Hydronephrosis (swelling in the kidneys) and other kidney defects have been reported in babies who were exposed to Zofran, a popular anti-nausea drug, during pregnancy.
Zofran and Hydronephrosis
An investigative report by the Toronto Star uncovered nearly two dozen reports of Canadian women who had a baby with a birth defect after using Zofran:
“At least 20 Canadian women treated with ondansetron for vomiting in pregnancy experienced serious suspected side-effects, including two infant deaths and multiple cases of newborns with heart defects and kidney malformations.”
The findings are backed up by a number of studies concluding that Zofran increases the risk of major birth defects. One study, published by Australian researchers in 2013, found a 20% overall increased risk of birth defects.
The Australian researchers also found a 6-fold rate of kidney defects, which were reported as “obstructive defects of renal pelvis and ureter.” This description suggests a risk of hydronephrosis, because obstructive defects often cause urine to back up into the kidneys. However, the study was based on only 250 pregnancies involving Zofran, making it too small to draw any conclusions about individual birth defects.
What is Hydronephrosis?
Hydronephrosis is a medical term that means “water in the kidneys.” The syndrome occurs when the kidneys become swollen and distended due to urine backing up inside the kidneys.
Normally, the kidneys are responsible for filtering blood, removing wastes and excess water, and excreting toxins in the urine. When urine backs up, delicate tissues that filter blood can easily become damaged or destroyed.
Left untreated, hydronephrosis can cause permanent kidney damage, organ failure, and infections. The only treatment for kidney failure is a transplant. Without a transplant, kidney failure can be fatal.
Hydronephrosis increases the risk of urinary tract infections, so it is a good idea to be vigilant for symptoms like cloudy urine, painful or weak urination, back pain, and high fever.
Symptoms of hydronephrosis may include:
- Abdominal pain
- Nausea and vomiting
- Painful urination
- Frequent urination
- Urinary tract infections
Congenital hydronephrosis (present at birth) is not uncommon. A growing number of cases are diagnosed before birth via ultrasound. However, just because a baby is born with hydronephrosis does not mean they will have serious problems. Many cases resolve spontaneously without treatment in the first few days of life.
When congenital hydronephrosis does not resolve on its own, there are many treatment options. Obstructions in the ureter (tube that drains urine from the kidneys to the bladder) can be widened with a catheter or propped open with a stent. In severe cases (such as a missing ureter), surgery may be necessary.