Background and study aim: Still there is percentage of HCV patients not responding to Direct Acting Antiviral Agents (DAAS), even the responder HCV patients need to follow up. Gut flora (Microbiota) include all the microorganisms in the intestine and liver can be greatly affected by changes in gut microbiota. The study was done to evaluate the association between gut flora and the response to DAAS in chronic HCV patients.
Methodology: Two groups; group 1 (No=15 of HCV responders patients) and group 2 (No=15 non responder HCV patients) treated by DAAS according to the treatment protocol of the Egyptian National Committee for Control of Viral Hepatitis (NCCVH). Healthy control subjects (No=15)age  and sex matched to the study groups as third group. All investigations were done plus stool culture using VITEK 2 KITS according to the manufacturer.
 
Results: The results show statistically significant difference between the patients (responders and non responders) and control, where p1 comparison between control and responders, p2 between control and non responders, p3 between responders and non responders. Enterobacter organism in p2, p3 was Clostridium perfringens in p2 was 0.009 and 0.04 respectively. Klebsiella organism in p1 and p2 was 0.04 and 0.01 respectively while Streptococci in p2 was 0.007.
Conclusion: Gut microbiota have a crucial role in HCV patients especially the non responders compared to the control even the responders need to be followed up to adjust the gut flora of them to the normal because this proved to play an important role in micro environmental changes that lead to hepatocellular carcinoma (HCC).