Data regarding spontaneous resolution of mild hydronephrosis consist of different etiologies, and hence, it is heterogeneous. The aim of this study is to evaluate spontaneous resolution rates and the time to complete resolution of antenatally detected isolated hydronephrosis in patients with renal pelvis antero-posterior diameter (RPAPD) ≤ 20 mm. Retrospective chart review of patients who were admitted to our pediatric nephrology clinic for the evaluation of antenatal hydronephrosis between 2011 and 2017 was conducted. Patients that had hydronephrosis with RPAPD ≤ 20 mm, < SFU (Society for Fetal Urology) grade IV on initial postnatal evaluation, and ≥ 3 months of follow-up with at least two renal ultrasounds (US) were included. Complete resolution of hydronephrosis was regarded as SFU grade 0 with a RPAPD of < 7 mm. Patients with ureteric and lower urinary tract abnormalities were excluded. There were a total of 276 patients who met the inclusion criteria. Median follow-up was 16 months (range 3–96 months). Hydronephrosis completely resolved in 198 patients (71.7%). Surgery was not required in any of the patients; however, nine patients (3.3%) showed progression to higher grades of hydronephrosis or increase in AP diameter. Median time to complete resolution of hydronephrosis was 6 months (range 2–35 months) in our study. Those with AP diameter < 10 mm became normal in median of 5 months, while it took median 11 months for patients with AP diameter 10–20 mm to become normalized (p < 0.001).
Conclusion: Isolated antenatal hydronephrosis with RPAPD ≤ 20 mm would spontaneously resolve in 71.7% of the cases. Resolution may be expected to happen in 3 years, while the majority will take place in the first year of life.
What is Known:
• Antenatal hydronephrosis comprises an important amount of clinical visits.
• Spontaneous resolution rates differ for various etiologies.
What is New:
• Isolated antenatal hydronephrosis with RPAPD ≤ 20 mm completely resolves within 3 years in approximately 72% of the cases.
• Resolution can be observed within the first year of life in most of the cases.
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Alconcher LF, Tombesi MM (2012) Natural history of bilateral mild isolated antenatal hydronephrosis conservatively managed. Pediatr Nephrol 27(7):1119–1123. https://doi.org/10.1007/s00467-012-2113-0
Arora S, Yadav P, Kumar M, Singh SK, Sureka SK, Mittal V, Ansari MS (2015) Predictors for the need of surgery in antenatally detected hydronephrosis due to UPJ obstruction—a prospective multivariate analysis. J Pediatr Urol 11(5):248 e241–248 e245. https://doi.org/10.1016/j.jpurol.2015.02.008
Braga LH, McGrath M, Farrokhyar F, Jegatheeswaran K, Lorenzo AJ (2017) Associations of initial Society for Fetal Urology Grades and Urinary Tract Dilatation Risk Groups with clinical outcomes in patients with isolated prenatal hydronephrosis. J Urol 197(3 Pt 2):831–837. https://doi.org/10.1016/j.juro.2016.08.099
Braga LH, McGrath M, Farrokhyar F, Jegatheeswaran K, Lorenzo AJ (2018) Society for Fetal Urology Classification vs urinary tract dilation grading system for prognostication in prenatal hydronephrosis: a time to resolution analysis. J Urol 199(6):1615–1621. https://doi.org/10.1016/j.juro.2017.11.077
Chalmers DJ, Meyers ML, Brodie KE, Palmer C, Campbell JB (2016) Inter-rater reliability of the APD, SFU and UTD grading systems in fetal sonography and MRI. J Pediatr Urol 12(5):305 e301–305 e305. https://doi.org/10.1016/j.jpurol.2016.06.012
Coelho GM, Bouzada MC, Pereira AK, Figueiredo BF, Leite MR, Oliveira DS, Oliveira EA (2007) Outcome of isolated antenatal hydronephrosis: a prospective cohort study. Pediatr Nephrol 22(10):1727–1734. https://doi.org/10.1007/s00467-007-0539-6
Dias CS, Silva JM, Pereira AK, Marino VS, Silva LA, Coelho AM, Costa FP, Quirino IG, Simoes ESAC, Oliveira EA (2013) Diagnostic accuracy of renal pelvic dilatation for detecting surgically managed ureteropelvic junction obstruction. J Urol 190(2):661–666. https://doi.org/10.1016/j.juro.2013.02.014
Fernbach SK, Maizels M, Conway JJ (1993) Ultrasound grading of hydronephrosis: introduction to the system used by the Society for Fetal Urology. Pediatr Radiol 23(6):478–480
Liu DB, Armstrong WR 3rd, Maizels M (2014) Hydronephrosis: prenatal and postnatal evaluation and management. Clin Perinatol 41(3):661–678. https://doi.org/10.1016/j.clp.2014.05.013
Longpre M, Nguan A, Macneily AE, Afshar K (2012) Prediction of the outcome of antenatally diagnosed hydronephrosis: a multivariable analysis. J Pediatr Urol 8(2):135–139. https://doi.org/10.1016/j.jpurol.2011.05.013
Nguyen HT, Herndon CD, Cooper C, Gatti J, Kirsch A, Kokorowski P, Lee R, Perez-Brayfield M, Metcalfe P, Yerkes E, Cendron M, Campbell JB (2010) The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis. J Pediatr Urol 6(3):212–231. https://doi.org/10.1016/j.jpurol.2010.02.205
Nguyen HT, Benson CB, Bromley B, Campbell JB, Chow J, Coleman B, Cooper C, Crino J, Darge K, Herndon CD, Odibo AO, Somers MJ, Stein DR (2014) Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system). J Pediatr Urol 10(6):982–998. https://doi.org/10.1016/j.jpurol.2014.10.002
Passerotti CC, Kalish LA, Chow J, Passerotti AM, Recabal P, Cendron M, Lee RS, Lopez AB, Retik AB, Nguyen HT (2011) The predictive value of the first postnatal ultrasound in children with antenatal hydronephrosis. J Pediatr Urol 7(2):128–136. https://doi.org/10.1016/j.jpurol.2010.09.007
Scalabre A, Demede D, Gaillard S, Pracros JP, Mouriquand P, Mure PY (2017) Prognostic value of ultrasound grading systems in prenatally diagnosed unilateral urinary tract dilatation. J Urol 197(4):1144–1149. https://doi.org/10.1016/j.juro.2016.11.103
Tombesi MM, Alconcher LF (2012) Short-term outcome of mild isolated antenatal hydronephrosis conservatively managed. J Pediatr Urol 8(2):129–133. https://doi.org/10.1016/j.jpurol.2011.06.009
Yamacake KG, Nguyen HT (2013) Current management of antenatal hydronephrosis. Pediatr Nephrol 28(2):237–243. https://doi.org/10.1007/s00467-012-2240-7
Zee RS, Herndon CDA, Cooper CS, Kim C, McKenna PH, Khoury A, Herbst KW (2017) Time to resolution: a prospective evaluation from the Society for Fetal Urology hydronephrosis registry. J Pediatr Urol 13(3):316 e311–316 e315. https://doi.org/10.1016/j.jpurol.2016.12.012
We would like to thank Amanda F. Saltzman, MD (Children’s Hospital Colorado), for kindly reviewing the manuscript.
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Communicated by Mario Bianchetti
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Elmaci, A.M., Dönmez, M.İ. Time to resolution of isolated antenatal hydronephrosis with anteroposterior diameter ≤ 20 mm. Eur J Pediatr 178, 823–828 (2019). https://doi.org/10.1007/s00431-019-03359-y
- Antenatal hydronephrosis
- Spontaneous resolution