Factors associated with non-response to etiological therapy in patients with Opisthorchis felineus invasion

Background. The contribution of opisthorchiasis to damage to the liver and biliary system is very significant, especially in Southeast Asia and Russia. The carcinogenicity of this disease is a serious problem. At the same time, insufficient attention is paid to the optimization of treatment methods for opisthorchiasis, and the factors associated with non-response to etiological therapy remain practically unexplored. Objective. Evaluation of the factors associated with non-response to etiological therapy in patients with Opisthorchis felineus invasion. Methods. The study included 58 patients (32 men, 26 women, mean age - 47.2 years) with a diagnosed Opisthorchis felineus invasion, who received etiological therapy for opisthorchiasis with the monitoring of effectiveness of treatment 4-6 months after the end of anthelmintic therapy. All patients underwent clinical examination, full blood exam and biochemical blood test, esophagogastroduode-noscopy, ultrasound examination of the abdominal organs, liver elastometry with an assessment of fibrosis according to the METAVIR scale, determination of markers of oxidative stress (malondialdehyde) and antioxidant defense (catalase and superoxide dismutase) in the blood. Antiparasitic therapy included three stages: 1st - preparatory (baseline pathogenetic therapy) with the use of choleretics, antispasmodics and hepatoprotectors, 2nd - specific therapy with praziquantel, and 3rd stage - rehabilitation (restorative), similar in composition to drugs with 1st stage. Results. Of the 58 examined patients, the eradication of opisthorchiasis was achieved in 47 individuals, 11 did not respond to treatment. The incidence of hepatomegaly, irritable bowel syndrome and articular syndrome in «non-responders» significantly exceeded the same indicator in those who responded to treatment. The incidence of F3-F4 liver fibrosis according to METAVIR in “nonresponders"prevailed in comparison with those in patients who responded to treatment (45.5% versus 8.5%; p=0.01). The blood malondialdehyde level was 95 ng/ml in nonresponders to etiological treatment and 68 ng/ml in patients with opisthorchiasis with achieved eradication of O. felineus (p=0.01). Conclusion. We have demonstrated for the first time that patients who do not respond to the standard etiological treatment of opisthorchiasis are objectively different from those with a positive response to treatment. The markers, allowing to predict a high probability of an unfavorable result of therapy, include the presence of hepatomegaly, severe liver fibrosis and an increased blood malondialdehyde level, indicating a high probability of intense inflammation in hepatocytes. It is obvious that special approaches to therapy should be developed for patients with the presence of the above factors.

Opisthorchis felineus, Opisthorchis felineus, etiological therapy, liver fibrosis, malondialdehyde, non-response to treatment