Acute tubular necrosis

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Evidence last reviewed: 6 Jun 2026

Topic last updated: 30 Jun 2026

Acute tubular necrosis (ATN) is an intrinsic acute kidney injury (AKI) caused by ischemic or nephrotoxic injury to renal tubular epithelial cells with detachment from the basement membrane and consequently, tubular dysfunction.

A history of significant hypotension, fluid depletion, or exposure to nephrotoxic agents is usually present.

In otherwise healthy individuals with normal baseline kidney function, when the underlying insult is corrected, the patient frequently has a good outcome with complete renal recovery within days to weeks.

There is no specific therapy for ATN apart from supportive care.

Definition

AKI is a common syndrome with a wide variety of etiologies and pathophysiologic processes, characterized by a rapid decrease in renal excretory function over a period of minutes to days.[1][2] According to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, AKI severity is classified into three stages depending on the serum creatinine level or the extent of oliguria.[3]

ATN is an intrinsic AKI that follows a condition of severe and persistent hypoperfusion or toxic injury of epithelial cells causing detachment from the basement membrane and tubular dysfunction.[4]

History and exam

Key diagnostic factors

oliguria or anuria
hypotension
tachycardia

Full details

Other diagnostic factors

poor oral intake and anorexia
malaise
thirst
dizziness
orthopnea/dyspnea
edema

Full details

Risk factors

chronic kidney disease (CKD)
chronic hypertension
diabetes mellitus
advanced age
low-perfusion states
sepsis
major surgery
exposure to nephrotoxic agents
exposure to radiocontrast media
exposure to endogenous toxins

Full details

Diagnostic tests

1st tests to order

basic metabolic profile (including BUN and creatinine)
BUN-to-creatinine ratio
urine sodium concentration
urine osmolality
fractional excretion of sodium
fractional excretion of BUN
urinalysis for sediment
CBC
coagulation studies
urinary myoglobin

Full details

Tests to consider

ABG
ultrasound
ECG
inferior vena cava (IVC) diameter measured by ultrasound
kidney biopsy

Full details

Emerging tests

serum and urinary biomarkers

Treatment algorithm

ACUTE

acute tubular necrosis (ATN)

Contributors

Authors

Bernard G. Jaar, MD, MPH

Clinical Director

Johns Hopkins University

School of Medicine

Division of Nephrology

Department of Medicine

Baltimore, MD

Disclosures

BGJ serves as an author for UpToDate (Nephrology) and receives royalties from them.

Acknowledgements

Dr Bernard G Jaar would like to gratefully acknowledge Dr Maria Jesus Lloret Cora, Dr Leonor Fayos de Arizon, and Dr Roser Torra, the previous contributors to this topic.

Disclosures

MJLC, LFdA, and RT declare that they have no competing interests.

Peer reviewers

Ajay Kumar, MD, FACP

Medical Director

Blood Management

Cleveland Clinic

Cleveland, OH

Disclosures

AK has received a fee for speaking about perioperative blood management from Ortho-Biotech, and has also received reimbursement from medscape.com for the education webcast of the same presentation.

Irfan Moinuddin, MD

Assistant Professor

Chicago Medical School

Rosalind Franklin University

Lombard, IL

Disclosures

IM declares that he has no competing interests.

Robert Tompkins, MD

Associate Professor

Department of Family Medicine

University of Texas Health Science Center

Tyler

Disclosures

RT declares that he has no competing interests.

Peer reviewer acknowledgements

BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.

Disclosures

Peer reviewer affiliations and disclosures pertain to the time of the review.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Kidney Disease: Improving Global Outcomes (KDIGO) Acute Kidney Injury Work Group. KDIGO clinical practice guideline for acute kidney injury. Kidney Inter Suppl. 2012 Mar;2(1):1-138.Full text

Gill N, Nally JV Jr, Fatica RA. Renal failure secondary to acute tubular necrosis: epidemiology, diagnosis, and management. Chest. 2005 Oct;128(4):2847-63. Abstract

National Institute for Health and Care Excellence. Acute kidney injury: prevention, detection and management. Oct 2024 [internet publication].Full text

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

Differentials
- Prerenal azotemia
- Intrinsic renal azotemia
- Postrenal azotemia
More Differentials
Guidelines
- KDIGO clinical practice guideline for acute kidney injury
More Guidelines
Log in or subscribe to access all of BMJ Best Practice

Use of this content is subject to our disclaimer

Acute tubular necrosis

Summary

Definition

History and exam

Key diagnostic factors

Other diagnostic factors

Risk factors

Diagnostic tests

1st tests to order

Tests to consider

Emerging tests

Treatment algorithm

acute tubular necrosis (ATN)

Contributors

Authors

Bernard G. Jaar, MD, MPH

Disclosures

Acknowledgements

Disclosures

Peer reviewers

Ajay Kumar, MD, FACP

Disclosures

Irfan Moinuddin, MD

Disclosures

Robert Tompkins, MD

Disclosures

Peer reviewer acknowledgements

Disclosures

References

Key articles

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

Differentials

Guidelines

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

Log in to access all of BMJ Best Practice