title: Pitfall in nephrology: contrast nephropathy has to be differentiated from renal damage due to atheroembolic disease.
abstract: BACKGROUND
  The topic of contrast-induced nephropathy (CIN) has been receiving an enormous amount of interest in recent times; however, this review is not a review of what CIN is, but what it is not.
  
  
  METHODS
  We will review the main topics demonstrating that the post hoc ergo propter hoc assumption that renal impairment occurring after contrast medium (CM) infusion is necessarily because of it, is wrong, as we are dealing with different diseases, depending on the way the CM is administered and on the type of patient.
  
  
  RESULTS
  After >1,000 often repetitive papers, we must deal with an unacceptably wide range of incidences of CIN, with completely different prognoses and astonishingly conflicting results regarding the efficacy of preventive measures with the exception of hydration. So what went wrong? How to separate tares from wheat? When years ago we challenged the diagnosis of CIN, the words cholesterol embolism had never appeared in this setting. Now, we can split the possible renal dysfunctions following CM administration into CM-related hemodynamic and/or tubular damage, cholesterol embolism, ischemia from acute blood loss or hypotension/hypoperfusion and nephrotoxicity from concomitant drugs.
  
  
  CONCLUSIONS
  In a setting regarding millions of patients and millions of dollars/year, in order to clarify the true renal damage directly related to CM, we ask for prospective studies differentiating cohorts receiving intravenous and intra-arterial, transradial and transfemoral injections, and clinically relevant renal outcomes, thus avoiding the dangers that can come from the idolatry of a surrogate end point such an asymptomatic 25% transient increase of serum creatinine. To avoid that, patients may lose the possibility of a more useful radiological diagnosis, because of an exaggerated suspicion of risk.
authors.affiliation: Division of Nephrology and Urology, Department of Translational Medicine, Amedeo Avogadro University, Novara, Italy. piero.stratta@med.unipmn.it
authors.forename: Piero
authors.initials: P
authors.lastname: Stratta
authors.forename: Cristina
authors.initials: C
authors.lastname: Bozzola
authors.forename: Marco
authors.initials: M
authors.lastname: Quaglia
mesh_terms: D003287:Contrast Media / Q000009:adverse effects*; D017700:Embolism, Cholesterol / Q000150:complications*; D006801:Humans; D007668:Kidney / Q000473:pathology*; D007674:Kidney Diseases / Q000145:classification / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors; D009626:Terminology as Topic
chemical_list: D003287:Contrast Media