Comparative study of various glomerular filtration rate estimating equations in Egyptian patients with hepatitis C virus-related liver cirrhosis: a single-center observational study

Abstract

Abstract Background Accurate assessment of GFR is critical in patients with chronic liver disease for early detection of renal disease. Cystatin C is a marker of GFR that seems to be more accurate than creatinine. The aim of the study is to assess of the performance of creatinine and cystatin C-based GFR equations in Egyptian patients with hepatitis C virus (HCV)-related liver cirrhosis as compared to measured creatinine clearance. GFR was estimated using five equations; three that were based on serum creatinine, another that was based on serum cystatin C, and a third that was based on both in 120 patients with HCV-related liver cirrhosis as well as 60 age- and sex-matched healthy controls. The bias, precision, and accuracy of each equation were determined as compared to measured creatinine clearance using the traditional equation U*V/P. Results The mean measured creatinine clearance was 51.39 ± 16.05 ml/min per 1.73 m2. The CKD-EPI creatinine-cystatin C equation had the greatest precision (7.5 ml/min per 1.73 m2), and highest accuracy (68 and 93% within 10% and 30% of measured GFR, respectively), but not the lowest bias (5.4 ml/min per 1.73 m2). The CKD-EPI creatinine-cystatin C equation remained accurate even in both males (69 and 90% within 10% and 30% of measured GFR, respectively) and females (68 and 97% within 10% and 30% of measured GFR, respectively). The CKD-EPI creatinine-cystatin C equation remained accurate even when the measured GFR was ≥ 60 ml/min per 1.73 m2 (60 and 90% within 10% and 30% of measured GFR, respectively with precision 10.5 ml/min per 1.73 m2). Conclusion CKD-EPI creatinine-cystatin C equation is more accurate at predicting GFR in HCV-related liver cirrhosis than creatinine- and cystatin-C alone based equations.