The terms \"renal regenerating nodule\" and \"nodular compensatory hypertrophy\" are used in the literature to describe functioning pseudo-tumors (FPT) in the setting of an extensively scarred kidney. FPTs are usually discovered incidentally during routine renal imaging. Differentiating these FPTs from renal neoplasms is critical but can be challenging in the setting of chronic kidney disease (CKD) given the limitations related to using contrast-based imaging.
We report a pediatric case series of 5 CKD patients, with history of urinary tract infections, in which tumor-like lesions evolved in scarred kidneys and were incidentally discovered on routine renal imaging. These were diagnosed as FPT by utilizing dimercaptosuccinic acid (DMSA) imaging and showed stable size and appearance upon follow-up with ultrasound and MRI.
FPTs can be picked up on routine imaging of pediatric patients with CKD. Although larger cohort studies are needed to confirm these conclusions, our case series supports the evidence that DMSA scan showing uptake at the site of the mass can be a useful tool to suggest the diagnosis of FPTs in children with kidney scarring, and that SPECT DMSA scan adds more precision in picking up and accurately localizing FPTs compared to planar DMSA.

BACKGROUND: Nephrotoxicity is a prevalent consequence of cancer treatment using radiotherapy and chemotherapy or their combination. There are two methods; histological and biochemical, to assess the kidney damage caused by toxic agents in animal studies. Although these methods are used for the try-out of renoprotective factors, these methods are invasive and time-consuming, and also, lack the necessary sensitivity for primary diagnosis. Quantitative renal 99mTc-DMSA scintigraphy is a noninvasive, precise and sensitive radionuclide technique which is used to assess the extent of kidney damage, so that the extent of injury to the kidney will be indicated by the renal uptake rate of 99mTc-DMSA in the kidney. In addition, this scintigraphy evaluates the effect of the toxic agents by quantifying the alterations in the biodistribution of the radiopharmaceutical.
CONCLUSIONS: In this review, the recent findings about the renoprotective agents were evaluated and screened with respect to the use of 99mTc-DMSA , which is preclinically and clinically used for animal cases and cancer patients under the treatment by radiotherapy and chemotherapy.

OBJECTIVE: To analyze the management of prenatal urinoma and ureteropelvic junction obstruction (UPJO) postnatally by a case report and literature review.
METHODS: We report a case of an UPJO and urinoma in a newborn. After birth, renal function was absent, and nephrectomy was performed. The literature from 1985 to date has been reviewed.
CONCLUSIONS: By the analysis of the literature, we can observe mainly, that prenatally diagnosed urinoma and UPJO are managed conservatively. After birth, different attitudes have been carried out, independently of residual renal function, such as radical or reconstructive surgery, or conservative treatment.
CONCLUSIONS: Intrauterine management is not indicated. Urinary diversion is indicated in symptomatic cases secondary to renal trauma or endoscopic procedure. In non-functional kidney, nephrectomy is indicated.

BACKGROUND: Most primary non-refluxing megaureters resolve spontaneously and the indications for surgery are not sufficiently well established.
OBJECTIVE: To analyze the clinical features, treatment and outcome of asymptomatic primary non-refluxing megaureter.
METHODS: We retrospectively studied 58 infants with primary non-refluxing megaureter. The diagnostic methods used were renal ultrasound, renal isotopic renogram, DMSA scan, and evaluation of renal function.
RESULTS: The mean age at postnatal diagnosis was 24 days. The mean follow-up was 4 years. Sixty-nine percent of the patients were male. Fifty-seven percent were left megaureters and 22% were bilateral (71 affected renal units). Eleven percent of megaureters were grade I, 48% were grade II, and 41% were grade III. Only nine patients (15%) received surgical treatment. The indications for surgical treatment were severe megaureter (3/9 patients; 33%), prolonged T1/2 (3/9 patients; 33%), reduced function (1/9 patients; 11%), prolonged T1/2 plus reduced function (1/9 patients; 11%) and increased dilation (1/9 patients; 11%). The mean age at surgery was 7 months. Outcomes in the non-surgical group (85% of the patients; 60 renal units) were as follows: 90% of megaureters were corrected or improved on ultrasound scan and 10% showed no change. In the first renogram, function was low in 4/60 kidneys (7%) and T1/2 was prolonged in 3/60 (5%). Finally, all kidneys in the non-surgical group had normal function, except one, which was injured from the beginning. T1/2 was normal in all kidneys. Outcomes in the surgical group (10 megaureters) were as follows: 80% of megaureters were corrected or improved after surgical intervention and 20% showed no change. At diagnosis, 4/10 kidneys (40%) had reduced function. In the post-surgical renogram 2/10 kidneys (20%) continued to show reduced function, 1/10 kidney (10%) showed restored renal function, and 1/10 kidney (10%) was nephrectomized. Initial T1/2 was prolonged in 4/10 patients (40%), and after surgery T1/2 was normal in all patients. The final DMSA scan showed 5/71 kidneys (7%) with irreversible damage (one slightly injured, two moderately injured, and three severely injured). The remaining 66 kidneys were normal. Overall renal function and blood pressure were normal in all patients.
CONCLUSIONS: Primary non-refluxing megaureter is usually a functional and benign congenital malformation that resolves during the first months of life. Although the malformation can persist, only a few patients require surgical treatment. Most authors agree that initial treatment should not be surgical and that surgery should be reserved for patients who develop ureteral dilation, a decrease in differential renal function, and/or severe symptoms during follow-up. In a few patients (7% of our series), the renal unit belonging to the megaureter shows irreversible congenital injury. In these patients, surgery is not useful.

Renal nuclear medicine is used to evaluate renal function and morphology. Renal scintigraphy is the best imaging modality for evaluation of functional parameters such as glomerular filtration rate and effective renal plasma flow. The commonly used renal radiopharmaceuticals are reviewed. Both imaging and non-imaging techniques are presented. Specific applications of renal nuclear medicine are discussed.

OBJECTIVE: Reports of previous studies using excretory urography indicate that significant numbers of new scars developed in 5 to 31% of cases and scarring progressed in 11 to 16% after antireflux surgery. We evaluated renal scarring after surgery using a more accurate method, that is dimercapto-succinic acid renal scintigraphy.
METHODS: Between 1985 and 1997 antireflux surgery was performed for primary vesicoureteral reflux in 223 children at our hospital. Of these patients 45 boys and 29 girls with a median age of 74 months at surgery in whom preoperative and postoperative renal scans were available form the basis of our retrospective study. Renal scan was performed 0.3 to 58 months (median 2) preoperatively and 5.3 to 44 months (median 18.7) postoperatively. A total of 24 children (39 renal units) were followed further by additional scanning for as long as 25 to 120 months (median 43.2) postoperatively. Each scan was blindly reviewed for the size, number and zone location of cortical defects based on morphology. Interval changes were grouped into categories as improved, no change, progressed and new scar formation.
RESULTS: Postoperatively there was no ureteral obstruction. Pyelonephritis developed in 2 patients (2.7%) and asymptomatic bacteriuria was noted in 35 (47.3%) postoperatively. Of the renal units 110 (86.6%) showed no change, while 15 (11.8%) were improved and 2 (1.6%) had progression. In no case was new renal scar formation observed.
CONCLUSIONS: Contrary to most previous reports involving excretory urography, our results indicate no significant progression of renal scarring after antireflux surgery. In most cases postoperative followup renal scans demonstrated no significant morphological change. When there was change, it mostly involved the disappearance or decrease of renal scars.

It is now widely accepted that children with a proven urinary tract infection should undergo some form of diagnostic imaging to assess the presence of, or the potential to develop, renal scarring. The type of investigation which should be performed is controversial. Some centres still perform intravenous urography, others rely on ultrasound alone, while others believe that a 99Tc(m)-dimercaptosuccinic acid (99Tc(m)-DMSA) scan is essential. This review discusses the advantages and disadvantages of these techniques by drawing from the extensive literature currently available. The consensus view is that a DMSA scan is the most sensitive method of detecting renal scarring and of highlighting the kidney at risk of developing scarring. It is hoped that wider early use of DMSA scintigraphy will lead to a fall in the number of children who develop end-stage renal disease.

暂无摘要。

Measurement of kidney depths using computed axial tomographic (CAT) scans, considered as the gold standard, has been compared in 25 patients with depth measured using an isotopic method (99Tcm-DMSA). 99Tcm-DMSA underestimates renal depth in 78% of the cases (mean underestimation: 0.78 cm). The correlation coefficient between the two methods is 0.82. As a comparison, kidney depths calculated using Tonnesen\'s formula are also given and related to CAT scan results. The presence of renal morphological abnormalities in 18% of the studied kidneys allowed the authors to study their potential influence on 99TcmDMSA measurements. They do not seem to be very different from those obtained in morphologically normal kidneys. The different methods for kidney depth measurement described in the literature are briefly reviewed.