1. evaluation of glomerular filtration rate(eGFR)changes during HCV treatment with direct antiviral drugs according to 2018 guideline.
2. TO estimate the frequency of renal impairment by direct antiviral drugs By detection of any changes in e GFR.
3. Assessment The Renal safety during HCV treatment with direct antiviral drugs according to 2018 guideline.
4. To clarify the importance of laboratory and other modalities in detection and estimation of frequency of renal impairment by direct antiviral drugs according to 2018 guideline.

Hepatitis C virus (HCV) has an estimated global prevalence of 2%-3% with 130-170 million people infected with HCV.(1) HCVcauses chronic inflammation of the liver leading to chronic hepatitis, which can advance to liver cirrhosis and hepatocellular carcinoma and significant extrahepatic complications.(2) Additionally, HCV has been shown to have a significant negative effect on apatient's overall quality of life, including decreased work hours and productivity and increased healthcare costs.(3) Cirrhosis and hepatocellular carcinoma related to HCV infection represent the most common indications for liver transplantation duo to poor treatment options.(4) Until recently, interferon-based treatments were thebackbone of HCV treatment options.(5) Unfortunately,therapy was only modestly effective and associatedwith significant side effects.(6) Therefore, research has focused on HCV eradication using oral antiviral therapy.

Recent clinical studies have demonstrated efficacy using the nucleotide analogue inhibitor sofosbuvir(Sovaldi; Gilead Sciences, Inc., Foster City, CA) as the backbone in treatment of non transplant and post transplant recurrent HCV.(7) Both the ION-1 and ION-2 trials demonstrated nearly 99% efficacy in the treatment ofnontransplant, noncirrhotic HCV patientsusing sofosbuvir in a fixed-dose combination with theNS5A inhibitor ledipasvir (Harvoni, Gilead Sciences,Inc.), both with and without ribavirin.(8,9) The side effect profile of ledipasvir/sofosbuvir (LDV/SOF) hasbeen relatively mild and the drug has been well tolerated in trials, especially compared with previous interferon-based regimens.

The ION trials report that LDV/SOF therapy was primarily complicated by headaches or fatigue inapproximately 10% of patients. Less frequently, patients experienced rashes, nausea, diarrhea, and insomnia.Serious side effects, such as nephrotoxicity, were not demonstrated by the ION-1 and ION-2 trials; however, these trials were conducted in a controlled clinical setting with rigorous exclusion criteria. Such trials are not always entirely reflective of the general patient population. Early data suggest possible risk of renal impairment during treatment with the use of direct antiviral drugs(10) this study is about renal safety and changes in eGFR in patients with chronic HCV undergoing direct acting antiviral therapy according to 2018 guideline.

Inclusion Criteria:

• chronic hepatitis C virus patients will be on direct antiviral therapy .

Exclusion Criteria:

• patients with DM ,HTN ,CKD,Autoimmune Diseases Patients with kidney injury other than DAAs Patients with sever heart failure or malignancy

chronic hepatitis C virus patients will be on direct antiviral therapy attending to the outpatient clinics and inpatient of gastroenterology units of Internal medicine department .