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.

Acute renal failure due to bilateral ureteral obstruction by the pregnant uterus

We report a case of post-renal insufficiency in the 26th week of a normal pregnancy; the cause being bilateral ureteral obstruction by the pregnant uterus. By placing double-J-catheters in both ureters the patient was able to continue pregnancy to term. The catheters were removed 1 week postpartum.

Preoperative symptomatology and diagnostic findings in relation to outcome of pyeloplasty in patients with primary hydronephrosis

Sixty-seven patients, aged 3-71 years, with primary hydronephrosis were operated at our department during a 5-year period. All patients had Anderson-Hynes pyeloplasty. The primary clinical result of surgery was excellent in 63 patients (94%). Of the patients with reduced renographic uptake fraction preoperatively, 38% had a significant gain 6 months after reconstruction, while only 1 patient had a reduction. There was no correlation between the outcome of reconstruction and preoperative history, degree of hydronephrosis on IVP, preoperative functional share on renography or the peroperative finding of aberrant vessels compressing the ureter. It was concluded that surgery should be undertaken on rather wide indications as reconstruction leads to stable or improved renal function regardless of preoperative symptoms or diagnostic findings.

Sensitivity of 131I-hippuran diuresis renography and pressure flow study (Whitaker test) in upper urinary tract obstruction

Diuresis renography and pressure flow studies were performed in 14 patients with unilateral hydronephrosis. Based upon the results of intravenous pyelography, typical symptomatology, and the outcome of surgical treatment, all patients were found to have upper urinary tract obstruction. It was therefore possible to calculate the sensitivity of the two tests. Obstruction was found at the pressure flow studies in 7 of 14 patients (50%), while an obstructive pattern was found at diuresis renography in 12 of 13 patients (92%). Due to a very low glomerular filtration rate, diuresis renography was equivocal in 1 case. Based upon these results, diuresis renography seems to be superior to pressure flow studies in cases with upper urinary tract obstruction.

[Clinical definition of asymptomatic abdominal masses]

Five patients with asymptomatic abdominal masses (abdominal leiomyosarcoma, giant hydronephrosis, renal cell carcinoma, squamous cell carcinoma of the lung metastatic to the adrenal gland, retroperitoneal non-Hodgkin's lymphoma) are reported. Non invasive investigations such as Echography and Computed Tomography, are very advantageous for the quick diagnosis of asymptomatic abdominal masses and for subsequent therapy.

Urinary obstruction in azotemic patients: detection by sonography

Renal sonography is frequently requested in patients with an elevated or rising creatinine, often with the instruction to "rule out obstruction." A prospective study of patients undergoing renal sonography for newly discovered azotemia (creatinine greater than 1.8 mg/dl) or worsening renal failure was undertaken to evaluate the clinical utility of the sonographic examination. Patients with known obstructive uropathy, renal calculi, renal mass, or hematuria were excluded. In 189 patients, 17 (9%) had hydronephrosis: 11 unilateral (one with a solitary kidney) and six bilateral. Obstructive causes were subsequently established in the solitary kidney and in four patients with bilateral dilatation. These five patients (2.6%) with clinically significant hydronephrosis were shown subsequently to have a clinical history that strongly suggested the presence of urinary tract obstruction. Our data suggest that, in patients without a clinical history that suggests obstruction (such as calculi, bladder outlet obstruction, or pelvic mass), the likelihood of finding bilateral hydronephrosis by sonography is small.

Normal and hydronephrotic kidney: evaluation of renal function with contrast-enhanced MR imaging

Four healthy volunteers and six patients with hydronephrosis underwent magnetic resonance (MR) imaging after the injection of gadolinium-diethylenetriaminepenta-aceticacid for the assessment of renal function. Coronal angulated 10-second images were obtained during suspended respiration (inspiratory apnea) and showed excellent anatomic detail. In healthy volunteers, the renal cortex showed an increase in signal intensity after Gd-DTPA injection, and the renal medulla showed a precipitous decrease in intensity approximately 1 minute after injection, followed by a gradual increase in intensity. The renal pelvis showed a gradual decrease in intensity after several minutes, with occasional signal-void areas in adjacent structures. In patients with hydronephrosis, the decrease in intensity in the medulla and pelvis was not observed; instead, an increase in intensity occurred. The physiologic function of glomerular filtration and in vitro results of serial dilutions of Gd-DTPA suggest that the decrease in intensity is due to T2 and susceptibility effects occurring at high concentrations of Gd-DTPA.

Renal abnormalities in paucity of interlobular bile ducts

Paucity of interlobular bile ducts is a common histologic characteristic in persistent conjugated hyperbilirubinemia of infancy. It occurs in two forms: the syndromatic and the nonsyndromatic types. The syndromatic form is also called arteriohepatic dysplasia. The nonsyndromatic type of paucity of interlobular bile ducts occurs less frequently and is usually associated with more severe disease and a less favorable prognosis. We present two unusual renal anomalies in association with paucity of interlobular bile ducts. In the first case, juvenile nephronophthisis was diagnosed in a 4-week-old infant with arteriohepatic dysplasia; the patient died from severe renal disease by 2 months of age. The second case presented with severe bilateral hydronephrosis and hydroureter secondary to posterior urethral valves associated with the nonsyndromatic form of paucity of interlobular bile ducts. He, however, improved after corrective surgery of the urethral valves. Other renal abnormalities previously reported in the literature in association with chronic liver disease are also reviewed.

Intervention for fetal obstructive uropathy: has it been effective?

The best management of fetal hydronephrosis is controversial. Despite the lack of experimental evidence that prenatal drainage of the obstructed urinary tract substantially improves ultimate renal function, various forms of percutaneous intervention on the fetal bladder and kidney have been used. To evaluate the efficacy of intervention for suspected fetal obstructive uropathy, all published reports of drainage of the fetal urinary tract up to December, 1985, were reviewed. In the 57 reported cases, the most common type of intervention was placement of a vesicoamniotic shunt (37%). Complications occurred in 25 cases (44%), including inadequate shunt drainage or migration (19%), onset of premature labour within 48 h (12%), urinary ascites (7%), and chorioamnionitis (5%). Of 28 fetuses with associated oligohydramnios, only 6 (21%) survived. 2 of these survivors had vesicoamniotic shunts, 2 single or multiple bladder aspirations, 1 an external renal drainage catheter, and 1 in-utero vesicostomy. Because of the high complication rate and lack of evidence of improved survival from in-utero drainage procedures, a prospective, randomised trial is needed to compare survival with and without vesicoamniotic shunt placement.

Neonatal renomegaly

A retrospective clinical review was done to study the value of ultrasound and renography in the investigation of 100 neonates with renomegaly. Abnormalities in 73 patients were detected antenatally with ultrasonography. Of the neonates 47 had lower urinary tract pathological conditions and ultrasound was more than 90 per cent accurate in identifying the accompanying ureteral dilatation. A total of 53 neonates had upper tract anomalies (ureteropelvic junction obstruction or cystic dysplasia). With ultrasonography the degree of pyelocaliectasis in patients with ureteropelvic junction obstruction was classified as mild (22 units), moderate (13) or severe (7). Initial treatment and followup were reviewed to study the clinical course of neonates with mild to moderate degrees of pyelocaliectasis followed nonoperatively, and to determine whether the diuretic renogram had a predictive role in identifying which kidneys were most likely to deteriorate.

[Serum beta 2-microglobulin in spinal cord injury patients--its efficacy as a screening test of renal function]

We evaluated the reliability of serum beta 2-microglobulin (beta 2-MG) in comparison with serum creatinine, blood urea nitrogen and creatinine clearance in 164 patients with spinal cord injury. The value of serum beta 2-MG demonstrated the highest correlation coefficient (r = -0.927) in relation to creatinine clearance. The beta 2-MG value reflected the severity of hydronephrosis on excretory urography, with very few false negative values. The value of beta 2-MG is concluded to be one of the best screening tests in evaluating renal function in spinal cord injury patients.

Antenatal diagnosis and management of urinary abnormalities

Although much time, effort, and money have been expended in the area of fetal surgery and even though considerable unfortunate media publicity has resulted, the actual clinical problem is not one of great magnitude. Currently all those interested in this area agree that consideration of any intrauterine manipulation or surgery should be reserved for a fetus who has bilateral involvement that is progressive, destructive, and associated with oligohydramnios. Except for rare instances, this eliminates all fetuses except those with some type of urethral obstruction. Significant urethral obstruction accounts for approximately 10 per cent of all patients who have a prenatal diagnosis of a urologic abnormality. Of this 10 per cent, some will not be progressive, some will not be destructive, some will not involve both kidneys, and some will not develop oligohydramnios. Some of these patients will be diagnosed early enough in pregnancy to allow termination of the pregnancy if the involvement is significant and if termination is acceptable to the family. Some will be diagnosed late enough in pregnancy so that if the lungs are mature or can be stimulated to mature, early delivery and postnatal management can be elected. Some will have other associated lethal anomalies that can be diagnosed and would preclude any consideration of intrauterine manipulation or therapy. Some will have irreversible renal failure. Occasionally, the mother may refuse any proposed intrauterine therapy. Thus we are probably considering, on a theoretic basis, well under 1 per cent of all fetuses who have a prenatal diagnosis of urologic abnormalities. There may be some unusual situations that justify intrauterine manipulation. One that we encountered involved a fetus with an abdominal mass so large that a cesarean section was deemed necessary (Figs. 12 and 13). Aspiration of the mass just before delivery was performed to allow a vaginal delivery. Another case involved a pregnant woman who developed severe toxemia. The fetus was found to have a solitary renal cyst. Repeated aspirations of the cyst resulted in resolution of the toxemia, which promptly recurred when fluid reaccumulated in the fetal renal cyst. Insertion of a double-universe catheter from the cyst into the amniotic cavity allowed completion of the pregnancy, with the delivery of an otherwise normal fetus without recurrence of the toxemia. A recent report on fetal surgery from the International Fetal Surgery Registry, coauthored by the strongest advocate of intrauterine intervention, reached these conclusions.(ABSTRACT TRUNCATED AT 400 WORDS)

Diagnostic ultrasound: its value in acute urinary tract infection in spinal cord injury

Two cases of acute urinary tract infection in patients with spinal cord injury highlight the complications of calculus and perinephric abscess. Rather than waiting the customary 48 hours to assess response to antibiotics before evaluation for secondary complications, diagnostic ultrasound is advocated upon diagnosis of pyelonephritis. The potential benefits of early imaging seem to far outweigh the negligible risk and expense.

In-office ultrasonography to image the kidneys and bladder of children

We present the first experience with in-office ultrasonography to further the office evaluation of children with urological problems. Since February 1986 we imaged prospectively the kidneys and bladders of 172 children (100 boys and 72 girls, mean age 6 years) who presented for office evaluation using a portable 5 MHz. real-time linear array scanner. Initially, we gained familiarity with in-office ultrasonography by examining 38 children who presented for evaluation of problems not recognized to be associated with renal malformations (that is undescended testis). In-office ultrasonography showed hydronephrosis in 1 boy with a buried penis that was found later to be owing to ureteropelvic junction obstruction requiring pyeloplasty. Then, in-office ultrasonography was used to supplement the office evaluation of children with a history of urine infection, voiding problems or known malformations of the kidney and/or bladder. The test showed that 12 of 24 children (50 per cent) with a history of urine infection had a thickened detrusor, large bladder capacity with or without residual urine or reduced sensation to void. In-office ultrasonography also showed that 24 of 74 children (32 per cent) with voiding problems had a thickened detrusor, large bladder capacity with or without residual urine, fecal impaction, suspected bladder neck obstruction (which later required internal urethrotomy) or small bladder capacity. In 35 children with known malformations of the urinary tract in-office ultrasonography was useful to assess the progress of hydronephrosis (29) or to clarify the etiology of the hydronephrosis (4). The diagnostic value of this test was evaluated in 98 children in whom enough data were available to compare the results to those of subsequent urography or clinical outcome. In-office ultrasonography had a 98 per cent sensitivity and an 82 per cent specificity rate. We conclude that in-office ultrasonography is a reliable means to identify incomplete bladder emptying in children with urine infection related to dysfunctional voiding, identify detrusor thickening related to the unstable bladder and indicate the likely etiology of hydronephrosis.

Acute renal failure and acute hydronephrosis in pregnancy: use of the double-J stent

Images

Sonographic evaluation of renal stones treated by extracorporeal shock-wave lithotripsy

Real-time sonography was performed on 94 patients the day before and at 24 and 48 hr after extracorporeal shock-wave lithotripsy (ESWL) therapy. The ability of sonography to detect renal stones before ESWL, changes in the calculi after ESWL, and the occurrence of pre- and post-ESWL hydronephrosis was evaluated. Abdominal radiographs and linear renal tomography were used as the standard of comparison. Six other patients had sonography only either before or after ESWL. One hundred patients had a total 105 kidneys treated; 18 kidneys with more than three stones were not included. The other 87 kidneys had 102 stones evaluated by sonography before having ESWL; 66 stones (65%) were identified and 36 were not. Of those calculi not seen, 10 were less than or equal to 5 mm in diameter. Nineteen of the other 26 stones were in the ureter or at the ureteropelvic junction. Comparison of sonograms of 80 kidneys obtained before and after ESWL revealed no change in 37 (46%), more stones or fragments detected in 23 (29%), fewer stones or a change in location in 12 (15%), and an apparent decrease in the size of the original stone in eight (10%). Hydronephrosis was detected by pre-ESWL sonography in 16 kidneys (20%) and was noted to develop after ESWL in 20 (31%) of the 64 other kidneys. These results indicate that the ability of sonography to detect renal calculi is related not only to stone size but also to location. The clinical significance of pre- and post-ESWL hydronephrosis found by sonography must be considered in conjunction with the patient's symptoms, laboratory data, and other radiographic studies. Therefore, the routine use of sonography in the post-ESWL patient does not seem warranted.

Fetal hydronephrosis: selection and surgical repair

Newly developed diagnostic techniques allowed us to select a fetus with potentially reversible renal damage from the usually fatal group with bilateral hydronephrosis and severe oligohydramnios early in gestation. Fetal surgery to marsupialize the fetal bladder at 24 weeks gestation restored normal amniotic fluid dynamics and allowed sufficient pulmonary and renal development to insure survival after delivery near term.

Neonatal hydronephrosis in the era of sonography

During a 6-year period (1979-1985), 142 neonates with significant hydronephrosis were seen. Seventy-eight percent of the cases were discovered on fetal screening during obstetric sonography. Maternal/fetal intervention was virtually never indicated and most babies were asymptomatic. The most common conditions found were obstruction of the ureteropelvic junction (41%), obstruction of the distal ureter (usually primary megaureter) (23%), upper-pole hydronephrosis associated with duplex anomalies (13%), and posterior urethral valves (10%). Seventeen neonates with multicystic dysplastic kidney were seen (three per year or one for every eight with hydronephrosis). In comparison, during the 30-year period, 1947-1977, 146 neonates with significant hydronephrosis were seen. Most cases were discovered because the patients had signs and/or symptoms--either an abdominal mass (an enlarged kidney or bladder) or urosepsis. The three most common conditions were obstruction of the ureteropelvic junction (22%), posterior urethral valves (19%), and ectopic ureterocele (14%). During this period, 53 neonates with multicystic dysplastic kidney were discovered (two per year or one for every three with hydronephrosis). The dramatic increase in the number of neonates found to have hydronephrosis is primarily due to the widespread use of obstetric sonography and concomitant fetal screening. The pattern of causes before 1979 represented the incidence of symptomatic lesions. The current pattern more accurately reflects the true incidence of congenital anomalies of the urinary tract.