New Oxidative Stress Markers Useful in the Diagnosis of Acute Appendicitis in Children: Thiol/Disulfide Homeostasis and the Asymmetric Dimethylarginine Level.

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate 2 new oxidative stress markers, thiol/disulfide homeostasis status and the asymmetric dimethylarginine (ADMA) level, in children with acute appendicitis (AA) and to evaluate their diagnostic utility. METHODS: This case-control study included 45 patients with AA and 35 healthy children. Age, sex, white blood cell count, neutrophil-to-lymphocyte ratio, high-sensitivity C-reactive protein (hs-CRP) level, ultrasonographic findings, thiol/disulfide homeostasis parameters (native and total thiol levels, native thiol/total thiol ratios [antioxidant parameters], and disulfide, disulfide/native thiol, and disulfide/total thiol ratios [oxidant parameters]), and the ADMA level were compared between the 2 groups. RESULTS: The native and total thiol levels, and the native thiol/total thiol ratio, were significantly lower, and the disulfide level and disulfide/native thiol and disulfide/total thiol ratios significantly higher, in the AA compared with the control group (all P < 0.001). The ADMA level was significantly higher in a perforated versus nonperforated subgroup of AA patients, but the thiol/disulfide homeostasis parameters did not differ significantly between the two subgroups. In addition, the hs-CRP level and appendiceal wall thickness were higher in the perforated subgroup. The thiol/disulfide antioxidant parameters and ADMA level correlated negatively with the white blood cell count, the neutrophil-to-lymphocyte ratio, and the hs-CRP level, in the AA group, but correlated positively with oxidant parameters. The sensitivity and specificity of the disulfide/native thiol and disulfide/total thiol ratios were high when used to diagnose AA, whereas the sensitivity of the ADMA level was high when used to diagnose perforated appendicitis. CONCLUSIONS: Thiol/disulfide homeostasis and the ADMA level, together with certain other parameters, may be useful biomarkers of AA in children.