Unilateral urinary flow impairment at the pelviureteral junction: outcome of renal function with respect to therapeutic strategy

Laparoscopic pyeloplasty as an alternative to nephrectomy in adults with poorly functioning kidneys due to ureteropelvic junction obstruction

OBJECTIVES

To evaluate outcomes of laparoscopic pyeloplasty (LP) in adults with poorly functioning kidney due to ureteropelvic junction obstruction (UPJO).

METHODS

A retrospective comparative analysis was performed between adult patients who underwent LP due to UPJO with differential renal function (DRF) ≤ 15% and DRF > 15%. LP success rate and complications were assessed. LP success was defined as symptoms improvement and DRF improvement or stabilization. DRF and estimated glomerular filtration rate (eGFR) were analyzed before and 12 months after surgery to evaluate renal function recovery. DRF was estimated using Tc-99 m DMSA renal scintigraphy.

RESULTS

Among 121 LP performed in the study period at our institution, 15 and 42 were included in the DRF ≤ 15% and DRF > 15% groups, respectively. At a median follow-up of 17.8 months, all patients with DRF ≤ 15% reported symptoms improvement. LP success rate was 86.7% and 90.5% (p = 0.65) for patients with DRF ≤ 15% and DRF > 15%, respectively. There were no complications in the DRF ≤ 15% group, while there were three complications recorded in the DRF > 15% group (Clavien 2 and 3b). In the DRF ≤ 15% group, mean pre-operative and post-operative DRF was 9.5% ± 3.6 and 10.5% ± 7.8 (p = 0.49), respectively. Median pre-operative and post-operative eGFR was 68.5 ml/min and 79.8 ml/min (p = 0.93), respectively. Two patients had DRF improvement after LP.

CONCLUSIONS

LP in adult patients with UPJO and poor function kidneys is an effective and safe procedure. DRF recovery is seen in a minority of the patients; however, LP is an alternative to nephrectomy.

Is it Always Necessary to Treat an Asymptomatic Hydronephrosis Due to Ureteropelvic Junction Obstruction?

The postnatal treatment of asymptomatic unilateral hydronephrosis due to ureteropelvic junction obstruction remains controversial, and the timing of and indications for surgical intervention are continuously debated. There is no consensus on the best follow-up during expectant management. The various modalities and parameters have been discussed along with their pros and cons and an attempt has been made to clear up the controversies.

Pyeloplasty in children: is there a difference in patients with or without crossing lower pole vessel?

INTRODUCTION

Most of the children with hydronephrosis do not require any surgical intervention. However, in individual cases, irreversible loss of renal function can develop. Predictive criteria have been proven ineffective so far in determining in which children obstruction will lead to renal damage. The aim of our retrospective study was to determine the role of a crossing lower pole vessel (CV) in children undergoing pyeloplasty.

MATERIALS AND METHODS

Between 1996 and 2003, 137 patients (age between 6 weeks and 16 years) with unilateral ureteropelvic junction obstruction and no associated urological pathologies underwent Anderson-Hynes dismembered pyeloplasty. A total of 112 patients were evaluated with complete data. One of the following criteria was considered to be indication for surgery in children with grade 4 hydronephrosis: differential renal function (DRF) <40%; clinical symptoms such as pyolenephritis and flank pain; during follow-up renographies, a reduction of DRF >10% and washout patterns II or III b according to O'Reilly. We looked at the age during surgery and the kind of presentation. DRF was measured using diuretic renography preoperatively and 1 year postoperatively. A postoperative change in DRF of group A (children without CV, n = 84) was compared to that in group B (children with CV, n = 28).

RESULTS

Median age at the time of surgery was 5 months in group A compared to 23 months in group B. Only in 21.4% of the children with CV compared to 60.7% without CV hydronephrosis was diagnosed by ultrasound examination antenatally. We found a preoperative DRF of 42.4% +/- 11.2 SD in group A, and of 38.9% +/- 11.7 SD in group B. The percentage of postoperative improvement was 3.3% in group A and 15.4% in group B.

CONCLUSIONS

Children with ureteropelvic junction obstruction and CV received a delayed surgical treatment and showed a greater reduction in differential renal function preoperatively, in contrast to patients without CV. Our data show that CV is a risk factor for deterioration of renal function in children with hydronephrosis and we advocate for an early pyeloplasty in these children, especially if they have a high-grade dilatation and equivocal washout patterns in diuretic renographies. Further prospective studies are necessary in order to understand the natural history of CV and to reveal the importance of the crossing lower pole vessel as a structural anomaly lacking maturation.

Prenatally diagnosed urinary tract abnormalities: long-term outcome

The long-term outcomes of prenatally detected uropathies are poorly documented. Limited data on fetal intervention show a possible reduction in early mortality from pulmonary hypoplasia, but no beneficial effect on long-term prognosis for renal function. Prenatally detected vesicoureteric reflux (VUR) is characterised by males with high-grade primary reflux, who are at long-term risk of renal impairment. Prenatal diagnosis and surgical intervention have contributed to a reduction in long-term morbidity in children with pelviureteric junction (PUJ) obstruction. By the same token, many children have almost certainly undergone unnecessary early pyeloplasty for an obstruction that would have resolved spontaneously. Multicystic dysplastic kidney (MCDK) carries a low (1%) risk of hypertension in childhood. The limited evidence on the long-term outcome of mild dilatation (pelvicaliectasis) indicates this is a largely innocent finding, which carries no increased risk of morbidity.

[Severe primary congenital unilateral hydronephrosis. A review of 98 cases]

INTRODUCTION

Currently, consensus is lacking on the indications for surgery in primary congenital unilateral hydronephrosis.

OBJECTIVES

To analyze the clinical characteristics, treatment and outcome of severe asymptomatic primary congenital unilateral hydronephrosis (grades 3 and 4).

PATIENTS AND METHODS

We performed a retrospective study of 98 neonates with severe primary congenital unilateral hydronephrosis. Diagnostic techniques consisted of ultrasound, renogram, and DMSA scan.

RESULTS

The mean age at diagnosis was 24 days. The mean length of follow-up was 4 years. Forty-eight percent of cases were grade 3 and the remaining cases were grade 4. Fifty-six percent of the patients received conservative treatment. Forty-four percent underwent surgery. Surgical indications consisted of prolonged T1/2, reduced differential renal function and/or very severe hydronephrosis. The mean age at surgery was 5.5 months. In 94 % of the patients who received conservative treatment, hydronephrosis resolved spontaneously. In this group, renal parenchyma and renal function were normal in all patients except two. In 97 % of the patients who received surgical treatment, hydronephrosis was corrected or improved after pyeloplasty. At diagnosis, 19 kidneys had reduced function. In the postsurgical renogram, although T1/2 had markedly improved, 8 kidneys showed reduced function. DMSA performed in 63 patients belonging to both groups, outside the active phase of hydronephrosis, revealed 8 atrophic kidneys, 4 with moderately reduced renal size and function and 4 with scarring and normal renal size and function. During the study period, overall function was maintained in all patients and none developed hypertension.

CONCLUSIONS

Severe congenital unilateral hydronephrosis resolves spontaneously in most patients. Consequently, clinicians increasingly adopt a conservative approach. The available diagnostic techniques cannot identify patients who will benefit from pyeloplasty. In general, accepted surgical indications are an increase in hydronephrosis and/or worsening of renal function. In our series, 15 % of the patients with hydronephrosis had an irreversible lesion of variable severity, which in some patients seemed to have developed during embryogenesis. Kidneys at risk of presenting a lesion were those that had grade 4 hydronephrosis.

PRENATALLY DIAGNOSED UNILATERAL RENAL PELVIC DILATATION: A DYNAMIC CONDITION ON ULTRASOUND AND DIURETIC RENOGRAPHY

PURPOSE

Imaging characteristics obtained from serial scintigraphic and ultrasonographic studies in children with the prenatal diagnosis of unilateral pelvic dilatation are presented.

MATERIALS AND METHODS

Serial ultrasonographic and scintigraphic findings in 101 children with unilateral pelvic dilatation collected during followup were reviewed. Changes in hydronephrotic kidney in terms of renal pelvis diameter, kidney size, differential renal function and drainage were noted. A total of 42 children underwent surgery at a mean age of 15.6 months (range 3.1 to 69.2, median 8.2), while 59 were treated nonsurgically.

RESULTS

Mean age at presentation was 5.6 months (range 0.8 to 36.4, median 3.5). Mean followup was 35.5 months (range 6.4 to 78.4, median 29.6). Differential renal function remained stable (46.4% vs 47.3%) but improved drainage (68.4% vs 81.2%) and decreased renal pelvis size (22.2 vs 18.3 mm) was noted in the 2 groups. With age drainage function improved, especially between the younger than 12-month and 12-month or older groups. The mean affected-to-unaffected kidney length ratio at presentation was significantly greater than the ratio at the final followup (paired t test p <0.05).

CONCLUSIONS

In this retrospective review drainage function was prolonged in infants. During followup drainage, dilatation and relative renal size improved in the surgery and nonsurgery groups. There was no change in renal function in either groups during followup. These data support the benign nature of prenatal unilateral hydronephrosis.