['Liver-related deaths represent the leading cause of mortality among patients with HIV/HCV-co-infection, and are mainly related to complications of fibrosis and portal hypertension. In this study, we aimed to evaluate the structural changes by the assessment of extracellular matrix (ECM) derived degradation fragments in peripheral blood as biomarkers for fibrosis and portal hypertension in patients with HIV/HCV co-infection.', 'Fifty-eight patients (67% male, mean age: 36.5 years) with HIV/HCV-co-infection were included in the study. Hepatic venous pressure gradient (HVPG) was measured in forty-three patients. The fibrosis stage was determined using FIB4 -Score. ECM degraded products in peripheral blood were measured using specific ELISAs (C4M, MMP-2/9 degraded type IV collagen; C5M, MMP-2/9 degraded type V collagen; PRO-C3, MMP degraded n-terminal propeptide of type III collagen).', 'As expected, HVPG showed strong and significant correlations with FIB4-index (rs\u200a=\u200a0.628; p\u200a=\u200a7*10-7). Interestingly, PRO-C3 significantly correlated with HVPG (rs\u200a=\u200a0.354; p\u200a=\u200a0.02), alanine aminotransferase (rs\u200a=\u200a0.30; p\u200a=\u200a0.038), as well as with FIB4-index (rs\u200a=\u200a0.3230; p\u200a=\u200a0.035). C4M and C5M levels were higher in patients with portal hypertension (HVPG>5 mmHg).'] Do pRO-C3-levels in patients with HIV/HCV-Co-infection reflect fibrosis stage and degree of portal hypertension?