Urinary tract infections in children: knowledge updates and a salute to the future

Thiol-Disulfide Homeostasis in Neonatal Patients with Urinary Tract Infection

OBJECTIVE

Urinary tract infection (UTI) is a disease that can cause significant complications in the neonatal period. The thiol-disulfide homeostasis is one of the important antioxidant defense mechanisms. The purpose of this study is to show the relationship between UTI and thiol-disulfide homeostasis in newborns.

STUDY DESIGN

In this prospective study, 40 newborns with UTI and 40 healthy controls were included. Thiol-disulfide tests (disulfide, native thiol, and total thiol levels) and septic screening tests were performed before and after antibiotherapy in UTI group. The control group was selected from healthy newborns who applied to the outpatient clinic.

RESULTS

The C-reactive protein and interleukin-6 levels were higher, while native thiol and native thiol/total thiol ratio were significantly lower in pretreatment group compared with posttreatment and control group. Also, the levels of disulfide, ischemia modified albumin, disulfide/native thiol ratio, and disulfide/total thiol ratio were higher in pretreatment group compared with posttreatment group.

CONCLUSION

The thiol-disulfide homeostasis is an important indicator of oxidative stress during infections. It is valuable to be detected with small amounts of serum in newborns. These molecules can be used to support the diagnosis of UTI in the newborn. Further studies are needed to define the role of thiol-disulfide homeostasis in the UTI of newborn.

KEY POINTS

· The thiol-disulfide homeostasis can be an important indicator of oxidative stress during infections such as UTI.. · The thiol-disulfide homeostasis of newborn is valuable to be detected with small amounts of serum in neonatal period.. · Laboratory tests such as white blood cell count, erythrocyte sedimentation rate, and C-reactive protein are not significantly different in UTIs..

Molecular Study of Escherichia albertii in Pediatric Urinary Tract Infections

Background:

There are insufficient data about the presence of E. albertii as a causative organism in urinary tract infection in pediatric patients. Objective: The present study aimed to detect E. albertii by polymerase chain reaction (PCR) for detection of uidA, mdh, and lysP genes among isolated E.coli from children with urinary tract infection.

Methods:

The present study was a cross-sectional retrograde study which was carried out on 100 isolates of phenotypically confirmed E.coli detected in urine samples of children suffering from urinary tract infection. The isolates were subjected to molecular identification by PCR for uidA, mdh, and lysP genes.

Results:

E. albertii was identified by PCR in 7% of the isolates and E.coli was identified in 93% of the isolates. Two mdh and lysP genes were detected for E. albertii and the uidA gene for E. coli. E. albertii isolates had marked resistance to gentamicin (71.4%), followed by resistance to ciprofloxacin (57.1%), meropenem and imipenem (42.9% each) and ESBL activity by double discs method was reported in 57.1% of the isolates. However, none of the isolates had shown resistance to nalidixic acid and only one isolate had resistance to norfloxacin. There was a statistically insignificant difference between resistance to the used antibiotics such as aztreonam (P=0.083), ampicillin/clavulanate (P=0.5), ciprofloxacin (P=0.69), gentamicin (P=0.3) and ceftazidime (P=1.00).

Conclusion:

The present study highlights the emergence of E. albertii as a pathogen associated with urinary tract infections in children. There is marked antibiotic resistance of this pathogen, especially toward extended spectrum beta-lactams antibiotics. The identification method depends mainly on genetic studies. Further longitudinal studies with large number of patients are required to verify the accurate prevalence of this bacterium.

OUR EXPERIENCE WITH CONTRAST-ENHANCED VOIDING UROSONOGRAPHY

Vesicoureteral reflux (VUR) is one of the most common anomalies of the urinary system in children. Contrast-enhanced voiding urosonography (ceVUS) is one of the best methods in VUR diagnosis. This study compared characteristics associated with VUR specific images and categorized patients according to a particular VUR grade. The study included 183 children. VUR was detected in 38.9% of patients, mean age 1.7±1.1 years. Grade II VUR was most common (60.3%), followed by grade III (29.4%). Study results showed that VUR occurred irrespective of age, gender, previous ultrasound findings, causative agent, and severity of urinary tract infection (UTI). VUR was more common in children with recurrent UTI. In the group of children with the first UTI not caused by Escherichia coli or with recurrent UTI, boys more commonly suffered from severe VUR (grade IV-V; 66.7%), while girls suffered from moderate VUR (grade II-III; 100%). In this study, the incidence of VUR in prenatally diagnosed hydronephrosis was 28.6%. It is necessary to develop an algorithm for the treatment of children after UTI in Croatia, which should include ceVUS. All children with possible VUR should be referred to a specialized center where it is possible to perform ceVUS.

Applying concepts of life course theory and life course epidemiology to the study of bladder health and lower urinary tract symptoms among girls and women

AIMS

Although lower urinary tract symptoms (LUTS) may occur at different periods during the life course of women, a little research on LUTS has adopted a life course perspective. The purpose of this conceptual paper is to demonstrate how life course theory and life course epidemiology can be applied to study bladder health and LUTS trajectories. We highlight conceptual work from the Prevention of Lower Urinary Tract Symptoms Research Consortium to enhance the understanding of life course concepts.

METHODS

Consortium members worked in transdisciplinary teams to generate examples of how life course concepts may be applied to research on bladder health and LUTS in eight prioritized areas: (a) biopsychosocial ecology of stress and brain health; (b) toileting environment, access, habits, and techniques; (c) pregnancy and childbirth; (d) physical health and medical conditions; (e) musculoskeletal health; (f) lifestyle behaviors; (g) infections and microbiome; and (h) hormonal status across the life span.

RESULTS

Life course concepts guided consortium members' conceptualization of how potential risk and protective factors may influence women's health. For example, intrapartum interventions across multiple pregnancies may influence trajectories of bladder health and LUTS, illustrating the principle of life span development. Consortium members also identified and summarized methodologic and practical considerations in designing life course research.

CONCLUSIONS

This paper may assist researchers from a variety of disciplines to design and implement research identifying key risk and protective factors for LUTS and bladder health across the life course of women. Results from life course research may inform health promotion programs, policies, and practices.

Updated Italian recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children

AIM

Our aim was to update the recommendations for the diagnosis, treatment and follow-up of the first febrile urinary tract infection in young children, which were endorsed in 2012 by the Italian Society of Pediatric Nephrology.

METHODS

The Italian recommendations were revised on the basis of a review of the literature published from 2012 to October 2018. We also carried out an ad hoc evaluation of the risk factors to identify children with high-grade vesicoureteral reflux or renal scarring, which were published in the previous recommendations. When evidence was not available, the working group held extensive discussions, during various meetings and through email exchanges.

RESULTS

Four major modifications have been introduced. The method for collecting urine for culture and its interpretation has been re-evaluated. We have reformulated the algorithm that guides clinical decisions to proceed with voiding cystourethrography. The suggested antibiotics have been revised, and we have recommended further restrictions of the use of antibiotic prophylaxis.

CONCLUSION

These updated recommendations have now been endorsed by the Italian Society of Pediatric Nephrology and the Italian Society for Pediatric Infectivology. They can also be used to compare other recommendations that are available, as a worldwide consensus in this area is still lacking.

Urinary Tract Infection in Children

BACKGROUND

Urinary Tract Infection (UTI) is a common infection in children. Prompt diagnosis and appropriate treatment are very important to reduce the morbidity associated with this condition.

OBJECTIVE

To provide an update on the evaluation, diagnosis, and treatment of urinary tract infection in children.

METHODS

A PubMed search was completed in clinical queries using the key terms "urinary tract infection", "pyelonephritis" OR "cystitis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English literature and the pediatric age group. Patents were searched using the key terms "urinary tract infection" "pyelonephritis" OR "cystitis" from www.google.com/patents, http://espacenet.com, and www.freepatentsonline.com.

RESULTS

Escherichia coli accounts for 80 to 90% of UTI in children. The symptoms and signs are nonspecific throughout infancy. Unexplained fever is the most common symptom of UTI during the first two years of life. After the second year of life, symptoms and signs of pyelonephritis include fever, chills, rigor, flank pain, and costovertebral angle tenderness. Lower tract symptoms and signs include suprapubic pain, dysuria, urinary frequency, urgency, cloudy urine, malodorous urine, and suprapubic tenderness. A urinalysis and urine culture should be performed when UTI is suspected. In the work-up of children with UTI, physicians must judiciously utilize imaging studies to minimize exposure of children to radiation. While waiting for the culture results, prompt antibiotic therapy is indicated for symptomatic UTI based on clinical findings and positive urinalysis to eradicate the infection and improve clinical outcome. The choice of antibiotics should take into consideration local data on antibiotic resistance patterns. Recent patents related to the management of UTI are discussed.

CONCLUSION

Currently, a second or third generation cephalosporin and amoxicillin-clavulanate are drugs of choice in the treatment of acute uncomplicated UTI. Parenteral antibiotic therapy is recommended for infants ≤ 2 months and any child who is toxic-looking, hemodynamically unstable, immunocompromised, unable to tolerate oral medication, or not responding to oral medication. A combination of intravenous ampicillin and intravenous/intramuscular gentamycin or a third-generation cephalosporin can be used in those situations. Routine antimicrobial prophylaxis is rarely justified, but continuous antimicrobial prophylaxis should be considered for children with frequent febrile UTI.

Contrast-enhanced voiding urosonography with intravesical administration of ultrasound contrast agent for the diagnosis of pediatric vesicoureteral reflux

Vesicoureteral reflux (VUR) is one of the most common urinary tract anomalies in children. It has been reported that VUR may be associated with reflux nephropathy. Ultrasound contrast-enhanced voiding urosonography (CeVUS) has become a routine diagnostic method for VUR in a number of European countries; however, it is not widely used in China. The aim of the present study was to analyze the clinical application and evaluate the safety of CeVUS as a diagnostic tool for VUR in children in order to establish a standardized operating procedure for CeVUS in pediatric VUR in China. Between August 2016 and October 2017, 90 children who were susceptible to VUR were admitted into the Pediatric Nephrology Department of Tongji Hospital and underwent CeVUS. The SonoVue second-generation USA contrast agent was administered intravesically via a transurethral bladder catheter at a dose of 1 ml. The occurrence of adverse events was monitored. Urine analysis and culture were performed. A total of 90 children (47 female, 43 male; mean age, 36.6 months) with 178 Pelvi-Ureteral Units (PUUs) underwent CeVUS to screen for VUR. VUR was detected in 44/90 pediatric patients (48.89%) and 65/178 PUUs (36.52%) by CeVUS. The grade distribution of the 65 PUUs with VUS was as follows: Grade I, 3; Grade II, 9; Grade III, 14; Grade IV, 22; and Grade V, 17. The accuracy of CeVUS in the present study were consistent with previous reports. No urethral anomalies were detected and there were no adverse events. CeVUS was demonstrated to be a safe, accurate and reliable imaging technique for detecting VUR in high-risk children, including neonates. Results of the present study indicated that CeVUS can be adopted as the primary screening and follow-up method for pediatric VUR diagnoses in China.

Management of Hematuria in Children

Purpose of Review

This paper provides a review of the diagnostic evaluation of both microscopic and gross hematuria, as well as an update on the pathogenesis, clinical features, and treatment strategies for several diseases of the kidneys and urinary tract in which hematuria is a prominent finding. The goal is to provide pediatric providers with a framework through which appropriate and expeditious referral to subspecialty care may be made for definitive treatment.

Recent Findings

Although there has been great heterogeneity in published treatment strategies for many causes of hematuria, the Kidney Diseases Improving Global Outcomes (KDIGO) initiative has recently set forth guidelines for glomerular diseases in particular to provide evidence-based strategies for treatment. In addition, recent advances in the understanding of molecular pathogenesis and long-term clinical outcomes for other non-glomerular diseases has led to updates in treatment strategies summarized in this review.

Summary

As the pediatric primary care provider is often the first point of contact for children with microscopic or gross hematuria, updated knowledge as to the epidemiology and management of several of the various causes of hematuria will improve the care of children by both avoiding extraneous testing and interventions and implementing definitive care (either by expectant management and reassurance or by subspecialty referral) in a timely manner.

Changing outpatient referral patterns in a small pediatric nephrology practice

Background

We have noted a large number of referrals for abnormal kidney imaging and laboratory tests and postulated that such referrals have increased significantly over time. Understanding changes in referral patterns is helpful in tailoring education and communication between specialists and primary providers.

Methods

We performed a retrospective chart review of new patient referrals to Mary Bridge Children’s Nephrology clinic for early (2002 to 2004) and late (2011 to 2013) cohorts. The overall and individual frequencies of referrals for various indications were compared.

Results

The overall number of new visits was similar for early (511) and late (509) cohorts. The frequency of referrals for solitary kidneys and multi-cystic dysplastic kidneys, microalbuminuria and abnormal laboratory results increased significantly (Odds Ratio (OR) and 95% Confidence Interval of OR: 1.920 [1.079, 3.390], 2.862 [1.023, 8.006], 2.006 [1.083, 3.716], respectively) over the time interval while the proportion of referrals for urinary tract infections (UTIs) and vesicoureteral reflux (VUR) decreased by half (OR: 0.472, 95% CI: 0.288, 0.633). Similarly, referrals for urinary tract dilation and hydronephrosis occurred significantly less often (8% versus 6%, OR: 0.737, 95% CI: 0.452, 1.204) with similar changes in referrals for voiding issues (OR: 0.281, 95% CI: 0.137, 0.575). However, these changes were not statistically significant. Frequencies for other indications showed little variation.

Conclusions

Changes in indications for referral likely reflect evolution of practice in management of UTIs and VUR and increased use of imaging and laboratory testing by pediatric providers. These findings have relevance for ongoing education of pediatricians and support the need for collaboration between primary providers and nephrologists to assure the judicious use of resources.

Risk factors for urinary tract infection in children with urinary urgency

Purpose

To identify which independent variable would be strong predictor of febrile urinary tract infection (UTI) in children and adolescents with overactive bladder.

Materials and Methods

A search was made of the institute's database for all patients diagnosed with overactive bladder over the preceding four years. Children and adolescents under 18 years of age with overactive bladder and no neurological or anatomical alterations of the lower urinary tract were included in the study. The independent variables were: sex, age, ethnicity (Brazilians of African descendence/others), the presence of urinary urgency, daytime incontinence, enuresis, frequent urination, infrequent voiding (≤3 voids/day), nocturia, holding maneuvers, straining to void, intermittent urinary flow, constipation and encopresis. An analysis was conducted to identify patients with febrile UTI and subsequently determine predictors of this condition. Univariate and multivariate analyses were performed.

Results

Overall, 326 patients (214 girls/112 boys) were evaluated. The mean age of the patients was 7.7±3.19 years (± standard deviation). The incidence of febrile UTI was 39.2%. Being female and infrequent voiding were factors significantly associated with febrile UTI, both in the univariate and multivariate analyses.

Conclusions

These results show that being female and infrequent voiding constituted significant risk factors for a diagnosis of febrile UTI in these children.

Bladder and bowel dysfunction in children: An update on the diagnosis and treatment of a common, but underdiagnosed pediatric problem

Bladder and bowel dysfunction (BBD) describes a spectrum of lower urinary symptoms (LUTS) accompanied by fecal elimination issues that manifest primarily by constipation and/or encopresis. This increasingly common entity is a potential cause of significant physical and psychosocial burden for children and families. BBD is commonly associated with vesicoureteral reflux (VUR) and recurrent urinary tract infections (UTIs), which at its extreme may lead to renal scarring and kidney failure. Additionally, BBD is frequently seen in children diagnosed with behavioural and neuropsychiatric disorders such as attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Patients with concomitant BBD and neuropsychiatric disorders have less favourable treatment outcomes. Early diagnosis and treatment of BBD are critical to avoid secondary comorbidities that can adversely impact children's kidney and bladder function, and psychosocial well-being. The majority of patients will improve with urotherapy, adequate fluid intake, and constipation treatment. Pharmacological treatment must only be considered if no improvement occurs after intensive adherence to at least six months of urotherapy ± biofeedback and constipation treatment. Anticholinergics remain the mainstay of medical treatment. Selective alpha-blockers appear to be effective for improving bladder emptying in children with non-neurogenic detrusor overactivity (DO), incontinence, recurrent UTIs, and increased post-void residual (PVR) urine volumes. Alpha-1 blockers can also be used in combination with anticholinergics when overactive bladder (OAB) coexists with functional bladder outlet obstruction. Minimally invasive treatment with onabotulinumtoxinA bladder injections, and recently neurostimulation, are promising alternatives for the management of BBD refractory to behavioural and pharmacological treatment. In this review, we discuss clinical presentation, diagnostic approach, and indications for behavioural, pharmacological, and surgical treatment of BBD in children based on a thorough literature review. Expert opinion will be used when scientific evidence is unavailable.

Clinical Management of Urinary Tract Infections

Urinary tract infection (UTI) is a common pediatric infectious disease. It accounts for almost 1% of clinical presentations and 5% to 14% of emergency department visits. UTIs occur throughout all age groups. The age of onset, gender, history, and physical examination results determine treatment and long-term management. The goal of therapy is to prevent recurrent UTI and the potential for renal scarring, chronic renal disease, and any subsequent complications.