Association between hepatitis C infection in Thai patients with oral lichen planus: A case-control study

Role of Oral Microbiota Dysbiosis in the Development and Progression of Oral Lichen Planus

Oral lichen planus (OLP) is a chronic inflammatory autoimmune disease of the oral cavity with malignant potential affecting 1.01% of the worldwide population. The clinical patterns of this oral disorder, characterized by relapses and remissions of the lesions, appear on buccal, lingual, gingival, and labial mucosa causing a significant reduction in the quality of life. Currently, there are no specific treatments for this disease, and the available therapies with topical and systemic corticosteroids only reduce symptoms. Although the etiopathogenesis of this pathological condition has not been completely understood yet, several exogenous and endogenous risk factors have been proposed over the years. The present review article summarized the underlying mechanisms of action involved in the onset of OLP and the most well-known triggering factors. According to the current data, oral microbiota dysbiosis could represent a potential diagnostic biomarker for OLP. However, further studies should be undertaken to validate their use in clinical practice, as well as to provide a better understanding of mechanisms of action and develop novel effective intervention strategies against OLP.

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.

Are oral lichen planus patients at high risk of hepatitis C? A case-control study

OBJECTIVE

To assess the correlation between oral lichen planus (OLP) and viral hepatitis C (HCV).

METHODS

This retrospective case-control study included a sample of OLP patients in a 3-year interval. The predictor variable was the presence of OLP (yes/no). The outcome variable was the diagnosis of HCV. Other study variables were grouped into demographic, anatomic, and clinical. Descriptive, bi- and multivariate statistics were computed with a significant level at P ≤ 0.05.

RESULTS

The sample was composed of 237 OLP patients (38.8% females) with a mean age of 59.9 ± 17.8 years (range, 17-96), and 948 age- and gender-matched control individuals. The significant higher frequency of HCV was identified in OLP patients (frequency: 19.8% vs. 2.1%; adjusted matched odds ratio [mOR_adj], 9.5; 95% confidence interval [95% CI], 5.98 to 15.91; P < 0.0001; Pearson's Phi coefficient [r_phi], 0.307). In the adjusted model, OLP with HCV was associated with 1) oro-cutaneous manifestations (mOR_adj, 17.58; 95% CI, 1.92 to 161.26; P = 0.0059; Bayesian posterior probability of positive test [W_p], 96%), 2) any intraoral forms other than reticular/plaque-liked forms (mOR_adj, 0.09; 95% CI, 0.04 to 0.18; P < 0.0001; W_p, 52%), and 3) poor response to topical corticosteroids (mOR_adj, 0.05; 95% CI, 0.02 to 0.16; P < 0.0001; W_p, 88%).

CONCLUSIONS

OLP, especially oro-cutaneous disease or steroid-refractory OLP, are associated with an increased frequency of HCV. Not only HCV screening in OLP patients, but oral examination in HCV patients, are both recommended as primary preventive measures.

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.