Fetal hydronephrosis

Case contributed by Mostafa El-Feky

Presentation

Routine second trimester scan.

Patient Data

Age: 30 years
Gender: Female

Second trimester scan (at 27 weeks of gestation)

ultrasound

A cephalic fetus, left side anterior, normal liquor, and anterior placenta.

The fetal left kidney is seen enlarged with moderate hydronephrosis and stretched parenchyma. The AP diameter of the renal pelvis measures 15 mm. There is a ballooning of the renal pelvis with no visualized dilated left ureter.

Normal size of the fetal right kidney with minimal pelvicalyceal dilatation (rim like), likely physiological.

Normal urinary bladder.

Follow up study (at 38 weeks of gestation)

ultrasound

A cephalic fetus, left side anterior, normal liquor, and anterior placenta.

The fetal left kidney is more enlarged with moderate hydronephrosis and stretched parenchyma. The AP diameter of the renal pelvis currently measures 32 mm. There is a ballooning of the renal pelvis with no visualized dilated left ureter.

Normal size of the fetal right kidney with minimal pelvicalyceal dilatation, likely physiological.

Normal urinary bladder.

Incidental mild left scrotal hydrocele.

Postnatal ultrasound scan

ultrasound

Grade III left hydronephrosis with stretched renal parenchyma. The AP diameter of left renal pelvis is measuring about 37 mm.

Collapsed right renal pelvicalyceal system.

Case Discussion

This case shows a typical example of prominent fetal hydronephrosis. The dilatation doesn't extend to the ureter and the renal pelvis is ballooned, then pelviureteric junction obstruction is suggested. Postnatal renal ultrasound is recommended for follow-up, as this degree of dilatation could make surgical intervention more proposed management.

Pelviureteric junction obstruction remains the main cause of fetal and neonatal hydronephrosis. It is more common in males. 

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.