Necrosis of the allograft ureter--evaluation of different examination methods in early diagnosis

After renal transplantation, 16 of 1,109 patients (= 1.5%) developed an operatively confirmed necrosis of the allograft ureter. A review of these cases reveals that noninvasive ultrasonography, which was applied regularly with all patients, gave early indications of urologic complication. In cases of peritransplant fluid collection, renal transplant scintigraphy may be helpful in diagnosing a urinoma. In cases of renal graft failure with sonographic findings of perinephric fluid collection or hydronephrosis, antegrade pyelography--though more invasive--should always be performed given its low complication rate and improved visualization and pathological localization compared to other techniques. However, ureteral extravasation can be demonstrated only in cases of advanced necrosis; with necrosis just beginning and the wall still intact, frequently only the image of an obstruction is found.

What's new in pediatric uroradiology

The diagnosis and treatment of infants and children with urinary tract abnormalities have recently been affected by three developments. First, hydronephrosis can be detected in the fetus on obstetrical ultrasonography. Prenatal detection has resulted in a marked increase in the number of neonates referred for uroradiologic evaluation. Ureteropelvic junction (UPJ) obstruction, ureterovesical junction obstruction (UVJ), and reflux have been found to be the most common causes of hydronephrosis. Prophylactic antibiotics begun soon after delivery can prevent infection and its sequelae. Second, multicystic dysplastic kidney can now be accurately diagnosed preoperatively by a combination of ultrasonography and renal scintigraphy. This diagnostic certainty makes the decision to remove such a kidney a philosophical one. Third, it has been learned that reflux is sometimes familial. Nuclear cystography is an accurate and efficient method for screening asymptomatic family members.

Hydronephrosis in advanced ovarian carcinoma

In a consecutive series of 232 patients with ovarian carcinoma, (FIGO IIB-IV), receiving combination chemotherapy, 52 patients (22%) presented with (early, 69%) or developed (late, 31%) hydronephrosis diagnosed by intravenous pyelography or abdominal ultrasound scan. Unilateral hydronephrosis was seen in 77%, bilateral in 23%. Patients with hydronephrosis were characterized by stage IIIB-IV (67%), and primary residual tumor size greater than 2 cm (81%). Nine patients (17%) developed concomittantly impaired renal function diagnosed by a rise in se-creatinine and/or a decrease in 51Cr-EDTA clearance. No difference in survival was seen in patients with early or late hydronephrosis, nor with uni- or bilateral hydronephrosis, but patients with hydronephrosis at the start of chemotherapy lived significantly shorter than those without hydronephrosis, P less than .05. In conclusion, hydronephrosis is a common complication to advanced ovarian carcinoma, and the presence of this complication at the start of chemotherapy has a negative impact on survival.

[Urography and the isotopic renogram under diuresis enhance the diagnosis and the indication for therapy in congenital hydronephrosis]

Analysis of a group of 276 patients with congenital hydronephrosis by dysfunction of pyeloureteral function shows that in the most cases the diagnosis has to be established by corroborating the data given by urography, echography, and isotopic renogram. In the cases of controversial hydronephrosis diagnostic, urography and renogram under diuresis induction are very important in practice.

Maps for diagnosis and management of antenatal urinary tract dilatation

Despite advances in radiological imaging techniques, the ideal management of antenatally diagnosed hydronephrosis remains controversial. A map, showing diagnostic and management pathways, has been designed in an attempt to provide maximum information from the most appropriate and minimum number of investigations.

[Changes in the kidney and upper urinary tract in pathologic pregnancy follow-up. Results of an ultrasonic study]

In 201 women with pathologic course of pregnancy (161 women suffering from urinary tract infection, pyelonephritis and colic, 40 women with gestosis) the kidneys and the upper urinary tract were studied by means of ultrasonography. In 86% of the 161 women with colic, urinary tract infection and septic complications a dilation of the renal collecting system was found, in 39.4% of them a marked dilation (sagittal diameter of more than 15 mm). Frequency and grade of dilation have been uncreased from the first to the third trimenon, with a significant preference of the right side. In patients suffering from gestosis a lower frequency and grade of dilation was found. Pregnant women with a sagittal diameter of the pyelon of more than 15 mm should controlled more intensively prae and post partum, but the grade of dilation is not the only criterion of therapeutic strategies.

Ureteropelvic junction obstruction associated with ureteral hypoplasia

We present 3 cases in which a neonate had unilateral hydronephrosis associated with a ureter hypoplastic throughout its length. In all 3 infants the affected kidney failed to visualize on excretory urography and function of the kidney proved to be disappointing despite its relatively normal appearance on external examination. In each case significant renal dysplasia was present microscopically and ultimately the kidney had to be removed. A retrograde pyelogram should be considered whenever a hydronephrotic kidney in an infant fails to visualize, and if this shows a long hypoplastic ureter that cannot be bypassed easily associated renal dysplasia should be suspected and consideration given to nephrectomy rather than pyeloplasty as the primary treatment modality.

[Hydronephrosis and ureteropelvic junction syndrome. Apropos of 93 cases]

So called "congenital" hydronephrosis, a relatively frequent condition, is increasingly benefiting from modern investigative techniques such as ultrasound. This should enable a reduction in the time interval between clinical symptomatology and treatment. In a series of 93 cases, the authors demonstrate that pathological anatomy is of little value as regards etiology, while plastic surgery of the pyelo-ureteral junction still remains the most simple and reliable treatment with a low associated morbidity.

The fate of infant kidneys with fetal hydronephrosis but initially normal postnatal sonography

Antenatal hydronephrosis involving 49 renal units in 35 infants seen since 1984 was studied. Postnatal sonography performed in the first few days after birth confirmed upper tract dilatation in 39 kidneys (80 per cent) in 29 neonates and it was normal in 10 kidneys (20 per cent) in 6 neonates. Of the 6 neonates with a normal postnatal sonogram 5 underwent repeat renal sonography at an average of 2 months after birth, all showing moderate hydronephrosis (7 kidneys). Furosemide-enhanced diethylenetriaminepentaacetic acid renography was performed in 4 infants (5 kidneys) with ureteropelvic junction or megaureter obstruction, of whom 2 had persistent unilateral obstruction and underwent successful reconstructive surgery (1 pyeloplasty and 1 megaureter reimplantation). Two infants (3 kidneys) with nonobstructive dilatation are being followed while 1 infant with bilateral vesicoureteral reflux is being managed medically on long-term antimicrobial prophylaxis. Thus, 50 per cent of neonates with antenatal hydronephrosis and a normal postnatal sonogram performed during the first few days of life subsequently were found to have either significant obstruction (2 requiring surgery) or reflux. This study underscores the absolute necessity of followup sonography in all newborns with antenatal hydronephrosis that is not confirmed on the initial postnatal ultrasound.

Relationship between intermittent hydronephrosis and megacalicosis

Intermittent hydronephrosis is notoriously difficult to diagnose but, once confirmed, requires surgery. In contrast, congenital megacalicosis is accepted as a non-obstructive cause of upper urinary tract dilatation for which surgery is inappropriate. Experience with 2 cases and a review of the literature suggest that occasionally the clinical features and radiographic findings in the 2 conditions may overlap, leading to misdiagnosis. Attention to the combination of clinical features and radiography, together with the use of radionuclide techniques and acute pain studies, may help to distinguish between these conditions.

Idiopathic hydronephrosis: diagnosis, management and outcome

The results of the diagnosis, management and treatment of 50 consecutive patients presenting with renal pelvic dilatation suggestive of pelviureteric junction obstruction are presented. Modern assessment methods were used to investigate both pre-operative status and also the results of management of the 37 obstructed and 13 non-obstructive patients. The role and influence of the new assessment techniques on clinical decision making are discussed.

Grade I hydronephrosis: pulsed Doppler US evaluation

This study was undertaken to determine whether the presence of blood vessels could mimic the appearance of grade I hydronephrosis on sonograms and thus cause false-positive readings. One hundred consecutive patients with grade I hydronephrosis were examined. Sample volumes were obtained with pulsed Doppler ultrasonography (US) at the site of the greatest separation of the central renal sinus echoes to determine if the separation was fluid accumulating in the collecting system, as in obstruction, or if the separation was actually caused by vessels that mimic hydronephrosis. Vascular structures accounted for the separation of the sinus echoes in 43% of patients. In patients 12 years of age or younger, this frequency rose to 61%. The simple procedure of evaluating the renal sinus echo separation with pulsed Doppler US should decrease the frequency of false-positive diagnoses of hydronephrosis and thus diminish the need for further confirmatory testing.

The evaluation of suspected renal colic: ultrasound scan versus excretory urography

Patients commonly present to the emergency department with a suspected diagnosis of renal colic. A prospective study of 98 patients presenting with acute flank or abdominal pain or both was conducted to determine the diagnostic accuracy of ultrasound scan compared with excretory urography for the diagnosis of urinary tract calculi. All patients underwent standardized ultrasound scan and excretory urography as independent procedures. Two staff radiologists who reported the procedures were blinded to the results of the other diagnostic test and ultimate clinical outcome. All patients discharged home from the ED were followed to the hospital urology clinic. The diagnosis of urinary calculus was made only by identification of calculus at surgery or by reported passage of a stone by the patient. Of 85 patients available for follow-up study (56 men, 29 women; mean age, 40.5 years; range 18 to 77 years), calculi were identified in 69 (81%). Ultrasound identified calculi in 44 patients (sensitivity, 64%; specificity, 100%). Excretory urography identified calculi in 44 patients (identical sensitivity and specificity). When the presence of obstructive hydronephrosis only was used to diagnose renal calculi, ultrasound scan identified 59 patients (sensitivity, 85%; specificity, 100%) and excretory urography identified 62 patients (sensitivity, 90%; specificity, 94%). When the results of both diagnostic modalities were combined, calculi were identified in 59 patients (sensitivity, 85%; specificity, 100%) and hydronephrosis was seen in 66 patients (sensitivity, 95%; specificity, 94%). Our study shows that the diagnostic abilities of these procedures are equal in the detection of renal calculi.(ABSTRACT TRUNCATED AT 250 WORDS)

Duplex Doppler US of the kidney: differentiation of obstructive from nonobstructive dilatation

Distinction of the obstructed from the nonobstructed dilated renal collecting system is a difficult problem often requiring interventional procedures and pressure measurements. The authors prospectively performed duplex Doppler ultrasound (US) evaluations in 21 kidneys (obstructed, n = 14; nonobstructed, n = 7) immediately before percutaneous nephrostomy. In addition, ten of the obstructed kidneys were evaluated with follow-up Doppler US after percutaneous nephrostomy. Renal obstruction caused a change in the Doppler waveform detected by means of the resistive index (RI). Thirteen of the 14 obstructed kidneys had a RI value greater than .70, while none of the nonobstructed kidneys had a RI value exceeding .70. Relief of the obstruction resulted in a reduced RI; in nine of ten kidneys, the RI was less than or equal to .70 (similar to that of the nonobstructed kidneys). When a dilated collecting system is being imaged, additional evaluation with duplex Doppler US may help distinguish obstructed from nonobstructed dilatation, which may be of particular benefit in patients with conditions that usually predispose them to collecting system dilatation.

[Diagnosis in neonatal hydronephrosis]

Maternal ultrasonography makes it possible to detect hydronephrosis in the fetus. After birth, hydronephrosis should be confirmed by repeating the ultrasonic examination. Reflux may coexist with all causes of hydronephrosis, for which reason it is necessary to do a voiding cystourethrogram. It is also necessary to do a renography, partly to estimate the relative renal function of each kidney, and partly to estimate the drainage function. In most cases ultrasound, voiding cystourethrography and renography are able to reveal the cause of hydronephrosis. Only in case of doubt it is necessary to do an excretory urography, which is rendered difficult by excessive bowel gas and poor renal function in neonates.

[2 cases of intermittent hydronephrosis--usefulness of ultrasonography]

Case 1: An 8-year-old boy consulted our clinic complaining of left flank colicky pain. He had a past history of the same episode. Ultrasonographic study was promptly performed. Left hydronephrosis was detected. At operation, left aberrant renal vessel was resected, and he has been free of pain. Case 2: A 65-year-old woman consulted our clinic because of abdominal pain and fever, who occasionally had the same episode. The existence and disappearance of the right hydronephrosis could be observed by emergency ultrasonography and following ultrasonic study, and the stenosis of the right lower ureter caused of cystitis cystica and glandularis was pointed out by retrograde ureterography. Diuresis ultrasonography by furosemide was performed to evaluate urinary tract stricture. In case 1, an incomplete obstruction pattern was obtained after operation, and in case 2, a complete obstruction pattern was shown. The emergency ultrasonography and diuresis ultrasonography were useful for the diagnosis and observation of intermittent hydronephrosis.

Intravenous pyelography in children with urinary tract infection and vesicoureteral reflux

In a previous study of the radiologic evaluation of children with urinary tract infection it was recommended that IVP be performed in all patients with either abnormal ultrasonographic or voiding cystourethrographic findings. However, the benefit from IVP was believed to be questionable in children with normal ultrasonography findings and vesicoureteral reflux of only a low grade (I or II of V). To gain a better understanding of the need for IVP in the radiologic evaluation of such children, the database was expanded and the findings concerning ultrasonography and IVP were analyzed in 52 children with urinary tract infection and vesicoureteral reflux seen during the last 3 years. Of a total of 72 instances of reflux, 44 (61.1%) were of low grade (I or II), 14 of medium grade (III), and 14 of high grade (IV or V). Of the 44 urinary systems with low-grade reflux, results were as follows: renal ultrasonography appeared normal in 38 and in 34 of these, the IVP also appeared normal; in the other four, only minor and negligible changes were seen with IVP. Surgical intervention was not necessary in any of these 38 urinary systems. In six systems with low-grade vesicoureteral reflux but with abnormal ultrasonography findings, IVP results were also abnormal, and surgery was necessary in two instances. Of the 14 urinary systems with medium-grade reflux, ultrasonography appeared normal in ten but in six of these the IVP appeared abnormal.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical aspects of hydronephrosis in Khartoum

Two hundred and thirty two patients with hydronephrosis were managed during the period 1982 to 1987. The peak incidence occurred between 20 and 30 years of age. 29% of the patients had history of urinary bilharziasis at presentation. Intravenous urography (IVU) was performed in 227 (98%) patients and it was diagnostic in 83% of them. Ultrasonography, retrograde and antegrade pyelography were among other methods of investigations. Hydronephrosis was bilateral in 56 patients. The commonest cause of hydronephrosis were idiopathic pelvi-ureteric junction obstruction, urinary bilharziasis and retroperitoneal fibrosis. 206 patients required surgical intervention to relieve obstruction. 184 patients attended the follow-up clinics for 6 months or more. The findings of the post-operative follow-up IVU are discussed.

The Whitaker test: experimental analysis in a canine model of partial ureteric obstruction

The Whitaker test has been described as a means of reaching a diagnosis in equivocal upper urinary tract obstruction, but there has been conflicting evidence regarding the validity of this test. The present study assesses the reliability of the test in an experimental model which creates an accurate and predetermined degree of partial obstruction of the ureter. The Whitaker test was performed using the standard perfusion rate of 10 ml./min. in male adult dogs using a long-term indwelling renal intrapelvic cannula before and after application of ureteric obstruction, and after one month. Control animals underwent a sham procedure. Results of in vivo and in vitro perfusion studies were compared. Perfusion studies at multiple flow rates were also performed. The Whitaker test reliably detected the presence of ureteric obstruction and the degree of partial obstruction could be determined. Multiple flow rate studies did not significantly improve test results. Provoked pressures in the highest grade of obstruction were less than expected and this may be due to pyelovenous reflux.

Rapid, contrast-enhanced, diuretic magnetic resonance imaging of unilateral partial ureteral obstruction. An experimental study in micropigs

The value of rapid, contrast-enhanced, diuretic magnetic resonance (MR) imaging (using ferrioxamine B and furosemide) in demonstrating partial unilateral ureteral obstruction and the potential of such MR imaging in differentiating obstructive from nonobstructive hydronephrosis was assessed in six micropigs. MR imaging (0.35 Tesla, partial-flip technique with repetition time [TR] of 125 milliseconds, echo-delay time [TE] of 20 milliseconds, and flip angle of 70 degrees) was performed before, and at 5, 12, and 19 days after partial ureteral obstruction. Additionally, MR images were acquired 5, 12, and 19 days after release of obstruction. The diuretic was injected 10 minutes after the contrast medium. MR findings were correlated with results from nuclear scintigraphy (99mTc-DMSA uptake). MR images provided good morphologic detail from which renal size, parenchymal thickness, and degree of hydronephrosis could be determined. Contrast medium allowed assessment of cortical uptake and urinary excretion. The course of cortical signal enhancement best characterized the difference between obstructive and nonobstructive hydronephrosis. Normal kidneys and kidneys with nonobstructive hydronephrosis showed progressive decrease in cortical signal enhancement (-11.7% within 40 minutes) after furosemide injection. The kidneys with obstructive hydronephrosis demonstrated a plateau of signal enhancement without decrease (-0.7% within 40 minutes). These results demonstrate the utility of rapid contrast-enhancing, diuretic MR imaging in differentiating obstructive from nonobstructive hydronephrosis.

Pleural effusion and hydronephrosis in a newborn

While the association of obstructive uropathy with ascites has been known since 1863, and with pleural effusion since 1954, the latter combination remains rare. This case report describes a male newborn with a massive left pleural effusion that was caused by same-sided hydronephrosis from obstructing posterior urethral valves. The effusion disappeared within a few days after adequate urinary drainage was established, and the infant was remained well since the abnormal urethral valves were fulgurated cystoscopically. Review of the clinical and experimental literature reveals no consensus about how pleural fluid accumulates in the presence of obstructive uropathy, and this neonate showed a direct inverse relation between the amount of pleural fluid drainage and urinary output via catheter. Hydronephrosis should be considered diagnostically when a newborn has a pleural effusion that is otherwise unexplained.

Pyelonephritis complicating relapsing acute pancreatitis

A case of right pyelonephritis with hydronephrosis complicating relapsing acute pancreatitis and right pararenal phlegmon formation is presented. Hydronephrosis is a reportedly rare complication of extrapancreatic inflammation; the only 6 previous cases involving the right side are reviewed. The present case report, to our knowledge, is the first to describe clinical and laboratory evidence of pyelonephritis secondary to partial obstruction of the right upper renal tract by an extrapancreatic phlegmon. The clinician caring for patients with acute pancreatitis should be aware of this important complication, since the presentation of pyelonephritis-flank pain and fever--could erroneously be attributable solely to the pancreatitis.