Utility of serum creatinine/cystatin C ratio in diagnosis of postrenal acute kidney injury

• Main Authors: Salih Inal, Atila Altuntaş, Veysel Kidir, Alper Özorak, Yusuf İlgin, Mehmet Tugrul Sezer
• Format: Article
• Language: English
• Published: Wolters Kluwer Medknow Publications 2014-01-01
• Series: Journal of Research in Medical Sciences
• Subjects: Acute kidney injury; creatinine/cystatin C ratio; cystatin C; obstructive uropathy; postrenal acute kidney injury
• Online Access: http://www.jmsjournal.net/article.asp?issn=1735-1995;year=2014;volume=19;issue=11;spage=1086;epage=1089;aulast=Inal

Background: In obstructive uropathy, despite a severe increase in the serum creatinine (Cr) levels, only a mild cystatin C (CysC) increase was previously reported. Therefore, we aimed to determine the availability of serum Cr/CysC ratio in predicting postrenal acute kidney injury (AKI). Materials and Methods: This was a cross-sectional study involving 61-adult patients with heterogeneous AKI cases. Patients with bilateral pelvicalyceal dilatation in renal sonography were considered as postrenal AKI group (n = 15) and others were intrinsic AKI group (n = 46). Venous blood sampling for blood urea nitrogen, Cr and CysC measurements were performed on admission. Results: The mean age of study population was 66.3 ± 15.5 years; 38 (62%) of which were male. Two groups were similar regarding age, gender, and comorbidities. Cr/CysC ratio was significantly higher in postrenal AKI group (6.9 ± 3.1 vs. 4.4 ± 2.1, P = 0.007). Conclusion: We suggest that serum Cr/CysC ratio seems to be a useful diagnostic tool for detection of postrenal AKI cases, especially for the cases without definite hydronephrosis.