Swelling in One or Both Kidneys

Hydronephrosis refers to swelling of a kidney or both kidneys (bilateral hydronephrosis) caused by a backup of urine. Varied diseases and disorders can block the urinary tract that carries urine from the kidney to the bladder. Infection, tumors and birth defects can cause urine to back up into the kidneys.

Doctors sometimes diagnose fetal hydronephrosis in babies in the womb during prenatal imaging exams. Fetal hydronephrosis often goes away without causing serious problems. However, in some instances, it can harm the kidneys. Using ultrasound testing, health practitioners can watch this condition closely throughout pregnancy. Your doctors will determine whether treatment is needed before or after birth.

Your practitioner may refer your child to a pediatric urology specialist at Penn State Health. Our pediatric urologists have advanced expertise in diagnosing and treating these and other urological and renal (kidney) conditions in children of all ages.

Causes of Hydronephrosis

Varied types of conditions can lead to hydronephrosis in newborn. Examples include:

  • Structural defects that prevent urine from draining properly
  • Neurogenic bladder
  • Urinary system birth defects
  • Vesicoureteral reflux (backflow of urine from the bladder to the kidney), which may be caused by a birth defect, enlarged prostate, narrowed urethra (urinary tube) or other conditions
  • Kidney stones in older children

Symptoms, Diagnosis and Outlook

In some instances, hydronephrosis occurs without symptoms. The symptoms of hydronephrosis may include:

  • Abdominal mass (swollen area of the belly)
  • Fever
  • Flank pain (on one side of the body between the upper abdomen and back)
  • Increased urinary frequency or urgency
  • Nausea and vomiting
  • Painful urination
  • Urinary tract infection (UTI)

Diagnosis and Treatment

Health practitioners typically identify hydronephrosis on an imaging test such as:

  • Ultrasound of the abdomen or kidneys
  • Voiding Cysto-Urethrogram (VCUG)
  • Abdominal MRI
  • CT scan of the abdomen or kidneys
  • Kidney scan

Your child’s doctor or other health practitioner will evaluate any related symptoms and schedule imaging or other diagnostic testing. Evaluation may include a referral to a pediatric urology specialist at Penn State Health for diagnosis and treatment recommendations. You can also contact us to schedule an evaluation with a Penn State Health pediatric urologist.

The urologist will determine the cause of hydronephrosis and recommend treatment options such as:

  • Antibiotics to treat infection
  • Placing a stent (tube) through the bladder and ureter, which allows urine to flow into the bladder
  • Surgery to correct the blockage or reflux
  • Surgery to remove the source of blockage, such as a stone or tumor

Hydronephrosis is treatable with early, expert diagnosis and treatment. Without proper evaluation and treatment, it can lead to pain, infection and loss of kidney function.

Our Experts in Care

The experts at Penn State Health Children’s Hospital are committed to providing our pediatric patients with comprehensive and multidisciplinary care.

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Why Choose Penn State Health for Pediatric Urology Care

Our pediatric urology team treats conditions that involve the urinary tract, bladder, kidneys and sex organs (genitalia). We use the latest technology and treatments to help your child. Our physicians and teams offer high-level care across specialties with sensitivity to the unique conditions and concerns of children.

Pediatric Expertise Across Specialties

The pediatric surgeons at Penn State Health have multispecialty training and experience. Doctors are skilled in performing the most intricate and complex procedures in infants, children and adolescents. Areas of expertise include:

  • Dedicated cross-specialty team of caring pediatric experts before, during and after surgery or other treatments and procedures
  • Minimally invasive surgery (sophisticated instruments and surgical procedures with smaller incisions)
  • Neonatal surgery (premature babies and newborns)
  • Pediatric oncology (cancer care)
  • Pediatric surgical innovation (software and device development)
  • Prenatal diagnosis and treatment (for problems with the baby’s development during pregnancy)

Penn State Health Children’s Hospital: Leading the Way

At Penn State Health, children are cared for by teams that are nationally known for pediatric excellence across medical specialties and subspecialties. Penn State Health Children’s Hospital is:

  • Recognized by the American College of Surgeons (ACS) for exceptional surgical care. Our hospital is one of eight in the nation and the only Level 1 Children’s Surgery Center in Pennsylvania as part of the ACS Children’s Surgery Verification Program.
  • Routinely ranked among the best children’s hospitals in the nation because of our focus on patient care, safety and research. U.S. News & World Report has recognized Penn State Children’s Hospital specialties with top rankings.

Our Research and Clinical Trials Drive Better Care

The pediatric specialists at Penn State Health are leaders in clinical science research. We welcome interested volunteers to consider participating in clinical trials. These studies help our scientists:

  • Improve diagnostic techniques
  • Develop better treatments
  • Collaborate with other researchers to advance care

Learn more about Penn State Health clinical trials.

Support Groups

Support groups provide children and their families an opportunity to connect with others in similar situations. Learn more about the support groups offered at Penn State Health Children’s Hospital.

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Find the care your family needs, close to home, at one of our many locations throughout central Pennsylvania.

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