was also suggested given that several studies have revealed viral replication and immune response activation associated with autoantibody synthesis. The aim of this review is to summarize the main potential mechanisms involved in the association between LP and HCV infection. Understanding the link between the two disorders may shed some light on the pathogenesis of LP, which is a challenging issue.

Exacerbations of oral lichen planus and elevated levels of aminotransferases

BACKGROUND

Liver enzymes appear to be involved in oral lichen planus (OLP), but it is not known whether the elevation develops concomitantly with exacerbations of disease. We compared the levels of serum hepatic aspartate (AST) and alanine (ALT) aminotransferases as markers of OLP exacerbation in patients with chronic hepatitis C from those with chronic liver disorders, seronegative for hepatitis C virus (HCV).

METHODS

We studied 71 patients with OLP, (48 HCV seropositive and 23 HCV seronegative with chronic liver diseases) measuring AST and ALT. Association of HCV infection status with serum aminotransferase levels in relation to several types of OLP, exacerbations, and clinical score was studied by means of logistic and linear regression (correcting for age and sex).

RESULTS

Of 476 patients screened, 71 were eligible for the study. Patients in the HCV seropositive group had more elevation of AST and ALT levels (mean level, 51.0 U/l; normal level, <45) than patients in the HCV seronegative group (mean level, 47.5 U/l). Mean serum AST and ALT exceeded the upper limit of the normal range in 33 of 48 (68.8%) in the HCV antibody-positive group and in 9 of 23 (39.5%) in the HCV antibody-negative group. Exacerbations of OLP were more frequent in the high-level AST and ALT group, while HCV status group played a minor role.

CONCLUSIONS

Among patients with OLP, mild elevation in aminotransferase levels was more common in patients infected with HCV. AST and ALT concentrations were elevated in association with exacerbation of OLP.

Global epidemiology and burden of HCV infection and HCV-related disease

Chronic HCV infection is a global health problem that affects >184 million people worldwide. HCV is associated with several hepatic and extrahepatic disorders, including several malignancies. The burden of HCV-related disorders is influenced by the number of new and existing cases, number of existing cases and the natural history of the infection. The natural history of HCV is affected by several demographic, virological, clinical and lifestyle factors. Major variations exist in the burden of HCV among different populations and geographical regions, as well as over time. With the advent of new and efficacious antiviral treatments, it is important to learn the determinants of HCV burden to design appropriate strategies for detection, prognostication and treatment. Furthermore, with the expected growth of patients cured of HCV, it is essential to learn about the possible change in natural history and burden of disease in these patients. In this Review, we will discuss the global epidemiology and burden of HCV and its complications, as well as the natural history and clinical course of chronic and cured HCV infection.

Cutaneous manifestations in disorders of hepatobiliary system

BACKGROUND

Hepatobiliary diseases are associated with various mucocutaneous changes that are directly and indirectly associated with these diseases. There is a dearth of studies from India dealing with cutaneous manifestations in liver disorders.

AIM

This study was conducted to know the spectrum of cutaneous changes and their correlation with liver function tests in patients with disorders of hepatobiliary system.

METHODS

This was a descriptive study conducted among in patients and outpatients with primary hepatobiliary disorders at a tertiary care center in South India. Detailed history taking and examination was done. Visual analog score (VAS) and 5D itch score was employed to quantify pruritus. Correlation of liver function tests with pruritus and comparison of skin changes in the major disease groups was attempted.

RESULTS

A total of 303 patients were recruited. Hepatic mass/malignancy followed by nonalcoholic liver disease were the most common diagnoses. Icterus followed by pruritus were the most common cutaneous complaints. The mean VAS and 5D itch scores among the patients with pruritus were 4.7 ± 1.9 and 13.6 ± 4.9. The most common mucocutaneous findings observed were icterus (241 patients; 79.5%), ichthyosis/xerosis (172 patients; 56.7%), pallor (131 patients; 43.2%), excoriations (118 patients; 38.9%), hyperpigmented palmar creases (118 patients; 38.9%), clubbing (113 patients; 37.2%), and pedal edema (85 patients; 28%). There was statistically significant correlation between serum bilirubin levels and pruritus.

CONCLUSION

The common mucocutaneous manifestations associated with primary hepatobiliary disorders were icterus, ichthyosis/xerosis, pallor, excoriations, hyperpigmented palmar creases, clubbing, and pedal edema.

Infectious Agents Associated with Head and Neck Carcinomas

In addition to traditional risk factors such as smoking habits and alcohol consumption, certain microbes also play an important role in the generation of head and neck carcinomas. Infection with high-risk human papillomavirus types is strongly associated with the development of oropharyngeal carcinoma, and Epstein-Barr virus appears to be indispensable for the development of non-keratinizing squamous cell carcinoma of the nasopharynx. Other viruses including torque teno virus and hepatitis C virus may act as co-carcinogens, increasing the risk of malignant transformation. A shift in the composition of the oral microbiome was associated with the development of oral squamous cell carcinoma, although the causal or casual role of oral bacteria remains to be clarified. Conversion of ethanol to acetaldehyde, a mutagenic compound, by members of the oral microflora as well as by fungi including Candida albicans and others is a potential mechanism that may increase oral cancer risk. In addition, distinct Candida spp. also produce NBMA (N-nitrosobenzylmethylamine), a potent carcinogen. Inflammatory processes elicited by microbes may also facilitate tumorigenesis in the head and neck region.

Thyroid Disease and Oral Lichen Planus as Comorbidity: A Prospective Case-Control Study

BACKGROUND

Thyroid disease has been mentioned to have a possible relation to the development of oral lichen planus (OLP).

OBJECTIVE

Because goiter is considered endemic in many countries, we proposed to determine whether thyroid disease constitutes a comorbidity of OLP.

METHODS

Two hundred and fifteen patients diagnosed as having OLP were evaluated concerning their serum thyroid-stimulating hormone and thyroxine (T4) levels. The results were contrasted with those obtained in control series of the same number of subjects matched for age and sex.

RESULTS

Diagnosis of thyroid disease was present in 15.3% of OLP patients (33/215) and in 5.2% (12/215) of the control group. In relation to OLP patients, the odds ratio of presence of thyroid disorders was 3.06 and that of using levothyroxine medication 3.21.

CONCLUSIONS

In the present study, OLP patients were associated with thyroid disease, specifically with hypothyroidism. Because most thyroid patients need T4 treatment, our findings confirmed that OLP and thyroid disease could be comorbidities.

Observational descriptive study of cutaneous manifestations in patients from Mato Grosso with viral chronic hepatitis

BACKGROUND

Extrahepatic manifestations are seen in association with chronic infection by hepatitis B or C virus including cutaneous disorders. The frequency of these findings seems to vary among different places and reports. There is a lack of information about this issue in Brazil.

OBJECTIVES

To estimate the prevalence of cutaneous findings affecting HBV or HCV carriers from a reference outpatient unit in Mato Grosso.

METHODS

A cross-sectional observational study.

RESULTS

108 patients were studied. 88.9% presented some cutaneous findings but must of them were nonrelated to chronic viral infection. Four patients had cutaneous or autoimmune syndromes that may be HBV or HCV related.

CONCLUSION

In our study we found no statistical association between viral hepatitis and skin diseases.

No association of oral lichen planus and hepatitis C virus infection in central Germany

OBJECTIVES

Co-occurrence of oral lichen planus (OLP) and chronic hepatitis C virus (HCV) infection suggests a strong association, but the relation between mucocutaneus, autoimmune lichen planus and HCV infection remains unclear. In areas with higher prevalence of HCV infection in general population, like Japan and southern Europe, 20 to 40 % of patients with OLP test positive for anti-HCV antibodies, whereas in German populations, a co-occurrence of 4.2 to 16 % was reported.

MATERIAL AND METHODS

We screened 143 patients with histopathologically proven OLP for prevalence of anti-HCV antibodies. Additionally, we examined 51 anti-HCV-positive subjects with current or past HCV infection for clinical symptoms of OLP. In all patients, confirmatory diagnosis was made by the detection of HCV RNA via reverse transcription-polymerase chain reaction (RT-PCR). A randomized control group comprised 109 blood sera samples of patients without any characteristics of OLP.

RESULTS

The results of all patients showed no co-occurrence in either cohort.

CONCLUSION

In conclusion, no association between oral lichen planus and chronic HCV infection in our study population was found.

CLINICAL RELEVANCE

Anti-HCV antibody screening in patients with confirmed oral lichen planus is not indicated routinely in central Germany.

Dermatologic Extrahepatic Manifestations of Hepatitis C

Hepatitis C virus (HCV) affects millions of people worldwide, and an estimated 3.2 million people in the United States. HCV is a hepatotropic and lymphotropic virus that causes not only liver disease, but also a significant number of extrahepatic manifestations (EHMs). Up to 74% of patients affected by HCV will have HCV-related EHMs of some severity in their lifetime. The EHMs vary from simple cutaneous palpable purpura to complex lymphoproliferative disorders, including lymphomas and immune-complex deposit diseases causing local and/or systemic complications. Mixed cryoglobulinemia (MC) is manifested by multiple systemic organ involvement, mainly skin, kidney, peripheral nerves, and salivary glands, and less frequently causes widespread vasculitis and malignant lymphoma. MC affects up to 3% of HCV-infected patients with cryoglobulinemia of clinical significance, i.e. >6%. Severe disease requires immunosuppressive or plasma exchange therapy. HCV prevalence in the United States in patients with porphyria cutanea tarda (PCT) was reported to be 66%, much higher than that in general population. Therefore, all patients with PCT should be screened for HCV. The skin rash of PCT varies from large blisters to small vesicles and/or milia on the hands. Skin manifestations due to PCT usually respond to anti-HCV treatment together with reducing skin sun exposure, avoiding triggers, having routine phlebotomy (especially for people with chronic iron overload states), and using chloroquine. Lichen planus (LP), which typically affects both the skin and oral mucosa is a chronic inflammatory disease of squamous cell origin affecting about 1% of the worldwide population. The prevalence of HCV in patients with LP varies based on geographic location. We review here the basic pathophysiology, clinical features, and management of dermatologic manifestations of HCV.

Subgrouping of patients with oral lichen planus according to cytochrome P450 enzyme phenotype and genotype

OBJECTIVE

This study aimed to determine if the activity of the environmentally influenced cytochrome P450 enzyme CYP1A2, alone or in combination with CYP2D6*4 genotype, discriminates subgroups of oral lichen planus (OLP) according to lifestyle factors and clinical manifestations.

STUDY DESIGN

A total of 111 patients with OLP were categorized according to normal, low, or high CYP1A2 activity and CYP2D6 4 genotype. Lifestyle parameters influencing the CYP1A2 activity and symptoms and manifestations of OLP were recorded.

RESULTS

Of the 111 patients, 21% had low, 65% normal, and 14% high CYP1A2 activity. The high-CYP1A2-activity group was more exposed to CYP1A2 inducers than the low-CYP1A2-activity group. In the normal-CYP1A2-activity group, more patients had a CYP2D6 4 genotype (58%) (P = .02), and they presented more symptoms (P = .003) and gingival lesions (P = .03). More patients in the low-CYP1A2-activity group and without CYP2D6 4 genotype presented red lesions (P = .04).

CONCLUSIONS

We suggest CYP2D6 4 genotype as a disease-susceptible genotype and low or high CYP1A2 activity levels as indicators of environmental influence in OLP subgroups.

Oral manifestations of hepatitis C virus infection

Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV.

A rare presentation of multiple primary squamous cell carcinoma of the tongue in a patient with recurrent hepatitis C infection

Hepatitis C virus (HCV) infection has been implicated as a risk factor for development of oral squamous cell carcinoma (SCC). Multiple primary sites of oral SCC associated with HCV infection occurs infrequently. This case report describes a rare presentation of multiple primary SCCs of the tongue in a patient with recurrent HCV cirrhosis status post liver transplant that required interdisciplinary medical and surgical management. It is important for oral health care providers to understand the local and systemic implications of HCV infection and perform routine clinical examinations to monitor for development of oral lesions and associated complications.

Novel therapies for oral lichen planus

Oral lichen planus (OLP) is a chronic mucocutaneous disorder commonly found in middle-aged women. Despite the progress in research and advance in knowledge on OLP, a successful management is still difficult to achieve. The main aim of OLP treatment is to control the symptoms of the affected patients. Steroids and other immunosuppressive drugs have been recommended and widely used in the treatment of OLP. Topical corticosteroids are the mainstay of OLP treatment, but strong evidence on their effectiveness is lacking. The effectiveness of alternative ways of managing OLP has been recently reported. Topical aloe vera, topical pimecrolimus and oral curcuminoids are the most promising of the new treatment modalities. Other interesting modalities are topically applied thalidomide and amlexanox. Nevertheless, the careful assessment between the risks and benefits of these drugs is crucial and larger and well-conducted trials need to confirm the above encouraging results.

Clinicopathological features and malignant transformation of oral lichen planus: a 12-years retrospective study

OBJECTIVE

Oral lichen planus (OLP) is known to be associated with the risk of developing oral squamous cell carcinoma (OSCC). The objective of this study was to investigate the clinicopathological features of OLP and the prevalence of malignant transformation in this setting.

MATERIALS AND METHODS

This retrospective study was carried out on 204 medical records of patients with histologically proven OLP who received long-term follow-up (range 6 months-12 years). Data were entered in an informatic database. The statistical analysis, when needed, was performed with the chi-squared test for significance (p < 0.05).

RESULTS

At the moment of the diagnosis, out of 204 patients (163 female and 41 male; mean age 54.5 years), 107 patients (52.45%) suffered from systemic chronic diseases, in particular 46 (22.5%) from hepatitis C. Clinically, the reticular form of OLP was the predominant one and most patients had multiple oral sites of involvement. Fourteen patients showed extra-oral lesions. A percentage of malignant transformation less than 1% was found. In fact, two patients (0.98%) underwent a malignant transformation at a site previously diagnosed as OLP.

CONCLUSIONS

At present, OLP is accepted as being a potential malignant disorder, therefore lifelong follow-up is recommended.

Oral conditions associated with hepatitis C virus infection

Hepatitis C virus (HCV) infection in more than 170 million chronically infected patients with no developed preventive vaccine is a globally important issue. In addition to expected hepatic manifestations, a number of extrahepatic manifestations, such as mixed cryoglobulinemia, glomerulonephritis, polyarteritis nodosa, rashes, renal disease, neuropathy, and lymphoma, have been reported following HCV infection, which are believed to be influenced by the virus or the host immune response. HCV combination therapy with pegylated interferon and ribavirin might be associated with side effects as well. The association of HCV with special oral conditions has also been reported recurrently; the mechanism of most of which remains unclear. This article reviews the association of HCV infection with some of the oral conditions such as oral health, Sjogren's syndrome, lichen planus and oral cancer.

Candidiasis and other oral mucosal lesions during and after interferon therapy for HCV-related chronic liver diseases

Background

Oral lichen planus (OLP) is seen frequently in patients with hepatitis C virus (HCV) infection. The aim of this study was to evaluate the occurrence of oral candidiasis, other mucosal lesions, and xerostomia during interferon (IFN) therapy for HCV infection.

Methods

Of 124 patients with HCV-infected liver diseases treated with IFN therapy in our hospital, 14 (mean age 56.00 ± 12.94 years) who attended to receive administration of IFN once a week were identified and examined for Candida infection and other oral lesions and for the measurement of salivary flow. Serological assays also were carried out.

Results

Cultures of Candida from the tongue surfaces were positive in 7 (50.0%) of the 14 patients with HCV infection at least once during IFN therapy. C. albicans was the most common species isolated. The incidence of Candida during treatment with IFN did not increase above that before treatment. Additional oral mucosal lesions were observed in 50.0% (7/14) of patients: OLP in three (21.4%), angular cheilitis in three (21.4%) and recurrent aphthous stomatitis in one (7.1%). OLP occurred in one patient before treatment with IFN, in one during treatment and in one at the end of treatment. 85.7% of the oral lesions were treated with topical steroids. We compared the characteristics of the 7 patients in whom Candida was detected at least once during IFN therapy (group 1) and the 7 patients in whom Candida was not detected during IFN therapy (group 2). The prevalence of oral mucosal lesions (P=0.0075) and incidence of external use of steroids (P=0.0308) in group 1 were significantly higher than in group 2. The average body weight of group 1 decreased significantly compared to group 2 (P=0.0088). Salivary flow decreased in all subjects throughout the course of IFN treatment and returned at 6^th months after the end of treatment. In group 1, the level of albumin at the beginning of the 6^th month of IFN administration was lower than in group 2 (P=0.0550). According to multivariate analysis, one factor, the presence of oral mucosal lesions, was associated with the detection of Candida. The adjusted odds ratio for the factor was 36.00 (95% confidence interval 2.68-1485.94).

Conclusion

We should pay more attention to oral candidiasis as well as other oral mucosal lesions, in patients with weight loss during IFN treatment.

Urban legends series: lichen planus

Oral Diseases (2012) Lichen planus (LP) is a common disorder affecting the oral cavity (OLP) and skin. Despite intensive research, LP/OLP etiology and treatment remain controversial. We investigated four controversial topics: (i) Is hepatitis C virus (HCV) infection associated with LP and involved in its pathogenesis? (ii) Should all patients with LP be screened for HCV? (iii) Should patients with OLP have all their amalgam restorations removed? (iv) Are there any new treatments for OLP? Results from extensive literature searches suggested that: (i) Robust evidence from three meta-analyses indicate that HCV is associated with LP and might be involved in OLP pathogenesis (ii) It would be prudent to screen patients with LP/OLP at significant risk with an ELISA for HCV antibodies using country-specific screening strategies (iii) There is no evidence that either OLP or oral lichenoid lesions patients would routinely benefit from having all their amalgam restorations replaced. Weak evidence from potentially very biased, small, non-randomized, unblinded studies suggests that a small fraction of patients may benefit from targeted amalgam replacement. (iv) There is weak evidence that, among new OLP treatments, topical pimecrolimus, aloe vera, and oral curcuminoids may be useful. The development of specific formulations for oral delivery of topical medications is a promising field.

Oral lichen planus as a preneoplastic inflammatory model

Oral lichen planus (OLP) is a chronic oral inflammatory disease of unknown etiology. According to reports, 1-2% of OLP patients develop oral squamous cell carcinoma (OSCC) in the long run. While World Health Organization (WHO) classifies OLP as “a potentially malignant disorder,” it is still a matter of debate which mechanisms drive OLP to such a condition. The current hypothesis connecting OLP and OSCC is that chronic inflammation results in crucial DNA damage which over time results in cancer development. Initial studies investigating the OLP and OSCC link were mainly retrospective clinical studies. Over the past years, several amount of information has accumulated, mainly from molecular studies on the OLP malignant potential. This article is a critical review of whether OLP has a malignant potential and, therefore, represents a model of preneoplastic inflammation.

A retrospective case-control study of hepatitis C virus infection and oral lichen planus in Japan: association study with mutations in the core and NS5A region of hepatitis C virus

Background

The aims of this study were to assess the prevalence of hepatitis C virus (HCV) infection in Japanese patients with oral lichen planus and identify the impact of amino acid (aa) substitutions in the HCV core region and IFN-sensitivity-determining region (ISDR) of nonstructural protein 5A (NS5A) associated with lichen planus.

Methods

In this retrospective study, 59 patients (group 1-A) with oral lichen planus among 226 consecutive patients who visited our hospital and 85 individuals (group 1-B, controls) with normal oral mucosa were investigated for the presence of liver disease and HCV infection. Risk factors for the presence of oral lichen planus were assessed by logistic regression analysis. We compared aa substitutions in the HCV core region (70 and/or 91) and ISDR of NS5A of 12 patients with oral lichen planus (group 2-A) and 7 patients who did not have oral lichen planus (group 2-B) among patients (high viral loads, genotype 1b) who received interferon (IFN) therapy in group1-A.

Results

The prevalence of anti-HCV and HCV RNA was 67.80% (40/59) and 59.32% (35/59), respectively, in group 1-A and 31.76% (27/85) and 16.47% (14/85), respectively, in group 1-B. The prevalence of anti-HCV (P < 0.0001) and HCV RNA (P < 0.0001) in group 1-A was significantly higher than those in group 1-B. According to multivariate analysis, three factors - positivity for HCV RNA, low albumin level (< 4.0 g/dL), and history of smoking - were associated with the development of oral lichen planus. The adjusted odds ratios for these three factors were 6.58, 3.53 and 2.58, respectively, and each was statistically significant. No significant differences in viral factors, such as aa substitutions in the core region and ISDR of NS5A, were detected between the two groups (groups 2-A and -B).

Conclusion

We observed a high prevalence of HCV infection in patients with oral lichen planus. Longstanding HCV infection, hypoalbuminemia, and smoking were significant risk factors for the presence of oral lichen planus in patients. It is advisable for Japanese patients with lichen planus to be tested for HCV infection during medical examination.

Differential expression of TLR-2 and TLR-4 in the epithelial cells in oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) is a chronic inflammatory condition of the mucosa mediated by a complex signalling network between the keratinocytes and the sub-epithelial lymphocytes. Since OLP occurs in constantly renewing epithelium continuously exposed to commensals, we hypothesised that the epithelial cell microflora interactions may mediate the persistent inflammation. By virtue of their ability to respond to most oral commensal microorganisms, the toll like receptor-2 (TLR-2) and TLR-4 are the most widely investigated receptors in oral diseases. The overall objective of this study was to investigate the role of TLR-2 and TLR-4 in OLP.

DESIGN

Systemically healthy OLP and control subjects were recruited after obtaining the institutional review board approval. Expression of TLR-2 and TLR-4 proteins and transcripts in the tissue epithelium and in the epithelial cells isolated from saliva were determined by immunohistochemistry and quantitative real-time polymerase chain reaction respectively.

RESULTS

The tissue epithelium and the salivary epithelial cells expressed reduced TLR-2 and increased TLR-4 proteins and transcripts in OLP. The salivary epithelial cells from OLP subjects secreted elevated IL-12. However, upon stimulation with bacterial lipopolysaccharide the epithelial cells from OLP exhibited a mixed Th1 (IL-12) and Th2 (IL-4) response. Presence of dexamethasone significantly reduced inflammatory cytokines in the in vitro stimulated cultures of salivary epithelial cells from OLP subjects.

CONCLUSION

Collectively, our data support a critical role for the host-microbial interactions in the OLP pathogenesis. The potential use of exfoliated oral epithelial cells in saliva for functional analysis exponentially increases its value as biological specimen for clinical research.

A study on the association with hepatitis B and hepatitis C in 1557 patients with lichen planus

BACKGROUND

Previous reports have demonstrated contradicting results on the association between lichen planus and hepatitis.

OBJECTIVES

The aim of this study was to investigate the association between lichen planus and viral hepatitis.

METHODS

Patients with lichen planus were compared with controls regarding the prevalence of viral hepatitis in a case-control study using logistic multivariate regression models. The study was performed utilizing the medical database of Clalit Health Services.

RESULTS

The study included 1557 lichen planus patients over the age of 20 years and 3115 age- and gender-matched controls. The prevalence of hepatitis C in patients with lichen planus was higher than that in the control group (1.9%, 0.4% respectively, P<0.001). In a multivariate analysis, lichen planus was associated with hepatitis C (OR 4.19, 95% CI 2.21; 7.93). The prevalence of hepatitis B in patients with lichen planus was similar to that in the control group (0.9%, 0.5% respectively, P=0.12). A multivariate analysis revealed that lichen planus was not associated with hepatitis B (OR 1.69, 95% CI 0.82; 3.47).

CONCLUSION

Lichen planus is associated with hepatitis C but not with hepatitis B. Physicians who care for patients with lichen planus should consider screening patients with lichen planus for hepatitis C.

The magnitude of the association between hepatitis C virus infection and oral lichen planus: meta-analysis and case control study

Although hepatitis C virus (HCV) infection is associated with oral lichen planus (OLP), a case-control study and a meta-analysis were designed to investigate the magnitude of such an association. A total of 413 presumptive OLP patients (18-75 years) who referred to a dental clinic in Rasht (Iran) were consecutively selected. OLP was diagnosed clinically (typical forms) and histologically (atypical forms) by a calibrated examiner. A total of 487 adults (20-77 years) attending the same dental clinic were the controls. The two groups were homogeneous in terms of age, gender and occupation. Subjects were tested for anti-HCV antibodies. The odds ratio (OR) for OLP attributable to HCV infection was non-significant [OR 1.2, 95% confidence interval (95CI) 0.3-4.8], suggesting that the association between HCV and OLP was weak in the Iranian context. Meta-analysis of observational studies characteristics of primary studies were that cases were diagnosed clinically (only typical forms) and histologically and exposure was assessed through anti-HCV antibodies. Exposed/unexposed cases/controls were extracted and zero values were appropriately transformed. As much as 44 studies, including the present, were located. Publication bias could not be totally excluded. The pooled OR, estimated using the random-effect model, was 2.8 (95CI 2.4-3.2). Sensitivity analysis confirmed the robustness of results. Subgroup analysis showed non-significant differences between American/European and Asian/African studies. The fraction of global OLP cases associated with HCV (population attributable fraction) was 2.1% (95CI 1.9-2.2%). Although HCV and OLP were significantly associated, the majority of OLP patients were not affected by HCV.

Non-alcoholic steatohepatitis (NASH) and oral lichen planus: a rare occurrence

Oral lichen planus (OLP) is frequently associated with hepatitis C virus infection but uncommonly with other causes of liver disorder. The authors report the case of a 41-year-old male patient with a clinical and histological diagnosis of OLP who presented with a marked alteration of the transaminase values, with no signs of past or present HBV, HCV, HGV or TTV infection. The patient did not consume alcohol and no exposure to hepatotoxic substances was reported. All autoantibodies were negative. Hepatic fine needle biopsy showed macrovesicular steatosis with a slight chronic portal inflammatory infiltrate and signs of siderosis. Iron metabolism was slightly altered. Genetic tests showed a heterozygotic mutation for hereditary haemochromatosis gene (HLA-H C282Y) but not for HLA-H63D. The patient presented slight insulin resistance but had normal glycaemic values. The results are consistent with a diagnosis of non-alcoholic steatohepatitis (NASH). This is the first reported case of NASH associated with OLP.

Hepatitis C virus and autoimmunity

Hepatitis C virus infection is associated with several extrahepatic manifestations. About 60% of patients infected with HCV develop at least one extrahepatic manifestation. The majority of these diseases seem to be triggered through autoimmune mechanisms, such as autoantibody production, autoreactive T cells and complex autoimmune mechanisms leading to systemic autoimmune disorders. In this review we categorize these diseases into three groups according to the main pathogenetic process involved, in particular B-cell-mediated, T-cell-mediated and complex autoimmune systemic diseases.

Microbiological findings in subjects with asymptomatic oral lichen planus: a cross-sectional comparative study

BACKGROUND

The bacterial colonization of the oral mucosa was evaluated in patients with asymptomatic oral lichen planus (OLP) and compared to the microbiologic status in mucosally healthy subjects.

METHODS

Bacteria from patients with clinically and histopathologically diagnosed OLP from the Stomatology Service, Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, were collected with a non-invasive swab system. Samples were taken from OLP lesions on the gingiva and from non-affected sites on the contralateral side of the mouth. The control population did not have OLP and was recruited from the student clinic. All samples were processed with the checkerboard DNA-DNA hybridization method using well-defined bacterial species for the analysis.

RESULTS

Significantly higher bacterial counts of Bacteroides ureolyticus (P = 0.001), Dialister species (sp.) (P = 0.006), Staphylococcus haemolyticus (P = 0.007), and Streptococcus agalactiae (P = 0.006) were found in samples taken from OLP lesions compared to sites with no clinical evidence of OLP. Significantly higher bacterial counts were found for Capnocytophaga sputigena, Eikenella corrodens, Lactobacillus crispatus, Mobiluncus curtisii, Neisseria mucosa, Prevotella bivia, Prevotella intermedia, and S. agalactiae at sites with lesions in subjects with OLP compared to sites in control subjects (P <0.001).

CONCLUSIONS

Microbiologic differences were found between sites with OLP and sites in subjects without a diagnosis of OLP. Specifically, higher counts of staphylococci and S. agalactiae were found in OLP lesions.

Prevalence of hepatitis C serum antibody in autoimmune diseases

OBJECTIVE

To evaluate the prevalence of serum antibodies against hepatitis C virus and other infectious agents in a large cohort of well-characterized patients with autoimmune diseases (AID).

METHODS

We utilized 1322 sera from patients with 18 different AID and 236 sera from healthy controls from the same countries and with similar age and sex distribution. All sera were tested for the presence of serum anti-hepatitis C virus (HCV) antibodies as well as antibodies directed at other infectious agents and autoantibodies.

RESULTS

Anti-HCV antibody was detected in 115/1322 (8.7%) of patients with AID and 0.4% of matched healthy controls (P < 0.0001). The prevalence of anti-HCV antibody was significantly higher in 7/18 different AID (i.e. cryoglobulinemia, mixed cryoglobulinemia pemphigus vulgaris, vasculitis, secondary anti-phospholipid syndrome, Hashimoto's thyroiditis, and inflammatory bowel disease) compared to controls. Patients with AID and serum anti-HCV positivity had an increased prevalence of antibodies against hepatitis B virus, Toxoplasma gondii and Cytomegalovirus as opposed to a lower frequency of serum autoantibodies.

CONCLUSIONS

The enhanced prevalence of anti-HCV serum antibodies in AID may suggest a role for HCV in tolerance to breakdown, similarly to its established role in mixed cryoglobulinemia. This immune mediated effect does not rule out the role of other infectious agents.