Vesicoureteral Reflex Research Articles

Optimal bacterial colony counts for the diagnosis of upper urinary tract infections in infants.

There are no consensus criteria for diagnosing upper urinary tract infections (UTI). Therefore, we conducted a study to assess whether bacterial colony counts of ≥ 103CFU/ml are optimal for diagnosing upper UTIs among infants. This retrospective observational study included 673 patients (<4months of age) with urine samples obtained by catheterization for bacterial cultures. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were obtained when cutoff values of 103, 104, and 105CFU/ml were used for diagnosing upper UTIs. Upper UTI patients were divided based on cutoff values: Group A (103CFU/ml), Group B (104CFU/ml), and Group C (≥ 105CFU/ml). Of the 197 positive (≥ 103CFU/ml) patients, 92 were diagnosed with an upper UTI. These patients were divided into Group A (n = 23), Group B (n = 16), and Group C (n = 53). No significant differences were detected in terms of clinical findings, including the incidence of vesicoureteral reflex. When cutoff values of 103, 104, and 105CFU/ml were used for diagnosing upper UTIs, the sensitivity/specificity percentages were 100/81.3, 75.0/95.9, and 57.6/97.5, and the PPVs/NPVs were 46.7/100, 75.0/95.9, and 79.1/93.4. Using ≥ 105CFU/ml as a diagnostic threshold leads to approximately 40% of positive cases being missed. In contrast when ≥ 103CFU/ml is used, all upper UTIs were identified. Therefore, bacterial colony counts of ≥ 103CFU/ml should be considered the cutoff value for the diagnosis of upper UTIs in infants (< 4months of age).

Indication for voiding cystourethrography during first urinary tract infection.

There is confusion surrounding the precise indications for voiding cystourethrography (VCUG) during the assessment of vesicoureteral reflex (VUR) after a first febrile urinary tract infection (UTI). The aim of this study was to determine the combination of clinical, laboratory and ultrasonography factors correlating with grades IV-V VUR in young children with a first febrile UTI. Children 0-24 months of age who were brought to the emergency department at National Center for Child Health and Development with the diagnosis of first time febrile UTI between March 2004 and May 2011, were enrolled. We compared clinical, laboratory and ultrasonography findings between children with grades IV-V VUR (high-grade VUR) and those with no or grades I-III VUR (normal or low-grade VUR). A total of 231 patients were eligible and 19 had high-grade VUR. Poor clinical appearance, presence of a uropathogen other than Escherichia coli, positive blood culture, hydroureter and thickened renal pelvic wall were all independently associated with high-grade VUR. When one or more of these factors were present, sensitivity, specificity, positive or negative predictive value, and positive or negative likelihood ratio were 94.7%, 69.4%, 23.1%, 99.3%, 3.1 and 0.1, respectively. When none of the factors was present, the proportion of high-grade VUR was 0.7%; if one factor, 11.3%; two factors, 55.6%; three factors, 85.7%. In the absence of five specific factors during the first febrile UTI episode in young children, VCUG is not necessary to detect high-grade VUR. When more than one factor is present, however, VCUG is indicated.

Nephroprotective therapy with angiotensin converting enzyme inhibitors effect evaluation on the course of chronic kidney disease in children with urinary system congenital malformations

The aim : to evaluate the effect of angiotensin-converting enzyme inhibitor (ACEI) therapy on the course of chronic kidney disease (CKD) in children with urinary system congenital malformations. Patients and methods . 119 patients with urinary system congenital malformations aged 3 to 18 years were examined. A control group of 10 clinically healthy children. There were 3 groups: I - 55 children with congenital vesicoureteral reflex, II - 34 children with congenital hydronephrosis, III - 30 children with other forms of urinary systems dysembryogenesis. ACEI therapy Enap (KRKA, Slovenia), held for 6 months (children up to 14 years at a dose of 0.2 mg/kg/24 h in 1 reception, adolescents 5-10 mg/24 h in 1 reception). Results . were evaluated according to clinical data, according to the daily monitoring of blood pressure (BP), renal function, renin concentration, plasma aldosterone. Renin and aldosterone production was determined in blood plasma (lying down) by enzyme immunoassay. Results . During ACEI treatment in all children there was stabilization of BP, renal function improvement. Patients with hypertension showed a significant decrease in the concentration of renin. ACEI therapy leads to normalization of aldosterone concentration in patients with hypertension and without hypertension. Conclusion. The analysis of the course of CKD in patients with US CM on the background of ACEI therapy demonstrates the main aspects of the anti-fibrotic action of the pharmacological blockade of the renin-aldosterone ACEI system.

Association between angiotensin converting enzyme gene insertion/deletion polymorphism and renal scar risk in children vesicoureteral reflex: a reappraise meta-analysis.

Vesicoureteral reflex(VUR) is a common disease in children. Some studies indicated that the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism associated with the renal scar in VUR, but not all researchers agreed with it. To clarify the effect of ACE I/D polymorphism on renal scar risk in children with VUR, we performed the present meta-analysis. PubMed, CNKI, CBM, and Embase databases were searched for studies that examined the relationship between ACE I/D polymorphism and renal scar risk in children with VUR. The Stata 12.0 software was used for statistical analyses. 11 case-control studies with 1,032 VUR patients were analyzed. The results showed that the DD genotype and D allele were associated with renal scar risk in overall VUR patients, DD vs. DI + II: OR = 1.61, 95% CI = 1.04–2.49, P = 0.03; DD vs. II: OR = 1.78, 95% CI = 1.20–2.65, P < 0.01; D vs. I: OR = 1.38, 95% CI = 1.02–1.86, P = 0.04. Similar results were revealed in Turks, but not in Caucasians and Asians. Our meta-analysis indicated that the ACE DD genotype may increase the risk of renal scar in children with VUR.

Small colony variant of Escherichia coli isolated from a recurrent urinary tract infection- a case report

Introduction: Small colony variant of Escherichia coli may cause persistent and recurrent infections in human. These slow growing phenotypic variants are difficult to identify and mislead the diagnosis which can lead to choice of inappropriate antibiotics. In this case report we are presenting a case of recurrent urinary tract infection which was associated with small colony variants of E. coli.Case presentation: A two year old male child was admitted to the hospital with a complaint of passing thin stream of urine. One month earlier the child had been previously diagnosed with bilateral grade five Vesicoureteral reflux. Child had developed recurrent urinary tract infection caused by small colony variants of E. coli.Conclusion: child had undergone bilateral ureter reimplantation as part of treatment to Vesicoureteral reflux. Since vesicoureteral reflex condition is one of the risk factor to develop urinary tract infections. Repeated exposure to antibiotic might have been induced stress condition to bacteria and emerged as slow growing sub population of E. coli.

Urosepsis Occurred in an Infant with Uteropelvic Junction Obstruction and Severe Hydronephrosis

To present a case of severe hydronephrosis, left demonstrated by antenatal sonography in a 1-month-old male infant who took prophylactic antibiotics with amoxicillin for one month since the 3rd day after his birth. Fever occurred after discontinuing the prophylactic antibiotics for 2 days while no vesicoureteral reflex (VUR) was confirmed. Urosepsis with Escherichia coli was later found. Ureteropelvic junction obstruction (UPJO), left with grade 4 hydronephrosis was diagnosed after performing percutaneous nephrostomy and antegrade pyelography. Then, dismembered pyeloplasty was done to cleave the ureteropelvic junction obstruction. The treatment in infants with UPJO, including the options of prophylactic antibiotics and indication of surgery, is discussed in this essay.

Review of 86 Patients With Myelodysplasia and Neurogenic Bladder Who Underwent Sigmoidocolocystoplasty and Were Followed More Than 10 Years

We reviewed the long-term outcome of sigmoidocolocystoplasty. The records of 86 patients who underwent sigmoidocolocystoplasty with a followup of more than 10 years were reviewed, focusing on histopathology, renal function, vesicoureteral reflux, bladder stones and urinary continence. We developed a urinary continence evaluation score, calculated as the postoperative minus the preoperative urinary continence score, including 0-incontinence, 1-severe leakage, 2-moderate leakage, 3-mild leakage, 4-almost dry and 5-dry, for patient self-assessment of urinary continence. A score of 2 or more meant improvement and a score of less than 2 meant no improvement. Mean followup was 13.1 years (range 10 to 21). Histopathology showed inflammation in all cases, hyperplasia in 9 and metaplasia in 4. In 80 of 86 cases creatinine clearance was normal. Ureteral reimplantation had been performed before sigmoidocolocystoplasty in 9 cases (13 kidneys) for grades III to V vesicoureteral reflux, which recurred as grade I in 1 (1 kidney). Ureteral reimplantation was performed during sigmoidocolocystoplasty in 31 cases (58 kidneys) and grades I to II vesicoureteral recurred in 5 (6 kidneys). Of the remaining 44 sigmoidocolocystoplasty cases there were 2 (2 kidneys) of grade I vesicoureteral reflux. On (99m)technetium-dimercapto-succinic acid scintigraphy there was increased renal scarring in 8 cases. Bladder stones were identified in 18 of 86 cases during followup but they were absent at review. The urinary continence evaluation score showed improvement in 61 cases and no improvement in 25. Our results suggest that sigmoidocolocystoplasty is safe and effective in the long term.

Lich-Gregoir Reimplantation Causes Less Discomfort than Politano-Leadbetter Technique: Results of a Prospective, Randomized, Pain Scale-Oriented Study in a Pediatric Population

ObjectiveThere is a consensus that transvesical reimplantation is more appropriate in cases of bilateral vesicoureteral reflex (VUR). In contrast to that it is not yet clear which approach should be used in unilateral VUR. This prospective, randomized trial compared the benefits and drawbacks of the intravesical and extravesical techniques in terms of operative comorbidity. MethodsForty-four children (29 girls, 15 boys, mean age, 67.23 mo) with unilateral VUR were assigned to two groups: 22 patients underwent Lich-Gregoir reimplantation and 22 underwent the intravesical Politano-Leadbetter technique. Follow-up evaluation included renal ultrasonography and voiding cystourethrography (VCUG) 6 mo postoperatively. The groups were compared for operative time, duration of hematuria, upper tract dilation, discomfort and pain, analgesic requirements, voiding dysfunction, and reflux persistency. ResultsNo child had persistent VUR. Contralateral °II VUR was noted in five patients without significant difference regarding the treatment (p=0.345). It was transient in all cases. Operative time was shorter using the extravesical technique (66.73min versus 79.28min; p<0.0001). Gross hematuria occurred only after intravesical reimplantation lasting 4.19 d (p<0.00001). The objective pain score was worse after intravesical surgery (p=0.002). Analgesic requirements were higher after the Politano reimplantation (p=0.039). ConclusionsBoth unilateral extravesical and intravesical reimplantation definitively correct VUR. The mean operative time was significantly shorter using the Lich-Gregoir technique, which underlines its simplicity; additionally, gross hematuria can be avoided. Postoperative pain and bladder spasms were reduced using the extravesical approach. Consequently, it represents an effective surgical technique to correct reflux while operative morbidity is low. Therefore it is the method of choice in cases of unilateral VUR requiring correction.

ぼうこう尿管逆流現象における腎血流速度の検討 （第２報） レノグラムとの比較検討を加えて

膀胱尿管逆流現象 (以下VUR) 患児における腎血流速度の検討を行い，第1報として報告した1)。萎縮や瘢痕を認める腎臓では，有意に収縮期最高血流速度 (以下Vmax)が，低下していた。その結果より，VUR患児における腎血流速度の計測は，腎内の瘢痕や萎縮を検出するうえで有用な情報をもたらすと考えられた。今回は，99mTc-DTPAを用いたレノグラムで得られた，第I相の開始より第II相のピークまでの時間であるTmax (renal transit time) と腎血流速度との相関の検討などを行い，統計学的に有意の相関が得られた。よって，腎血流速度の計測結果は，客観性をもった検査であることが裏づけられたと考えられた。第1報とあわせて，VUR患児における腎血流速度の計測は，診断や経過観察する際の手術適応の判断などに有用な情報を提供すると考えられた。

Management of vesicoureteral reflux secondary to neurogenic bladder.

The authors encountered 108 cases of vesicoureteral reflex (VUR) in 231 cases of neurogenic bladder complicating spina bifida. Bladder compliance and percent volume (% vol.) were measured pre- and postoperatively and the patients were divided into four groups retrospectively according to the treatment. Ninety-five percent of low-grade VUR (grades I and II) disappeared spontaneously with conservative therapy or after augmentation cystoplasty without antireflux surgery; 92% of high-grade VUR (grade III or more) required ureteral reimplantation with or without bladder augmentation. Reflux did not recur in any case of ureteral reimplantation with bladder augmentation, however, it did recur in 20.4% of the cases of simple ureteral reimplantation without bladder augmentation. Percent volume and bladder compliance in cases of recurrence following simple ureteral reimplantation were significantly lower than in the successful cases. This study suggests that low-grade VUR can resolve spontaneously with conservative therapy or with a suitable maneuver to improve bladder compliance. High-grade reflux in cases of preserved bladder volume (% vol.>75%) and compliance (>7 ml/cmH2O) can be treated successfully with simple ureteral reimplantation, however, in cases of low volume (% vol.<60%) and low compliance (<4 ml/cmH2O), reimplantation with bladder augmentation is recommended.

Defining Inoculation Conditions for the Mouse Model of Ascending Urinary Tract Infection that Avoid Immediate Vesicoureteral Reflux yet Produce Renal and Bladder Infection

A satisfactory mouse model of ascending urinary tract infection (UTI) must avoid inoculation-induced vesicoureteral reflex (VUR) yet still produce kidney and bladder infection in a substantial proportion of mice. To define inoculation conditions that would satisfy both these conditions, mice were evaluated for VUR immediately after inoculation under a variety of conditions and were assessed for kidney and bladder infection 48 h after inoculation. Elimination of VUR required a slowed infusion rate, a reduced inoculum volume (25 microliter), and use of less traumatic methods for euthanasia and organ harvest. Bladder and kidney infection were highly prevalent at 48 h among mice inoculated under VUR-free conditions with either of 2 wild type Escherichia coli strains. Together with reports from other investigators, these findings indicate that satisfactory experimental conditions for the mouse model of ascending UTI can be defined empirically but may be laboratory-specific.

Imaging of children with urinary tract infection: a tailored approach

We reviewed the initial imaging studies of 283 children with urinary tract infection in order to decide on the most effective approach. A voiding cystogram was performed in all, complemented by either urography (147 patients), ultrasonography (65), or both (71 patients). In the latter group there was good correlation between sonographic and urographic findings, except for a more accurate delineation of renal scars and anomalies on urography, all in children with vesicoureteral reflux and/or abnormal sonograms. From these data we derived two imaging sequences tailored to the clinical circumstances: cystography as the initial study in ambulatory patients after infection has subsided, and sonography followed by cystography in children hospitalised with severe infection. The upper tracts are studied by ultrasonography and/or urography in patients with significant vesicoureteral reflex or an abnormal sonogram. Both these sequences reduce radiation by omitting the urogram in roughly half of the patients.

The Genitourinary System in Patients With Imperforate Anus

The incidence and significance of associated genitourinary abnormalities was reviewed in a series of 484 infants with imperforate anus encountered over a 17-year period. Fourteen percent of the entire series had significant bilateral upper tract urinary abnormalities (either asymetric or symetric). Of 67 such patients only 14 had combinations of renal agenesis and hypoplasia-dysplasia representing uncorrectable renal pathology. A high incidence of vesicoureteral reflex and neurovesical dysfunction represent additional important sources of preventable renal deterioration.

The genitourinary system in patients with imperforate anus

The incidence and significance of associated genitourinary abnormalities was reviewed in a series of 484 infants with imperforate anus encountered over a 17-year period. Fourteen percent of the entire series had significant bilateral upper tract urinary abnormalities (either asymmetric or symmetric). Of 67 such patients only 14 had combinations of renal agenesis and hypoplasia-dysplasia representing uncorrectable renal pathology. A high incidence of vesicoureteral reflex and neurovesical dysfunction represent additional important sources of preventable renal deterioration.

Changes in ureteral peristaltic activity induced by various stimuli

AbstractThe interaction between the urinary bladder, the kidneys, and ureters is an area of interest to many investigators. Several investigators have suggested the existence of a feedback control system which would regulate urine production by the kidney and urine transport by the upper tract system. In certain conditions, such as urinary bladder outlet obstruction, this system would adjust the production and flow of urine as the situation dictates. The present study was designed to investigate the effects of changes in detrusor pressure, electrical stimulation of the pelvic nerves and the hypogastric nerves, and drugs on ureteral peristaltic activity and on renal nerve electricial activity. Cats anesthetized with alpha chloralose were monitored for changes in ureteral peristaltic frequency or spontaneous firing in renal nerves during changes in detrusor pressure, pelvic and hypogastric nerve stimulation, or drug administration.Increases in detrusor pressure decreased ureteral activity, while pelvic nerve and hypogastric nerve stimulation had little effect on renal nerve firing or ureteral peristaltic activity. Attempts were made to elicit changes in ureteral activity by the administration of acetylcholine, adenosine, adenosine nucleotides, and substance P. Acetylcholine increased and the purines decreased ureteral peristaltic frequency. Atropine and theopylline were used to antagonize the effects of drugs on ureteral peristaltic frequency. Theophylline antagonized only the adenosine responses.This study indicates that there is some interaction between the organs of the cat urinary tract. The results suggest the existence of a vesicoureteral reflex. However, the actual neural pathway for this reflex is still unproven. In addition, the evidence indicates the involvement of purines as neurotransmitters or neuromodulators in this reflex.

Autoimmune responses to Tamm-Horsfall protein in the pathogenesis of chronic pyelonephritis.

Although the role of bacterial infection as the major determinant in the development of acute pyelonephritis has been well documented for years, the nature of the renal scarring typical of chronic "atrophic" pyelonephritis has been a matter of controversy for at least three decades. In the past, recurrent bacterial infection of the kidney was thought to be responsible for the pathologic entity of "chronic pyelonephritis." However, more recent studies suggest that recurrent bacteriuria, in the absence of some form of obstructive uropathy, rarely produces chronic pyelonephritis. The close association between vesicoureteral reflex and chronic pyelonephritis has also been firmly established and has been observed to occur frequently in the absence of urinary tract infection. However, the mechanism by which vesicoureteral reflux injures the kidney has not been firmly established. A number of observations have suggested that some normal component of urine, particularly Tamm-Horsfall protein, might serve as an antigenic determinant involved in the immunopathogenesis of renal scarring in vesicoureteral reflux. The present studies were designed to investigate the immunopathogenic role of Tamm-Horsfall protein in a rabbit model of tubulointerstitial nephritis, and in a swine model of reflux nephropathy. The immune responses to Tamm-Horsfall protein in patients with recurrent nephrolithiasis were also examined, as were the antigenic similarities between Tamm-Horsfall protein and protein-containing components of uropathic bacteria. The results of these studies indicate that autoimmune responses to Tamm-Horsfall protein may occur after exposure to Tamm-Horsfall protein by intravenous challenge in rabbits, and by urinary reflux in pigs, as well as in recurrent nephrolithiasis in man.(ABSTRACT TRUNCATED AT 250 WORDS)

Importance of cystourethrography in neonates with imperforate anus

Infants born with imperforate anus have a high incidence of genitourinary anomalies. Vesicoureteral reflex was the most common abnormality in this series. Since these patients often have bacteriuria, this is an important finding. An intravenous pyelogram and voiding cystourethrogram should be part of the evaluation of each neonate with imperforate anus. Persistent cloaca, a frequent finding in the female patients, may require special diagnostic attention.

Medial deviation of the upper pole calyx on the intravenous urogram as an indication of vesicoureteral reflex

Eighty-three intravenous pyelograms were studied to evaluate thinning of the parenchyma on the medial edge of the superior pole of the kidney as an indicator of vesicoureteral reflux. The data indicate that this finding is suggestive of reflux: the greater the difference between the two sides, the more likely the patient is to reflux.

Ureteral function in pregnant women: VI. Bladder and lower ureteral pressures during voiding

In a previous paper, we found an increased incidence of vesicoureteral reflex during pregnancy. In this paper, we studied the behavior of the juxtavesical lower ureter and bladder during micturition in normal pregnancy to correlated their possible alterations with the incidence of reflux. The increases of vesical and lower ureteral pressures during voiding were recorded in normal nonpregnant and pregnant women. The increase of both vesical and lower ureteral pressures is lower in pregnant women than in nonpregnant ones. The weakness of the contraction of the bladder muscle would not press and occlude the intravesical ureter, and the small increase of lower ureteral pressure would not counterbalance the rise of bladder pressure. These mechanisms may be aided by the decrease of elasticity and compressibility of the intravesical ureter already demonstrated by other authors. Under such circumstances, diminished bladder and ureteral pressure during voiding in pregnancy might account for reflux.