Causes of a swollen kidney

Many people may not realize this but our kidneys can swell and when they do it is a condition called hydronephrosis. If urine is unable to drain out from the kidney to the bladder, it can cause the kidneys to swell leading to a build-up of urine.  This condition can occur in either one or both kidneys and happens as the result of a disease.

Throughout the day, the bladder slowly fills up with urine emptying from the kidneys down tubes connecting each kidney to the bladder called ureters.  The condition of hydronephrosis occurs when there is either a blockage of the outflow of urine or reverse flow of urine already in the bladder called reflux. 

Symptoms of hydronephrosis

Hydrohephrosis may or may not cause symptoms depending on the cause and severity of the urinary blockage.  If there are symptoms, the most common include:

·Flank pain

·Abdominal mass

·Pain during urination

·Increased urge or frequency of urination

·Incomplete urination or incontinence

·Nausea and fever

·Urinary tract infection

Causes of hydronephrosis

Generally there is an underling illness that causes this condition.  The causes of it include but are not limited to, the following illnesses or risk factors:

·Kidney stone

·Congenital blockage – a defect present at birth

·Blood clot

·Scarring of tissue from an injury or previous surgery

·Back flow of urine from bladder to kidney called reflux

·Problems with the nerves that supply the bladder

·Cancers or tumors that occur in the pelvis or abdomen

·Blockage from an enlarged uterus during pregnancy

·Enlarged prostate

How is hydronephrosis diagnosed?

The main way to diagnosis this condition is typically by an ultrasound.  Ultrasounds are a painless procedure using waves to create an image of the kidneys to help confirm the diagnosis.  There are other ways a doctor may choose to confirm this condition such as x-rays, computerized tomography (CT scan) and magnetic resonance imaging (MRI).  A cystoscopy may also be used – this procedure uses a long tube with a light and camera at the end (cystoscope) allowing a doctor to look inside the bladder and urethra.

In addition, blood and urine test can also be of value to assess kidney function. 

Treating hydronephrosis

To treat hydronephrosis, the underlying causes of why it is occurring must first be figured out.  Depending on what the cause may be, will determine what method of treatment will be necessary.  If it is an infection, it most likely will be treated with an antibiotic.  If there is a kidney stone, hopefully they will pass on their own but if not, then it may require surgery. 

If there is a severe blockage, to prevent an infection or worse, excess urine may need to be removed using either a catheter to drain urine from the bladder or a tube called a nephrostomy may be used to drain urine from the kidney.  It is important to address the problem as soon as possible in order to avoid any permanent damage to the kidneys.

The worst case scenario could be that of left untreated or if there is a severe urinary blockage, this could damage the kidneys leading to kidney failure.  Kidney failure is rare if the other kidney is working normally.  However, kidney failure will occur if there is only one functioning kidney.  If this were to occur, the treatment then would be either dialysis or a kidney transplant. 

In most cases of hydronephrosis, the vast majority of people do recover from this condition if it is treated promptly.