Antenatal hydronephrosis: infants with minor postnatal dilatation do not need prophylaxis

The aim of this study was to determine the occurrence of urinary tract infection (UTI) in infants with antenatal renal pelvis dilatation (ARPD). Consecutive ultrasound (US) screening of 14,000 pregnant women detected ARPD ≥5 mm in 106 foetuses. After birth, two US examinations were performed: on the fifth to seventh day and during the third week of life. The findings were considered normal when renal pelvis dilatation (RPD) was ≤7 mm on both examinations and no other signs of abnormality were present. Voiding cystourethrography (VCUG) was done in all infants 6–8 weeks after birth. One hundred and three infants were followed for 2 years. Antibacterial prophylaxis (trimethoprim 1 mg/kg per day) was given to those with RPD ≥15 mm, vesicoureteric reflux (VUR) grades III–V and suspected obstruction. In 53/103 babies, both US examinations were normal, three had VUR grade I. Two girls had UTI at 18 and 24 months of age, respectively. Among the 50 infants with abnormal initial US, six had VUR, of which four were high grade (IV–V). All four developed UTI. We conclude that UTI is uncommon in infants with two normal postnatal US examinations. Routine use of antibacterial prophylaxis in these infants therefore cannot be recommended.     

Vesicoureteral reflux in infants with isolated antenatal hydronephrosis

Standardized evaluation of all newborns with antenatally recognized hydronephrosis (ANH) at The Hospital for Sick Children (HSC) has included voiding cystourethrography (VCUG). This paper reviews this protocol to determine: (1) the prevalence of vesicoureteral reflux (VUR) in isolated ANH and (2) the value of performing VCUG in cases of mild hydronephrosis, defined as renal pelvis dilatation <10 mm on postnatal ultrasonography (US). A retrospective chart review was performed on infants referred with ANH. The inclusion criterion was isolated ANH. Exclusion criteria were (1) presence of additional genitourinary abnormalities and (2) no VCUG. Pelviectasis was categorized according to the anteroposterior diameter of the renal pelvis. There were 111 infants with isolated ANH. All except 3 underwent VCUG. There were 68 children (63%) with normal postnatal US or mild pelviectasis (<10 mm). VUR was detected in 16 patients, of whom 10 had mild or absent pelvic dilatation. There was no correlation between the degree of pelviectasis on postnatal US and the presence or severity of VUR (P=0.567 and P=0.802). VUR was detected in 15% of children with isolated ANH, many of whom had normal postnatal US or mild postnatal pelviectasis. VCUG is the only reliable test for detecting postnatal VUR.     

Outcome of isolated antenatal hydronephrosis: a prospective cohort study

The purpose of this study was to report the outcome of infants with antenatal hydronephrosis. Between May 1999 and June 2006, all patients diagnosed with isolated fetal renal pelvic dilatation (RPD) were prospectively followed. The events of interest were: presence of uropathy, need for surgical intervention, RPD resolution, urinary tract infection (UTI), and hypertension. RPD was classified as mild (5-9.9 mm), moderate (10-14.9 mm) or severe (>or=15 mm). A total of 192 patients was included in the analysis; 114 were assigned to the group of non-significant findings (59.4%) and 78 to the group of significant uropathy (40.6%). Of 89 patients with mild dilatation, 16 (18%) presented uropathy. Median follow-up time was 24 months. Twenty-seven patients (15%) required surgical intervention. During follow-up, UTI occurred in 27 (14%) children. Of 89 patients with mild dilatation, seven (7.8%) presented UTI during follow-up. Renal function, blood pressure, and somatic growth were within normal range at last visit. The majority of patients with mild fetal RPD have no significant findings during infancy. Nevertheless, our prospective study has shown that 18% of these patients presented uropathy and 7.8% had UTI during a medium-term follow-up time. Our findings suggested that, in contrast to patients with moderate/severe RPD, infants with mild RPD do not require invasive diagnostic procedures but need strict clinical surveillance for UTI and progression of RPD.     

Children and adolescents with ureteropelvic junction obstruction: is an additional voiding cystourethrogram necessary? Results of a multicenter study

Purpose

The incidence of ureteropelvic junction obstruction (UPJO) and concomitant vesicoureteral reflux (VUR) ranges from 14 to 18 %. Therefore, different guidelines recommend a voiding cystourethrogram (VCUG) to identify cases of VUR early in the diagnostic process. Aim of this multicenter study was to reassess the incidence of concomitant VUR and the need for additional VCUG in a large cohort of patients with UPJO. Furthermore, we asked for clinical objectives that defined the need for VCUG with the intention of minimizing radiation exposure and the need for invasive diagnostic procedures.

Methods

Medical records for 266 patients (69 girls, 197 boys) with UPJO were analyzed retrospectively. Data were obtained on gender, clinical symptoms, results of pre- and postnatal ultrasound, VCUG and 99^mTechnetium-MAG3 (MAG3) scan. They were correlated with the incidence of concomitant VUR.

Results

One hundred and seventy-eight patients (67 %) underwent VCUG. Concomitant VUR was detected in 13 patients. Dilating VUR (dVUR) was observed in 11 patients. In our study, the overall incidence of a concomitant VUR was 7.3 %. In cases of proven VUR, we observed a positive predictive value for female gender, ureteral dilatation, renal insufficiency, and recurrent urinary tract infections (UTI). But there was no correlation between concomitant VUR and the severity of hydronephrosis.

Conclusions

Our data suggest that the low incidence of concomitant VUR in cases of UPJO does not justify the routine use of VCUG as a routine diagnostic tool. Especially, ureteral dilatation and recurrent UTI have a positive predictive value for concomitant VUR.     

Outcome and management of isolated severe renal pelvis dilatation detected at postnatal screening

The aim of this study was to evaluate the incidence and outcome of isolated severe renal pelvis dilatation (RPD; APD > 15 ≤ 20 mm) in an unselected population of 2-month-old infants prospectively followed up for 12–14 months of life. Isolated severe renal pelvis dilatation was detected in 46 of the 11,801 (0.39%) infants screened. Nephro-urological investigations were initiated if RPD persisted, or if urinary tract infection (UTI) occurred during follow-up, and antibiotic therapy was administered only when UTI occurred. At follow-up, RPD persisted in 24 infants. Of these, 8 infants presented with vesico-ureteral reflux (VUR) of grade ≥ 3 and 16 with ureteropelvic junction obstruction (UPJO). Incidence of UTI was significantly higher (p < 0.001) in infants of the study group than in infants of the control group (13.9 vs 2.5%). Our data suggest that isolated severe RPD may be a self-limiting condition and that antibiotic prophylaxis (AP) for the prevention of UTI should not be performed. Considering RDP resolution and the incidence of UTI during follow-up, investigations for uropathy in infants with isolated, severe RPD are justified in persistent cases, or when UTI occurs during follow-up. Careful clinical monitoring for signs of UTI and treatment of each episode of UTI may be sufficient and safe.     

Neonates with extra-renal pelvis: the first 2 years

Extra-renal pelvis (ERpel) is a common ultrasonographic finding among neonates who have undergone recurrent ultrasound examinations for a better definition of prenatal renal pelvic dilatation. This study tries to determine whether or not ERpel has important prognostic implications. Seventy-nine neonates (17 female) were examined. All had a diagnosis of prenatal renal pelvis dilatation, which was shown by postnatal ultrasound to be ERpel. Sixty ERpel neonates were examined 1.5 months to 2.5 months after the ultrasound (US) diagnosis by both Tc-99m diethylene triamine penta-acetic acid (DPTA) dynamic renal scanning and ^99mTc-pertechnetate direct cystography. Clinical assessment, urine cultures and renal ultrasound follow-up were maintained for 2 years. The proportion of urinary tract infections (UTIs) in patients with ERpel was compared with that of the total neonatal and infantile population with normal US scans in the region of our hospital. Associated minor congenital malformations were found in 12 of 79 neonates (15.2%). Four had a family history of ERpel. Among 60 neonates who underwent renal scanning, 36 (60%) were found to have urinary retention in the collecting system. Another nine (15%) had vesico-ureteral (VU) reflux, of which seven had urinary retention. Fifteen (25%) showed normal isotope imaging. Urinary tract infection was diagnosed in 16 ERpel neonates in whom only one exhibited VU reflux (grade 2). The incidence of neonatal UTI in the ERpel group was more than that of either neonatal or infantile UTI in those with normal US scans in the local population (20.2% vs 1.2% and 4.3%, respectively). Fifty-three infants completed a 2-year follow-up. Repeat renal ultrasonography indicated that one infant (1.8%) had developed bilateral hydronephrosis, 12 (22.6%) had unchanged findings, 18 (40%) showed an improvement (decrease of ERpel width or resolution in one side) and, in 22 (41.5%) infants, the condition had resolved. No clinical or kidney function deterioration was observed. Seven patients (13.2%) each had one episode of UTI during the 2-year follow-up period; none of them had VU reflux. Neonatal ERpel is more frequent in male infants. It is associated with greater rates of minor congenital malformations, VU reflux and UTI than in the general population of the same ages. The increased UTI incidence is not attributed to VU reflux.     

Outcome and management of isolated moderate renal pelvis dilatation detected at postnatal screening

The aim of this study was to evaluate the incidence and outcome of isolated moderate renal pelvis dilatation (RPD) [anterior–posterior diameter (APD) 10–15 mm] in an unselected population of 2-month-old infants prospectively followed for up to 12–14 months of life. Isolated moderate renal pelvis dilatation was detected in 282 of the 11,801 (2.4%), infants screened; 240 infants with normal renal ultrasound were enrolled as the control group. Resolution of RPD was considered when an APD ≤ 5 mm was found on two consecutive sonograms. Urological investigations were initiated if the RPD persisted or if urinary tract infection (UTI) occurred during follow-up, and antibiotic therapy was administered only when UTI occurred. The events of interest were resolution of the RPD, presence of uropathy and UTI. At follow-up, RPD persisted only in 18 infants; of these, four infants were diagnosed with vesicoureteral reflux (grade 1–3) and 14 with ureteropelvic junction obstruction. Of the 223 infants with RPD and 230 control infants who completed follow-up, UTI occurred in 3.6 and 2.5%, respectively. The incidence rate of UTI per 1000 person-months was 5.98 episodes in the patient group and 5.22 episodes in the control group. The rate ratio was 1.146 (95% confidence interval 0.389–3.54, p = 0.8). Our data suggest that isolated moderate RPD is essentially a self-limiting condition and that antibiotic prophylaxis for the prevention of UTI should not be performed. A non-invasive ultrasound scan performed during the follow-up is sufficient to diagnose a potentially dangerous and persistent RPD.     

Diagnostic accuracy of postnatal ultrasound screening for urinary tract abnormalities

The study was aimed at (1) the determination of the incidence of abnormalities of the urinary tract in newborn infants detected by postnatal ultrasound screening, and (2) the evaluation of the diagnostic accuracy of postnatal ultrasound screening for detecting surgical urinary tract abnormalities. The prospective study was of full-term neonates born in the University Hospital of Olomouc in 2005–2008 who underwent renal ultrasound screening after 72 h of life. Significant findings were recorded. Subsequent diagnostic and therapeutic procedures were recorded and evaluated in a group of children with detected renal pelvic dilatation (RPD). (1) A total of 6,088 newborn infants was examined. The absolute and relative RPD incidence rates (anteroposterior diameter, APD) were as follows: 5–7 mm, 146 (2.4%); 7–10 mm, 70 (1.15%); 10–15 mm, 13 (0.21%), and 15 mm or more, 5 (0.08%). Of those, 16 children were operated on for abnormalities of the urinary tract, of which nine (56%) had been detected by prenatal screening. Other findings: six cases of unilateral renal agenesis, four cases of multicystic renal dysplasia, four of renal dystopia, one of polycystic kidney disease and one of renal hypoplasia. (2) A group of 224 children with postnatally detected RPD was examined, of whom 40 (17.9%) underwent voiding cystourethrography and/or scintigraphy and 16 (7.1%) were treated surgically. The receiver operating characteristic curves were analyzed, and the areas under the curves were calculated. Postnatal renal ultrasound screening is probably a suitable test for detecting significant urinary tract abnormalities.     

Natural history of bilateral mild isolated antenatal hydronephrosis conservatively managed

Background

The purpose of this study was to assess the prevalence and outcome of newborns with bilateral mild isolated antenatal hydronephrosis managed with neither antibiotic prophylaxis nor voiding cystourethrography (VCUG).

Methods

Inclusion criteria were ultrasonographic evidence of an anterior–posterior pelvic diameter (APPD) of 5–15?mm at the third trimester of gestation and on the first postnatal ultrasound sonogram. Exclusion criteria were an APPD?>15?mm, calyectasis, hydroureteronephrosis, or renal or bladder abnormalities. Ultrasound follow-up was performed. Parents were familiarized with the signs of urinary tract infection (UTI). If UTI was confirmed, VCUG was performed. The outcome was assessed as intrauterine resolution of hydronephrosis, total or partial resolution, stability, or progression.

Results

Hydronephrosis was bilateral in 98 of the 236 newborns (196 hydronephrotic kidneys) with mild isolated antenatal hydronephrosis enrolled in this study. Nine patients had UTI, and none showed reflux. After a mean follow–up of 15?months, 74 kidneys showed intrauterine resolution (38%), 82 (42%) showed total resolution, 13 showed partial resolution, 24 were stable, and 3 showed progression. Bilateral cases represented 42% of mild isolated antenatal hydronephrosis. During the first year of life, 80% of the kidneys showed total hydronephrosis resolution, 9% of patients had UTI, and none of the patients showed reflux.

Conclusions

Antibiotic prophylaxis and VCUG are not mandatory in newborns with bilateral mild isolated antenatal hydronephrosis, but clinical and ultrasound follow-up are recommended during the first year of life.     

Paediatric urinary tract infection and the necessity of complete urological imaging

OBJECTIVE: To evaluate voiding cysto-urethrography (VCUG) in assessing children with urinary tract infection (UTI) when renal/bladder ultrasonography and renal scintigraphy show no abnormality. PATIENTS AND METHODS: A total of 468 renal scintigrams taken in children for an indication of UTI between January 1996 and December 1998 were reviewed. The renal and bladder ultrasonograms of those children with a normal renal scan were then reviewed. Children with both normal renal scans and normal ultrasonography were then evaluated for the frequency and grade of vesico-ureteric reflux (VUR) on VCUG. RESULTS: Of the 468 patients, 453 (97%) had complete imaging studies; 152 of the children evaluated had normal renal scans, of whom 101 had a normal renal ultrasonogram. Twenty-three (23%) children with both a normal renal scan and renal/bladder ultrasonogram showed VUR on VCUG, of whom 14 had bilateral VUR and 13 grade III or higher VUR. CONCLUSION: This study indicates that about 23% of patients may have significant VUR despite both a normal renal scan and ultrasonogram. Therefore, VCUG remains important in evaluating and managing children with UTI.     

Postnatal management of infants with antenatally detected hydronephrosis

With the increasing use of antenatal sonography, fetal hydronephrosis has been reported more frequently. Because of the lack of consensus regarding treatment of these infants, the postnatal approach toward fetal renal pelvis enlargement remains controversial. The aim of this prospective study is to demonstrate the postnatal investigation, treatment, and outcome of infants with prenatally diagnosed hydronephrosis. Infants whose antenatal ultrasound scan showed a fetal renal pelvis of 5 mm or greater were investigated postnatally using ultrasound (US) and voiding cystourethrography. When indicated, isotope studies and intravenous urograms were also performed. We followed prospectively neonates with antenatally diagnosed hydronephrosis and recommended management guidelines on the basis of our findings. In 156 neonates (193 kidney units) that were found to have hydronephrosis, the average gestational age at which the diagnosis was made was 32.94±5.10 weeks. The mean duration of postnatal follow-up was 26.3±13.56 months (range 3–60 months). The mean APPD of the fetal renal pelvis was 10.35±3.24 mm (5–9 mm in 84 kidneys, 10–14 mm in 96 kidneys and 15 mm in 13 kidneys). Of the 193 kidney units, 145 units were found to be pathological. The most common detected underlying abnormalities were ureteropelvic junction obstruction (in 91 kidneys; 62.7%) and vesicoureteral reflux (in 24 kidneys; 16.6%). Postnatally, 23 (45%) of 51 patients whose first US was normal were diagnosed postnatally as having urinary tract abnormality. There was a negative correlation between APPD and the rate of spontaneous resolution and positive correlation between APPD and the rate of surgery (P<0.01). In conclusion, because it is not possible to determine an upper limit of normal for the antenatal renal pelvis, any baby with AH should not be considered clinically insignificant. Infants with antenatal renal pelvis measurements 5 mm should be investigated postnatally. A normal postnatal ultrasound scan does not preclude the presence of urinary tract abnormality.     

Vesicoureteric reflux in the newborn: relationship to fetal renal pelvic diameter

There has been a low yield of primary vesicoureteric reflux (VUR) from screening the fetal urinary tract during obstetric sonography. We sought to determine whether changing the cut-off level of fetal renal pelvic diameter from 10 mm to 4 mm would improve the yield of VUR. In a prospective community-based study, a fetal renal pelvic diameter of 4 mm or more on a transverse view of the fetal renal hilum at obstetric sonography after 16 weeks’ gestation was found in 426 fetuses from 9,800 consecutive pregnancies. After birth, renal sonography was performed on 386 of the 426 babies. Of the 386 babies, 264 (187 boys) had a voiding cystourethrogram (VCUG) at a mean age of 9 weeks. Primary VUR was detected in 33 (16 boys) of the 264 infants (13%), and secondary VUR in another 5 (2%). Only 5 of the 33 (15%) babies with primary VUR would have been detected if a cut-off point of 10 mm for fetal renal pelvic diameter had been used. The prevalence of reflux was similar at each cut-off level of antenatal renal pelvic diameter from 4 to 10 mm. Neither calyceal nor ureteric dilatation was helpful in differentiating those with from those without VUR. The postnatal renal sonogram did not distinguish whether reflux was present or not. More infants with primary VUR, particularly girls, were found by changing the cut-off point for fetal renal pelvic diameter from 10 mm to 4 mm, and performing a VCUG on all such infants even if the postnatal renal sonogram was normal. Of the 33 infants with primary VUR, 9 (27%, 5 boys) had an abnormal dimercaptosuccinic acid scan. Our findings support the screening of the obstetric population for a fetal renal pelvic diameter of 4 mm or more, and then investigating the infants for VUR after birth. Received January 24, 1996; received in revised form November 1, 1996; accepted January 17, 1997     

Unilateral multicystic dysplastic kidney: experience in children

OBJECTIVES: To report a retrospective study of unilateral multicystic dysplastic kidneys (MCDK) in children, assessing the contralateral kidneys and urinary tract, the functional consequences, and the urological and nephrological management and outcome, as unilateral MCDK is the most common cause of renal cystic disease in children, and malformations of the contralateral urinary tract and kidney (pelvi-ureteric obstruction, megaureter, reflux, renal dysplasia) have been reported. PATIENTS AND METHODS: The study included 97 patients (60 boys, 37 girls) with MCDK seen between 1985 and 1998; 82 were diagnosed in utero by ultrasonography (US). After birth, the diagnosis was verified by US, renal scanning (in 93) or intravenous urography (in four), and 89 (92%) had voiding cysto-urethrography (VCUG). Of the 97 children, 87 (90% had a mean (range) follow-up of 44.3 (15-115) months. RESULTS: The MCDK was removed in 17 children; the follow-up of 75 children (five lost to follow-up) showed total involution of the MCDK in 25%, shrinkage in 60% and a stable size in 15%. None had any sign of malignancy. The contralateral kidney showed anomalies in 19 of 97 children (20%); 12 had a dilated renal pelvis (two with megaureter), six had a high echogenicity of the contralateral kidney (one had reflux, and two also pelvic dilatation). In only four of the 89 children was reflux found by VCUG; 16 of the 19 anomalies were detected by US. Five children needed surgery on the contralateral urinary tract (three a pyeloplasty, and one each a pyeloplasty plus ureteroneocystostomy, and an antireflux procedure). Of the contralateral kidneys 43% showed compensatory hypertrophy. There was mild renal insufficiency in three children; renal function seemed to be slightly impaired in many. Five infants had hypertension (four with spontaneous resolution) caused by renal scarring after pyelonephritis or inborn dysplasia of the contralateral kidney. There were symptomatic urinary tract infections in seven children. CONCLUSION: US can be used safely to diagnose unilateral MCDKs and malformations of the contralateral urinary tract and kidney. In cases where US of the dysplastic kidney remains uncertain renal scintigraphy is necessary to detect the lack of renal function. The low rate of reflux makes routine VCUG unnecessary if the contralateral upper urinary tract and kidney appear to be normal on US. Nephrectomy of the dysplastic kidney in typical cases is also unnecessary. A long-term nephro-urological follow-up of children with MCDK is recommended.     

Evaluation and outcome of antenatal hydronephrosis: a prospective study

Antenatal hydronephrosis (AHN), defined as dilatation of renal pelvis and/or calyces, is the most frequently detected antenatal abnormality. However, postnatal management of AHN is controversial. The purpose of this study was to describe the clinical outcomes of infants with AHN and to contribute to the definition of the postnatal evaluation of these patients. One hundred and thirty-six infants with AHN were prospectively followed up to 18 months. Patients were divided into two groups according to the degree of sonographic hydronephrosis (HN) on days 5-7: group I (n = 87, 64%) included patients who had grades 1 and 2 (64%) and group II (n = 49, 36%) included patients who had grade 3 and above HN. The grade of HN was found to be correlated with the increased risk of urologic pathologies. Frequency of vesicoureteral reflux was found to be significantly lower in patients with mild HN (6%) as compared to patients with severe AHN (29%) (p = 0.005). In addition, the risk of urinary tract infection increases with increasing grades of HN (10% vs. 29%, p = 0.006). The frequency of spontaneous resolution in patients with mild AHN (64%) was also significantly higher than in patients with severe HN (29%) (p < 0.001). The degree of AHN can be used for making decision about further diagnostic imaging and treatment. Our results strongly suggest that low-grade HN is a relatively self-limited condition and needs minimal investigation. In contrast, the outcome of more severe degrees of AHN needs clarification.     

The value of direct radionuclide cystography in the detection of vesicoureteral reflux in children with normal voiding cystourethrography

Background

Vesicoureteral reflux (VUR) is one of the most important risk factors for urinary tract infection (UTI). Diagnosis and treatment of VUR is important to prevent irreversible complications, such as renal scarring and chronic renal failure. This study was conducted to assess the value of direct radionuclide cystography (DRNC) in the detection of VUR in children with UTI and a normal voiding cystourethrography (VCUG).

Methods

DRNC was performed in 35 children with a normal VCUG after an episode of febrile UTI who had hydronephrosis or hydroureter, abnormal acute dimercaptosuccinic acid (DMSA) scan results and/or febrile UTI recurrence. This study was conducted in the nephrology department of Mofid Children’s Hospital, Tehran (Iran).

Results

The results were statistically analyzed. Among the 70 ureters studied, 33 (49.1 %) were observed to have VUR. Of these, 17 (51.5 %) had mild, 14 (42.4 %) moderate, and 2 (6.1 %) severe reflux. A significant relationship was observed between DRNC results and DMSA renal scan findings (P?<?0.05).

Conclusions

Based on our results, we suggest that DRNC may reveal VUR despite a normal VCUG in children with hydronephrosis, abnormal acute DMSA, and/or recurrent febrile UTI.

     

Acute renal damage in infants after first urinary tract infection

Urinary tract infection (UTI) is one of the most common causes of unexplained fever in neonates. The aim of this study was to determine the incidence of urinary tract anomalies and acute renal damage in neonates who presented with first urinary tract infection in the first 8 weeks of life. We reviewed the records of 95 infants, who were hospitalised with UTI during a 6-year period (1994-1999). Patients with antenatally diagnosed hydronephrosis and incomplete radiological investigations were excluded from the study. Of the remaining 57 patients, 42 were boys and 15 girls. The mean age at diagnosis was 32 days (range 5-60 days). All patients underwent renal ultrasonography (US), voiding cystourethrogram (VCUG) and (99m)Tc-dimercaptosuccinic acid (DMSA) scan. Urinary tract abnormalities were detected in 20 (35%) patients. Vesicoureteral reflux (VUR) was found in 19 (33%) neonates, 7 girls and 12 boys. Acute cortical defects on DMSA scan were present in 19 kidneys of patients with VUR and in 25 of those without reflux. Only one-third of neonates after first symptomatic UTI had VUR. We recommend that US, VCUG, and DMSA scan should be routinely performed after the first UTI in infants younger than 8 weeks.     

Evaluation and Outcome of Antenatal Hydronephrosis: A Prospective Study

Antenatal hydronephrosis (AHN), defined as dilatation of renal pelvis and/or calyces, is the most frequently detected antenatal abnormality. However, postnatal management of AHN is controversial. The purpose of this study was to describe the clinical outcomes of infants with AHN and to contribute to the definition of the postnatal evaluation of these patients. One hundred and thirty-six infants with AHN were prospectively followed up to 18 months. Patients were divided into two groups according to the degree of sonographic hydronephrosis (HN) on days 5–7: group I (n = 87, 64%) included patients who had grades 1 and 2 (64%) and group II (n = 49, 36%) included patients who had grade 3 and above HN. The grade of HN was found to be correlated with the increased risk of urologic pathologies. Frequency of vesicoureteral reflux was found to be significantly lower in patients with mild HN (6%) as compared to patients with severe AHN (29%) (p = 0.005). In addition, the risk of urinary tract infection increases with increasing grades of HN (10% vs. 29%, p = 0.006). The frequency of spontaneous resolution in patients with mild AHN (64%) was also significantly higher than in patients with severe HN (29%) (p < 0.001). The degree of AHN can be used for making decision about further diagnostic imaging and treatment. Our results strongly suggest that low-grade HN is a relatively self-limited condition and needs minimal investigation. In contrast, the outcome of more severe degrees of AHN needs clarification.     

Renal pelvic wall thickening in childhood urinary tract infections--evidence of acute pyelitis or vesicoureteral reflux?

OBJECTIVE: The aim of this study was to determine whether renal pelvic wall thickening in active childhood urinary tract infections (UTIs), as demonstrated using ultrasound, is caused by acute pyelitis or by vesicoureteral reflux (VUR)-related chronic changes. MATERIAL AND METHODS: A total of 41 children with at least unilateral renal pelvic wall thickening as demonstrated using ultrasound during the acute stage of UTI, and confirmed using voiding cystourethrography (VCUG), were analyzed. All cases underwent ultrasound studies at 6 months follow-up. RESULTS: Using ultrasound, 50 halves of the pelvis showed renal pelvic wall thickening. In 27 (54%), ipsilateral VUR could be demonstrated using VCUG. The sensitivity, specificity and positive predictive value of renal pelvic wall thickening for predicting ipsilateral VUR were 79.4%, 52.1% and 54%, respectively. Only 2 (7%) cases presented with wall thickening at 6 months follow-up. Most of the thickening recovered after clinical improvement, although VUR became persistent in half the cases. CONCLUSIONS: Renal pelvic wall thickening is an abnormal finding in the acute stage of childhood UTI and predominantly indicates acute pyelitis rather than VUR-related chronic changes. Renal pelvic wall thickening is not sufficiently predictive of VUR in acute UTI, although it does provide evidence of upper UTI.     

Fetal renal pelvic dilatation—poor predictor of familial vesicoureteral reflux

The sensitivity and positive predictive value (PPV) of fetal renal pelvic dilatation for detecting vesicoureteral reflux (VUR) can only be determined by performing voiding cystourethrography (VCUG) on all newborns in a study population. We sought to determine this for infants with a family history of reflux. From June 1989 to September 1996, 157 children (80 males) under 2 years with a family history of primary VUR in a first-degree relative had VCUG. VCUG results were compared with the fetal renal pelvic diameter on obstetric sonogram performed after 16 weeks gestation. Of the 157 infants, 33 (11 boys) had primary VUR. In those with a parent as the index case, the prevalence of reflux was 5% in boys and 35% in girls (P=0.03). The largest renal pelvic diameter after 16 weeks was not discriminatory for VUR, but after 30 weeks gestation a 4 mm renal pelvis had a sensitivity of 33% and a PPV of 32%. The sensitivity was higher for grades 4 and 5 (75%) than for grades 1–3 reflux (17%), (P=0.04). In conclusion, fetal renal pelvic diameter has a low sensitivity and poor predictive value for detecting VUR, but this improves a little after 30 weeks gestation.     

Screening high-grade vesicoureteral reflux in young infants with a febrile urinary tract infection

Background

The lack of good evidence for improved outcomes in children and young infants with febrile urinary tract infection (UTI) after aggressive treatment for vesicoureteral reflux (VUR) has raised doubts regarding the need for routine voiding cystourethrography (VCUG), and the appropriate imaging evaluation in these children remains controversial.

Objectives

This prospective study aimed to determine whether abnormalities found on acute dimercaptosuccinic acid (DMSA) scan and ultrasound (US) can help indicate the necessity of voiding cystourethrography (VCUG) in young infants.

Methods

For 3.5?years, all infants younger than 3?months presenting with first febrile UTI were prospectively studied. All infants were hospitalized and investigated using US (<3?days after admission), DMSA scan (<5?days after admission), and VCUG (7–10?days after antibiotic treatment) after diagnosis. The association among findings of US, DMSA scan, and VCUG were evaluated.

Results

From 220 infants, there were abnormal results in 136 (61.8%) US and in 111 (50.5%) DMSA scans. By US, ten infants (4.5%) with abscess or structural abnormalities other than VUR were diagnosed. High-grade (III–V) VUR was present in 39 patients (17.7%). The sensitivities for high-grade VUR of renal US alone (76.9%) or DMSA scan alone (82.1%) were not as good as that of the “OR rule” strategy, which had 92.3% sensitivity and 94.3% negative predictive value.

Conclusions

To screen high-grade VUR in young infants with febrile UTI, US and acute DMSA scan could be performed first. VCUG is only indicated when abnormalities are apparent on either US or DMSA scan or both.