Conditions that are often associated with Unilateral Hydronephrosis include:

  • Acute unilateral obstructive uropathy (when urine cannot drain through the ureter)
  • Blockage of a ureter due to scarring, tumor, urinary stones
  • Chronic unilateral obstructive uropathy 
  • Vesicoureteric reflux (backflow of urine from bladder to kidney) 
  • Nephrolithiasis (kidney stones)
  • Hydronephrosis that occurs without a known cause during pregnancy


A person with Hydronephrosis may have no symptoms or may experience: 

  • Abdominal mass
  • Flank pain
  • Nausea and vomiting
  • Urinary tract infection
  • Fever
  • Painful urination (dysuria)
  • Increased urinary frequency
  • Increased urinary urgency


Unilateral Hydronephrosis can be diagnosed with an imaging test such as an MRI, CT, X-ray or ultrasound.


Your treatment may include:

  • A ureteral stent (tube that allows the ureter to drain into the bladder)
  • A nephrostomy tube (allows the blocked urine to drain through the back)
  • Antibiotics for infections

Preventive antibiotics may be prescribed to decrease the risk of urinary tract infections in patients who have long-term hydronephrosis.