PUJO is often first suspected through ultrasonography (USG), which can reveal hydronephrosis—a swelling of the kidney due to urine buildup.
Hydronephrosis, indicated by a renal pelvic diameter ≥ 5 mm, often suggests PUJO.
At NUH, patients with hydronephrosis undergo comprehensive USG to measure the renal pelvis diameter, assess the renal cortex thickness, detect ureteric dilatation and evaluate the opposite kidney and bladder.
A micturating cystourethrogram (MCU) is also performed to rule out vesicouretric reflux.
In many infants with PUJO, hydronephrosis may resolve spontaneously renal function impairment. Therefore, the current approach involves close monitoring and prophylactic antibiotics to prevent urinary infections. Surgical intervention is considered if there is increasing renal pelvic dilatation, cortical thinning or urinary infections due to PUJO.
Surgical intervention
Pyeloplasty is the surgical procedure to correct PUJO. Indications for pyeloplasty include:.
- Pelvic dilatation ≥ 10 mm.
- Obstructive patterns on MAG3 scans.
- Evidence of renal cortex thinning and worsening renal pelvic dilatation on USG.
- Confirmed urinary tract infections.
Historically, the first pyeloplasty was performed in 1891, with the gold-standard dismembered pyeloplasty technique described by Anderson and Hynes in 1949.
Laparoscopic dismembered pyeloplasty was introduced for both adults and children in 1993. While there are no strict criteria for laparoscopic pyeloplasties in children, older children with extrarenal PUJO are considered ideal candidates. Advances in surgical technology, including miniature instrumentation, may enable laparoscopic and potentially robotic pyeloplasties in the future.