Mercaptoacetyltriglycine (MAG-3) renogram is one of the gold standard diagnostic tools of ureteropelvic junction obstruction (UPJO); however, there is no widely agreed indications of pyeloplasty based on MAG-3 findings. In this study, we introduce a renogram scoring system that can help improve the prognostic value of MAG-3 renogram and in the decision making of pyeloplasty.
Patients and methods
We retrospectively reviewed consecutive pyeloplasties for antenatal hydronephrosis from 2010 to 2020. A control group was included of non-operatively managed SFU grade 3 and 4. The initial renal ultrasound and preoperative MAG-3 Lasix renogram were reviewed for differential renal function (DRF), type of renogram curve and tracer washout half-time (T1/2). A ROC curve was used to evaluate the cut-off points that can be associated with obstruction. A multivariate linear regression model was used to assess the best renogram parameter that can predict surgical intervention.
We included 188 patients with 209 renal units. The median age for pyeloplasty was 5.4 months. The mercaptoacetyltriglycine-Suspected Obstruction Scoring System (MAG-SOS) was associated with pyeloplasty (AUC = 0.97, P < 0.001) (Figure A). A score of 5 is 100% specific for obstruction. 78% of units required surgical intervention had a MAG-SOS score of≥5 while all units of the control group had a range of score 0–4. Using the multivariate analysis, the MAG-SOS system showed to the only independent predictor for pyeloplasty (HR = 0.03, p < 0.001).
This study has some limitations. Firstly, the retrospective nature of the cohort; however, all patients were reviewed by one investigator who was blinded to the line of management. This is a single institutional study; therefor, this MAG-SOS should be evaluated by other centers to ensure its efficiency. Lastly, the pyeloplasty decision was taken by 3 different urologists; nevertheless, all of them adopt the same indications which are similar to those of the Society for Pediatric Urology and the Canadian Urological Association guidelines.
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- The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis.J Pediatr Urol. 2010; 6: 212-231
- Postnatal management of newborn with antenatal detected urinary tract abnormalities.J Matern Fetal Neonatal Med. 2011; 24: 107-110
- Is the renal pyramidal thickness a good predictor for pyeloplasty in postnatal hydronephrosis?.J Pediatr Urol. 2018; 14: 277 e1-e6
- Prediction of clinical Outcomes in prenatal hydronephrosis: Importance of gravity assisted drainage.J Urol. 2017; 197: 838-844
- Diuretic renography with the addition of quantitative gravity-assisted drainage in infants and children.J Nucl Med. 2000; 41: 1030-1036
- Validation of modified diuretic drainage times criteria in congenital hydronephrosis.J Pediatr Urol. 2021; 17: 832 e1-e8
- Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system).J Pediatr Urol. 2014; 10: 982-998
- Ultrasound grading of hydronephrosis: introduction to the system used by the Society for Fetal Urology.Pediatr Radiol. 1993; 23: 478-480
- The SNMMI and EANM procedural guidelines for diuresis renography in infants and children.J Nucl Med. 2018; 59: 1636-1640
- Diuresis renography in equivocal urinary tract obstruction.Br J Urol. 1978; 50: 76-80
- Intermittent hydronephrosis: a diagnostic challenge.J Urol. 1988; 140: 1222-1226
- Variability of diuresis renography interpretation due to method of post-diuretic renal pelvic clearance half-time determination.J Urol. 2000; 164: 467-471
- Evaluation and management of upper urinary tract obstruction in infancy and childhood.Urol Clin North Am. 1985; 12: 133-141
- Observation of infants with SFU grades 3-4 hydronephrosis: worsening drainage with serial diuresis renography indicates surgical intervention and helps prevent loss of renal function.J Pediatr Urol. 2011; 7: 266-271
- Antenatally detected pelvi-ureteric junction obstruction: concerns about conservative management.BJU Int. 1999; 84: 335-338
- The long-term followup of newborns with severe unilateral hydronephrosis initially treated nonoperatively.J Urol. 2000; 164: 1101-1105
- Validation of renal output efficiency as an objective quantitative parameter in the evaluation of upper urinary tract obstruction.J Nucl Med. 1993; 34: 845-848
- The "well tempered" diuretic renogram: a standard method to examine the asymptomatic neonate with hydronephrosis or hydroureteronephrosis. A report from combined meetings of the Society for Fetal Urology and members of the Pediatric Nuclear Medicine Council--The Society of Nuclear Medicine.J Nucl Med. 1992; 33: 2047-2051
- Procedure guideline for diuretic renography in children 3.0.J Nucl Med Technol. 2008; 36: 162-168
- Guidelines for standard and diuretic renogram in children.Eur J Nucl Med Mol Imaging. 2011; 38: 1175-1188
- Comparison of the EANM and SNM guidelines on diuretic renography in children.Nucl Med Commun. 2015; 36: 486-488
- The postnatal management of hydronephrosis diagnosed by prenatal ultrasound.J Urol. 1990; 144 (discussion 93-4): 584-587
- The nonoperative management of unilateral neonatal hydronephrosis: natural history of poorly functioning kidneys.J Urol. 1994; 152: 593-595
- Assessment of pediatric hydronephrosis using output efficiency.J Nucl Med. 1997; 38: 1483-1486
- Pyeloplasty vs. nephrectomy for ureteropelvic junction obstruction in poorly functioning kidneys (differential renal function <20%): a multicentric study.J Pediatr Urol. 2019; 15: 553 e1-e8
- Outcome of poorly functioning kidneys secondary to PUJO preserved by pyeloplast.J Pediatr Surg. 2017; 52: 578-581
- Canadian Urological Association/Pediatric Urologists of Canada guideline on the investigation and management of antenatally detected hydronephrosis.Can Urol Assoc J. 2018; 12: 85-92
Published online: March 02, 2023
Accepted: February 25, 2023
Received in revised form: February 22, 2023
Received: November 1, 2022
Publication stageIn Press Journal Pre-Proof
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