High urine IP-10 levels associate with chronic HCV infection

Objectives: Independent of IL-28B polymorphisms, blood IP-10 is a promising biomarker for predicting therapy response in chronic HCV infection. Urine IP-10 has been proposed as a biomarker in tuberculosis, but to date, no urine biomarkers for HCV infection have been evaluated. In this cross-sectional study, we assessed whether IP-10 is detectable in the urine of chronically HCV-infected patients, and if so, whether urine IP-10 correlates with serum IP-10 and HCV-specific clinical parameters.

Methods: IP-10 was measured by ELISA in serum and urine concomitantly taken from 38 HCV-viremic patients, 10 cured-HCV subjects and 11 healthy donors enrolled as controls.

Results: The urine of HCV-viremic patients showed measurable amounts of IP-10, although significantly lower than in serum (p < 0.0001). Urine IP-10 was normalized with creatinuria levels and we found that the urine IP-10/creatinuria ratio was significantly higher in HCV-viremic patients than in cured-HCV subjects (p = 0.002) and healthy donors (p = 0.008), and that it significantly correlated with transaminases (p = 0.01), although the correlation was low. Similarly, the serum IP-10 level significantly associated with HCV-viremic patients (p < 0.0001) and correlated with transaminases (p < 0.0001).

Conclusions: For the first time to our knowledge, we show that IP-10 is detected and increased in the urine of HCV-viremic patients compared to healthy donors and cured-HCV subjects.