HCV infection and oral lichen planus: a weak association when HCV is endemic

Bidirectional Association between Lichen Planus and Hepatitis C-An Update Systematic Review and Meta-Analysis

Lichen planus (LP) is a chronic, inflammatory mucocutaneous disorder associated with systemic diseases such as hepatitis C (HCV). The objective of this study is to evaluate the association between LP and HCV bidirectionally through a systematic review and meta-analysis. A comprehensive search of studies published was performed in the databases of PubMed, Embase, and Web of Science. Out of 18,491 articles, 192 studies were included. The global prevalence of HCV positive (HCV+) in LP patients registered from 143 studies was 9.42% [95% confidence interval (CI), 7.27-11.58%], and from these, 84 studies showed HCV+ 4-fold more frequent in LP than a control group (OR, 4.48; 95% CI, 3.48-5.77). The global prevalence of LP in patients HCV+ recorded from 49 studies was 7.05% (95% CI, 4.85-9.26%), and from these, 15 registered a 3-fold more LP in HCV (OR, 3.65; 95% CI, 2.14-6.24). HCV+ in LP patients showed great geographic variability (OR, 2.7 to 8.57), and the predominantly cutaneous location was higher (OR, 5.95) than the oral location (OR, 3.49). LP in HCV+ patients was more frequent in the Eastern Mediterranean (OR, 5.51; 95% CI, 1.40-15.57). There is a higher prevalence of HCV+ in LP and vice versa than in the control group, especially in certain geographical areas that should be taken into consideration when doing screening in countries with an upper prevalence of HCV among the general population.

Oral Microbiome Research on Oral Lichen Planus: Current Findings and Perspectives

Simple Summary

Oral lichen planus is a disease of the oral mucosa, which frequently affects women aged 40 years or older. Though the T cell-mediated immune response is involved in the development of oral lichen planus, attempts to identify a microorganism that causes the disease have been unsuccessful. Recent studies on the development of oral lichen planus are focusing on the role of the oral microbiome, which includes oral microbiota and their products, and the host environment. The role of the human microbiome in various diseases has been identified and regulating the microbiome is becoming important in personalized medicine. In this review, we summarized current findings on the role of the oral microbiome in the development of oral lichen planus. The homeostasis of the oral microbiome is disrupted in patients, and functional analysis of oral microbiota and oral mucosa implies that pathways involved in defense against bacterial infection and in the inflammatory response are activated in the oral lichen planus-associated oral microbiome. Though the lack of studies to date makes it difficult to conclude, further studies on the oral microbiome associated with the disease will enable a holistic understanding of the role of the oral microbiome in the development of oral lichen planus and developing a personalized therapy for the disease.

Abstract

Oral lichen planus (OLP) is a chronic inflammatory disease of the oral mucosa with an unknown etiology. The role of oral microbes in the development of OLP has gained researchers’ interest. In this review, we summarized the findings of studies focused on the relationship between OLP and oral microbiome, which includes the composition of oral microbiota, molecules produced by oral microbiota or the host, and the oral environment of the host. According to the studies, the oral microbial community in OLP patients undergoes dysbiosis, and the microbial dysbiosis in OLP patients is more prominent in the buccal mucosa than in the saliva. However, no same microorganisms have been suggested to be associated with OLP in multiple investigations, implying that the functional aspects of the oral microbiota are more important in OLP development than the composition of the oral microbiota. According to studies on host factors that make up the oral environment, signal pathways involved in cellular processes, such as keratinization, inflammation, and T cell responses are triggered in OLP. Studies on the functional aspects of the oral microbiota, as well as interactions between the host and the oral microbiota, are still lacking, and more research is required.

The microbiology of oral lichen planus: Is microbial infection the cause of oral lichen planus?

Oral lichen planus (OLP) is a variant of lichen planus (LP), a common chronic mucocutaneous inflammatory disease. Cutaneous lesions of LP are self-limiting, but OLP lesions are non-remissive, alternating periods of exacerbation and quiescence, and only symptomatic treatments exist for OLP. The precise etiology and pathogenesis of OLP are hardly understood, which is a major obstacle to the development of new therapeutics for this disease. OLP is considered a T-cell-mediated inflammatory disease. Although various antigens have been considered, what actually triggers the inflammatory response of T cells is unknown. Suggested predisposing factors include genetic factors, stress, trauma, and infection. The aim of this review was to determine whether microbial infection can cause OLP. We first reviewed the association between OLP and microbial factors, including viral, fungal, and bacterial infections. In addition, each microbial factor associated with OLP was assessed by modified guidelines of Fredricks and Relman to determine whether it establishes a causal relationship. In conclusion, no microbial factor yet fulfills the guidelines to establish the causality of OLP. By focusing on the unclarified issues, however, the potential roles of microbial factors in the pathogenesis of OLP will be soon elucidated.

Lack of evidence of hepatitis in patients with oral lichen planus in China: A case control study

Background

China has been one of the countries with high prevalence of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) liver disease. And lichen planus is an extrahepatic manifestation of patients with chronic HCV infection. This case-control study was conducted to investigate the relationship between oral lichen planus (OLP) and HBV/HCV infection in China.

Material and Methods

A total of 776 patients, including 150 patients with OLP (Group OLP), 429 inpatients from the Trauma Ward of Oral and Maxillofacial Surgery Department (Group A), 110 patients with other oral mucosal diseases, but without a reported association with HCV infection (Group B) and 87 patients with oral lichenoid lesion (Group OLL), were compared with their seroprevalence of anti-HCV antibody (HCVAb), hepatitis B surface antigen (HBsAg) and the parameters of liver functions. Moreover, the clinical characteristics of OLP were also observed, such as gender, age, chief complaint, course of the disease, clinical type, sites involved and so on.

Results

The positive rates of HCVAb and HBsAg in OLP patients were 0.7% and 4%, respectively. Neither HCVAb nor HBsAg was associated with OLP as demonstrated by both the univariate and the multivariate analyses. The clinical features and liver functions of OLP patients with negative or positive HBsAg were nearly the same.

Conclusions

Our findings verify that there is no association between OLP and hepatitis and there is no need to run a screening test for HCV or HBV in OLP patients in China.

Key words:Oral lichen planus, hepatitis C virus, hepatitis B virus.

Role of distinct CD4(+) T helper subset in pathogenesis of oral lichen planus

Oral lichen planus (OLP) is one of the most common chronic inflammatory oral mucosal diseases with T-cell-mediated immune pathogenesis. In subepithelial and lamina propria of OLP local lesions, the presence of CD4(+) T helper (CD4(+) Th) cells appeared as the major lymphocytes. These CD4(+) T lymphocytes can differentiate into distinct Th cell types such as Th1, Th2, Treg, Th17, Th22, Th9, and Tfh within the context of certain cytokines environment. Growing evidence indicated that Th1/Th2 imbalance may greatly participate into the cytokine network of OLP immunopathology. In addition, Th1/Th2 imbalance can be regulated by the Treg subset and also greatly influenced by the emerging novel CD4(+) Th subset Th17. Furthermore, the presence of novel subsets Th22, Th9 and Tfh in OLP patients is yet to be clarified. All these Th subsets and their specific cytokines may play a critical role in determining the character, extent and duration of immune responses in OLP pathogenesis. Therefore, we review the roles of distinct CD4(+) Th subsets and their signature cytokines in determining disease severity and susceptibility of OLP and also reveal the novel therapeutic strategies based on T lymphocytes subsets in OLP treatment.

Possible association between hepatitis C virus and malignancies different from hepatocellular carcinoma: A systematic review

AIM: To summarize the current knowledge about the potential relationship between hepatitis C virus (HCV) infection and the risk of several extra-liver cancers.

METHODS: We performed a systematic review of the literature, according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) Statement. We extracted the pertinent articles, published in MEDLINE and the Cochrane Library, using the following search terms: neoplasm/cancer/malignancy/tumor/carcinoma/adeno-carcinoma and non-Hodgkin lymphomas, kidney/renal-, cholangio-, pancreatic-, thyroid-, breast-,oral-, skin-, prostate-, lung-, colon-, stomach-, haematologic. Case series, case-series with control-group, case-control, cohort-studies as well as meta-analyses, written in English were collected. Some of the main characteristics of retrieved trials, which were designed to investigate the prevalence of HCV infection in each type of the above-mentioned human malignancies were summarised. A main table was defined and included a short description in the text for each of these tumours, whether at least five studies about a specific neoplasm, meeting inclusion criteria, were available in literature. According to these criteria, we created the following sections and the corresponding tables and we indicated the number of included or excluded articles, as well as of meta-analyses and reviews: (1) HCV and haematopoietic malignancies; (2) HCV and cholangiocarcinoma; (3) HCV and pancreatic cancer; (4) HCV and breast cancer; (5) HCV and kidney cancer; (6) HCV and skin or oral cancer; and (7) HCV and thyroid cancer.

RESULTS: According to available data, a clear correlation between regions of HCV prevalence and risk of extra-liver cancers has emerged only for a very small group of types and histological subtypes of malignancies. In particular, HCV infection has been associated with: (1) a higher incidence of some B-cell Non-Hodgkin-Lymphoma types, in countries, where an elevated prevalence of this pathogen is detectable, accounting to a percentage of about 10%; (2) an increased risk of intra-hepatic cholangiocarcinoma; and (3) a correlation between HCV prevalence and pancreatic cancer (PAC) incidence.

CONCLUSION: To date no definitive conclusions may be obtained from the analysis of relationship between HCV and extra-hepatic cancers. Further studies, recruiting an adequate number of patients are required to confirm or deny this association.

The association between oral lichen planus and hepatitis C virus infection; a report from northeast of iran

Background:

The association between hepatitis C virus (HCV) infection and oral lichen planus (OLP) has been the focus of many studies. Fifteen percent of HCV infections lead to sets of extrahepatic manifestations including lichen planus (LP). The prevalence of HCV is heavily influenced by geographical location.

Objectives:

This study aimed to evaluate the relationship between OLP and HCV infection in Mashhad, northeast of Iran.

Materials and Methods:

Blood samples were taken from 134 OLP patients and 134 healthy controls (without OLP) to screen for anti-HCV by ELISA (third generation) and reverse transcription polymerase chain reaction (RT-PCR) for HCV-RNA.

Results:

Of the 134 OLP patients only three (2.23 %) had HCV infection where both anti-HCV and HCV-RNA were positive. All controls were negative for both anti-HCV and HCV-RNA (P = 0.082).

Conclusions:

Our investigation illustrated that the prevalence of hepatitis C was higher among OLP patients compared to the control group. These findings are in line with previous results that reported a hepatitis C prevalence of 0.19% among the general population of Mashhad.

Oral lichen planus: focus on etiopathogenesis

Lichen planus is a chronic mucocutaneous inflammatory disease, which frequently affects the oral mucosa of white females over 40 years old. Its aetiology remains uncertain and the pathogenesis is still the object of much speculation. The present paper presents the most well known antigens, and describes the action of different cells and proteins associated with the development of that disease, as well as the possible agents involved with its malignant transformation. Different external agents, especially virus, and internal agents, like stress, and the heat shock protein antigen expression, associated or not, can alter the basal keratinocytes of the oral mucosa making them susceptible to apoptosis by CD8(+) cytotoxic T cell as well as activate matrix metalloproteinase and mast cell degranulation, which produce a great range of inflammatory mediators and cytokines determining the clinical onset of the disease. Regarding carcinogenesis, since it is a complex process and presents multifactorial origin, it is believed that there may be a synergism between intrinsic, such as inflammation mediators, and extrinsic agents (tobacco, alcohol, viral infections) for the OLP malignant transformation to occur. However, further studies are needed to better understand the origin, pathogenesis and process of malignant transformation of OLP.

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.

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.

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

Some of the most frequent extrahepatic manifestations of hepatitis C virus (HCV) infection involve the oral region predominantly or exclusively. Part 2 of this review discusses the current evidences regarding the association of lichen planus (LP) and other diseases frequently involving the oral cavity with HCV. Epidemiological data suggest that LP may be significantly associated with HCV infections especially in southern Europe and Japan but not in northern Europe. These geographical differences are possibly influenced by immunogenetic factors, the duration of the HCV infection and the design of the published studies. Because of the fact that most of the studies published are retrospective, it is impossible to establish whether the HCV exposure occurred earlier to or after the onset of disease and more prospective studies are clearly warranted. As the virus may replicate in the skin and oral mucosa and HCV-specific T lymphocytes can be found in the oral mucosa of patients with chronic hepatitis C and LP, HCV may be implicated in the pathogenesis of LP. However, little attention has been paid to the variable effect of therapy with interferon-alpha (IFN-alpha), with or without ribavirin for LP. Conversely, it is unlikely that other oral diseases such as oral carcinoma, pemphigus and Behcet disease are triggered by HCV.

Hepatitis C virus chronic infection and oral lichen planus: an Italian case-control study

OBJECTIVE

The aim of the study was to investigate the possible epidemiological relationship between hepatitis C virus (HCV) chronic infection and oral lichen planus (OLP) in centre-south Italy.

METHODS

In a case-control study three groups of patients were investigated: group 1 (82 patients): patients with histologically confirmed OLP were tested for HCV infection; group 2 (165 patients): patients with chronic HCV infection were examined for OLP; group 3 (466 participants): control group: healthy individuals who had been hospitalized in the Trauma-Orthopaedic Ward and had been tested for HCV.

RESULTS

In group 1, 11.4% of the participants were HCV-positive and HCV was found in 10.8% of the patients above 50 years of age. Eight participants (5.5%) of group 2 showed lesions possibly related to OLP: only two had a histology consistent with OLP. In group 3, 5.4% participants had chronic HCV infection, but HCV was found in 10% of the participants of 50 years and above. A weak overall association between HCV and OLP (odds ratio 2.27; 95% confidence interval 0.94, 5.35; P<0.05) was seen and the result was not statistically significant in participants aged 50 years and above (odds ratio 1.08; 95% confidence interval 0.39, 2.88; P=0.86).

CONCLUSION

Our data suggest that no clear association exists between OLP and chronic HCV disease. It is possible that the association is mainly due to the frequency of each disease in the population.

Extrahepatic manifestations in patients with chronic hepatitis C virus infection

PURPOSE OF REVIEW

Chronic hepatitis C virus infection often has autoimmune clinical and analytic features. This review analyzes recent data on the close association of chronic hepatitis C virus infection with autoimmune and lymphoproliferative processes.

RECENT FINDINGS

Hepatitis C virus infection has been associated with both organ-specific (thyroiditis, diabetes) and systemic autoimmune diseases. Experimental, virologic, and clinical evidence has demonstrated a close association between hepatitis C virus infection and Sjögren syndrome, with hepatitis C virus-associated Sjögren syndrome being indistinguishable in most cases from the primary form. With respect to rheumatoid arthritis, patients with hepatitis C virus-related polyarthritis and positive rheumatoid factor may fulfill the classification criteria for rheumatoid arthritis. Hepatitis C virus has also been associated with an atypical presentation of antiphospholipid syndrome, as well as with the development of sarcoidosis. A higher prevalence of hematologic processes in patients with hepatitis C virus infection has recently been reported, including cytopenias and lymphoproliferative disorders. Recent data are available on the use of new immunosuppressive and biologic agents (mainly mycophenolate mofetil, anti-tumor necrosis factor agents, and rituximab) in patients with hepatitis C virus infection and autoimmune or lymphoproliferative manifestations.

SUMMARY

There is increasing evidence of a close association of hepatitis C virus infection with autoimmune and hematologic processes. The sialotropism of hepatitis C virus may explain the close association with Sjögren syndrome, and its lymphotropism links the virus to cryoglobulinemia, autoimmune cytopenias, and lymphoma. The substantial overlap between cryoglobulinemic features and the classification criteria for some systemic autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, and polyarteritis nodosa) make the differentiation between mimicking and coexistence difficult.

Oral lichen planus, hepatitis C virus, and HIV: No association in a cohort study from an area of high hepatitis C virus endemicity

OBJECTIVES

We sought to assess the age-specific prevalence of oral lichen planus (OLP) in Mediterranean patients with chronic hepatitis C virus (HCV) and to evaluate the features of OLP in relation to sex, smoking, HCV genotype, HIV-1 coinfection, and antiviral treatments.

METHODS

In all, 178 anti-HCV-positive adults (60 women and 118 men; age range 20-66 years) recruited from two cohorts (104 HIV-negative patients and 74 patients with HIV coinfection) underwent oral examination.

RESULTS

Overall prevalence of OLP was 2.8% (5 of 178) (male/female ratio 0.2; odds ratio=0.119; 95% confidence interval=0.013-1.106), only among HIV-negative participants, always in the reticular pattern, and in the adult age. HCV genotype, tobacco smoking, and treatment (interferon alfa/ribavirin) were not significantly associated to OLP.

CONCLUSIONS

Among HCV-infected patients, we found a low prevalence of OLP. The absence of OLP in HIV-coinfected patients suggests immunosuppression secondary to defective CD4 functions.