Clinical implications of primary "occult" vesicoureteral reflux in male children

OBJECTIVES

To compare characteristics and outcomes of vesicoureteral reflux (VUR) detected solely on isotopic cystography (IC) ("occult" VUR) with voiding cystourethrography (VCUG)-detected VUR.

MATERIALS AND METHODS

Between 2015 and 2020, we retrospectively enrolled all male children first undergoing VCUG and, if negative, IC in the same session. Kidney injury (KI) was defined by abnormal estimated glomerular filtration rate and/or blood pressure and/or proteinuria.

RESULTS

We enrolled 421 males with a median age of 3 months and a follow-up of 5.3 years. None exhibited KI initially, but 10% of those with VUR developed KI during follow-up. Two hundred and twenty-two patients (52.7%) did not show VUR, 152 (36.1%) had VCUG-diagnosed VUR, and 47 (11.2%) had occult VUR. Therefore, 47/199 patients (23.6%) with VUR had occult VUR. Among these, 34/47 (72.3%) had dilated VUR, and 22/47 (46.8%) exhibited split renal function < 45% and/or scar (scintigraphic damage). Compared to patients with occult VUR, those with VCUG-diagnosed VUR showed a similar prevalence of febrile urinary tract infection (fUTI) before and after VUR diagnostics and KI at the last follow-up but a higher prevalence of dilated VUR, of scintigraphic damage, and underwent surgery more frequently. At multiple logistic regression analysis, patients with VCUG-diagnosed VUR presented an increased risk of fUTI either before or after VUR diagnosis and of KI, while patients with occult VUR presented an increased risk of fUTI before (and among patients with dilated VUR also after) VUR diagnosis and of KI.

CONCLUSION

Occult VUR affects 23.6% of male children with VUR with a non-negligible risk of VUR-associated KI and fUTI. IC could select, among males with recurrent fUTIs and negative VCUG, those requiring surgery for a possible dilated occult VUR.

CLINICAL RELEVANCE STATEMENT

Vesicoureteral reflux may be overlooked in 25% of boys during VCUG, yet they are at risk of fUTIs and KI. In case of recurrent infections post-negative cystourethrography, IC could detect occult reflux, guiding surgical intervention.

Diagnostic Performance of Height-Estimated Baseline Creatinine in Diagnosing Acute Kidney Injury in Children with Type 1 Diabetes Mellitus Onset

At type 1 diabetes mellitus (T1DM) onset, acute kidney injury (AKI) is very common. To diagnose AKI, the availability of a baseline serum creatinine (bSCr) is pivotal. However, in most hospitalized children the bSCr is unknown. We aimed to test whether the bSCr estimated on the basis of height (ebSCr) could be a reliable surrogate for AKI diagnosis compared with the measured bSCr (mbSCr). As the mbSCr, we considered the creatinine measured 14 days after T1DM onset while ebSCr (mg/dL) = (k × height [cm])/120 mL/min/1.73 m2, where k = 0.55 for children and adolescent girls and k = 0.7 for adolescent boys. AKI was defined as serum creatinine values >1.5 times the baseline creatinine. Kappa statistics and the percentage of agreement in AKI classification by ebSCr−AKI versus mbSCr−AKI definition methods were calculated. Bland−Altman plots were used to show the agreement between the creatinine ratio (highest/baseline creatinine; HC/BC) calculated with mbSCr and ebSCr. The number of 163 patients with T1DM onset were included. On the basis of mbSCr, 66/163 (40.5%) presented AKI while, on the basis of ebSCr, 50/163 (30.7%) accomplished AKI definition. ebSCr showed good correlation with mbSCr using both the Spearman test (rho = 0.67; p < 0.001) and regression analysis (r = 0.68; p < 0.001). Moreover, at the Bland−Altman plots, the bias of the highest/baseline creatinine ratio calculated on the basis of the mbSCr compared to ebSCr was minimal (bias = −0.08 mg/dL; 95% limits of agreement = −0.23/0.39). AKI determined using ebSCr showed 90% agreement with AKI determined using mbSCr (kappa = 0.66; p < 0.001). Finally, we compared the area under a receiver−operating characteristic curve (AUROC) of HC/BC ratio calculated on the basis of ebSCr with AUROC of the gold standard HC/BC ratio calculated on the basis of mbSCr. As expected, the gold standard had an AUROC = 1.00 with a 95% confidence interval (CI) between 0.98 and 1.00, p < 0.001. The HC/BC ratio calculated on the basis of ebSCr also had significant AUROC (AUROC = 0.94; 95% CI: 0.90−0.97; p < 0.001). The comparison of the two ROC curves showed a p < 0.001. In conclusion, when mbSCr is unknown in patients with T1DM onset, the ebSCr calculated on the basis of height could be an alternative to orientate clinicians toward AKI diagnosis.

Renal Involvement in Children with Type 2 Diabetes Mellitus Onset: A Pilot Study

Type 2 Diabetes Mellitus (T2DM) is a main cause of chronic kidney disease (CKD) in adulthood. No studies have examined the occurrence of acute kidney injury (AKI)-that enhances the risk of later CKD-and renal tubular damage (RTD)-that can evolve to AKI-in children with onset of T2DM. We aimed to evaluate the prevalence and possible features of AKI and RTD in a prospectively enrolled population of children with onset of T2DM. We consecutively enrolled 10 children aged 12.9 ± 2.3 years with newly diagnosed T2DM. AKI was defined according to the KDIGO criteria. RTD was defined by abnormal urinary beta-2-microglobulin and/or tubular reabsorption of phosphate (TRP) <85% and/or fractional excretion of Na >2%. None of the patients developed AKI, whereas 3/10 developed RTD with high beta-2-microglobulin levels (range: 0.6-1.06 mg/L). One of these three patients also presented with reduced TRP levels (TRP = 70%). Proteinuria was observed in two out of three patients with RTD, while none of patients without RTD had proteinuria. Patients with RTD presented higher beta-2-microglobulin, acute creatinine/estimated basal creatinine ratio, and serum ketones levels compared with patients without RTD. In conclusion, in our pilot observation, we found that none of the 10 children with T2DM onset developed AKI, whereas three of them developed RTD.

Early Renal Ultrasound in Congenital Solitary Kidney May Help to Select Patients at Lower Risk of Associated Vesicoureteral Reflux

BACKGROUND

Vesicoureteral reflux (VUR) may be associated with renal dysplasia and reduced renal length (RL). The diagnosis of VUR in children with congenital solitary functioning kidney (CSFK) identifies patients at risk of kidney injury but exposes to invasive procedures.

OBJECTIVE

We aimed to test the hypothesis that an RL >2 standard deviation score (SDS) in the first months of life - reflecting renal hyperplasia - could identify CSFK patients with lower probability of presenting VUR.

METHOD

We retrospectively selected 207 CSFK patients with prenatal diagnosis of CSFK and having undergone renal ultrasound (RUS) both at 0-3 and 10-13 months of life, renal scintigraphy, and cystourethrography/cysto-scintigraphy. We compared the cumulative proportion of an RL >2 SDS by Kaplan-Meier analysis and evaluated the odds to present VUR of patients with an RL >2 SDS both at the first and second RUS.

RESULTS

Overall, 3.3% of patients with VUR and 22.0% of patients without VUR presented an RL >2 SDS at the first RUS (p = 0.02). At the second RUS, 53.3% of patients with VUR and 52.5% of patients without VUR presented an RL >2 SDS (p = 0.93). Patients without VUR presented higher cumulative proportion of an RL >2 SDS at 3 months of life than those with VUR (p = 0.02). This difference however disappeared at 11 and 13 months of age (p = 0.17 and p = 0.54, respectively). An RL >2 SDS within 3 months of life presented an OR for VUR of 0.12 (95% CI: 0.02-0.92; p = 0.005), while an RL >2 SDS at 12 months of life presented an OR for VUR of 0.96 (95% CI: 0.45-2.1; p = 0.93).

CONCLUSION

Only an RUS made in the first months of life could identify CSFK patients at lower risk of presenting an associated VUR.

DTI parameters in neonates with hypoxic-ischemic encephalopathy after total body hypothermia

BACKGROUND AND PURPOSE

MR imaging provides means for discriminating different patterns of Hypoxic-ischemic encephalopathy (HIE) and may distinguish most severe cases from less severe but is unable to predict long-term outcome. Diffusion tensor imaging (DTI) offers information for a more complete characterization of HIE. The purpose of this study is to compare the modifications of DTI parameters in newborns one week and six months following total-body cooling to healthy controls.

METHODS

Forty-seven cooled newborns were studied with MRI, 20 underwent follow-up at 6 months. 12 healthy newborns and nine children at 6 months were enrolled as control groups (HC). Inferior Longitudinal Fasciculus (ILF), Corpus Callosum Fasciculus (CCF), Corticospinal Tract (CST), Optical Tract (OT), Optic Radiation (OR) were generated in all subjects. DTI parameters were evaluated in basal ganglia (BG), thalamus (TH) and tracks. Statistical analysis was performed with MANOVA.

RESULTS

In newborns HIE versus HC, there were significantly lower fractional anisotropy (FA) on OR and CST and higher axial diffusivity (AD), apparent diffusion coefficient (ADC) and radial diffusivity (RD) values on CST, BG and TH in HIE-N. At 6 months there were no significant grouping effects. The analysis showed a significant increase of FA, decrease of ADC, AD, RD after 6 months for HIE and HC.

CONCLUSIONS

We observed modifications of parameter values in HIE newborns vs HC; however normalization of values at 6 months suggests that changes of parameters cannot be considered early biomarkers for evaluation of therapeutic hypothermia in newborns with moderate HIE and normal conventional MRI.

Hematuria at dipstick on first versus second morning voiding: A screening for patients with persistent isolated hematuria?

BACKGROUND

In our clinical practice we observed that -differently from patients with defined glomerulopathies- children with persistent isolated microscopic hematuria (PImH) usually shows at dipstick on first compared with second morning voiding lower degree of hematuria. We hypothesized that comparison of hematuria degree between first and second morning voiding (dipstick comparison test) could help in selection of patients needing of specific investigations. In this study, we aimed preliminarily validating our hypothesis.

METHODS

To define the risk of active glomerulopathies we used patients with defined glomerulopathies as cases. We prospectively enrolled 103 children during a one-year period. Sixty-nine of them had PImH, 16 microscopic/macroscopic hematuria (mMH), and 18 defined glomerulopathies. Inclusion criteria were: 1) persistent microscopic hematuria (≥1+ at dipstick) with or without defined glomerulopathy and/or previous episodes of macroscopic hematuria; 2) for the patients without defined glomerulopathy, having made regular biannual follow-up visits for at least 2 years in our department; 3) normal renal function and blood pressure at enrollment visit. We compared hematuria degree between first and second morning voiding. Possible findings were absence (NH), less degree (LH), similar degree (SH), and higher degree (HH) of hematuria in the first compared with second voiding.

RESULTS

At dipstick comparison test, 27.2% of patients presented NH, 44.7% LH, 28.1% SH, and none HH. NH showed specificity and PPV of 100% and significant area under receiver operating characteristic curve (AUROC = 0.66; 95%CI:0.55-0.78; p = 0.03) for absence of defined glomerulopathies. LH showed better sensitivity (76.9% Vs 33%) and NPV (78.9% Vs 24%) and lower specificity (88.2% Vs 100%) and PPV (87.0% Vs 100%) than NH for absence of defined glomerulopathies. Moreover, the LH showed a non-significant AUROC curve for presence of defined glomerulopathies. SH showed specificity of 80%, NPV of 91.9% and significant AUROC curve for presence of defined glomerulopathies (0.67; 95%CI:0.55-0.80; p = 0.009). The ROC curve analysis examining the delta of hematuria degree comparing first with second morning urine voiding showed a significant AUROC curve (AUROC = 0.78; 95%CI,0.68-0.89; p = 0.0002) with delta ≤ 1 showing the best sensitivity (80%) and specificity (66.7%) for defined glomerulopathies. None of the patients with defined glomerulopathies presented NH. Having SH presented relative risk for defined glomerulopathy of 5.1 (95%CI:1.9-13.6; p = 0.0007). Conversely, taken together NH and LH the RR was 0.2 (95%CI 0.1-0.5; p = 0.0007).

INTERPRETATIONS

The dipstick on the first urine voiding underestimates the hematuria in about 70% of patients. The dipstick comparison test might easily screen patients with PImH and mMH needing of further investigations and treatment.

Functional neuroimaging in anorexia nervosa: A clinical approach

Aims

To provide a review of the available literature about the functional neuroimaging of anorexia nervosa, and to summarize the possible role of neurobiological factors in its pathogenesis.

Methods

A systematic review of the literature was performed using PubMed and Medline electronic database (1950–September 2009). Eligible studies were restricted to those involving the main parameters of cerebral activity and functional neuroimaging techniques. Findings of the reviewed studies have been grouped on a diagnostic subtype basis, and their comparison has been interpreted in terms of concordance.

Results

We found a high level of concordance among available studies with regard to the presence of frontal, parietal and cingulate functional disturbances in both anorexia nervosa restricting and binge/purging subtypes. Concordance among studies conducted regardless of the anorexia nervosa subtypes suggests an alteration in temporal and parietal functions and striatal metabolism.

Conclusions

The most consistent alterations in anorexia nervosa cerebral activity seem to involve the dorsolateral prefrontal cortex, the inferior parietal lobule, the anterior cingulate cortex and the caudate nucleus. They may affect different neural systems such as the frontal visual system, the attention network, the arousal and emotional processing systems, the reward processing network, and the network for the body schema.

'Frequently recurring' nocturnal polyuria is predictive of response to desmopressin in monosymptomatic nocturnal enuresis in childhood

INTRODUCTION

The nocturnal polyuria is considered a significant predictive value for response to desmopressin. The cutoff value useful to define nocturnal polyuria is still a matter of debate. Moreover, it is current notion that maximal voided volume (MVV) could be used as a predictor for desmopressin response.

OBJECTIVE

The objective of this study was to assess the impact of different definitions of nocturnal polyuria (and of its frequency) and MVV in predicting the response to desmopressin.

STUDY DESIGN

A total of 103 patients with frequent monosymptomatic nocturnal enuresis (≥4 wet nights/week) were enrolled. A bladder diary over a 4-day period was collected. The MVV was defined as the highest micturition volume detected at bladder diary. Nocturnal diuresis was measured in 5 wet nights. Then, patients were administered with 120 mcg of sublingual desmopressin. After 2 months, if there was no complete response, the dose was increased to 240 mcg. Nocturnal polyuria was defined as follows: 1.Definition 1: nocturnal urine production >130% of the expected bladder capacity (EBC). 2. Definition 2: >100% EBC. 3. Definition 3: > 20×(age + 9) mL. The primary outcome was 'response to desmopressin' after 3 months of treatment.

RESULTS

Fifty-three patients responded to desmopressin. Comparing the responses to desmopressin on the basis of the three definitions of nocturnal polyuria, no significant difference was found. There was no cutoff value of nocturnal polyuria expressed as %EBC useful in providing a significant receiver-operating characteristic (ROC) curve. The area under the ROC curve for MVV expressed as %EBC was 0.67 (95% confidence interval [CI], 0.54-0.80; p = 0.01). A MVV >103.1% of EBC had 78.8% (95% CI, 61.1-91.0) sensitivity and 47.5% (95% CI, 31.5-63.9) specificity for predicting response to desmopressin. Among the patients with nocturnal polyuria according to definition 1, a higher percentage of subjects with nocturnal polyuria in 4 out of 5 or 5 out of 5 nights responded to desmopressin, compared with other patients. Patients presenting with nocturnal polyuria according to definition 3 in 5 out of 5 nights showed a 100% of response to desmopressin. At multivariate analysis, the only significant odds ratio (OR) to respond to desmopressin was that of patients with nocturnal polyuria according to definition 1 in >3 nights (OR = 7.1, 95% CI, 1.3-40.3).

DISCUSSION AND CONCLUSIONS

The presence or absence of nocturnal polyuria-according to all three definitions-in at least one night was not effective in predicting the response to desmopressin. Predictors of desmopressin response were nocturnal polyuria in >3 out of 5 wet nights according to definition 1 and in 5 out of 5 wet nights according to definition 3.

Congenital solitary kidney size at birth could predict reduced eGFR levels later in life

OBJECTIVES

To evaluate the impact of congenital solitary functioning kidney (CSFK) length, measured early in life, on the eGFR levels during the follow-up.

STUDY DESIGN

We retrospectively selected 162 CSFK patients undergoing, within 60 days of life, renal length (RL) measurement by ultrasound. We divided the population in: Group 1 = RL ≥ 2 standard deviation score (SDS). Group 2 = RL < 2 SDS and showing RL ≥ 2 SDS during the follow-up. Group 3 = RL < 2 SDS and showing RL < 2 SDS during the follow-up.

PRIMARY OUTCOME

development of eGFR below the range of normality.

RESULTS

The median follow-up period of the overall population was 6.2 years (range 2-21.5 years). The cumulative proportion of patients free of primary outcome at 15 years of age was 96.4% in group 1, 64.6% in group 2, and 45.6% in group 3 (p = 0.03). The RL > 2 SDS within 60 days of life was a significant protective factor (hazard ratio = 0.13; 95% C.I. 0.02-0.97) against development of primary outcome.

CONCLUSION

RL ≥ 2 SDS within 60 days of life could identify a population of CSFK with reduced risk of presenting reduced eGFR levels later in life.

Extraordinary daytime only urinary frequency in childhood: Prevalence, diagnosis, and management

INTRODUCTION

Since standardization of the ICCS terminology, only two small case series of children with extraordinary daytime only urinary frequency (EDOUF) have been published. The aims of the present study were i) to describe a large cohort of children affected by EDOUF, to evaluate its rate among the main micturition pediatric disturbances, and to determine if there is different EDOUF onset among seasons; ii) to investigate possible associations with urodynamic abnormalities by non-invasive techniques; iii) to evaluate whether postponing micturition exercise (PME) can objectively verify the anamnestic data hinting at the EDOUF diagnosis; and iv) to determine the effect of postponing micturition at home.

MATERIAL AND METHODS

We reviewed the records of all patients with EDOUF, nocturnal enuresis, and/or overactive bladder firstly examined from March 2012 to February 2016. We evaluated post-void residual and bladder wall thickness by urinary ultrasound and uroflowmetry and recorded the season in which the EDOUF started. Through the PME, the EDOUF diagnosis was confirmed if patients were able to postpone micturition reaching at least 80% of the expected bladder capacity without showing urinary incontinence. At home, we recommended postponing micturition for a maximum of 3 h if EDOUF affected the normal daily activities of both children and parents. We set a telephone interview for 3 months later.

RESULTS

The clinical characteristics of the EDOUF population are shown in the Table. The EDOUF rate was 12.1%. The rate of EDOUF onset was significantly lower during the summer than in other seasons (p = 0.02) and the OR for onset of EDOUF in the summer - compared with the other seasons - was 0.37 (95% CI 0.18-0.74; p = 0.005). Eighty-five (80.2%) patients reported an intermittent trend of the EDOUF with variable periods of improvement and worsening. All the EDOUF patients had normal uroflowmetry, 1/106 had post-micturition bladder wall thickness >5 mm and one post-void residual. At the PME, 106 out of 106 (100%) patients with EDOUF were able to reach at least 80% of the EBC without showing urinary incontinence or urgency incontinence. After 3 months, in 98.1% of the patients the symptoms had disappeared or improved.

DISCUSSION AND CONCLUSIONS

Childhood EDOUF is rather common and is generally associated with normal non-invasive urodynamic patterns. The PME allows verification of anamnestic data of EDOUF. The sole recommendation to postpone micturition for a maximum of 3 h or until the micturition postponement became stressful could be considered as a possible approach.

Anthropometric and Biochemical Determinants of Estimated Glomerular Filtration Rate in a Large Cohort of Obese Children

OBJECTIVE

We aimed to investigate which clinical and metabolic factors could influence the estimated glomerular filtration rate (eGFR) levels, evaluating a large population of obese children without suspect of primary kidney disease.

DESIGN

Retrospective, cross-sectional study.

SETTING

Pediatric university department.

SUBJECTS

We enrolled 2,957 obese children and adolescents consecutively attending our department between January 2000 and 2017. Inclusion criteria were body mass index (BMI) > 95th percentile and eGFR > 90 mL/min/1.73 m². Exclusion criteria were secondary forms of obesity, eGFR < 90 mL/min/1.73 m², proteinuria/hematuria at urine dipstick, or consumption of any medication.

INTERVENTIONS

Weight, waist circumference, height, waist to height ratio (W/Hr), BMI-standard deviation score (SDS), pubertal stage, systolic blood pressure (SBP) and diastolic blood pressure (DBP), duration of obesity, insulin, eGFR, and homeostasis model assessment (HOMA-IR) were obtained. A general linear model was performed for a multiple variable analysis.

MAIN OUTCOME MEASURE

The population was divided in tertiles for BMI-SDS, W/Hr, SBP- and DBP-SDS, HOMA-IR, and duration of obesity. We compared eGFR levels among these tertiles.

RESULTS

The eGFR levels significantly increased across both BMI-SDS and W/Hr tertiles. Conversely the eGFR levels significantly decreased across SBP-SDS, HOMA-IR, and duration of obesity tertiles. No significant differences in eGFR levels across DBP-SDS tertiles were detected. Pubertal patients presented significantly lower eGFR values compared with prepubertal patients. A general linear model for eGFR variance including as covariates W/Hr, HOMA-IR, duration of obesity, pubertal stage, BMI-SDS, and SBP-SDS (model R² 39.7%; model P < .00001) was performed. It confirmed a direct association of eGFR values with BMI-SDS and an indirect association with HOMA-IR, duration of obesity, pubertal stage, and SBP-SDS.

CONCLUSIONS

We showed a positive correlation of eGFR with both BMI-SDS and a negative one with SBP-SDS, HOMA-IR, pubertal stage, and duration of obesity. The duration of obesity was the variable most significantly associated to eGFR levels.

From oliguria to urinary incontinence: a case of Munchausen's syndrome in an adolescent boy

Factitious disorders are characterized by physical or psychological symptoms that are intentionally produced or feigned in order to assume the sick role. "Munchausen's syndrome" is one of these disorders and often is under-recognized or only suspected after unnecessary investigations. We report the case of a 15-year-old boy who came to our notice because of reduced urine output and recurrent abdominal pain during the previous 3 months. The patient attended several emergency room visits and he had been hospitalized for 1 month in an adult internal medicine department because of "oliguria". He had undergone several invasive investigations with normal results before the diagnosis of Munchausen's syndrome was made. General pediatricians and practitioners should be aware that suspecting Munchausen's syndrome in the first instance in the management of a patient showing discrepancies between reported urinary symptoms and the detectable clinical signs could avoid unnecessary and invasive exams.

Albumin: physiologic and clinical effects on lung function

Fluid resuscitation is one of the most frequent and necessary practices in clinical medicine and is an integral part of the initial stabilization of critically ill, hypovolemic patients. Longstanding debate and conflicting evidence surround the use of both colloid and crystalloid fluid resuscitation in these patients. The basis of this debate is heavily rooted in the physiological understanding of Starling's forces. In this review, we aim to highlight the ongoing debate of albumin versus crystalloid resuscitation both broadly and as it relates to lung function, and will discuss the current state-of-the-art, starting from an historic perspective and progressing through a review of both physiologic and clinical evidence. Despite the biologic and physiologic plausibility of therapeutic benefit, the current evidence base does not support the routine use of albumin administration to improve patient survival or prevent respiratory dysfunction.

[Urolithiasis in children: diagnostic difficulties]

The incidence of urolithiasis in children has been steadily increasing in developed countries mainly due to changes in dietary habits. The occurrence of symptoms suggestive of urolithiasis in children with urinary solute abnormalities predisposing to stone formation but with normal renal ultrasound and X-ray plain film is approximately 9 times higher than the occurrence of overt stone disease. This discrepancy may depend on several factors, for example: the limited sensitivity of these methods of imaging, the presence of urinary crystals that, while not detectable with imaging, injure bladder epithelium, in addition to imaging studies performed after the passage of calculi giving negative results. Correct technique during urine collection is also essential for diagnosis. Urolithiasis must be suspected in the face of abdominal pain even central or diffuse pain in younger children when there is a positive family history even though specific urinary symptoms such hematuria and dysuria may be lacking.

Alternative normalization methods demonstrate widespread cortical hypometabolism in untreated de novo Parkinson's disease

AIM

Previous positron emission tomography (PET) [18F]fluorodeoxyglucose ([18F]FDG) studies in Parkinson's disease (PD) demonstrated that moderate to late stage patients display widespread cortical hypometabolism, whereas early stage PD patients exhibit little or no cortical changes. However, recent studies suggested that conventional data normalization procedures may not always be valid, and demonstrated that alternative normalization strategies better allow detection of low magnitude changes. We hypothesized that these alternative normalization procedures would disclose more widespread metabolic alterations in de novo PD.

METHODS

[18F]FDG PET scans of 26 untreated de novo PD patients (Hoehn & Yahr stage I-II) and 21 age-matched controls were compared using voxel-based analysis. Normalization was performed using gray matter (GM), white matter (WM) reference regions and Yakushev normalization.

RESULTS

Compared to GM normalization, WM and Yakushev normalization procedures disclosed much larger cortical regions of relative hypometabolism in the PD group with extensive involvement of frontal and parieto-temporal-occipital cortices, and several subcortical structures. Furthermore, in the WM and Yakushev normalized analyses, stage II patients displayed more prominent cortical hypometabolism than did stage I patients.

CONCLUSION

The use of alternative normalization procedures, other than GM, suggests that much more extensive cortical hypometabolism is present in untreated de novo PD patients than hitherto reported. The finding may have implications for our understanding of the basic pathophysiology of early-stage PD.

Recurrent abdominal pain in childhood urolithiasis

OBJECTIVE

Our goal was to establish the clinical presentation and features of pain attacks in children with recurrent abdominal pain (RAP) and urolithiasis.

METHODS

We compared the rate of previous appendectomy among 100 consecutive patients with that of 270 control subjects. We also compared the frequency of pain attacks with that reported by children with functional or organic gastrointestinal RAP.

RESULTS

Fifty-three patients had no history of dysuria or gross hematuria, and only 35 had hematuria at the first visit; 41 patients were evaluated for urolithiasis only because of a family history of kidney stones associated with RAP. Twenty-nine patients had been previously hospitalized for abdominal symptoms. Sixteen patients and 4 control subjects (1.5%) had undergone a previous appendectomy (P < .0001). Two to 28 months before the diagnosis of urolithiasis, 37 patients underwent abdominal ultrasonography, which did not show urinary stones. Sixty-nine percent of subjects younger than 8 years of age had central/diffuse abdominal pain. The mean frequency of pain attacks was 4 to 9 times lower than in patients with functional or organic gastrointestinal RAP.

CONCLUSIONS

Because of the inconstant occurrence of dysuria and hematuria, the location of pain in areas other than the flank, and the lack of calculi shown on imaging studies performed after pain attacks, the urologic origin of pain may be overlooked and ineffective procedures performed. The possibility of urolithiasis should be considered in children with RAP who have a family history of urolithiasis and/or infrequent pain attacks, even when dysuria and hematuria are lacking, and in younger children even when pain is not lateral.

Differing urinary urea excretion among children with idiopathic hypercalciuria and/or hyperuricosuria

OBJECTIVE

To estimate dietary protein intake in children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU).

PATIENTS AND METHODS

We compared the 24-h urinary excretion of urea, as a reflection of protein intake, in four age- and sex-matched groups, each comprising 56 consecutive children: (1) HC, (2) HU, (3) HC+HU and (4) control.

RESULTS

Urinary urea excretion was significantly higher in HC, HU and HC+HU than in controls. HC and HU children had similar urea excretion. HC+HU children had urinary urea significantly higher than HC and HU, but urinary calcium similar to HC and urinary uric acid excretion similar to HU subjects. Urinary calcium was significantly (R(2)=0.21) correlated with urea excretion in HC children only, whereas urinary uric acid was significantly (R(2)=0.21) correlated with urinary urea in HU children only. No significant correlation between urinary urea and calcium or uric acid excretion was found in HC+HU patients although they had the highest urinary urea. A significant (p=0.004) interaction between urinary urea and sodium in increasing urinary calcium excretion resulted only in the HC group.

CONCLUSION

The association of dietary protein excess with HC and/or HU is conditioned by an individual (genetic?) predisposition and may be produced by different mechanisms.

ROBO2 gene variants are associated with familial vesicoureteral reflux

The SLIT2 receptor ROBO2 plays a key role in the formation of the ureteric bud, and its inactivation in mice leads to supernumerary ureteric bud development, lack of ureter remodeling, and improper insertion of the ureters into the bladder. Recently, two heterozygous ROBO2 missense mutations were identified in two families with primary vesicoureteral reflux occurring in combination with congenital anomalies of the kidney and urinary tract (VUR/CAKUT). This study investigated a possible causal role of ROBO2 gene variants in 95 unrelated patients with primary VUR (n = 78) or VUR/CAKUT. Eighty-two percent of all patients had a family history of genitourinary anomalies. Twenty-four ROBO2 gene variants were identified by direct sequencing of all 26 exons and the exon-intron boundaries. Of these, four led to amino acid substitutions: Gly328Ser, Asn515Ile, Asp766Gly, and Arg797Gln. When the families were examined, the missense variants co-segregated with VUR (three families) or VUR/CAKUT (one family). These variants were not found in 190 control subjects, and the affected amino acids have been conserved through evolution. In conclusion, a relatively high frequency of ROBO2 variants (5.1%) was found in familial cases; however, functional studies and validation in other cohorts are warranted.

Long-term evolution of renal damage associated with unilateral vesicoureteral reflux

PURPOSE

We determined the long-term evolution of renal damage associated with vesicoureteral reflux.

MATERIALS AND METHODS

We retrospectively selected 74 consecutive children with unilateral primary vesicoureteral reflux, ipsilateral renal differential uptake less than 45% at dimercapto-succinic acid scintigraphy performed 4 to 6 months after urinary tract infection (60 patients) or shortly after diagnosis of vesicoureteral reflux investigated for prenatal hydronephrosis (14), and normal ultrasound and scintigraphic imaging of the contralateral nonrefluxing kidney. Average patient age at diagnosis was 3 years. The outcome was assessed via dimercapto-succinic acid scan at 5 to 24 years (mean 8.9).

RESULTS

In 65 patients (88%) variations of less than 5% in differential uptake were recorded. Three patients (4%) showed an increase of greater than 5% in differential uptake of the refluxing kidney. Six patients (8%) demonstrated a decrease of greater than 5%, of whom 3 had 1 and 3 had no febrile urinary tract infection during followup. A total of 18 patients had a differential uptake of 35% to 45% at the first visit, of whom 3 exhibited a decrease of 5.2% to 27% in differential uptake and had no history of febrile urinary tract infection.

CONCLUSIONS

In most cases differential uptake of the unilaterally refluxing affected kidney remains stable from early childhood to puberty despite the increase in body mass, which necessitates increasing renal work. In some patients a significant decrease in differential uptake may be observed even in the absence of recurrent febrile urinary tract infections. A mild decrease in differential uptake (35% to 45%) at diagnosis does not exclude the possibility of a subsequent significant decrease, even in the absence of febrile urinary tract infection.

Urinary urea excretion in idiopathic hypercalciuria of children

OBJECTIVE

In adults, it is well known that high protein intake may increase the risk of nephrolithiasis through increased urinary calcium excretion and other mechanisms. We aimed to assess the role of protein intake on urinary calcium excretion in children with idiopathic hypercalciuria (HC).

PATIENTS AND METHODS

The 24-h urinary urea excretion as a reflection of protein intake was evaluated in 65 children with HC and in 76 normocalciuric control children. All of them were on a free diet and did not receive any specific drug.

RESULTS

Urinary urea excretion was 18.9+/-6.6 (SD) mmol/kg/day in the HC group and 14.2+/-4.9 in controls (P<0.0001). Urinary urea excretion significantly decreased with age, as well as with body weight and height gain in both groups. Calcium excretion significantly increased with increasing sodium and urea excretion in the HC but not the control group. There was a significant (P=0.005) interaction between urinary sodium and urea excretion in the rising calciuria of the HC group. Multiple regression analysis showed that, in the HC group, variations in urinary urea explained 11.4% of the entire variability of urinary calcium excretion, whereas adding the urinary sodium effect increased this relation only to 16%.

CONCLUSION

Children with HC have a higher dietary protein intake than normocalciuric children. The decrease in urea excretion with increasing age and body mass may reflect the relatively higher protein intake of young growing individuals. Salt and protein have a cumulative effect on rising calcium excretion in HC children, but the role of protein intake is outstanding.

A new Minos vector for eye-specific expression of white+ marker in Ceratitis capitata and in distantly related dipteran species

The genetic transformation of insects by transposable elements is based on the use of selectable genetic markers required to identify transgenic individuals. Conserved regulatory sequences can be used to develop single constructs capable of adequate expression of a marker, across a range of different species. We present evidence that the Drosophila GBS regulatory element (Glass-binding site), derived from the Rh1 rhodopsin gene, is able to drive in vivo eye-specific expression of a Ccwhite+ transgene in the Mediterranean fruitfly Ceratitis capitata. The Ceratitis lineage diverged from that of Drosophila approximately 120 Myr ago. As the GBS regulatory sequence seems to be partially conserved in the more distantly related dipteran species Anopheles gambiae (250 Myr), we propose that the GBS may be widely useful for driving eye-specific expression in a wide range of dipteran species.

Permanent renal parenchymal defects after febrile UTI are closely associated with vesicoureteric reflux

The finding of scintigraphic renal defects in children with febrile urinary tract infection (UTI) even in the absence of vesicoureteric reflux (VUR) has led to the conclusion that VUR is a weak predictor of renal defects in these patients. We used isotopic cystography (IC) for diagnosis of VUR in children with febrile UTI. Dimercaptosuccinic acid renal scintigraphy was performed 6 months after cure of the last UTI. Renal defects were defined by the finding of focal defects of radionuclide uptake and/or by a split renal function <43%. The study included 206 children with primary VUR and 77 without VUR. Among the subjects with and without VUR, respectively, renal defects were found in 40 and 6% (p=0.0001), focal uptake defects in 33 and 5% (p=0.0001) and split renal function <43% in 26 and 5% (p=0.0001). Permanent renal defects in children with febrile UTI are closely associated with VUR. The possibility that a child will have permanent renal defects can reasonably be ruled out on the basis of the absence of VUR by IC.

Central/diffuse abdominal perception of urological pain in children

AIM

In children with recurrent abdominal pain (RAP), the location of pain to the flank may suggest the involvement of the urinary apparatus. We aimed to evaluate the location of pain in different age groups of children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAP.

METHODS

Location of pain was assessed in 180 consecutive HC/HU children with RAP, aged 3-17.6 y, presenting to a single centre.

RESULTS

Considering four age groups, central/diffuse was more prevalent than lateral location of pain in youngsters, with a progressive and significant (p<0.0001, chi2 test for trend) decrease of the prevalence of central/diffuse location with rising age, and with the most relevant drop after age 8 y. Location of pain was central/diffuse in 81% of patients under and lateral in 79% of those over 8 y of age (p<0.0001). The location of pain changed from central/diffuse to lateral in 16/18 children followed at least 1 y, within 1 to 2 y by age 8.

CONCLUSION

Only after 8 y of age did the lateral location of abdominal pain become the rule in children with HC/HU and RAP. This has to be kept in mind in order to avoid overlooking the urologic origin of pain.

Appendectomy in children with hypercalciuria/hyperuricosuria

Recurrent abdominal pains (RAPs) represent a common problem in children sometimes leading to unnecessary and invasive procedures. The rates of appendectomy were evaluated consecutively in 180 children with idiopathic hypercalciuria (HC) and/or hyperuricosuria (HU) and RAPs, and in 270 control subjects. Of the HC/HU patients 10% and of controls 1.5% underwent appendectomy (p<0.0001). In 15 out of 18 HC/HU patients appendectomized, RAPs persisted with the same frequency and severity after the operation; 10 out of 18 had dysuria and/or gross hematuria 2 days-12 months after appendectomy. At our first visit, urinalysis was negative for hematuria in 13 out of 18 patients and in eight out of the 10 with a previous history of dysuria or gross hematuria. Pain recurrences resolved or improved in nine out of the 11 patients followed at least 1 year after general or specific therapy for HC/HU. The inconstant association of dysuria and hematuria with RAPs in children with HC/HU may lead to the urological origin of pain being overlooked, and may explain the high rate of appendectomy among these children. The possibility of HC/HU therefore should be taken into account in children with RAPs even when dysuria and hematuria are not present.

Sport hematuria in boys: a provocative test

Sports hematuria has been described in adult athletes. We report on two boys with gross hematuria after soccer matches. Urinalysis was negative for hematuria at the first visit. A simple test of effort provoked the phenomenon and allowed the detection of the post-renal origin of bleeding and the rapid resolution of hematuria. Such a test may be particularly helpful after the first episode, when it is problematic to postulate a cause-effect relationship between exercise and hematuria on the basis of the patients' history.

Growth and bone mineral density in long-lasting idiopathic hypercalciuria

Growth retardation and osteopenia have been reported in some children with idiopathic hypercalciuria (IHC), particularly in those with nephrocalcinosis. The duration of hypercalciuria might be a risk factor for osteopenia. A retrospective longitudinal analysis of statural growth and a cross-sectional evaluation of bone mineral density (BMD) was carried out in 26 IHC children followed for 4-13 years. None of the patients had nephrocalcinosis. Growth, including pubertal growth spurt, was normal in all subjects. BMD Z score less than -1 was recorded in 3 subjects with hyperuricosuria. BMD Z score averaged -0.68+/-0.99 in the 9 subjects with associated hyperuricosuria and 0.21+/-0.64 in the 17 with occasional or no hyperuricosuria ( P=0.018). Our analysis shows that children with long-lasting IHC without nephrocalcinosis have normal growth, but those with associated hyperuricosuria may be at risk for osteopenia.

[Detection of left ventricular endocardial border with tissue harmonic imaging]

BACKGROUND

Ultrasonic wave propagation in human tissues is not linear. As a consequence, harmonic waves, whose frequency is a multiple (harmonic) of the emitted frequency, are generated. Tissue Harmonic Imaging (THI) processes only the second harmonic frequency in order to improve the signal-to-noise ratio of the received signal. The study was aimed at investigating the impact of THI on the detection of the Left Ventricular (LV) endocardial border. Attention was paid to determine which LV walls were analysed more clearly with THI rather than with conventional Fundamental Frequency Imaging (FFI).

METHODS

We compared the FFI and the THI visualization of the 16 LV segments and of the 6 LV walls in 30 consecutive patients by scoring the images as bad, sufficient or good. The equipment used was a GE Vingmed System Five (Orten, Norway).

RESULTS

Images were good in 85% of segments explored with THI, whereas FFI provided good images in 47% of segments (p<0.001). From the apical window, visualization of the apex, lateral wall and anterior wall significantly improved with THI; using the parasternal approach, imaging of posterior wall was definitely better with THI than with FFI.

CONCLUSIONS

THI enhances both endocardial visualization and global image quality. Tech-nical development, however, increases the diagnostic possibilities of echocardiography but does not substitute the operator's experience.

Urinary sodium and potassium excretion in idiopathic hypercalciuria of children

BACKGROUND

An increased spot urine Na/K ratio (UNa/K) has been found to be related to urinary stone disease in adults with a history of nephrolithiasis and in children with idiopathic hypercalciuria (HC). However, the respective role played by Na and K excretion in the rise of the UNa/K in growing individuals is not well clarified.

METHODS

The urinary excretion of Na and K was evaluated in fasting morning and 24-hour urine samples of 37 consecutive children with HC and of 21 previously HC children who were normocalciuric at the time of the study (ExHC). None of them had received any dietary or specific drug prescription.

RESULTS

In the HC and in the ExHC group, respectively, the Na excretion was 4 +/- (SD) 2.4 and 2.9 +/- 1.3 mmol/kg/day (p = 0.009); the K excretion was 1.1 +/- 0.4 and 1.2 +/- 0.7 mmol/kg/day (p = 0.86); the fasting UNa/K was 3 +/- 1.6 and 2.1 +/- 1 mmol/mmol (p = 0.044), and the 24-hour UNa/K was 4.2 +/- 3.9 and 2.8 +/- 1.5 mmol/ mmol (p = 0.045). The 24-hour UNa/K was significantly higher than the fasting UNa/K in both HC (p = 0.002) and ExHC (p = 0.002) subjects. The 24-hour UNa/K significantly increased with age in both HC (p = 0.02) and ExHC (p = 0.015) children. The K excretion significantly decreased with age in HC (p = 0.0001) and ExHC (p = 0.005) subjects, as well as with body weight gain in HC (p = 0.005) and ExHC (p = 0.0001) children and with increasing body height in HC (p = 0.006) and ExHC (p = 0.001) subjects. In neither group was the K excretion significantly related to body mass index Z score nor to height Z score. No significant relation resulted between Na excretion and age, body weight and height, and body mass index Z score and height Z score.

CONCLUSIONS

HC children have a higher Na excretion as well as a higher fasting and 24-hour UNa/K than ExHC children, but no different K excretion. Meals are accompanied by a significant rise in UNa/K. The rise in UNa/K with age is mostly due to a decrease in K excretion which possibly depends on childhood body growth.

Unilateral vesicoureteric reflux: Low prevalence of contralateral renal damage

OBJECTIVE

We assessed the risk for the occurrence of renal damage in children with vesicoureteric reflux (VUR).

STUDY DESIGN

We reviewed the records of 187 consecutive children, aged 3.8 +/- (SD) 2.8 years, with unilateral primary VUR diagnosed after urinary tract infection (UTI). Dimercaptosuccinic acid renal scintigraphy was performed 4 to 6 months after the last UTI. Three patterns of renal damage were identified: global reduction (GR) of renal radionuclide uptake (20% to 40% of relative uptake), focal defects (FD) in uptake, and shrunken (relative uptake <20%) kidney (SK). We assumed that in these subjects FD indicated postpyelonephritic damage and that GR indicated congenital renal damage.

RESULTS

Scintigraphic renal damage of any type was present in 36.9% of the refluxing and in 3.2% of the nonrefluxing kidneys (odds ratio [OR], 17.6; 95% CI, 7.4 to 41.9). FD were present in 15.5% and 2.7% (OR, 6.7; CI, 2.5-17.6), GR in 19% and 0.5% (OR, 44.3; CI, 6.1 to 327.2), and SK in 6.9% and 0%, respectively. Patients with severe VUR showed a higher probability of renal damage than those with nonsevere VUR.

CONCLUSIONS

In children with UTI and VUR, the refluxing kidney is most at risk of both congenital and acquired renal damage, and this risk increases with severity of reflux.

Hyperuricosuria in children: clinical presentation and natural history

OBJECTIVE

Idiopathic hyperuricosuria (HU) was previously reported in only a limited number of children with hematuria. We aimed to outline the clinical presentation and natural history of HU not only in children with hematuria, but also in those with dysuria and/or recurrent abdominal/flank pain and a family history of urolithiasis.

STUDY DESIGN

Retrospective analysis of data at diagnosis from 102 consecutive children with HU and outcome analysis of 26 of them who were followed >/=1 years (mean: 3.1) with no specific therapy.

RESULTS

Sixty-one participants had HU and 41 had HU + hypercalciuria. Fifty-two patients had no hematuria among the presenting symptoms, more than one third had normal urinalysis at our first examination, one half had microcalculi (<3 mm in diameter) at renal sonography, and 12% had stones (4-18 mm). Thirty participants of the 39 with no hematuria at our first examination (77%) showed microcalculi or calculi at renal sonography. The patients with microcalculi were significantly older than were those without microcalculi. During the follow-up, 4 of 26 children never had hematuria and 8 had no hematuria during most of the follow-up period. Two patients who had a calculus at first visit and 3 who formed calculi 4 to 12 mm in diameter, after 1 to 3.5 years subsequently passed them in the urine.

CONCLUSIONS

The lack of hematuria is not predictive of absence of urolithiasis. Therefore, it may be misleading to judge on the efficacy of a given therapy only based on disappearance of hematuria. HU and hypercalciuria have to be suspected in children with dysuria and those with recurrent abdominal/flank pain and familial history of urolithiasis, although they have no hematuria.

Clinical presentation and natural course of idiopathic hypercalciuria in children

Idiopathic hypercalciuria (IHC) has been reported mainly in children with hematuria in the 1980s and early 1990s, when renal sonography was just becoming routine. The presence of microcalculi, i.e., of hyperechogenic spots < 3 mm in diameter in renal calyces, was not taken into account in those studies. We attempted to outline clinical presentation and natural course of IHC not only in children with hematuria, but also in those with dysuria and/or recurrent abdominal/flank pain and a family history of nephrolithiasis, taking into account the finding of microcalculi. We analyzed retrospectively the data at diagnosis from 74 consecutive children aged 2.4-18 years (mean 8.6) with IHC (calciuria 4.1-15.1 mg kg-1 24 h-1, mean 6.1) and the outcome of 30 of them who were followed > or = 1 years (mean 3.2) with no specific therapy. At diagnosis, 38 patients (51%) had no hematuria, 42 (57%) had microcalculi and four (5%) had calculi. Of the patients with normal urinalysis, 71% had microcalculi or stones. The subjects with microcalculi and those with stones were significantly older than those without microcalculi and stones (P = 0.004 and 0.007). A normal urinalysis at our evaluation and a history of abdominal/flank pain were significantly more frequent in patients with microcalculi than in those without (P = 0.02 and 0.0001, respectively). During the follow-up, four of 30 patients formed stones 1-3 years after first diagnosis of IHC. More than half of children with IHC have microcalculi. The risk of formation of microcalculi or stones increases with age. The lack of hematuria does not exclude the presence of microcalculi or calculi. Hypercalciuria has to be suspected in children with dysuria and/or recurrent abdominal flank pain and a family history of nephrolithiasis, even when they have no hematuria.

Idiopathic hypercalciuria and hyperuricosuria: family prevalence of nephrolithiasis

We studied the prevalence of a history of nephrolithiasis in first- and second-degree relatives of 74 children with hypercalciuria (HC), 61 with hyperuricosuria (HU), and 41 with HC plus HU, and in a control population of 261 children with different diseases. Family history of nephrolithiasis was found in 69% of HC, 75% of HU, 78% of HC plus HU, and 22% of control patients. The prevalence was not different among HC, HU, and HC plus HU groups, but was significantly higher in each study group than the control group (P=0.0001). Body mass index >95th percentile was found in only 4.7% of the patients with HC or HC plus HU. Calculi (>3 mm in diameter) were present in 8.9% of the patients with a family history of nephrolithiasis and in 9.4% of those with no family history (P=0.85). Microcalculi (<3 mm in diameter) were found by sonography in 56.6% of the patients with and in 53.3% of those without a family history of nephrolithiasis (P=0.83). Children with HC and/or HU have a strong familial prevalence of nephrolithiasis. Obesity does not seem to affect the association of familial nephrolithiasis and hypercalciuria in children. The presence of nephrolithiasis in families of children with HC and/or HU is not associated with a higher rate of formation of calculi or microcalculi.

High incidence of a generally small kidney and primary vesicoureteral reflux

PURPOSE

We distinguished the scintigraphy pattern of congenital reflux nephropathy from that of acquired scarring in children with primary vesicoureteral reflux.

MATERIALS AND METHODS

We retrospectively evaluated the frequency and pattern of renal scintigraphy abnormalities in 41 patients with prenatally detected primary vesicoureteral reflux and in 322 with a mean age plus or minus standard deviation of 3.6 + or - 1 years in whom primary reflux was detected after urinary tract infection. Dimercapto-succinic acid scintigraphy was performed 4 to 6 and 1 to 4 months after reflux was diagnosed and/or the infection was cured in patients with urinary tract infection and prenatal detection, respectively.

RESULTS

We identified 3 patterns of renal damage, including overall decreased uptake of renal radionuclide that was 20% to 40% of relative uptake, focal defects in uptake and shrunken kidney with relative uptake less than 20%. Scintigraphy revealed renal damage in 12 prenatally detected cases of vesicoureteral reflux, including overall decreased uptake in 58% and shrunken kidney in 42%, and in 111 cases of reflux detected at urinary tract infection, including overall decreased uptake in 50%, uptake focal defects in 37% and shrunken kidney in 13%. In the urinary tract infection group overall decreased uptake was present in 25 of 90 boys and in 40 of 232 girls (p = 0.05). Of these children 15% of the girls had uptake focal defects and 17% had overall decreased uptake. Overall decreased uptake and uptake focal defects were significantly more common in kidney-ureter units with reflux grade 4 or greater than in those with grade 3 or less (p = 0. 00001 and 0.027, respectively).

CONCLUSIONS

When assuming that overall decreased radionuclide uptake indicates congenital reflux nephropathy and uptake focal defects indicate postnatal acquired scarring, congenital reflux nephropathy appears to be an important cause of renal damage in children with primary vesicoureteral reflux even beyond the neonatal age and even in girls. This finding is of interest because postnatally acquired scarring may but congenital reflux nephropathy may not be prevented.

Enhanced detection of vesicoureteric reflux with isotopic cystography

We compared the accuracy of isotope cystography (IC) and fluoroscopic cystourethrography (FC) in detecting vesicoureteric reflux (VUR) in children. FC and IC were performed in 124 children, 56 boys and 68 girls, aged 1 month to 9.2 years (mean 2.1 years), admitted consecutively for suspected VUR over a 10-month period. VUR was diagnosed by one or both studies in 51 of 124 (41%) patients. The two methods were concordant for the detection of VUR in 84% of kidney-ureter units and in 93% for the detection or exclusion of severe VUR. IC detected VUR more accurately than FC, both when all grades of VUR were considered together (P=0.00001) and when only severe reflux was considered (P=0.004). VUR was missed by FC in 23 of 51 (45%) subjects. Of those 23, 12 had severe VUR detected on one side at least by IC. VUR was missed by IC in 3 subjects. IC is significantly more accurate than FC in the initial diagnosis of VUR, even of severe grade. IC is the method of choice for the first diagnosis of VUR. Boys with VUR diagnosed by IC also need FC to investigate for posterior urethral valves.