Characterization of anti-nuclear antibodies in patients with oral submucous fibrosis and its clinicopathologic implications – An immunofluorescence study

BACKGROUND: Oral submucous fibrosis (OSF), widespread in the Indian subcontinent, is a chronic debilitating disease of the oral cavity having a high potential for malignancy. The etiology of OSF is debatable. However, recently, autoimmunity had been suggested to play a significant role in its etiology, yet unproven. Hence, this study was conducted to explore the presence of antinuclear antibodies (ANAs) in the serum of OSF patients which is one of the serum markers of autoimmune diseases and its possible clinicopathologic associations. MATERIALS AND METHODS: A total of 105 blood samples were collected from patients with OSF (n = 45), age- and sex-matched healthy controls with (n = 30) and without (n = 30) areca nut chewing habit. Serum positivity of ANA was determined by immunofluorescence and correlated with the oral habits and severity of the disease measured by maximum mouth opening (MMO) and site of involvement. RESULTS: Significantly higher incidence of ANA (35.6%) was found in 45 OSF patients than in the healthy group (P = 0.001). Prevalence of ANA positivity was found higher in females (n = 11; 68%) than males (P < 0.001). A significantly lower MMO (P = 0.00) was found in ANA positive patients (17 ± 6.21 mm) in contrast to MMO in ANA-negative patients (28.74 ± 6.58 mm). The mean duration of habit and frequency of habit between ANA positive and negative patients was not significant. A significantly more number of sites of involvement was seen in ANA positive cases (P = 0.004). Out of 16 ANA positive OSF cases, 10 cases showed + 2 and 6 cases showed + 3 fluorescence intensity. Speckled (n = 8), homogeneous (n = 5) and nucleolar pattern (n = 3) were the fluorescence patterns observed. CONCLUSION: The presence of autoantibodies such as ANA, female predilection, alteration of humoral and cellular immunity justifies OSF as an autoimmune disease. This study provides broader prospective to adopt therapies that selectively target autoimmune pathways.