From the Guidelines
Infants with pelviectasis should be followed up with ultrasound examinations at regular intervals, with the frequency based on the severity of the condition, as outlined in the most recent guidelines from the Society for Maternal-Fetal Medicine 1.
Key Considerations
- The severity of pelviectasis is classified based on the anterior-posterior renal pelvis diameter, with <4 mm being normal between 16 and 27 weeks of gestation and <7 mm being normal between 28 weeks of gestation and delivery 1.
- For fetuses with isolated UTD A1, an ultrasound examination at ≥32 weeks of gestation is recommended to determine if postnatal pediatric urology or nephrology follow-up is needed 1.
- For infants with mild pelviectasis, follow-up ultrasounds are recommended at 1-3 months of age and again at 6-12 months of age.
- For infants with moderate pelviectasis, more frequent monitoring is advised with ultrasounds at 1 month, 3 months, and 6-12 months of age.
- Severe cases require closer surveillance with ultrasounds at 1 month, 3 months, 6 months, and 12 months of age.
Additional Recommendations
- Prophylactic antibiotics such as amoxicillin (10-15 mg/kg/day) or trimethoprim-sulfamethoxazole (2 mg/kg/day of the trimethoprim component) may be prescribed for moderate to severe cases to prevent urinary tract infections until the condition resolves or further intervention is determined necessary.
- The American Urological Association recommends annual monitoring of blood pressure, height, and weight, as well as urinalysis for proteinuria and bacteriuria, for children with vesicoureteral reflux 1.
- Ultrasonography is recommended every 12 months to monitor renal growth and any parenchymal scarring, while voiding cystography (radionuclide cystogram or low-dose fluoroscopy) is recommended every 12 to 24 months 1.
From the Research
Follow-up Frequency for Pelviectasis in Infants
The recommended follow-up frequency for pelviectasis (pelvic ectasis) in infants is not explicitly stated in the provided studies. However, the studies suggest the following:
- Infants with mild postnatal renal dilatation can be investigated with only one further sonogram at 24 months of age 2.
- Renal pelvis diameter (RPD) normalization typically occurs within 1 year of birth, whether vesicoureteric reflux (VUR) is present or not 3.
- Follow-up renal ultrasonography can be performed to monitor the resolution or improvement of extra-renal pelvis (ERpel) in neonates, with some studies suggesting a follow-up period of 2 years 4.
Key Findings
- The majority of infants with pelvic ectasia have a benign course, with resolution of the condition within the first year of life 5, 3.
- The presence of VUR or other urinary tract abnormalities does not necessarily correlate with the degree of pelvic ectasia 5, 3.
- Infants with ERpel are at a higher risk of developing urinary tract infections (UTIs), even in the absence of VUR 4.
Diagnostic Evaluation
- Voiding cystourethrography (VCUG) and renal ultrasound are commonly used diagnostic tools to evaluate infants with pelvic ectasia 5, 2, 6.
- Mercaptoacetyl-triglycine renography and Tc-99m diethylene triamine penta-acetic acid (DPTA) dynamic renal scanning may also be used to assess renal function and urinary tract abnormalities 6, 4.