A Range of Treatments for Prenatal Kidney Issues

(Submitted by Dr. Amanda C. North, Pediatric Urology at White Plains Hospital)
Unlike conditions of the heart, liver, and other singular organs, most people can live normal lives with just one kidney. However, a condition called prenatal hydronephrosis – essentially the swelling of a kidney in a fetus or infant – may require medical intervention to make sure the developing child is on the right path to good health.

Prenatal hydronephrosis affects between 0.5 to 1% of all pregnancies. The condition is typically brought on by a buildup of urine in the kidney due to a blockage somewhere in the urinary tract – that is, the ureter, urinary bladder, or urethra. The most common type of blockage is a ureteropelvic junction (UPJ) obstruction, involving a blockage where the kidney joins the ureter, which is the thin tube that carries urine to the bladder.

In prenatal cases, hydronephrosis is usually diagnosed during the second trimester via ultrasound. One clue can be low levels of amniotic fluid in the womb; as a fetus’ urine is part of the amniotic fluid, a significantly low level of the latter may indicate that the fetus is not passing enough urine. A swollen abdomen in the fetus can also raise suspicions. In such cases, parents are referred to a pediatric urologist before the baby is born so that they understand and are prepared moving forward.

Usually a sonogram will be given on the newborn within 48 hours of birth; the delay is due to the fact that the amount of fluid in the kidneys depends upon how well hydrated the newborn is. Although hydronephrosis may correct itself, the pediatric urologist will assign a ranking of 1 to 3 to the infant’s situation, with 1 being a minimal case and 3 being a severe one. Persistent mild and moderate cases can often be treated through watchful waiting with or without preventative antibiotics, followed by ultrasounds to measure improvement.

Surgery may be necessary in severe cases, with the aim of reducing the pressure in the kidney by relieving the obstruction. A pyeloplasty, used to address a UPJ obstruction, involves removing the blocked part of the ureter and reconnecting the healthy portion to the kidney’s drainage system.

¬With the less common ureterovesical junction (UVJ) obstruction – a blockage at the point where the ureter joins the bladder – a ureterostomy may be performed. This involves disconnecting the ureter from the bladder and making a surgical incision called a stoma, which drains into a diaper. The ureter will later be re-inserted into the bladder as the baby grows. In older babies and children, the ureter may be reimplanted into the bladder directly without first requiring a ureterostomy.

Depending on the age and general health of the patient, robotic surgery may be an option. In any case, such operations usually take between 1 ½ and 3 hours and have a 97-98% success rate for patients of all ages.

The prospect of surgery for a baby is an emotional and complicated one for any parent. But there are solutions when it comes to prenatal hydronephrosis. Consult with your pediatrician and a pediatric urologist to get the right answers for you and your child.

It is also important to note that hydronephrosis can occur at any age. Severe cases may lead to kidney damage and even kidney failure. Depending on the severity, dialysis or a kidney transplant may be advisable for older patients. The good news is that around 90% of hydronephrosis cases – whether prenatal or postnatal – do not require any intervention; they essentially resolve themselves, or the unaffected kidney does the job of both without any complications.

Dr. Amanda C. North is Chief of Pediatric Urology and an attending physician at the Children’s Hospital at Montefiore (CHAM). To make an appointment, call 914-849-5437.

Health Matters
The original version of this article was published in Health Matters, a White Plains Hospital publication.