Last reviewed: 12 May 2021
Last updated: 08 Oct 2020



History and exam

Other diagnostic factors

  • nausea and vomiting
  • dysuria, frequency, or urgency
  • flank pain or costovertebral angle tenderness

Risk factors

  • urinary tract infection
  • diabetes mellitus
  • stress incontinence
  • foreign body in urinary tract (e.g., calculus, catheter)
  • anatomic/functional urinary abnormality
  • immunosuppressive state (e.g., HIV, transplantation, chemotherapy, corticosteroid use)
  • pregnancy
  • frequent sexual intercourse
  • mother with urinary tract infection history
  • new sex partner
  • spermicide use
  • age between 18 and 50 years
  • age >60 years

Diagnostic investigations

1st investigations to order

  • urinalysis
  • Gram stain
  • urine culture
  • complete blood count
  • erythrocyte sedimentation rate
  • C-reactive protein
  • procalcitonin
  • blood culture

Investigations to consider

  • renal ultrasound
  • contrast-enhanced spiral computed tomography
  • magnetic resonance imaging

Treatment algorithm


Professor of Medicine

Division of Nephrology

University of California

San Francisco



LAF declares that she has no competing interests.

Dr Lynda A. Frassetto would like to gratefully acknowledge the assistance of Donna M. Frassetto. DMF declares that she has no competing interests.

Peer reviewersVIEW ALL

Attending Urologist

Providence Saint Joseph Medical Center


Assistant Clinical Professor of Urology

Department of Urology

David Geffen School of Medicine at UCLA

Los Angeles



JL declares that he has no competing interests.

Consultant Nephrologist/Lead Clinician

Renal Unit

Glasgow Royal Infirmary

NHS Greater Glasgow and Clyde




RM declares that he has no competing interests.

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