Obstructive uropathy

Last reviewed: 30 Aug 2023
Last updated: 09 Feb 2021



History and exam

Key diagnostic factors

  • signs of early organ dysfunction (tachypnea, tachycardia, hypotension, altered mental state) in a patient with suspected sepsis
  • flank pain
  • fever
  • lower urinary tract symptoms
  • distended abdomen/palpable bladder
  • inability to urinate
  • enlarged or hard nodular prostate on rectal examination
  • costovertebral angle tenderness
  • neurologic disease (e.g., spinal cord injury, multiple sclerosis)
More key diagnostic factors

Other diagnostic factors

  • hematuria
  • increasing age
  • meatal narrowing
  • pelvic or abdominal malignancy
  • previous urethral instrumentation
  • urinary tract infection in a child
  • pelvic mass on internal examination
  • weight loss and lymphadenopathy
  • recurrent urinary tract infections
  • urinary incontinence
Other diagnostic factors

Risk factors

  • benign prostatic hyperplasia (BPH)
  • constipation
  • medication (anticholinergic agents, narcotic analgesia, alpha receptor agonists)
  • urolithiasis (ureteric calculi)
  • spinal cord injury, Parkinson disease, or multiple sclerosis
  • malignancy
  • pregnancy
  • hematuria
  • posterior urethral valves
  • bladder hernia
  • cystocele
  • iatrogenic injury
  • urethral instrumentation
  • retroperitoneal fibrosis
  • meatal stenosis
More risk factors

Diagnostic investigations

1st investigations to order

  • urinary dipstick
  • renal ultrasound
  • serum BUN and creatinine
  • CBC
  • CT pyelogram
  • intravenous pyelogram (excretory urography)
More 1st investigations to order

Investigations to consider

  • urine culture
  • blood culture
  • CT scan abdomen and pelvis
  • magnetic resonance urography
  • nuclear renography (triple renal/MAG3 scan)
  • voiding cystourethrogram
  • bladder ultrasound
  • prostate specific antigen
  • tumor markers (e.g., serum carcinoembryonic antigen [CEA], CA125)
More investigations to consider

Treatment algorithm


unilateral or bilateral obstruction with signs of infection


unilateral or bilateral obstruction due to calculi without signs of infection

unilateral obstruction not due to calculi without signs of infection

bilateral obstruction not due to calculi without signs of infection



Adrienne J. Carmack, MD


Integrative Health Matters




AJC declares that she has no competing interests.

Peer reviewers

Brian Cohen, MD

Private Practice Urologist




BC declares that he has no competing interests.

Yekutiel Sandman, MD

Private Practice Urologist




YS declares that he has no competing interests.

Vincent Gnanapragasam, MBBS, BMedSci, PhD, FRCSEng, FRCSEd(Urol)

Lecturer in Uro-oncology and Consultant Urological Surgeon

Department of Urology

Addenbrooke's Hospital




VG declares that he has no competing interests.

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