Oxidative stress determined through the levels of antioxidant enzymes and the effect of N-acetylcysteine in aluminum phosphide poisoning

INTRODUCTION: The primary objective of this study was to determine the serum level of antioxidant enzymes and to correlate them with outcome in patients of aluminum phosphide (ALP) poisoning and, secondly, to evaluate the effect of N-acetylcysteine (NAC) given along with supportive treatment of ALP poisoning. DESIGN: We conducted a cohort study in patients of ALP poisoning hospitalized at a tertiary care center of North India. The treatment group and control group were enrolled during the study period of 1 year from May 2011 to April 2012. INTERVENTIONS: Oxidative stress was evaluated in each subject by estimating the serum levels of the enzymes, viz. catalase, superoxide dismutase (SOD) and glutathione reductase (GR). The treatment group comprised of patients who were given NAC in addition to supportive treatment (magnesium sulfate and vasopressors, if required), while in the control group, only supportive treatment was instituted. The primary endpoint of the study was the survival of the patients. MEASUREMENTS AND RESULTS: The baseline catalase (P = 0.008) and SOD (P < 0.01) levels were higher among survivors than non-survivors. Of the total patients in the study, 31 (67.4%) expired and 15 (32.6%) survived. Among those who expired, the mean duration of survival was 2.92 ± 0.40 days in the test group and 1.82 ± 0.33 days in the control group (P = 0.043). CONCLUSIONS: This study suggests that the baseline level of catalase and SOD have reduced in ALP poisoning, but baseline GR level has not suppressed but is rather increasing with due time, and more so in the treatment group. NAC along with supportive treatment may have improved survival in ALP poisoning.