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Last reviewed: 20 Apr 2025
Last updated: 24 Apr 2025

Summary

Definition

History and exam

Key diagnostic factors

  • history of vesicoureteral reflux (VUR)
  • history of acute pyelonephritis
  • history of renal obstruction

Other diagnostic factors

  • female sex
  • nausea
  • elevated blood pressure
  • children and infants (risk of VUR)
  • adults (risk of XGP and EPN)
  • weight loss
  • fatigue
  • malaise
  • cloudy urine
  • fever
  • back/flank pain and tenderness

Risk factors

  • neurogenic bladder
  • acute pyelonephritis
  • vesicoureteral reflux
  • obstruction
  • renal calculi
  • diabetes mellitus

Diagnostic investigations

1st investigations to order

  • urinalysis
  • renal function
  • urine culture
  • electrolyte panel
  • FBC
  • renal ultrasound
  • kidney-ureter-bladder (KUB) x-ray
  • CT abdomen

Investigations to consider

  • MRI abdomen
  • voiding cystourethrography (VCUG)
  • renal biopsy

Treatment algorithm

ONGOING

Contributors

Authors

Lynda A. Frassetto, MD

Professor of Medicine

Division of Nephrology

University of California

San Francisco

CA

Disclosures

LF declares that she has no competing interests.

Acknowledgements

Dr Frassetto would like to gratefully acknowledge the assistance of Donna M. Frassetto.

Disclosures

DMF declares that she has no competing interests.

Peer reviewers

Bernard G. Jaar, MD, MPH

Clinical Director

Johns Hopkins School of Medicine

Division of Nephrology

Baltimore

MD

Disclosures

BGJ declares that he has no competing interests.

Farah Abifaraj, MD

Clinical Associate

Johns Hopkins School of Medicine

Division of Nephrology

Baltimore

MD

Disclosures

FA declares that she has no competing interests.

James Marsh, MA FRCP

Consultant Nephrologist and Clinical Director

Renal Unit

St Helier Hospital

Carshalton

Surrey

UK

Disclosures

JM declares that he has no competing interests.

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

Vourganti S, Agarwal PK, Bodner DR, et al. Ultrasonographic evaluation of renal infections. Radiol Clin North Am. 2006 Nov;44(6):763-75. Abstract

Gupta K, Hooton TM, Naber KG, et al. International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: a 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis. 2011 Mar 1;52(5):e103-20.Full text  Abstract

American Urological Association. Management and screening of primary vesicoureteral reflux in children (2010, amended 2017). 2021 [internet publication].Full text

Reference articles

A full list of sources referenced in this topic is available here.

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