Percutaneous nephrostogram in the newborn with bilateral renal cystic disease

Percutaneous antegrade pyelography should be considered in the few, select, critically ill newborns with bilateral renal cystic disease when the diagnosis is critical to management and difficult with the usual imaging procedures. Two extremely ill newborns with severe oliguria and cystic abnormalities in both kidneys by ultrasound underwent sonographic guidance for percutaneous antegrade nephrostograms in the first week of life. With injection of contrast medium, definitive diagnoses were made of a multicystic dysplastic kidney on one side and an obstructed hydronephrotic kidney on the other, thereby directing decompression of the obstructed kidney to preserve native renal function. This procedure can provide a definitive diagnosis in these rare but difficult cases.

Office urologic ultrasound in pediatric patients

We use office ultrasound to supplement the pediatric urologist's office examination and follow the European model (J. Cukier, personal communication). The study can better serve the child and the family in this setting. We have shown that office ultrasound is an excellent primary screening modality, being both practical and accurate. The portable ultrasound machines now available should permit widespread use of office ultrasonography. However, office studies are not intended to replace studies with the more sophisticated and costly ultrasound machines used in radiology departments, only to complement them. We believe the primary uses of in-office examination in children at present are evaluating for detrusor thickness, residual urine volume, bladder capacity, hydronephrosis, and hydroureter; postoperative follow-up of hydronephrosis; screening for sibling uropathology; screening for occult uropathology in cases of gross hematuria; and study of voiding dysfunction or urinary infection. Experience has taught us that the better we become in performing inoffice ultrasound examinations, the better we use ancillary radiologic tests.

[Diagnosis of perforation of the kidney pelvis using sonography]

In a case report the diagnostics of a perforation of the renal pelvis using ultrasound is presented. Spontaneous urinary extravasations of the renal pelvis may appear in a previously diseased urinary tract also without the diuretic effect of contrast media. The ultrasound examination show the perirenal fluid collections and the diagnosis of spontaneous perforation of the renal pelvis is stated together with the clinical course.

Intermittent hydronephrosis: a diagnostic challenge

Intermittent hydronephrosis is a difficult condition to diagnose because of the mild degree of dilatation encountered in imaging studies. The condition nevertheless is disabling and attempts to reach a precise diagnosis include diuretic excretory urography, ultrasonography and renal scans. The delayed double-peak pattern seen on 99mtechnetium-diethylenetriaminepentaacetic acid diuretic renography shows how the ureteropelvic junction can become self-obstructing with forced diuresis. All patients who exhibited this sign eventually had frank obstruction and most exhibited an extrinsic component to the obstruction. The recognition of the double-peak pattern may become a useful adjunct in the early diagnosis of intermittent hydronephrosis.

Hydronephrosis secondary to colonic intussusception

We report on a two-month-old infant with bowel obstruction found to be secondary to a colonic intussusception (proved and reduced by barium enema). The finding of renal insufficiency prompted ultrasonographic renal evaluation uncovering a unilateral hydronephrosis. After resolution of the intussusception and hydration, the infant's renal functions normalized. Follow-up ultrasound study and renal scan showed resolution of the hydronephrosis. We conclude that colonic intussusception can cause renal obstruction.

Kock pouch urinary diversion: follow-up by ultrasound

In the post-operative follow-up of 24 patients who received a continent Kock pouch for urinary diversion, several complications were encountered, including hydronephrosis, stone formation and valve dysfunction, resulting in reflux and/or urinary incontinence. After comparing findings on ultrasound with those obtained by Koch pouch cystography, intravenous urography, plain abdominal radiography, Kock pouch endoscopy and operation, we consider ultrasound to be an important technique in the follow-up, especially in non-symptomatic patients. All cases of hydronephrosis and pouch calculi were detected by ultrasound and no false positive findings were encountered in either group. A good correlation is demonstrated between nipple length, as measured by ultrasound, and valve dysfunction, clinically important only for the afferent nipple.

[Echography in renal colic]

To determine the role of sonography (US) in patients with renal colic, 40 patients were examined by means of US, plain abdominal film (PF), and intravenous pyelography (ivp). US sensitivity was 92.3% in diagnosing hydronephrosis and 75% in detecting calculi. Small calculi were correctly identified, irrespective of their chemical composition. It must be stressed how US, as compared to ivp, proved unsatisfactory in such cases as difficult visualization of the middle portion of the ureter, unsuccessful identification of acute obstructions without hydronephrosis (although the patient's hydratation may be useful in this respect), poor functional information (although there was a correlation between renal hyper-echogenicity and obstructive nephrogram). US is safe and easy to perform, and is suggested for the initial evaluation of patients with renal colic, together with PF, and as an alternative to ivp. Moreover, US is the ideal technique in the follow-up of these patients. Therefore, ivp should be performed in case of differing clinical and sonographic findings, when the calculus is not ejected within the expected time, and when surgery or lithotripsy are foreseen.

[Does sonographic kidney morphology and morphometry provide evidence of pediatric kidney function?]

Compared with conventional X-ray investigation, ultrasound examination has a variety of advantages in the evaluation of urinary tract disorders in infancy and childhood. It does not involve exposure to contrast medium and radiation; low costs, minimal stress to the young patients, high diagnostic accuracy and easy reproducibility are further benefits. Postoperative follow-up of obstructive disorders can be easily performed and the results quantified by means of ultrasound. Morphometric data correlate well with renal function. As urologists become more familiar with ultrasonic morphologic and morphometric data, X-ray examinations in childhood will be confined to a few specific indications.

Prenatal diagnosis and management of bilateral hydronephrosis

This report reviews the management of the fetus with congenital hydronephrosis (CH), a challenging diagnostic and therapeutic problem. Experimental models of obstructive uropathy have produced histologic changes similar to those seen in kidneys of human neonates with congenital hydronephrosis. Relief of obstruction in utero in these models has been shown to prevent some of the dysplastic changes caused by obstruction. These studies have formed the theoretical basis for in utero decompression to restore amniotic fluid dynamics to prevent death from pulmonary hypoplasia, and reverse or arrest dysplastic morphogenesis. The development of prognostic criteria has greatly aided in selection of appropriate fetuses for intervention. These criteria include: (1) Na less than 100 mEq/l; (2) Cl less than 90 mEq/l; (3) osmolarity less than 210 mosmol; (4) sonographic appearance of the fetal kidneys; (5) amniotic fluid status; (6) urine output at fetal bladder catheterization. All fetuses should have ultrasonography to exclude other anomalies, and karyotype analysis to exclude chromosomal abnormality. If amniotic fluid volume is normal, the pregnancy is followed with serial ultrasound examinations. If oligohydramnios develops, a prognostic evaluation is performed, including fetal bladder catheterization. If the fetus has poor residual renal function, on the basis of prognostic criteria, appropriate counseling may be given. If the fetus has good residual renal function, depending on lung maturity, it can be delivered early for corrective surgery. If diagnosed prior to lung maturity in utero, decompression by either vesicoamniotic shunting or open fetal surgery may be attempted in the highly selected case.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of ureteropelvic junction obstruction in neonate

Fetal hydronephrosis demonstrated by maternal ultrasonography should lead to early investigation during the neonatal period. Postnatal confirmation of the diagnosis of ureteropelvic junction obstruction usually can be established by combining the radiologic modalities of ultrasound, diuretic isotope renal scan, and voiding cystourethrography. Rarely should intravenous urography, antegrade pyelography, or cystoscopy and retrograde pyelography be necessary. Findings of high-grade obstruction and/or significantly diminished function on the affected side(s) should prompt early neonatal reconstruction. Pyeloplasty was performed within the first month of life in 17 infants (20 kidneys) diagnosed as having significant ureteropelvic junction obstruction. Early reconstruction in the neonatal period can be performed successfully with minimal complications and a relatively brief period of hospitalization. This may ultimately achieve maximal preservation of renal function.

[Ureteral obstruction secondary to aortofemoral bypass]

Hydroureteronephrosis is reported as a frequent late complication of aorto-femoral bypass grafts in patients with aorto-iliac obstruction. To define the actual incidence of this potentially critical complication, renal ultrasonography (US) was performed on 79 asymptomatic patients who had previously undergone aortic reconstruction, after a mean interval of 71.6 months. Unilateral hydronephrosis was found in 6 cases (7.6%). Dilatation was mild or moderate (grade I or II) in 4 cases, and severe (grade III) in 2. Ivp was performed in this selected group: hydronephrosis was mild in 3 patients with ureteral stenosis where the iliac limb of the graft crossed the ureter. In 2 cases nonfunctioning kidneys were demonstrated corresponding to severe sonographic hydronephrosis. These 2 patients underwent anterograde and retrograde pyelography, that showed the site and extent of the obstruction. One patient was a false positive because of obstruction of pyelo-ureteral junction. Even though X-rays showed high sensitivity and specificity in detecting this complication of aorto-femoral reconstruction, US is noninvasive and less expensive and does not require contrast medium. A routine pre- and post-operative ultrasound study is suggested in patients undergoing by-pass surgery to early recognise ureteral obstruction and to avoid irreversible renal damage.

Renal dysplasia: sonographic findings

In 38 pediatric patients (predominantly neonates) with a proved pathologic diagnosis of renal dysplasia, a variety of sonographic appearances were seen. When the obstruction was at the level of the ureteropelvic junction (12 patients, 12 kidneys), the typical appearance was of a large kidney containing multiple large or moderate-sized cysts. When the obstruction was at the level of the distal ureter (14 patients, 14 kidneys), a smaller kidney containing a few cysts of variable sizes was usually seen. When the obstruction was at the level of the urethra (eight patients, 13 kidneys), the kidney was typically small with few or no cysts. In four patients (seven kidneys) in whom no cause of the obstruction was evident, the kidneys were small and echogenic. There was one case of segmental dysplasia.

Caution in antenatal intervention

We assessed 18 fetuses who harbored a urinary tract malformation that was diagnosed by antenatal sonography. The antenatal diagnosis corresponded to the postnatal diagnosis in 66 per cent of the cases. We review the course of 6 fetuses who had catheters placed percutaneously to drain dilated urinary tracts that were believed to be caused by posterior urethral valves (5) or an obstructed megaureter (1). Only 2 of these fetuses exhibited valves postnatally. No fetus had any recognized benefit from the antenatal intervention. We found that sonography may not readily differentiate fetuses with hydronephrosis with obstruction from those without obstruction. From this experience we conclude that intervention in pregnancies suspected of harboring a fetus with a malformed urinary tract should be done cautiously. Antenatal sonography is useful to identify the fetus with a dilated urinary tract. This identification permits perinatal specialists to be alerted so that preparations for reconstructive surgery in such cases can be made early postpartum.

Evaluation of azotemic patients: diagnostic yield of initial US examination

To determine whether renal ultrasound (US) is necessary in all patients with azotemia, the authors retrospectively evaluated renal US examinations in 394 azotemic patients. The patients included 119 patients considered clinically to be at high risk for postrenal urinary obstruction and 275 patients considered to be at low risk. In the high-risk population, 35 patients were found to have hydronephrosis (29%). In the low-risk population, three patients were found to have hydronephrosis (1%). In two of these patients surgical intervention resulted in reversal of the azotemia. The authors recommend that renal US be performed in all high-risk patients and in low-risk patients only if temporization and standard medical treatment do not resolve the azotemia.

Hydronephrosis during pregnancy: four cases of hydronephrosis causing symptoms during pregnancy

Hydronephrosis during pregnancy is a physiological phenomenon in the majority of pregnant women after the 20th week of pregnancy; normally it gives rise to no symptoms. Four cases of hydronephrosis causing symptoms during pregnancy are described, where ureteral colic has been the reason for hospitalization. An evaluation is given of the indications and the methods of treatment, including the employment of an indwelling ureteral catheter.

Unsuspected urological anomalies in asymptomatic cryptorchid boys

In a period of 6 years 144 asymptomatic boys with cryptorchidism, of mean age 7 +/- SD 3.5 years, underwent orchiopexy. None of these boys referred to a history of a known urological anomaly, urinary tract infection, haematuria, palpable mass in the renal region, bladder extrophy, epispadias, hypospadias or anorectal malformation. On the third day after orchiopexy and intravenous pyelography was done in every boy following testicular protection against irradiation. Ultrasonic investigation was not available at that time. There were minor urological abnormalities in 36 (25%) boys and major ones in 8 (5.5%) boys. A major anomaly is defined as one resulting in significant loss of renal substance (one case of single kidney and three cases of unilateral renal hypoplasia), or requiring surgical correction for conservation of the renal substance (one case of ureterocele, two cases of pelviureteric stenosis and one case of vesicoureteric stenosis with ipsilateral hydronephrosis). The unsuspected major urological abnormalities are usually ipsilateral to the more undescended testis. They may be associated with a hernia and are more frequent in bilateral cryptorchidism. In conclusion we encourage the routine use of IVP, or ultrasonic investigation or dynamic renal scanning (99mTc-DTPA), if it is possible, in all patients undergoing orchiopexy for the detection of an unsuspected major renal anomaly.

Multicystic dysplastic kidneys and diagnostic confusion on renal scan

The combination of ultrasound and renal scan usually provides a reliable means of differentiating congenital ureteropelvic junction obstruction with hydronephrosis from multicystic dysplasia in the newborn with an abdominal mass. Rarely, a multicystic kidney will show definite function on a renal scan. We describe 2 newborns who were thought to have hydronephrosis based on a renal scan but who had typical multicystic dysplastic kidneys at operation.