From the kidney, urine normally passes through the ureter and drains into the bladder before being flushed out of the body. However, when a blockage occurs at any part of the urinary tract or when there is urine reflux, the kidneys may swell.
Hydronephrosis can be caused by:
Blockages. These can occur:
Where the kidney meets the ureter
Where the ureter meets the bladder
Within the urethra
When the ureter is incorrectly attached to the bladder
Backflow of urine into the kidneys. Also known as vesicoureteral reflux, this happens when urine incorrectly flows from the bladder back up into the kidney. As a result, the kidney does not empty itself, causing it to swell.
Genetic reasons. This can occur with other conditions in the infant.
Unknown reasons. This is known as idiopathic hydronephrosis.
What are the complications and related diseases of hydronephrosis?
Typically, hydronephrosis in children resolve early in life. Even in cases where hydronephrosis does not resolve early, the child can still lead a normal life.
However, there are some cases of hydronephrosis in children that are severe and may lead to complications and other diseases if left untreated. These complications include: