DOI: http://dx.doi.org/10.18203/2349-3291.ijcp20162371

Role of fetal renal pelvic dilatation - as a predictor of neonatal urological outcome

Abhishek MV, Bhavana G.

Abstract


Background: Mild pelvic dilatation is relatively frequent in the normal fetus but once it is detected, adequate follow-up is required. An abnormal finding, can affect parental attitude towards the pregnancy and their unborn baby. Therefore, it is necessary to have specific ultrasound criteria that differentiate transient dilatation from pathological abnormality to offer an accurate counseling to the parents. To evaluate the need for postnatal treatment- surveillance and or surgery in relation to grade of renal pelvic dilatation found on third trimester ultrasound and to identify a cut-off value of APD which discriminates transient pelvic dilatation from pathological abnormality.

Methods: A Hospital based prospective study was conducted at Fernandez hospital, Fetal Medicine Unit (FMU), Hyderabad by reviewing the hospital records from January 2010 to January 2015 among 310 Antenatal cases with isolated fetal renal pelvic diameter (APD) > 7 mm in third trimester on ultrasound were included and post natal follow up was done for 1 year duration.

Results: Post natal follow up identified that out of 162 mildly dilated renal pelvic units (APD 7-9 mm) 98 cases (60.4%) resolved and none required surgery. Out of 117 moderate hydronephrosis (APD 9-15 mm) 22 cases resolved (18.8%), 11 cases (9%) required surgery and out of 18 cases with severe hydronephrosis (APD of > 15mm) none of them resolved and 6 cases needed surgery. The cases which required surgery had either moderate or severe hydronephrosis with mean renal pelvic diameter of 11.3 mm. Similarly on the basis of receiver operating characteristic curves, the renal threshold that best predicted surgery in postnatal period was anteroposterior diameter of > 11 mm in third trimester, yielding sensitivity - 74.07%, specificity -93.97%, positive likelihood ratio - 12.27, not clinically significant.

Conclusions: The need for postnatal treatment increased with the grade of antenatal RPD. Neonates with antenatal mild dilatation (renal pelvis diameter < 9 mm) were discharged early from follow-up whereas those with RPD > 11 mm required surgery.


Keywords


Urinary tract, Fetal anomalies, Hydronephrosis, Gestation

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References


Dudley JA, Haworth JM, McGraw ME et al. Clinical relevance and implications of antenatal hydronephrosis. Arch Dis Childhood 1997;76:F31-F34.

Sinha A, Bagga A, Krishna A. Revised guidelines on management of antenatal hydronephrosis. Indian Pediatr. 2013;50:215-31.

Livera LN, Brookfield DSK, Egginton JA. Antenatal ultrasonography to detect fetal renal abnormalities: A prospective screening programme. Br Med J. 1989;298:1421-3.

Sairam S, Al-Habib A, Sasson S. Natural history of fetal hydronephrosis diagnosed on mid-trimester ultrasound. Ultrasound Obstet Gynecol. 2001;17(3):191-6.

deKort EH, Bambang Oetomo, Zegers SH. The long-term outcome of antenatal hydronephrosis up to 15 millimeters justifies a noninvasive postnatal follow-up. Acta Pediatr. 2008;97(6):708-13.

Maayan-Metzger A, Lotan D, Jacobson JM. The yield of early postnatal ultrasound scans in neonates with documented antenatal hydronephrosis. Am J Perinatol. 2011;28(8):613-8.

Wollenberg A, Neuhaus TJ, Willi UV. Outcome of fetal renal pelvic dilatation diagnosed during the third trimester. Ultrasound Obstet Gynecol. 2005;25(5):483-8.

Feldman DM, DeCambre M, Kong E. Evaluation and follow-up of fetal hydronephrosis. J Ultrasound Med. 2001;20(10):1065-9.

Longpre M, Nguan A, Macneily AE. Prediction of the outcome of antenatally diagnosed hydronephrosis: a multivariable analysis. J Pediatr Urol. 2012;8(2):135-9.

Babu R, Sai V. Postnatal outcome of fetal hydronephrosis: implications for prenatal counselling. Indian J Urol. 2010;26(1):60-2.

Oktar T, Acar O, Atar A. How does the presence of antenatally detected caliectasis predict the risk of postnatal surgical intervention? Urology. 2012;80(1):203-6.

Signorelli M, Cerri V, Taddei F. Prenatal diagnosis and management of mild fetal pyelectasis: implications for neonatal outcome and follow-up. Eur J Obstet Gynecol Reprod Biol. 2005;118(2):154-9.

Ouzounian JG, Castro MA, Fresquez M. Prognostic significance of antenatally detected fetal pyelectasis. Ultrasound Obstet Gynecol. 1996;7(6):424-8.

Kim HJ, Jung HJ, Lee HY. Diagnostic value of anteroposterior diameter of fetal renal pelvis during second and third trimesters in predicting postnatal surgery among Korean population: useful information for antenatal counseling. Urology. 2012;79(5):1132-7.

Coplen DE, Austin PF, Yan Y. The magnitude of fetal renal pelvic dilatation can identify obstructive postnatal hydronephrosis, and direct postnatal evaluation and management. J Urol. 2006;176(2):724-7.