title: Contrast medium-induced nephrotoxicity risk assessment in adult inpatients: a comparison of serum creatinine level- and estimated glomerular filtration rate-based screening methods.
abstract: OBJECTIVE
  To compare serum creatinine (SCr) level- and estimated glomerular filtration rate (eGFR)-based screening methods for identifying adult inpatients at risk for contrast medium-induced nephrotoxicity (CIN).
  
  
  METHODS
  Institutional review board approval was obtained; informed consent was waived for this HIPAA-compliant retrospective study. Computed tomographic examinations performed during 10 years in adult inpatients with stable renal function were identified (n = 28 390). The proportion of inpatients meeting various eGFR (≥60, <60, <45, <30, 30-44, 45-59 mL/min/1.73 m(2)) and SCr (<1.5, ≥1.5, ≥1.6, ≥1.7, ≥1.8, ≥1.9, ≥2.0 mg/dL) thresholds were contrasted with each other and with published guidelines (≥2.0 mg/dL [SCr] and <45 mL/min/1.73 m(2) [eGFR]) using McNemar and binomial tests.
  
  
  RESULTS
  Most inpatients were considered low risk for CIN with commonly used thresholds: 92.6% (26 285 of 28 390) had SCr <1.5 mg/dL; 91.3% (25 922 of 28 390) had eGFR of ≥45 mL/min/1.73 m(2). Using SCr threshold of ≥1.5 mg/dL, identified inpatients had the following eGFRs: 19.6% (413 of 2105), 45-59 mL/min/1.73 m(2); 51.1% (1075 of 2105), 30-44 mL/min/1.73 m(2); 28.6% (603 of 2105), <30 mL/min/1.73 m(2); and 0.7% (14 of 2105), ≥60 mL/min/1.73 m(2) . Using SCr threshold of ≥2.0 mg/dL, identified inpatients had the following eGFRs: 100% (658 of 658), <45 mL/min/1.73 m(2); 74.6% (491 of 658), <30 mL/min/1.73 m(2). Threshold of SCr ≥2.0 mg/dL could not be used to identify eGFR <30 mL/min/1.73 m(2) in 0.4% (112 of 28 390) and <45 mL/min/1.73 m(2) in 6.4% (1810 of 28 390) of all inpatients. Using eGFR <45 mL/min/1.73 m(2) instead of SCr of ≥1.5 mg/dL would result in a significant but small increase in identified inpatients (8.7% [2468 of 28 390; 95% confidence interval: 8.4%, 9.0%] vs 7.4% [2105 of 28 390; 95% confidence interval: 7.1%, 7.7%]; P < .0001).
  
  
  CONCLUSIONS
  Screening using eGFR <45 mL/min/1.73 m(2) instead of common SCr thresholds would significantly increase the number of inpatients identified to be at risk for CIN but would reduce misidentification of a large number of inpatients at low risk according to eGFR criteria.
authors.affiliation: Department of Radiology, University of Michigan Health System, 1500 E Medical Center Dr, Ann Arbor, MI 48103.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Davenport
authors.forename: Shokoufeh
authors.initials: S
authors.lastname: Khalatbari
authors.forename: Richard H
authors.initials: RH
authors.lastname: Cohan
authors.forename: James H
authors.initials: JH
authors.lastname: Ellis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D003287:Contrast Media; D003404:Creatinine / Q000097:blood*; D064420:Drug-Related Side Effects and Adverse Reactions / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D005919:Glomerular Filtration Rate; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D011379:Prognosis; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis* / Q000453:epidemiology*; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003287:Contrast Media; D003404:Creatinine