Hydronephrosis—Child
Condition
Definition
Hydronephrosis is when one or both kidneys swell with backed up urine. This swelling can lead to kidney infection or kidney harm.
Hydronephrosis is a symptom of another health issue.
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Causes
Hydronephrosis is caused by urinary tract problems that make it hard for urine to leave the kidneys. Urine may be slowed or stopped by:
- A blockage, bulge, or narrowing in the tube that carries urine from the kidney to the bladder
- In boys, flaps of tissue blocking the tube that carries urine out of the body or narrowing of the tip of the penis
Other health issues that may cause problems include:
- Urine flowing backward from the bladder into the kidneys
- Problems with the tube that carries urine to the bladder or in the way that it connects
- An abnormal kidney may sometimes cause problems
Children are often born with one of these health issues that affect the urinary tract. For some, the problem appears later on. Sometimes the cause of hydronephrosis is not known.
Risk Factors
Hydronephrosis is more common in boys than girls.
Symptoms
A child with hydronephrosis may have:
- Pain in the back, sides, belly, or groin
- Blood in the urine
- Trouble feeding
- Poor growth
- Signs of urinary tract infection
- Urine that has a strong smell
- Vomiting
- Fever
- Blood in the urine
- Irritability
Diagnosis
Most often hydronephrosis is diagnosed during an ultrasound before the child is born.
After birth the doctor will ask about symptoms and health history. A physical exam will be done. A swollen kidney may be able to be felt at the physical exam.
Urine tests and blood tests may be done.
Imaging tests may be done to look for blockages and other problems. These tests may include:
- Ultrasound—may be done before and after birth
- Voiding cystourethrogram—x-rays of the bladder and urethra taken during urination that are only done if hydronephrosis is still an issue after birth
- MRI scan
- CT scan
- Cystoscopy
Treatment
Hydronephrosis that starts before birth will often go away on its own without hurting the kidney. It may go away before or after birth. A child's kidneys will be watched until the swelling has gone away.
A health issue that is causing the urine backup will be treated. Treatment options may include:
Prevention
Hydronephrosis cannot be prevented.
Medicine
The doctor may advise:
- Over the counter medicine to reduce pain or fever
- Antibiotics to prevent or treat an infection
Medicine
The doctor may advise:
- Over the counter medicine to reduce pain or fever
- Antibiotics to prevent or treat an infection
Surgery
- The hydronephrosis is causing a lot of pain
- There are signs of kidney damage
- There is a problem such as a blockage that will not go away on its own
American Kidney Fund
National Kidney Foundation
CANADIAN RESOURCES:
BC Children’s Hospital
The Kidney Foundation of Canada
American Kidney Fund
National Kidney Foundation
CANADIAN RESOURCES:
BC Children’s Hospital
The Kidney Foundation of Canada
References
- Hydronephrosis. Boston Children’s Hospital website. Available at: https://www.childrenshospital.org/conditions/hydronephrosis.
- Hydronephrosis. University of California Davis Health System website. Available at: http://www.ucdmc.ucdavis.edu/urology/downloads/kurzrock_handouts_PDF/Hydronephrosis.pdf.
- Hydronephrosis. University of California San Francisco Benioff Children's Hospital website. Available at: http://www.ucsfbenioffchildrens.org/conditions/hydronephrosis.
- Värelä, S., Omling, E., et al. Resolution of hydronephrosis after pyeloplasty in children. Journal of Pediatric Urology, 2021; 17 (1): 102.E1-102.E7.
- Vesicoureteral reflux. EBSCO DynaMed website. Available at: http://www.dynamed.com/condition/vesicoureteral-reflux-vur.
Contributors
- Chelsea Skucek, MSN, BS, RNC-NIC
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