View source for Contrast-associated acute kidney injury

== Background ==

* Risk based on eGFR[[CiteRef::solomon2008co]]
** eGFR >45 mL/min: 2%
** eGFR <60 mL/min: 5%

== Clinical Manifestations ==

* Presents with [[AKI]] following administration of CT contrast dye, usually non-oliguric
* Increase in serum creatinine usually seen 24 to 48 hours after infusion
* Urine microscopy may show findings of [[acute tubular necrosis]] with muddy brown casts, epithelial casts, and free renal tubular epithelial cells

=== Prognosis ===

* Usually only causes mild AKI that generally starts to recover within 3 to 7 days, with eventual return to baseline renal function
* Rarely progresses to dialysis

== Differential Diagnosis ==

* Renal atheroembolism (with intraarterial contrast)
* Ischemic [[acute tubular necrosis]]
* [[Acute interstitial nephritis]]
* Prerenal changes related to medication adjustments
* Other causes of [[acute kidney injury]]

== Management ==

* Managed similarly for all AKI
** Stop nephrotoxic medications such as [[aminoglycosides]], [[vancomycin]], [[non-steroidal anti-inflammatory drugs]], [[angiotensin-converting enzyme inhibitors]], and [[angiotensin receptor blockers]]
** Optimize hemodynamics and volume status
** Closely monitor kidney function and fluid balance
** Avoid hyperglycemia
** Avoid further exposure to contrast agents
** Avoid gelatins, colloids, and chloride-rich solutions

== Prevention ==

* Prophylaxis with preinfusion of saline is common but the only RCT to date showed no benefit[[CiteRef::vandenberghe2019co]]
* The evidence in favour of [[N-acetylcysteine]] is similarly poor

== Further Reading ==

* Contrast-associated acute kidney injury: does it really exist, and if so, what to do about it? ''F1000Res''. 2019;8:F1000 Faculty Rev-753. doi: [https://doi.org/10.12688/f1000research.16347.1 10.12688/f1000research.16347.1]