Hydronephrosis

Hydronephrosis is a condition that occurs when kidneys are overfilled with urine because urine drains slower from the kidney to the bladder. Hydronephrosis in a new-born occurs due to the blockage of some part of the urinary tract or reflux of urine from the bladder to the kidney. This causes blockage of the outflow of urine and the kidney appears swollen. The swelling affects one kidney but, in rare cases, both the kidneys can be affected.

Hydronephrosis is of two types:

• Prenatal Hydronephrosis: It is diagnosed in the fetus in the second trimester of pregnancy in ultrasound screening. It occurs because of narrowing of the ureter, blockage in the kidney or bladder, or vesicoureteral reflux that causes the urine to back up into the kidney.
• Antenatal Hydronephrosis: is the most common urological problem that is discovered after birth. It is the fluid-filled enlargement or dilation, of the renal pelvis in the kidney due to the obstruction in the urinary tract. This condition when diagnosed before birth is known as prenatal.

In some cases, hydronephrosis is mild and resolves on its own when the infant is born.

Most infants with hydronephrosis show no symptoms. Older children have the following symptoms depending on the severity of the conditions:

• Pain in the side, back, or abdomen
• Blood in urine
• Swollen abdomen due to due to blockage of urinary tract
• Urinary tract infection
• Frequent urge for urinating
• Nausea and vomiting
• pain in urinating

The root cause of hydronephrosis in an infant is not known. However, Hydronephrosis is commonly occurred due to the obstructions in the urinary tract that blocks the urine flow out of the kidney into the bladder. Some known causes are:

• Transient hydronephrosis occurs because of narrowing of the ureter that generally resolves spontaneously as the infant grows up.
• Blockage/obstruction where ureters join renal pelvis or where the ureter meets the bladder. These are lower urinary tract obstructions and blocks the normal urine flow.
• Some infants have birth defects in the urinary tract or have undeveloped ureters.
• vesicoureteral reflux (VUR) occurs when urine flows backward into the ureters.

Hydronephrosis is usually detected in routine prenatal ultrasound during pregnancy. When the baby is born, the following testing is done to diagnose the condition:

• Renal ultrasound or CT scan is done during the first week after birth, to get a closer look at the swelling area
• A catheter is used to drain the urine from your bladder
• X-ray of the bladder is done to check for vesicoureteral reflux

Treatment of hydronephrosis in new-born depends on the cause of conditions, severity of conditions, and affected part of kidneys.

• Prenatal Hydronephrosis cases are regularly monitored to check the degree of hydronephrosis and its progression
• Mild to moderate hydronephrosis cases are recommended for spontaneous resolution. Periodic monitoring is needed to check for any complications.
• If hydronephrosis gets worse over time, a doctor can remove the obstruction and scar tissue with surgery. It improves the flow of urine.
• If hydronephrosis is caused due to kidney stone, the doctor prefers endoscopic surgery to destroy the stones.
• A nephrostomy tube allowed the blocked urine to drain into the bladder
• Antibiotics can also be prescribed after birth to prevent infection