If you have hydronephrosis, your symptoms will depend on whether the urine blockage occurred quickly or gradually.
If the blockage forms quickly (acute hydronephrosis) – for example, as a result of a kidney stone, your symptoms will develop over the course of a few hours. If the blockage develops gradually, over a period of weeks or months (chronic hydronephrosis), you may experience few or no symptoms.
The type of symptoms that you will experience will also depend on where the problem is and the length of time that the flow of urine remains blocked. How severe your symptoms are will depend on the extent of the urine blockage and how much your kidney has been stretched.
Acute hydronephrosis
The most common symptom of acute hydronephrosis is a severe pain in your back or side, between your ribs and hip. The pain will be on the side of the affected kidney or on both sides if both kidneys are affected. In some cases, the pain may travel towards the testicles (in men) or vagina (in women).
The pain usually comes and goes and is often worse when drinking fluid. As well as pain, you may also experience nausea and vomiting.
If the urine inside your kidney becomes infected, you will also have symptoms of a kidney infection, such as:
- a high temperature (fever) of 38C (100.4F) or above
- uncontrollable shivering
- diarrhoea
See kidney infection – symptoms for more information.
If the blockage of urine has been caused by a kidney stone, you may notice the presence of blood in your urine. In severe cases of hydronephrosis, one or both of your kidneys may be noticeably swollen to the touch.
Chronic hydronephrosis
If your hydronephrosis is caused by a blockage that develops gradually over a long period of time, you may experience:
- the same symptoms as acute hydronephrosis (see above)
- no symptoms at all
- a dull ache in your side that comes and goes
You might also urinate less often than you used to.
When to seek medical advice
Always contact your GP if you:
- develop a severe and persistent pain
- have symptoms, such as a high temperature, which suggest that you may have an infection
- notice a uncharacteristic change in how often you urinate
