Attenuation of Hydrogen Peroxide and Ferric Reducing/Antioxidant Power Serum Levels in Colorectal Cancer Patients with Intestinal Parasitic Infection

Background: This study assessed several common oxidative indices in subjects infected with intestinal parasites, as well as in colorectal cancer (CRC) patients both with and without intestinal parasites.

Method: Serum levels of malondialdehyde (MDA), ferric reducing/antioxidant power (FRAP), and hydrogen peroxide (H₂O₂) were measured, as were plasma levels of advanced oxidation protein products (AOPP), all according to established methods. The presence of intestinal parasites was confirmed by stool examination.

Results: All intestinal parasiteinfected subjects and CRC patients showed the presence of oxidative stress. Thirtysix percent of the CRC patients had intestinal parasitic infections. The levels of H₂O₂ and FRAP in parasite-infected subjects were significantly higher than in CRC patients, but these levels were significantly lower in the CRC patients with parasitic infections.

Conclusion: Parasitic infection and CRC may contribute to oxidative stress independently, but when present together, the oxidative stress burden imposed by parasites may be attenuated.