Lesional levels of superoxide dismutase and malondialdehyde in paucibacillary and multibacillary leprosy patients

Background: Leprosy or Hansen’s disease (HD) is a chronic infectious disease caused by Mycobacterium leprae. The ratio of malondialdehyde (MDA)/superoxide dismutase (SOD) may be considered as an index of oxidative stress (OS).

Objective: To assess the OS by estimating the levels of antioxidant enzyme (SOD), lipid peroxidation products (MDA) and the ratio of MDA/SOD in the skin of paucibacillary (PB) and multibacillary (MB) leprosy patients.

Patients and methods: This case-control study was conducted on 41 untreated leprosy patients (18 patients with PB type and 23 patients with MB type) attending Sohag’s Dermatology and Leprosy Clinic, in addition to 18 healthy controls. Colorimetric assays of MDA and SOD levels in the tissue homogenates of the skin biopsies taken from the patient and control groups were performed.

Results: There were statistically significantly higher levels of tissue MDA and statistically significantly lower levels of tissue SOD in leprosy patients when compared with the control group (P<0.001) and in MB leprosy patients when compared with PB leprosy patients (P<0.001). There was statistically significantly higher tissue OS in leprosy patients when compared with the control group (P<0.01) and in MB leprosy patients when compared with PB leprosy patients (P<0.001). There were significant negative correlations between SOD with both MDA and OS with a significant positive correlation between MDA and OS in both patients versus controls and in MB leprosy versus PB leprosy patients (P<0.01 for all).

Conclusion: OS may play an important role in the pathogenesis of leprosy. The imbalance between oxidant/antioxidant mechanisms may be the contributing factor in the severity of the disease.