15417 Hydronephrosis

Overview

Hydronephrosis is a condition where one or both kidneys become swollen because urine is trapped and can't flow out as it should. The buildup of urine stretches the kidney, and if left untreated, it may cause damage.

Hydronephrosis is not very common in the general population, but it can happen at any age. It is often discovered when a scan is done for another reason.

It can affect anyone, from unborn babies to older adults. In children, it is often present from birth. In adults, it is more likely to be linked to kidney stones, pregnancy, or an enlarged prostate.

Symptoms

Common symptoms

• Pain in the side, back, or belly
• Pain or burning when urinating
• Feeling the need to urinate often or urgently
• Nausea and vomiting
• Fever
• Swelling in the belly or side

Symptoms in children

• Fever without an obvious cause
• Poor feeding or vomiting
• A lump in the belly
• Poor weight gain

Symptoms in older adults

• Older adults may not have typical symptoms, or they may become confused
• Fever and chills
• Changes in urination, such as going less often or straining to pass urine

Causes

Main causes

• A blockage in the urinary tract, such as a kidney stone, an enlarged prostate, or a tumour
• Vesicoureteral reflux — a condition where urine flows backwards from the bladder towards the kidneys
• Pregnancy, because the growing womb can press on the tubes that carry urine
• A narrowing (stricture) in the ureter, which is the tube between the kidney and the bladder

Risk factors

• Having had kidney stones before
• Having had surgery on the urinary tract
• Being pregnant
• Being a man with an enlarged prostate
• Having a child with a congenital urinary tract problem

When to see a doctor

See a doctor urgently if:

• If you have severe pain, fever, chills, vomiting, or cannot pass urine, you need urgent care. Call your local emergency number right away.
• If you have blood in your urine along with pain, seek urgent medical help.

Book a routine appointment if:

• If you have a dull ache in your side or back, a frequent need to urinate, or discomfort when urinating that does not go away, book an appointment with your GP.
• If you have already been diagnosed and notice new symptoms, let your doctor know.

Diagnosis

Doctors usually diagnose hydronephrosis using imaging tests that create pictures of your kidneys and urinary tract.

Tests that may be done

• Ultrasound — the most common and painless test that uses sound waves to see the kidneys
• CT scan — a detailed scan that can find blockages or stones
• MRI scan — used in specific situations, especially in pregnancy or in children
• Urine and blood tests — to check for infection or kidney function
• A cystoscopy — a thin tube with a camera to look inside the bladder, sometimes used by a specialist

What to expect at your appointment

You will probably have a physical exam and a discussion about your symptoms. The ultrasound is painless and takes about 15–30 minutes. You may be referred to a kidney specialist (nephrologist) or a urinary tract specialist (urologist) for further tests and treatment.

Treatment

Treatment depends on the cause and how much the kidney is swollen. The goal is to relieve any blockage, treat any infection, and protect your kidneys. Some cases resolve on their own without treatment.

Self-care at home

• Drink plenty of water if your doctor says it is safe for you
• Take over-the-counter pain relief only if your doctor approves
• Rest and avoid heavy lifting
• Apply a warm compress to your back or side for comfort
• Avoid alcohol and caffeine if they make your symptoms worse

Medical treatments

Doctors may use a procedure to drain the urine, such as placing a thin tube called a stent inside the ureter, or a catheter through the bladder. They may also treat the underlying cause, such as removing a kidney stone or giving antibiotics for an infection. Any medicines will be prescribed by your doctor based on your specific situation.

When is surgery considered?

Surgery may be needed if the blockage is persistent, severe, or caused by a structural problem. The type of surgery depends on the cause and your overall health. Your specialist will explain the options and what to expect.

Living with this condition

After treatment, you may need regular check-ups so your doctor can make sure your kidneys are working well. Many people feel much better once the blockage is relieved. Keep an eye on your symptoms and report any changes.

Lifestyle tips

• Follow your doctor's advice about how much fluid to drink
• Try not to hold in your urine — go when you feel the need
• Maintain a healthy weight
• Do not smoke, as it can harm your kidneys and overall health

Diet and exercise

A balanced diet and regular exercise are good for your general health. If you have kidney problems, your care team may give you specific advice about salt, protein, or potassium. Always ask them before making major diet changes.

Mental health and emotional wellbeing

Living with a kidney condition can be worrying. It is normal to feel anxious or stressed at times. Talking to friends, family, or a counsellor can help. If you are struggling, speak to your GP — they can point you towards helpful resources.

Prevention

Not always, because many causes of hydronephrosis cannot be prevented. But you can reduce the risk of kidney stones by staying well hydrated, and you can manage conditions like an enlarged prostate with your doctor's help.

Screening programmes

There is no routine screening for hydronephrosis, but if you have a known risk, such as a congenital condition or a history of bladder or prostate problems, your doctor may recommend regular ultrasound checks.

Complications

If left untreated

• Permanent kidney damage or kidney failure
• Increased risk of urinary tract infections
• Scarring of the kidney tissue

Long-term outlook

Most people with hydronephrosis improve with treatment. When it is caught early, the kidney can often heal completely. Even if some damage has already happened, treatment can slow or stop further damage and help preserve kidney function. Your healthcare team will support you at every step.

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