Vitamin A and lipid peroxidation in patients with different forms of leprosy.

Leprosy, a chronic infectious disease, is caused by a Mycobacterium leprae infection. After India, Brazil has the second greatest number of cases in the world. Increase of oxidative stress and antioxidant deficiency are present in infected subjects and can be related to infection progression. We studied alterations in serum levels of lipid peroxidation (LPO) and vitamin A in patients with different forms of leprosy. Four groups of leprosy patients and a control group (healthy subjects) were selected, and their vitamin A serum levels and LPO profile, measured as malonaldehyde (MDA) were measured by spectrophotometric assays. The mean MDA serum levels (micromol/L) were 3.80 +/- 0.5 for control group and 10.54 +/- 1.1 in the leprosy patients and this increase was gradual, being more accentuated in severe forms of the disease. Also, the vitamin A serum levels (microg/dL) were diminished in the infected subjects (38.51 +/- 4.2), mainly in lepromatous form, when compared with the control group (53.8 +/- 5.6). These results indicate that LPO can be an important factor in Mycobacterium leprae infection, which can be related to increases in phagocytic activity and the general breakdown of antioxidants, contributing to an increase of LPO during infection progression. The evaluation of oxidant/antioxidant status in these patients can be an important factor in the treatment, control, and/or prognosis of this disease.