Hydronephrosis is a medical condition characterized by swelling of one or both kidneys due to the buildup of urine. This occurs when urine cannot drain properly from the kidney to the bladder because of a blockage or obstruction in the urinary tract. Without timely treatment, hydronephrosis can damage kidney function and lead to serious health complications.
What Is Hydronephrosis?
In a healthy urinary system, urine flows smoothly from the kidneys through the ureters into the bladder and is passed out of the body. In hydronephrosis, this flow is blocked or slowed, causing urine to back up into the kidney. The kidney stretches and swells, reducing its ability to filter waste from the blood.
Hydronephrosis can affect one kidney (unilateral) or both kidneys (bilateral) and may occur in people of all ages, including newborns.
Common Causes of Hydronephrosis
In Adults
- Kidney stones
- Urinary tract infections (UTIs)
- Enlarged prostate
- Pelvic or abdominal tumors
- Ureteral strictures (narrowing of the ureter)
- Pregnancy-related pressure
In Children and Newborns
- Congenital narrowing of the ureter
- Vesicoureteral reflux (backward flow of urine)
- Posterior urethral valves in boys
Symptoms of Hydronephrosis
Symptoms vary depending on severity and how quickly the blockage develops.
Common signs include:
- Flank or lower back pain
- Abdominal discomfort
- Nausea or vomiting
- Frequent urination
- Painful urination
- Blood in urine
- Fever (if infection is present)
- In infants: feeding difficulties or poor weight gain
Diagnosis of Hydronephrosis
Early detection is vital to prevent kidney damage. Doctors may use:
- Ultrasound – first-line imaging test
- CT scan or MRI – detailed obstruction assessment
- Urinalysis – checks for infection or blood
- Blood tests – evaluates kidney function
Prenatal ultrasound commonly detects hydronephrosis in babies before birth.
Treatment Options
Treatment depends on the underlying cause and the severity of the condition.
Mild Cases
- Careful monitoring
- Increased fluid intake
- Management of infections
Moderate to Severe Cases
- Medications to treat infection or relieve symptoms
- Ureteral stent placement to allow urine flow
- Nephrostomy tube insertion to drain blocked urine directly from the kidney
- Surgical correction of the obstruction (e.g., stone removal or repair of narrow ureters)
Prevention of Hydronephrosis
While not always preventable, these measures can help reduce risk:
- Stay well hydrated
- Treat UTIs promptly
- Manage prostate problems under medical guidance
- Maintain kidney stone prevention strategies
- Attend regular health checkups
Complications of Untreated Hydronephrosis
If untreated, hydronephrosis may lead to:
- Chronic kidney disease
- Permanent kidney damage
- Recurrent urinary infections
- Sepsis in severe infection cases
Early diagnosis significantly reduces the risk of long-term complications.
Living With Hydronephrosis
Many patients recover fully once the underlying blockage is treated. Regular follow-up imaging and blood tests may be required to ensure kidney health remains stable.
In children with congenital hydronephrosis, careful observation often leads to natural resolution over time without surgical intervention.
When to Seek Medical Attention
Consult a doctor immediately if you experience:
- Persistent side or back pain
- Fever with urinary symptoms
- Blood in urine
- Reduced urine output
Prompt treatment protects kidney function and prevents complications.
Final Thoughts
Hydronephrosis is a serious but treatable condition when identified early. With proper diagnosis, timely treatment, and consistent follow-up care, most individuals lead healthy lives without long-term kidney problems. Awareness of symptoms and seeking medical help quickly are key to protecting your kidneys.
