title: A comparison of definitions of contrast-induced nephropathy in patients with normal serum creatinine.
abstract: Contrast-induced nephropathy (CIN) is the third leading cause of acute kidney injury in hospitalized patients. The prevalence of CIN is reported to range from 0% to 50%, depending not only on patient condition and the procedure used but also the definition of CIN applied. We aimed to determine the best diagnostic indicator of CIN in patients with normal serum creatinine. This study included 206 patients with normal serum creatinine who underwent coronary angiography/angioplasty. Serum creatinine level and glomerular filtration rate (GFR) were measured before and on the second and fifth days after contrast administration. The incidence of CIN based on a 25% increase in serum creatinine was calculated and compared with the incidence based on a 25% decrease in GFR or an increase of at least 0.5 mg/dL in serum creatinine. Of 206 patients, 127 were male (61.7%) and 79 were female (38.3%); the mean age was 59.56±10.3 years. The prevalence of CIN was 30% based on a 25% increase in serum creatinine, 23% based on a 25% decrease in GFR (P<0.012) and 3.8% based on a serum creatinine increase of at least 0.5 mg/dL (P<0.0001). The serum creatinine levels remained within the normal range in the majority of patients with CIN based on the different definitions. In patients with normal serum creatinine, the absolute increase in serum creatinine may describe the prevalence of CIN more accurately than the relative increase in serum creatinine or relative decrease in GFR.
authors.affiliation: Nephrology Research Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Khatami
authors.forename: Nasrin
authors.initials: N
authors.lastname: Nikravan
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Salari-Far
authors.forename: Safieh
authors.initials: S
authors.lastname: Davoudi
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Pahlavan-Sabbagh
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000139:chemically induced / Q000453:epidemiology*; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D015994:Incidence; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence
chemical_list: D003287:Contrast Media; D003404:Creatinine