title: Performance of creatinine and cystatin C-based glomerular filtration rate estimating equations in a European HIV-positive cohort.
abstract: OBJECTIVE
  To validate glomerular filtration rate (GFR) estimating equations in white HIV-infected patients based on serum creatinine and/or serum cystatin C.
  
  
  METHODS
  Single-center, cross-sectional evaluation of the predictive performance of GFR estimators.
  
  
  METHODS
  GFR was measured by iohexol plasma clearance. Serum creatinine (Scr) and serum cystatin C (Scyst) were measured by traceable and standardized methods. We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations. We also studied the performance of the cystatin C-based equation (CKD-EPI Scyst) and the combined cystatin and creatinine-based equation (CKD-EPI combined), as recently proposed by the CKD-EPI group.
  
  
  RESULTS
  Two hundred and three participants (18% of women) were included. Mean age was 49 ± 10 years. Mean measured GFR (mGFR) was 95 ± 24 ml/min per 1.73 m². CKD-EPI and CKD-EPI combined significantly outperformed the MDRD equation. The percentage of estimating results within 30% of mGFR was 75, 82 and 81% for the MDRD, CKD-EPI and CKD-EPI combined equation, respectively. Results favoring the CKD-EPI and CKD-EPI combined equation were especially observed for patients with mGFR over 90 ml/min per 1.73 m².
  
  
  CONCLUSIONS
  In our European HIV cohort, we confirmed that the creatinine-based CKD-EPI equation should replace the MDRD study equation. However, global performance of this equation remains worse than the performance observed in the general population. This lesser performance is particularly relevant in patients with measured GFR under and around 60 ml/min per 1.73 m². Moreover, the specific interest of Scyst-based equations is not confirmed in this population.
authors: Department of Infectious and Tropical Diseases, CHU Hôpital Nord, Saint-Etienne, France. amandinebrunon@yahoo.fr
authors: Amandine
authors: A
authors: Gagneux-Brunon
authors: Pierre
authors: P
authors: Delanaye
authors: Nicolas
authors: N
authors: Maillard
authors: Anne
authors: A
authors: Fresard
authors: Thierry
authors: T
authors: Basset
authors: Eric
authors: E
authors: Alamartine
authors: Frédéric
authors: F
authors: Lucht
authors: Hans
authors: H
authors: Pottel
authors: Christophe
authors: C
authors: Mariat
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003287:Contrast Media; D003404:Creatinine / Q000097:blood*; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood*; D005060:Europe / Q000208:ethnology; D005260:Female; D005919:Glomerular Filtration Rate; D015658:HIV Infections / Q000097:blood*; D006801:Humans; D007472:Iohexol; D008297:Male; D008875:Middle Aged; D044465:White People; D055815:Young Adult
chemical_list: D003287:Contrast Media; D055316:Cystatin C; D007472:Iohexol; D003404:Creatinine