TMSS Medical College Journal

Background: Lichen planus (LP) is an autoimmune inflammatory disease of the mucocutaneous tissue, whose exact pathogenesis is not yet understood. Uric Acid (UA) is one of the important antioxidants in plasma which can scavenge reactive oxygen species (ROS). This study aimed to compare the serum uric acid (UA) levels in lichen planus patients with other dermatoses. Materials and Methods: This cross sectional comparative study was conducted among purposively selected 70 patients at the Department of Dermatology and Venereology of Bangabandhu Sheikh Mujib Medical University, Dhaka from December 2016 to January 2018 where 35 patients with LP and the rest of 35 patients with other skin disease were enrolled as case and control respectively in the study. All the patients diagnosed clinically and histopathologically were included in the study after fulfilling the criteria. The statistical analysis was done by using the Statistical Package for Social Sciences (SPSS) Windows version 22. Descriptive and inferential analysis was carried out for categorical and numerical data. Results: The mean age of patients with lichen planus and other dermatoses was 37.80+14.92 years and 33.60+9.61 years, respectively. The most common types of LP were classical 18(51.4%).The mean serum UA levels in patients with lichen planus and other dermatoses were 4.09+1.07 and 5.63+1.28 mg/dl, respectively and the difference between the mean of the two groups was 1.537 mg/dl (p<0.005). There was a significant negative correlation with duration of disease (months) and uric acid where Correlation-Coefficient or ‘r’-value was +0.448 (p=0.007). Conclusion: Serum uric acid level is lower in lichen planus patients compare to that of other dermatoses. Serum uric acid level is negatively correlated with duration of the disease in lichen planus patients.

Lichen planus (LP) is a sub-acute to chronic, inflammatory, papulosquamous disorder characterized by typical lesions.! LP is a very common disorder with 0.2-1% prevalence worldwide. Outpatients in the dermatology domain account for about 0.38% of cases of LP. Regardless of gender and caste, it is commonly seen in the population aged 30-70 years.? The cause of LP is still under the microscope, but it is assumed that it is mainly due to an overreaction of the skin's immune/defense system. Although the exact pathogenesis is unknown, works of the literature suggest that cell-mediated immunity and humoral immunity are involved in the development of LP. Activation of the cell-mediated immune response constitutes three processes such as LP-specific antigen recognition, cytotoxic lymphocyte activation, and keratinocyte apoptosis which are considered as the prime event in the pathogenesis of LP.** Recently, it has been suggested that free radicals play an important role in the underlying mechanism of various skin diseases, including LP. In addition, oxidative stress which refers to a condition where an increased reactive oxygen species (ROS) production overwhelms the antioxidant defense mechanisms can promote local tissue damage.” Oxidative stress is involved in the pathogenesis of many skin diseases such as melanoma and non-melanoma skin cancers ® psoriasis vitiligo * and chronic urticarial’ and Behcet's disease '* Along with these, study report that oxidative stress may have a role to play in the pathogenesis of lichen planus. Uric acid (UA) is a powerful free radical scavenger and is thought to contribute >50% of the antioxidant capacity of blood '*'* which means it acts as a defense against oxidative stress like other antioxidants such as enzymes, vitamins etc. Many studies have revealed the antioxidant role of UA in other dermatological conditions like LP. #15 1¢