TIMP1 and coinfection: In HCV monoinfected as well as in HIV/HCV coinfected patients, plasma TIMP-1 levels were correlated with stiffness and discriminated between patients with and without liver fibrosis with both high sensitivity and specificity, raising the possibility of using circulating TIMP-1 as a non-invasive marker of liver fibrosis not only in HCV infection [18,25] but also in HIV/HCV coinfection [26].