Hydronephrotic lower moiety of duplex systems: Observations using diuresis renography.

PURPOSE: The purpose of this study is to characterize the prevalence and behavior of hydronephrosis of non-refluxing lower moiety of duplex kidneys using MAG-3 diuresis renography. We compare our data to previous case series and ureteropelvic junction obstruction of single systems. MATERIALS AND METHODS: An IRB-approved database of over 5000 diuresis renograms performed in 2025 patients was queried to identify cases of hydronephrosis of lower moiety of duplex kidneys suspicious for ureteropelvic obstruction, excluding those with hydroureter or reflux. Kidney function and post-furosemide drainage parameters on initial and follow-up diuresis renograms were recorded. Medical records and patient outcomes were reviewed. RESULTS: In total, 19 renal units were identified in 18 patients (11 male, 7 female), age range 0.5 months to 17.8 years, including one patient with bilateral lower moiety hydronephrosis. Initial diuresis renograms in 12 asymptomatic patients (13 renal units) with antenatal hydronephrosis demonstrated varying drainage patterns from normal to obstructed. Follow-up studies showed worsening drainage in 3 patients, who all underwent surgery. Drainage improved in 4 patients and remained unchanged in 5 patients (6 renal units). Of the 6 patients presenting with Dietl's crisis, 5 showed obstructive drainage on initial diuresis renogram, 2/5 with decreased function. All 5 obstructed patients underwent surgery. CONCLUSION: Hydronephrosis of the lower moiety of a duplex system is rare and behaves similarly to single systems. The majority are diagnosed antenatally, display a dynamic nature, and may present with acute obstruction. Diuresis renography is a valuable tool in its evaluation and management.

Corticosteroids to prevent kidney scarring in children with a febrile urinary tract infection: a randomized trial.

BACKGROUND: To evaluate the efficacy of adjuvant systemic corticosteroids in reducing kidney scarring. A previous study suggested that use of adjuvant systemic corticosteroids reduces kidney scarring in children radiologically confirmed to have extensive pyelonephritis. Efficacy of corticosteroids for children with febrile urinary tract infection (UTI) has not been studied. METHODS: Children aged 2 months to 6 years with their first febrile UTI were randomized to corticosteroids or placebo for 3 days (both arms received antimicrobial therapy); kidney scarring was assessed using 99mTc-dimercaptosuccinic acid kidney scan 5-24 months after the initial UTI. RESULTS: We randomized 546 children of which 385 had a UTI and 254 had outcome kidney scans (instead of the 320 planned). Rates of kidney scarring were 9.8% (12/123) and 16.8% (22/131) in the corticosteroid and placebo groups, respectively (p = 0.16), corresponding to an absolute risk reduction of 5.9% (95% confidence interval: - 2.2, 14.1). CONCLUSION: While children randomized to adjuvant corticosteroids tended to develop fewer kidney scars than children who were randomized to receive placebo, a statistically significant difference was not achieved. However, the study was limited by not reaching its intended sample size. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov , NCT01391793, Registered 7/12/2011 Graphical abstract.

Gastric emptying of milk in infants and children up to 5 years of age: normative data and influencing factors.

BACKGROUND: Gastric emptying scintigraphy is widely used in infants and children, but there is a lack of age-specific normative data. OBJECTIVE: The objectives of this retrospective study were: 1) to establish a range of gastric emptying of milk or formula as a surrogate for normal gastric emptying in infants and young children ≤5 years of age, and 2) to investigate the effects of patient age, feeding volume, feeding route and gastroesophageal reflux on gastric emptying. MATERIALS AND METHODS: The reports of 5,136 gastric emptying studies of children ≤5 years of age performed at Children's National Medical Center from January 1990 to August 2012 were reviewed. Demographic data, 1-h and 3-h gastric emptying values and gastroesophageal reflux status of all patients were stored in a database. Using stringent inclusion and exclusion criteria, the studies of patients as similar to healthy children as possible were selected for this study. RESULTS: The study group included 2,273 children (57% male) ages 0-59 months (median: 4.6 months). The median 1-h gastric emptying was 43% (interquartile range [IQR] 34-54%). The median 3-h gastric emptying was 91% (IQR 79-98%). Sixty-one percent of patients with 1-h gastric emptying value of <50% had 3-h gastric emptying ≥80%. Gastric emptying was significantly faster in children ≤6 months as compared with all older age groups. In each age group, the median gastric emptying decreased with increasing feeding volume. Gastric emptying was significantly faster in patients fed via combined nasogastric tube and oral routes as compared with those fed exclusively orally. There was no significant difference in gastric emptying of children with and without gastroesophageal reflux. CONCLUSION: Although there are statistically significant differences in gastric emptying based on age, volume and route of feeding, the data suggest that overall normal liquid gastric emptying in infants and children ≤5 years of age is ≥80% at 3 h. One-hour emptying measurements are not reliable for detecting delayed gastric emptying.

Biomarkers that differentiate false positive urinalyses from true urinary tract infection.

BACKGROUND: The specificity of the leukocyte esterase test (87%) is suboptimal. The objective of this study was to identify more specific screening tests that could reduce the number of children who unnecessarily receive antimicrobials to treat a presumed urinary tract infection (UTI). METHODS: Prospective cross-sectional study to compare inflammatory proteins in blood and urine samples collected at the time of a presumptive diagnosis of UTI. We also evaluated serum RNA expression in a subset. RESULTS: We enrolled 200 children; of these, 89 were later demonstrated not to have a UTI based on the results of the urine culture obtained. Urinary proteins that best discriminated between children with UTI and no UTI were involved in T cell response proliferation (IL-9, IL-2), chemoattractants (CXCL12, CXCL1, CXCL8), the cytokine/interferon pathway (IL-13, IL-2, INFγ), or involved in innate immunity (NGAL). The predictive power (as measured by the area under the curve) of a combination of four urinary markers (IL-2, IL-9, IL-8, and NGAL) was 0.94. Genes in the pathways related to inflammation were also upregulated in serum of children with UTI. CONCLUSIONS: Urinary proteins involved in the inflammatory response may be useful in identifying children with false positive results with current screening tests for UTI; this may reduce unnecessary treatment.

Host and Bacterial Markers that Differ in Children with Cystitis and Pyelonephritis.

OBJECTIVE: To determine whether treatment for urinary tract infections in children could be individualized using biomarkers for acute pyelonephritis. STUDY DESIGN: We enrolled 61 children with febrile urinary tract infections, collected blood and urine samples, and performed a renal scan within 2 weeks of diagnosis to identify those with pyelonephritis. Renal scans were interpreted centrally by 2 experts. We measured inflammatory proteins in blood and urine using LUMINEX or an enzyme-linked immunosorbent assay. We evaluated serum RNA expression using RNA sequencing in a subset of children. Finally, for children with Escherichia coli isolated from urine cultures, we performed a polymerase chain reaction for 4 previously identified virulence genes. RESULTS: Urinary markers that best differentiated pyelonephritis from cystitis included chemokine (C-X-C motif) ligand (CXCL)1, CXCL9, CXCL12, C-C motif chemokine ligand 2, INF γ, and IL-15. Serum procalcitonin was the best serum marker for pyelonephritis. Genes in the interferon-γ pathway were upregulated in serum of children with pyelonephritis. The presence of E coli virulence genes did not correlate with pyelonephritis. CONCLUSIONS: Immune response to pyelonephritis and cystitis differs quantitatively and qualitatively; this may be useful in differentiating these 2 conditions.

Early Detection of Ureteropelvic Junction Obstruction Using Signal Analysis and Machine Learning: A Dynamic Solution to a Dynamic Problem.

PURPOSE: We sought to define features that describe the dynamic information in diuresis renograms for the early detection of clinically significant hydronephrosis caused by ureteropelvic junction obstruction. MATERIALS AND METHODS: We studied the diuresis renogram of 55 patients with a mean ± SD age of 75 ± 66 days who had congenital hydronephrosis at initial presentation. Five patients had bilaterally affected kidneys for a total of 60 diuresis renograms. Surgery was performed on 35 kidneys. We extracted 45 features based on curve shape and wavelet analysis from the drainage curves recorded after furosemide administration. The optimal features were selected as the combination that maximized the ROC AUC obtained from a linear support vector machine classifier trained to classify patients as with or without obstruction. Using these optimal features we performed leave 1 out cross validation to estimate the accuracy, sensitivity and specificity of our framework. Results were compared to those obtained using post-diuresis drainage half-time and the percent of clearance after 30 minutes. RESULTS: Our framework had 93% accuracy, including 91% sensitivity and 96% specificity, to predict surgical cases. This was a significant improvement over the same accuracy of 82%, including 71% sensitivity and 96% specificity obtained from half-time and 30-minute clearance using the optimal thresholds of 24.57 minutes and 55.77%, respectively. CONCLUSIONS: Our machine learning framework significantly improved the diagnostic accuracy of clinically significant hydronephrosis compared to half-time and 30-minute clearance. This aids in the clinical decision making process by offering a tool for earlier detection of severe cases and it has the potential to reduce the number of diuresis renograms required for diagnosis.

Prediction of Clinical Outcomes in Prenatal Hydronephrosis: Importance of Gravity Assisted Drainage.

PURPOSE: In infants with SFU (Society for Fetal Urology) grade 3-4 congenital hydronephrosis, 99mTc-mercaptoacetyltriglycine diuretic renography assesses differential function and drainage half-time. We routinely also include the percent of radiotracer drained after 30 minutes of diuresis as well as after 15 minutes with the patient in the upright position. We investigated whether any 1 or more of these parameters on initial diuretic renography predicts persistent or worsening drainage parameters. MATERIALS AND METHODS: Infants 6 months or younger with grade 3-4 congenital hydronephrosis who presented between January 2009 and December 2014 were identified from billing data and included in analysis if they underwent at least 1 baseline diuretic renography. Those with structural anomalies were excluded from study. Baseline and followup differential function, diuresis half-time, clearance at 30 minutes and clearance with the patient upright were abstracted and comparisons were made between those with initially indeterminate diuresis half-time who underwent pyeloplasty vs those showing spontaneous improvement. RESULTS: A total of 74 patients (82 renal units) with presumed ureteropelvic junction obstruction met inclusion/exclusion criteria. All 10 renal units with initial diuresis half-time less than 5 minutes resolved spontaneously and all 25 renal units with initial diuresis half-time greater than 75 minutes underwent pyeloplasty. Therefore, we defined the indeterminate group as the 47 renal units with initial half-time between 5 and 75 minutes. Of those 47 renal units with indeterminate initial diuresis half-time 23 (47%) underwent pyeloplasty and 25 (53%) resolved spontaneously. Indications for pyeloplasty included worsening in 17 cases, persistent obstruction in 4 and urinary tract infection in 1. Among renal units with indeterminate drainage clearance while upright and clearance at 30 minutes were the only variables that differed significantly between surgical cases and those that resolved spontaneously. CONCLUSIONS: Radiotracer clearance with the patient upright and clearance at 30 minutes are more predictive of surgical management than diuresis half-time or differential function for renal units with indeterminate drainage. They should be included in the standard assessment of ureteropelvic junction obstruction.

Glomerular hyperfiltration in children with cancer: prevalence and a hypothesis.

BACKGROUND: Glomerular hyperfiltration has recently been reported in children with malignancies and has been attributed to increased solute from breakdown of tumor tissues. OBJECTIVE: To evaluate the prevalence of hyperfiltration in the pediatric oncology population and explore its pathophysiological mechanism. MATERIALS AND METHODS: Tc-99 m diethylenetriaminepentaacetic acid (DTPA) glomerular filtration rate (GFR) examinations (437 studies) and medical records of 177 patients <21 years of age diagnosed with a malignancy between January 2005 and October 2013 were retrospectively reviewed. Hyperfiltration was defined as a GFR ≥ 160 ml/min/1.73 m2. RESULTS: Seventy-seven (43.5%) patients had hyperfiltration in at least one GFR exam. A significantly higher percentage of patients with central nervous system (CNS) tumors (63.6%) had hyperfiltration when compared to other tumor types (27.3%, P < 0.001). No association was found between hyperfiltration and age, gender, race or bone marrow involvement. There was a significant trend toward decreasing hyperfiltration after the second cycle of chemotherapy (P = 0.006) and a significant increase in subjects with low GFR (<100 ml/min/1.73 m2) with increasing number of cycles of chemotherapy (P = 0.005). CONCLUSION: Glomerular hyperfiltration is common in children with malignancies at diagnosis and during initial cycles of chemotherapy. It is particularly prevalent in patients with central nervous tumors, which are frequently smaller in volume. Therefore, the pathophysiological mechanism of hyperfiltration cannot be explained solely on the basis of large tumor volume and subsequent cell breakdown. We hypothesize that host hypermetabolic state plays an important role in pathophysiology of hyperfiltration.

Early Antibiotic Treatment for Pediatric Febrile Urinary Tract Infection and Renal Scarring.

IMPORTANCE: Existing data regarding the association between delayed initiation of antimicrobial therapy and the development of renal scarring are inconsistent. OBJECTIVE: To determine whether delay in the initiation of antimicrobial therapy for febrile urinary tract infections (UTIs) is associated with the occurrence and severity of renal scarring. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study that combined data from 2 previously conducted longitudinal studies (the Randomized Intervention for Children With Vesicoureteral Reflux trial and the Careful Urinary Tract Infection Evaluation Study). Children younger than 6 years with a first or second UTI were followed up for 2 years. EXPOSURE: Duration of the child's fever prior to initiation of antimicrobial therapy for the index UTI. MAIN OUTCOMES AND MEASURES: New renal scarring defined as the presence of photopenia plus contour change on a late dimercaptosuccinic acid renal scan (obtained at study exit) that was not present on the baseline scan. RESULTS: Of the 482 children included in the analysis, 434 were female (90%), 375 were white (78%), and 375 had vesicoureteral reflux (78%). The median age was 11 months. A total of 35 children (7.2%) developed new renal scarring. Delay in the initiation of antimicrobial therapy was associated with renal scarring; the median (25th, 75th percentiles) duration of fever prior to initiation of antibiotic therapy in those with and without renal scarring was 72 (30, 120) and 48 (24, 72) hours, respectively (P = .003). Older age (OR, 1.03; 95% CI, 1.01-1.05), Hispanic ethnicity (OR, 5.24; 95% CI, 2.15-12.77), recurrent urinary tract infections (OR, 0.97; 95% CI, 0.27-3.45), and bladder and bowel dysfunction (OR, 6.44; 95% CI, 2.89-14.38) were also associated with new renal scarring. Delay in the initiation of antimicrobial therapy remained significantly associated with renal scarring even after adjusting for these variables. CONCLUSIONS AND RELEVANCE: Delay in treatment of febrile UTIs and permanent renal scarring are associated. In febrile children, clinicians should not delay testing for UTI.

Renal Scarring in the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) Trial.

BACKGROUND AND OBJECTIVES: The main objectives of the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial were to evaluate the role of antimicrobial prophylaxis in the prevention of recurrent urinary tract infection (UTI) and renal scarring in children with vesicoureteral reflux (VUR). We present a comprehensive evaluation of renal scarring outcomes in RIVUR trial participants. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This multicenter, randomized, placebo-controlled trial enrolled 607 children aged 2-71 months with grade 1-4 VUR diagnosed after a first or second febrile or symptomatic UTI. Study participants received trimethoprim-sulfamethoxazole or placebo and were followed for 2 years. Renal scarring was evaluated by baseline and follow-up (99m)technetium dimercaptosuccinic acid (DMSA) renal scans that were reviewed independently by two blinded reference radiologists. RESULTS: At the end of the study, 58 (10%) of 599 children and 63 (5%) of 1197 renal units had renal scarring. New renal scarring did not differ between the prophylaxis and placebo groups (6% versus 7%, respectively). Children with renal scarring were significantly older (median age, 26 versus 11 months; P=0.01), had a second UTI before enrollment (odds ratio [OR], 2.85; 95% confidence interval [95% CI], 1.38 to 5.92), were more likely to be Hispanic (OR, 2.22; 95% CI, 1.13 to 4.34), and had higher grades of VUR (OR, 2.79; 95% CI, 1.56 to 5.0). The proportion of new scars in renal units with grade 4 VUR was significantly higher than in units with no VUR (OR, 24.2; 95% CI, 6.4 to 91.2). CONCLUSIONS: Significantly more renal scarring was seen in relatively older children and in those with a second episode of febrile or symptomatic UTI before randomization. Preexisting and new renal scars occurred significantly more in renal units with grade 4 VUR than in those with low-grade or no VUR. Antimicrobial prophylaxis did not decrease the risk of renal scarring.

The "flowerpot" sign: inference of poor renal function in high grade vesicoureteral reflux by calyceal orientation.

INTRODUCTION/OBJECTIVE: Modern radiographic advances have allowed for detailed and accurate imaging of not only urologic anatomy but also urologic function. The art of observational inference of subtle anatomic features and function from a static radiograph is being traded for new, more precise, and more expensive modalities. While the superiority of these methods cannot be denied, the total information provided in simpler tests should not be ignored. The relationship between high grade vesicoureteral reflux with the dilated calyces arranged cephalad to a dilated funnel-shaped renal pelvis on VCUG and reduced differential renal function has not been previously described, but has been anecdotally designated a "flowerpot" sign by our clinicians. We hypothesize that the appearance of a "flowerpot" kidney as described herein is an indicator of poor renal function in the setting of high grade VUR. STUDY DESIGN: IRB approval was obtained and 315 patients were identified from system-wide VCUG reports from 2004-2012 with diagnosed "high grade" or "severe" vesicoureteral reflux. Inclusion into the study required grade IV or V VUR on initial VCUG and an initial radionuclide study for determination of differential function. Patients with a solitary kidney, posterior urethral valve, multicystic dysplastic kidney, renal ectopia, or duplex collecting systems were excluded. Grade of reflux, angle of the inferior-superior calyceal axis relative to the lumbar spine, and differential uptake were recorded along with presence of the new "flowerpot" sign. Variables were analyzed using the Mann-Whitney U test to determine statistical significance. RESULTS: Fifty seven patients met inclusion criteria with 11 being designated as "flowerpot" kidneys. These "flowerpot" kidneys could be objectively differentiated from other kidneys with grade IV and/or grade V VUR both by inferior-superior calyceal axis (median angle, 52° [37-66] vs. 13° [2-37], respectively p < 0.001) and by differential renal uptake (median, 23% [5-49] vs. 45% [15-81], respectively p < 0.001). Likewise, there was no difference between either calyceal axis (median angle, 13° [3-20] vs. 13° [2-37]) or differential function (median, 48% [24-81] vs. 40% [15-66], p = 0.129) when comparing kidneys with grade IV and grade V VUR, respectively, that did not demonstrate the "flowerpot" sign. DISCUSSION/CONCLUSION: Grading of VUR is used to provide a common language for scientific discussion and determine prognosis for children with similar attributes. The dysmorphic calyceal system in the "flowerpot" kidneys supports the theory of abnormal renal blastema induction associated with abnormal differentiation of the ureteral bud. Even in the absence of urinary tract infections and/or pyelonephritis, renal abnormalities and decreased differential function can be observed on renal scintigraphy. This study also confirms the male predominance and functional similarities between grade 4 and 5 refluxing renal units. Recognizing this is a limited observational study based on imaging alone, the "flowerpot" sign is an indicator of the most severe form of grade 5 VUR but is only one factor in predicting long term overall renal prognosis. However, 14% (8/57) of our cohort had a relative uptake of less than 20% with 5 of these exhibiting the "flowerpot" sign. The "flowerpot" sign on VCUG can be used as indirect evidence of poor differential renal function and, therefore, useful in guiding parental expectations prior to formal functional imaging.

ACR appropriateness criteria post-treatment follow-up of renal cell carcinoma.

Although localized renal cell carcinoma can be effectively treated by surgery or ablative therapies, local or distant metastatic recurrence after treatment is not uncommon. Because recurrent disease can be effectively treated, patient surveillance after treatment of renal cell carcinoma is very important. Surveillance protocols are generally based on the primary tumor's size, stage, and nuclear grade at the time of resection, as well as patterns of tumor recurrence, including where and when metastases occur. Various imaging modalities may be used in the evaluation of these patients. Literature on the indications and usefulness of these radiologic studies is reviewed. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Most infants with dilating vesicoureteral reflux can be treated nonoperatively.

PURPOSE: Dilating vesicoureteral reflux provokes concern for physicians and parents that often leads to corrective surgery in young children. Since there are limited data describing the natural history of dilating vesicoureteral reflux in infants, we identified factors predictive of resolution/improvement in infants initially treated nonoperatively. MATERIALS AND METHODS: We reviewed the medical records of 90 infants 6 months old or younger from 2004 to 2010 who were referred for prenatal hydronephrosis or initial febrile urinary tract infection and found to have dilating vesicoureteral reflux (grade 3 or greater). Variables of interest included presentation, dimercapto-succinic acid results, sex, breakthrough febrile urinary tract infections, reflux grade and bilateral reflux. Cox regression analysis was performed to determine predictors of spontaneous resolution and/or improvement to reflux grade less than 3 as well as predictors of surgical intervention. RESULTS: Included in final analysis were 80 infants (113 renal units). Of the patients 51 (64%) experienced spontaneous resolution/improvement with a mean followup of 29 months before resolution, discharge home and/or end of followup. Only 20 patients (25%) underwent surgery. Cox regression analysis revealed that a normal initial dimercapto-succinic acid scan, initial reflux grade less than 5 and absent breakthrough febrile urinary tract infections were predictive of reflux resolution/improvement (p <0.05). Dimercapto-succinic acid scan abnormalities, prenatal hydronephrosis and breakthrough febrile urinary tract infections were significant predictors of surgery (p <0.05). CONCLUSIONS: Dilating vesicoureteral reflux in infancy often resolves/improves spontaneously. Therefore, surgery should be directed toward patients unlikely to experience resolution, ie those with an abnormal initial dimercapto-succinic acid scan, grade 5 vesicoureteral reflux and breakthrough febrile urinary tract infections.

Phenobarbital-enhanced hepatobiliary scintigraphy in the diagnosis of biliary atresia: two decades of experience at a tertiary center.

BACKGROUND: Hepatobiliary scintigraphy is highly sensitive for diagnosing biliary atresia; however, its specificity has varied in the literature from 35% to 97%. OBJECTIVE: The purpose of this study was to re-evaluate the accuracy of phenobarbital-enhanced hepatobiliary scintigraphy in differentiating biliary atresia from other causes of neonatal cholestasis. MATERIALS AND METHODS: We retrospectively reviewed all hepatobiliary scans of infants with cholestasis at our institution from December 1990 to May 2011. Per our routine protocol the scans were obtained after pretreatment with phenobarbital (5 mg/kg/day for 5 days) to achieve a serum level of ≥15 mcg/ml. Normal hepatic uptake with no biliary excretion by 24 h was considered consistent with biliary atresia. RESULTS: One hundred eighty-six infants with 210 hepatobiliary scans composed the study group. Forty-three (23%) infants had the final diagnosis of biliary atresia. Hepatobiliary scintigraphy was 100% sensitive, 93% specific and 94.6% accurate in diagnosing biliary atresia. Of the 186, 39/111 (35.1%) term and 2/68 (2.9%) preterm infants had biliary atresia; two of seven children with unknown gestational age also had biliary atresia. Other diagnoses included neonatal hepatitis, total parenteral nutrition cholestasis, Alagille syndrome, cystic fibrosis, choledochal cyst, hypothyroidism, alpha-1 antitrypsin deficiency and persistent cholestasis of unknown etiology. CONCLUSION: Phenobarbital-enhanced hepatobiliary scintigraphy is highly accurate in differentiating biliary atresia from other causes of neonatal cholestasis. Biliary atresia is rare in premature infants.

Two-phase whole-body skeletal scintigraphy in children--revisiting the usefulness of the early blood pool phase.

The usefulness of whole-body blood pool imaging as part of Tc-99m methylene diphosphonate (MDP) skeletal scintigraphy in detection of marrow infiltrative processes and unexpected soft-tissue and visceral abnormalities is demonstrated via illustrative case examples. Technical aspects of this simple and fast scanning technique are also highlighted.

Scintigraphic features of duplex kidneys on DMSA renal cortical scans.

The spectrum of manifestations of duplex kidneys on (99m)Tc-dimercaptosuccinic acid (DMSA) renal cortical scans and correlating findings on other imaging modalities are presented. Relevant embryology of the duplex systems and technical aspects of DMSA scintigraphy are reviewed.

Evaluation of differential renal function and renographic patterns in patients with dietl crisis.

PURPOSE: We analyzed preoperative and postoperative differential renal function and characterized the renographic findings in patients with ureteropelvic junction obstruction associated with Dietl crisis. MATERIALS AND METHODS: Patients with Dietl crisis who underwent pyeloplasty between January 2004 and December 2010 were classified by renographic presentation. Patients in group 1 were diagnosed with cortical retention, those in group 2 had an initial obstructed scan (T1/2 of 20 minutes or more and no cortical retention) and those in group 3 had an initial nondiagnostic scan (T1/2 of less than 20 minutes and no cortical retention). Renographic parameters were used to analyze each group. RESULTS: A total of 59 patients met criteria for study inclusion. The 13 patients in group 1 demonstrated the most significant recovery of function after pyeloplasty (mean differential renal function change 13.59%). The 38 patients in group 2 exhibited a mean differential renal function change of 43.06% (range 20% to 54.6%) and mean preoperative T1/2 of 64.31 minutes. Pyeloplasty was performed in all 8 patients in group 3 based on subsequent diagnostic scan (4 patients) or increased hydronephrosis on other imaging associated with further symptomatic episodes (4). Initial renographic patterns noted in group 3 included biphasic curves, diminished clearance after 15 minutes upright or symptoms despite nonobstructive drainage. CONCLUSIONS: Interpretation of diuretic renography requires the assimilation of multiple parameters since patients with Dietl crisis can exhibit variability in renographic patterns due to the intermittent nature of ureteropelvic junction obstruction. Cortical retention represents a specific and pathognomic finding of acute ureteropelvic junction obstruction. With appropriate evaluation of these parameters, obstruction can be reliably diagnosed and appropriate surgical candidates chosen.

ACR Appropriateness Criteria® acute onset flank pain--suspicion of stone disease.

Low dose (<3 mSv) noncontrast CT (NCCT) is the imaging study of choice for accurate evaluation of patients with acute onset of flank pain and suspicion of stone disease (sensitivity 97%, specificity 95%). NCCT can reliably characterize the location and size of an offending ureteral calculus, identify complications, and diagnose alternative etiologies of abdominal pain such as appendicitis. By comparison, the sensitivity of radiographs (59%) and ultrasound (24-57%) for the detection of renal and ureteral calculi is relatively poor. Ultrasound can accurately diagnose pelvicaliectasis and ureterectasis, but it may take several hours for these findings to develop. In the pregnant patient, however, ultrasound is a first line test as it does not expose the fetus to ionizing radiation. MR is an accurate test for the diagnosis of pelvicaliectasis and ureterectasis, but is less sensitive than CT for the diagnosis of renal and ureteral calculi. For patients with known stone disease whose stones are visible on radiographs, radiographs are a good tool for post-treatment follow-up.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria ® acute onset of scrotal pain--without trauma, without antecedent mass.

Men or boys, who present with acute scrotal pain without prior trauma or a known mass, most commonly suffer from torsion of the spermatic cord; epididymitis or epididymoorchitis; or torsion of the testicular appendages. Less common causes of pain include a strangulated hernia, segmental testicular infarction, or a previously undiagnosed testicular tumor. Ultrasound is the study of choice to distinguish these disorders; it has supplanted Tc-99 m scrotal scintigraphy for the diagnosis of spermatic cord torsion. MRI should be used in a problem solving role if the ultrasound examination is inconclusive. The ACR Appropriateness Criteria ® are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.