_id

683a1627c782e11e38d1b222

id

10018

title

AKIN Classification for Acute Kidney Injury (AKI)

full_title

AKIN Classification for Acute Kidney Injury (AKI)

short_title

AKIN Classification

med_description

Classifies severity of acute kidney injury, similar toRIFLE Criteria.

short_description

Acute kidney injury classification.

slug

akin-classification-acute-kidney-injury-aki

description

The AKIN Classification for Acute Kidney Injury classifies severity of acute kidney injury, similar to RIFLE Criteria.

keywords

AKI, acute kidney injury, acute renal failure, AKF, acute kidney failure, glomerular filtration rate, kidney disease, urine output, RIFLE criteria

complaint

[ "Anuria", "Oliguria" ]

formula

To be diagnosed with acute kidney injury by the AKIN definition, patient must have at least one of the following within the past 48 hours: Absolute increase in serum creatinine ≥0.3 mg/dL (≥26.4 μmol/L). Increase in serum creatinine ≥1.5x above baseline. Oliguria (urine output <0.5 mL/kg per hour) for >6 hours. Then, select the appropriate criterion leading to the highest possible stage, e.g. if serum creatinine is normal but urine output is <0.5 mL/kg/hour for >12 hours, AKIN Stage is 2.

evidence

Not all elevations in creatinine represent actual injury to cells within the kidneys.

measurements

[]

information

refrences

{ "Clinical Practice Guidelines": [ { "href": "", "text": "" } ], "Manufacturer Website": [ { "href": "", "text": "" } ], "Original/Primary Reference": [ { "href": "https://ccforum.biomedcentral.com/articles/10.1186/cc5713", "text": "Mehta RL, Kellum JA, Shah SV, et al. Acute Kidney Injury Network: report of an initiative to improve outcomes in acute kidney injury. Crit Care. 2007;11(2):R31." } ], "Other References": [ { "href": "https://cjasn.asnjournals.org/content/1/6/1314.full", "text": "Van biesen W, Vanholder R, Lameire N. Defining acute renal failure: RIFLE and beyond. Clin J Am Soc Nephrol. 2006;1(6):1314-9." } ], "Outcomes": [ { "href": "", "text": "" } ], "Validation": [ { "href": "https://www.ncbi.nlm.nih.gov/pubmed/27818745", "text": "Lopes JA, Jorge S. The RIFLE and AKIN classifications for acute kidney injury: a critical and comprehensive review. Clinical Kidney Journal. 2013;6(1):8-14." }, { "href": "https://www.nature.com/articles/srep17917", "text": "Xiong J, Tang X, Hu Z, Nie L, Wang Y, Zhao J. The RIFLE versus AKIN classification for incidence and mortality of acute kidney injury in critical ill patients: A meta-analysis. Sci Rep. 2015;5:17917." } ], "Validations": [] }

pearls

  • It is important to remember that creatinine is a product of normal muscle cell turnover and serves only as a marker of kidney function.
  • When an elevation in creatinine is observed, the injury that caused it may still be ongoing, but started 24 to 48 hours prior to the increase.
  • The relationship between serum creatinine and eGFR (amount of kidney function) is curvilinear, not linear. Therefore, the same absolute increase in creatinine may represent different severities of AKI depending on the presence or absence of baseline kidney dysfunction.

usecase

Acute kidney injury (AKI) should be suspected if a patient’s serum creatinine rises above their baseline chronic value.

reasons

It is important to recognize when a change in creatinine is clinically significant so that the underlying cause can be identified and further damage prevented.

next_advice

Causes of elevations in creatinine can be grouped into three categories:

  1. Prerenal:

    • Not all elevations in creatinine represent actual injury to cells within the kidneys.  

    • Volume depletion (or effective arterial volume depletion) results in a need to retain sodium and other solutes at the level of the tubule to help support blood pressure.

    • This can be marked by the presence of a low fractional excretion of sodium and can be effectively treated with volume expansion.  

    • While this is often called AKI, it is technically a physiologic response to decreased renal perfusion.

  2. Intrarenal:

    • Intrarenal causes of acute kidney injury include damage to the glomeruli (glomerulopathies) or tubules (acute tubular necrosis or allergic interstitial nephritis).

    • Next steps should include examining the urine to try to determine the location of the injury within the nephron.

  3. Postrenal: Postrenal causes are generally due to obstruction to urine flow at the level of the ureters, bladder, or urethra.

next_actions

  • Management should focus on identifying the cause of kidney injury, determining the need for a kidney biopsy, and reversing all contributing factors to prevent further loss of kidney function.
  • Clinical actions may include correcting volume depletion or hypotension and avoiding medications that can contribute to further kidney injury.

next_management

  • The management of AKI is both supportive and focused on etiology. 
  • While a kidney biopsy is frequently not needed to determine the cause of AKI, it can provide essential information, particularly if a glomerulopathy is suspected as the cause.

diseases

[ "Acute Kidney Injury", "Renal Failure" ]

input_schema

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{ "inct": null, "option_fhir_rules": null, "subheading": "AKI severity", "subheading_instructions": "", "type": "subheading" }

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instructions

Patients on renal replacement therapy (RRT) are considered to be stage 3 regardless of whether they meet formal criteria.

published

2022-04-21T20:28:04.953Z

purpose

[ "Diagnosis" ]

search_terms

[ "acute renal failure", "AKI", "RIFLE", "AKIN", "renal failure", "AKI score" ]

seo

{ "keywords_en": "AKI, acute kidney injury, acute renal failure, AKF, acute kidney failure, glomerular filtration rate, kidney disease, urine output, RIFLE criteria ", "meta_description_en": "The AKIN Classification for Acute Kidney Injury classifies severity of acute kidney injury, similar to RIFLE Criteria." }

specialty

[ "Critical Care", "Family Practice", "Hospitalist Medicine", "Internal Medicine", "Nephrology", "Primary Care" ]

departments

[ "Renal" ]

tags

[]

version_number

1

versions

[]

related

[ { "calcId": 60, "short_title_en": "FENa", "slug": "fractional-excretion-sodium-fena" }, { "calcId": 10019, "short_title_en": "RIFLE Criteria", "slug": "rifle-criteria-acute-kidney-injury-aki" }, { "calcId": 10063, "short_title_en": "Licurse Score", "slug": "licurse-score-renal-ultrasound" } ]

ismed

false

section

[ "whenToUseViewed", "pearlsPitfallsViewed", "whyUseViewed", "nextStepsViewed", "evidenceViewed" ]

cleaned_departments

[ "urology" ]

cleaned_use

[ "Acute kidney injury (AKI) should be suspected if a patient’s serum creatinine rises above their baseline chronic value." ]

pub

false

Criteria for AKI (must have ≥1 within the past 48 hrs)
<p>Absolute increase in serum creatinine &ge;0.3 mg/dL (&ge;26.4 &mu;mol/L)</p>
<p>Increase in serum creatinine &ge;1.5x above baseline</p>
<p>Oliguria (urine output &lt;0.5 mL/kg per hour) for &gt;6 hours</p>
AKI severity
<p>Serum creatinine</p>
<p>Urine output</p>