Role of Renal Ultrasonography in Predicting Vesicoureteral Reflux and Renal Scarring in Children Hospitalized with a First Febrile Urinary Tract Infection

Evaluating the requirement of ultrasonography for children with their first urinary tract infection

BACKGROUND

Management of urinary tract infection (UTI) in children remains important. It may be the first sign for a possible underlying congenital abnormalities for the kidney and urinary tract (CAKUT). This study examined whether performing renal and bladder ultrasonography (RBUS) only for children who have a pathogen other than E. coli during their first urinary tract infection (UTI), or who experience UTI recurrence, would result in more missed diagnoses of kidney anomalies.

METHODS

Patients aged between 2 months and 2 years who were seen in a tertiary pediatric hospital during a 2-year period and diagnosed with UTI were included. RBUS and voiding cystourethrography (VCUG) were performed according to American Academy of Pediatrics (AAP) guidelines. Afterwards, we looked back and evaluated how often we found kidney problems when we only did a RBUS on patients who had an atypical cause of their first UTI or who had multiple UTIs.

RESULTS

One hundred and seventy-eight patients who were followed up with UTI were included in this study. The isolated pathogen was E. coli in 104 cases (58.4 %) and atypical in 74 cases (41.6 %). VCUG was conducted on 40 patients, and vesicoureteral reflux (VUR) was discovered in 16 cases and ureteropelvic junction obstruction (UPJO) was discovered in 1 case. A different diagnostic approach that required the presence of an atypical pathogen at the first UTI or a fUTI recurrence to perform the RBUS would have missed just two severe kidney anomalies. It was observed that there could be a decrease of 40.4 % in RBUS and at least 20 % in VCUG.

CONCLUSIONS

A diagnostic approach that necessitates the presence of an abnormal pathogen during the initial UTI or a second UTI episode for the RBUS to be carried out would lead to fewer negative ultrasounds with minimal risk of overlooking kidney anomalies.

Conflicting views of physicians and surgeons concerning pediatric urinary tract infection: a comparative review

BACKGROUND

A first febrile urinary tract infection (UTI) is a common condition in children, and pathways of management have evolved over time.

OBJECTIVE

To determine the extent to which pediatricians and surgeons differ in their investigation and management of a first febrile UTI, and to evaluate the justifications for any divergence of approach.

MATERIALS AND METHODS

A literature search was conducted for papers addressing investigation and/or management following a first febrile UTI in children published between 2011 and 2021. Searches were conducted on Medline, Embase, and the Cochrane Controlled Trials Register. To be eligible for inclusion, a paper was required to provide recommendations on one or more of the following: ultrasound (US) and voiding cystourethrogram (VCUG), the need for continuous antibiotic prophylaxis and surgery when vesicoureteral reflux (VUR) was detected. The authorship required at least one pediatrician or surgeon. Authorship was categorized as medical, surgical, or combined.

RESULTS

Pediatricians advocated less imaging and intervention and were more inclined to adopt a "watchful-waiting" approach, confident that any significant abnormality, grades IV-V VUR in particular, should be detected following a second febrile UTI. In contrast, surgeons were more likely to recommend imaging to detect VUR (p<0.00001), and antibiotic prophylaxis (p<0.001) and/or surgical correction (p=0.004) if it was detected, concerned that any delay in diagnosis and treatment could place the child at risk of kidney damage. Papers with combined authorship displayed intermediate results.

CONCLUSION

There are two distinct directions in the literature regarding the investigation of an uncomplicated first febrile UTI in a child. In general, when presented with a first febrile UTI in a child, physicians recommend fewer investigations and less treatment, in contrast to surgeons who advocate extensive investigation and aggressive intervention in the event that imaging detects an abnormality. This has the potential to confuse the carers of affected children.

Kidney Ultrasonography After First Febrile Urinary Tract Infection in Children: A Systematic Review and Meta-analysis

Importance

Controversy exists on the clinical utility of kidney ultrasonography after first febrile urinary tract infection (UTI), and clinical practice guideline recommendations vary.

Objective

To determine the prevalence of urinary tract abnormalities detected on kidney ultrasonography after the first febrile UTI in children.

Data Sources

The MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Central Register of Controlled Trials databases were searched for articles published from January 1, 2000, to September 20, 2022.

Study Selection

Studies of children with first febrile UTI reporting kidney ultrasonography findings.

Data Extraction and Synthesis

Two reviewers independently screened titles, abstracts, and full texts for eligibility. Study characteristics and outcomes were extracted from each article. Data on the prevalence of kidney ultrasonography abnormalities were pooled using a random-effects model.

Main Outcomes and Measures

The primary outcome was prevalence of urinary tract abnormalities and clinically important abnormalities (those that changed clinical management) detected on kidney ultrasonography. Secondary outcomes included the urinary tract abnormalities detected, surgical intervention, health care utilization, and parent-reported outcomes.

Results

Twenty-nine studies were included, with a total of 9170 children. Of the 27 studies that reported participant sex, the median percentage of males was 60% (range, 11%-80%). The prevalence of abnormalities detected on renal ultrasonography was 22.1% (95% CI, 16.8-27.9; I2 = 98%; 29 studies, all ages) and 21.9% (95% CI, 14.7-30.1; I2 = 98%; 15 studies, age <24 months). The prevalence of clinically important abnormalities was 3.1% (95% CI, 0.3-8.1; I2 = 96%; 8 studies, all ages) and 4.5% (95% CI, 0.5-12.0; I2 = 97%; 5 studies, age <24 months). Study recruitment bias was associated with a higher prevalence of abnormalities. The most common findings detected were hydronephrosis, pelviectasis, and dilated ureter. Urinary tract obstruction was identified in 0.4% (95% CI, 0.1-0.8; I2 = 59%; 12 studies), and surgical intervention occurred in 1.4% (95% CI, 0.5-2.7; I2 = 85%; 13 studies). One study reported health care utilization. No study reported parent-reported outcomes.

Conclusions and Relevance

Results suggest that 1 in 4 to 5 children with first febrile UTI will have a urinary tract abnormality detected on kidney ultrasonography and 1 in 32 will have an abnormality that changes clinical management. Given the considerable study heterogeneity and lack of comprehensive outcome measurement, well-designed prospective longitudinal studies are needed to fully evaluate the clinical utility of kidney ultrasonography after first febrile UTI.

Ultrasonography Results in First Urinary Tract Infection During Childhood: Which Age Group Should Be Screened?

OBJECTIVES

To determine the frequency of urinary system anomaly in children aged 0-18 y suffering from first urinary tract infection (UTI) and to establish which age group requires urinary ultrasonography (USG) screening.

METHODS

Age and gender, urine culture, urinary USG, and urological imaging results among 247 children in the 0-18 y age group with a first diagnosis of UTI were investigated retrospectively.

RESULTS

Anomaly was detected at USG in 68 (27.5%) of the 247 patients suffering from first UTI. The most common anomaly was hydronephrosis. Non-E. coli micro-organisms were the pathogenic agents in 61.8% of patients with anomalies detected at USG. Being in the 0-5 y age group (OR: 0.524, 95% CI 0.284-0.970, p = 0.040) and presence of atypical UTI (OR: 4.746, 95% CI: 1.675-13.450, p = 0.003) emerged as independent predictive markers of severe urinary system pathologies on multiple regression analysis.

CONCLUSION

Based on the data in the present study, routine USG screening is recommended for children suffering from first UTI under the age of 5 y and for the children suffering from atypical UTI at all ages.

Predictive score for vesicoureteral reflux in children with a first febrile urinary tract infection

OBJECTIVE

To develop a simple score for predicting vesicoureteral reflux after a first febrile urinary tract infection in children.

METHODS

A retrospective cohort study was conducted for a 12-year period (January 2008 to December 2019), including patients aged <72 months who underwent renal ultrasonography and voiding cystourethrography after a first febrile urinary tract infection. Patients with a history of antenatal hydronephrosis were excluded. The prediction model and score for vesicoureteral reflux were developed using multivariate logistic regression analysis.

RESULTS

Out of 260 patients in total (median age 4 months, 172 boys), 41 (16%) had vesicoureteral reflux. The score was based on four independent risk factors, including age >6 months (odds ratio 2.71, 95% confidence interval 1.27-5.76), presence of sepsis (odds ratio 3.44, 95% confidence interval 1.31-9.04), white blood cell count ≥15 000/mm³ (odds ratio 1.83, 95% confidence interval 0.88-3.8) and abnormal renal ultrasonography results (odds ratio 2.08, 95% confidence interval 1-4.31). A lower probability of vesicoureteral reflux (positive likelihood ratio = 0.66; P = 0.001) was found in the low-risk group (scores 0-2), whereas a higher probability of vesicoureteral reflux (positive likelihood ratio = 2.54; P = 0.001) was found in the high-risk group (scores 3-5). The predictive ability of the model was 70%.

CONCLUSIONS

The scores developed based on the patient characteristics and renal ultrasonography are useful in predicting presence of vesicoureteral reflux after a first febrile urinary tract infection in children and could guide clinicians' decisions to perform additional imaging studies.

Management of Vesicoureteral Reflux: What Have We Learned Over the Last 20 Years?

Vesicoureteral reflux (VUR) is associated with increased risks of urinary tract infection, renal scarring and reflux nephropathy. We review advancements over the last two decades in our understanding and management of VUR. Over time, the condition may resolve spontaneously but it can persist for many years and bladder/bowel dysfunction is often involved. Some factors that increase the likelihood of persistence (e.g., high grade) also increase the risk of renal scarring. Voiding cystourethrography (VCUG) is generally considered the definitive method for diagnosing VUR, and helpful in determining the need for treatment. However, this procedure causes distress and radiation exposure. Therefore, strategies to reduce clinicians' reliance upon VCUG (e.g., after a VUR treatment procedure) have been developed. There are several options for managing patients with VUR. Observation is suitable only for patients at low risk of renal injury. Antibiotic prophylaxis can reduce the incidence of UTIs, but drawbacks such as antibiotic resistance and incomplete adherence mean that this option is not viable for long-term use. Long-term studies of endoscopic injection have helped us understand factors influencing use and the effectiveness of this procedure. Ureteral reimplantation is still performed commonly, and robot-assisted laparoscopic methods are gaining popularity. Over the last 20 years, there has been a shift toward more conservative management of VUR with an individualized, risk-based approach. For continued treatment improvement, better identification of children at risk of renal scarring, robust evidence regarding the available interventions, and an improved VUR grading system are needed.

Accuracy of Ultrasound in Identifying Renal Scarring as Compared to DMSA Scan

OBJECTIVE

To assess the accuracy of renal ultrasound (RUS) in detecting renal scarring (RS).

METHODS

All initial DMSA scans performed from 2006 to 2009 for history of urinary tract infection (UTI) or vesicoureteral reflux (VUR) in patients under 14 years old were identified, and clinical history obtained via chart review. Patients who had RUS within 4 months of DMSA scan and no documented UTI during that interval were included. Decreased uptake of tracer associated with loss of contours or cortical thinning defined a positive DMSA study. Increased echogenicity/dysplasia, cortical thinning, atrophic kidney and/or abnormal corticomedullary differentiation defined a positive RUS. The sensitivity and specificity of RUS in identifying RS were calculated using DMSA scan as the gold standard.

RESULTS

A total of 144 patients had initial DMSA scans performed for UTI or VUR, with a RUS within 4 months, and no UTI between the 2 studies. Ninety-five of 144 (66%) had RS on DMSA and 49/144 (34%) did not. Patients with or without RS on DMSA were not different in gender (P = .073), age (P = .432), insurance (P = 1.000) or VUR grade (P = .132). Only 39/144 (27.1%) patients had positive RUS. The sensitivity of RUS for RS was 35.8% and the specificity was 89.8%, leading to an accuracy of 54.2% (95%CI; 45.7-62.5%, P = .999).

CONCLUSION

RUS demonstrated poor sensitivity for RS visualized on DMSA scan. This suggests that RUS is a poor screening test for RS or indicators of future renal scar. A normal ultrasound does not rule out RS or risk of future renal scar. Specificity of RUS was excellent.

Vesicoureteral Reflux and Renal Scarring in Infants After the First Febrile Urinary Tract Infection

Introduction

The objective of this research was to determine whether vesicoureteral reflux(VUR) was associated with evolution to renal scarring (RS) following a febrile urinary tract infection (UTI) in infants.

Materials and methods

Our research included 100 infants, ages up to 1 year with a first febrile UTI. The diagnostic was based on results of: laboratory findings, ultrasonography (USG), voiding cystourethrography (VCUG) and initial and control renal scintigraphy (DMSA renal scan) withtechnetium^99mTcsuccimer (dimercaptosuccinic acid), to assess the acute pyelonephritis (APN), VUR and RS.

Results

APN was proven with DMSA renal scan in 66 (66%) infants. Twenty-two infants (33.3%) had VUR in-group of patients with APN. On the control DMSA scan, performed 6 months after the first DMSA, the presence of RS was found in 18 (27.27%) infants. In infants with renal scars VUR were discovered in 9 of them (50%).

Conclusions

The pathogenesis of RS after febrile UTI in young children is multifactorial. Children with VUR have an increased risk for APN and RS. However, VUR is not the only precondition for RS. Creating a renal scarring cannot be imagined without the inflammatory process of the upper urinary system. Therefore, early detection and treatment of febrile UTIs in children and identify children at risk for RS are of primary importance.

First urinary tract infections in children: the role of the risk factors proposed by the Italian recommendations

AIM

In 2009, the Italian society for paediatric nephrology suggested the need for cystography, following a first febrile urinary tract infection (UTI), only in children at high risk for dilating vesicoureteral reflux or in the event of a second infection. The aim of this study was to evaluate the adequacy of the risk factors proposed by the Italian guidelines.

METHODS

Children aged 2-36 months, managed by 10 Italian hospitals between 2009 and 2013, with a first febrile UTI were retrospectively evaluated.

RESULTS

Four hundred and fourteen children were included: 51% female, mean age eight months. Escherichia coli was responsible of 84% UTIs. 269 children (65%) presented at least one risk factor, thus were further investigated: 44% had a reflux. The presence of a pathogen other than E. coli significantly predicted high-grade reflux, both in the univariate (Odd Ratio 2.52, 95% Confidence Interval 1.32-4.81, p < 0.005) and multivariate analysis (OR 2.74, 95% CI: 1.39-5.41, p: 0.003). 26/145 children (18%) with no risk factors experienced a second UTI, which prompted the execution of cystography, showing a dilating reflux in 11.

CONCLUSION

Among the risk factors proposed by the Italian guidelines, only the presence of a pathogen other than E. coli significantly predicted reflux. Cystography can be postponed in children with no risk factors.

Renal swelling indicates renal damage in infants with their first urinary tract infection

AIM

We used ultrasound to evaluate renal swelling as a predictor of acute and permanent renal damage in infants with their first urinary tract infection (UTI).

METHODS

The cohort at the Queen Silvia Children's Hospital, Gothenburg, Sweden, comprised 101 infants with their first UTI at a mean age of 3.9 ± 3.0 months. Acute and follow-up ultrasounds were carried out a few days and one month after treatment started, and a ^99m technetium dimercaptosuccinic acid (DMSA) scan was carried out after one month and after a year if the first scan was abnormal.

RESULTS

The acute ultrasounds showed that renal length and volume, calculated as standard deviation scores (SDS), were 1.39 ± 1.43 SDS and 1.30 ± 1.08 SDS. We found that 52% of the one-month DMSA scans and 25% of the one-year DMSA scans were abnormal. Renal length (p = 0.0026) and initial volume (p = 0.0005) on the ultrasound predicted acute renal damage at the one-month DMSA scan and initial renal length (p = 0.030) predicted permanent renal damage at the one-year DMSA scan.

CONCLUSION

Renal swelling was associated with renal damage. Although the diagnostic performance compared with the DMSA scan was weak, renal swelling may help clinicians to make decisions about further investigations and follow-ups of infants with UTIs.

Urinary C-megalin for screening of renal scarring in children after febrile urinary tract infection

BackgroundFebrile urinary tract infection (fUTI) in children may cause renal scarring. This study aimed to investigate the usefulness of urinary biomarkers for diagnosing renal scarring after fUTI.MethodsThirty-seven children (median age: 1.36 years, range: 0.52-12.17 years, 25 boys) with a history of fUTI, who underwent renal scintigraphy for 4 months or longer after the last episode of fUTI, were analyzed. A spot urine sample was obtained on the day of renal scintigraphy to measure levels of total protein, N-acetyl-β-D-glucosaminidase (NAG), β₂-microglobulin (BMG), neutrophil gelatinase-associated lipocalin (NGAL), liver-type fatty acid binding protein (L-FABP), and C-megalin (full-length megalin). Results were corrected for urinary creatinine (Cr) and compared between the group with renal scarring (n=23) and that without scarring (n=14). Urinary levels of C-megalin were also measured in healthy control subjects.ResultsNo significant differences in total protein, NGAL, L-FABP, NAG, and BMG levels were found between the groups. However, C-megalin levels were significantly higher in the renal scarring group than in the non-renal scarring group and healthy controls (P<0.001). A cutoff value of 6.5 pmol/nmol of urinary C-megalin/Cr yielded 73.9% of specificity and 92.9% of sensitivity.ConclusionUrinary C-megalin is useful for diagnosing renal scarring caused by fUTI.

Ultrasound is an effective and noninvasive method of evaluating renal swelling in infants with their first urinary tract infection

AIM

This study evaluated renal swelling in infants with a first urinary tract infection (UTI) by correlating renal length and volume with C-reactive protein (CRP) and body temperature.

METHODS

Ultrasounds were carried out on 104 infants at The Queen Silvia Children's Hospital, Gothenburg, Sweden - 58 boys (mean age 3.3 months) and 46 girls (mean age 4.8 months) - during the acute phase of their UTI. A second scan was performed on 94 of them 4 weeks later. Renal length and volume were computed to standard deviation scores (SDS).

RESULTS

The mean renal length and volume at the first ultrasound were 1.90 SDS (±1.54) and 1.67 SDS (±1.13) for the larger kidney and 0.86 SDS (±1.01) and 0.84 SDS (±0.90) for the smaller kidney. There was a significant decrease in renal length and volume between the two ultrasounds, with a mean difference of 0.96 SDS (±1.24) and 1.07 SDS (±1.10) for the larger kidney (p < 0.0001). The length and volume of the larger kidney correlated with CRP (p < 0.001), but only the renal length correlated with fever (p < 0.001).

CONCLUSION

Early ultrasound determined renal swelling in infants with a UTI and may be a valuable noninvasive way of identifying infants with renal parenchymal involvement.

Avoidance of voiding cystourethrography in infants younger than 3 months with Escherichia coli urinary tract infection and normal renal ultrasound

BACKGROUND AND OBJECTIVE

Urinary tract infection (UTI) represents the most common bacterial infection in infants, and its prevalence increases with the presence of high-grade vesicoureteral reflux (VUR). However, voiding cystourethrography (VCUG) is invasive, and its indication in infants <3 months is not yet defined. This study aims to investigate, in infants aged 0-3 months, if the presence of Escherichia coli versus non-E. coli bacteria and/or normal or abnormal renal ultrasound (US) could avoid the use of VCUG.

METHOD

One hundred and twenty-two infants with a first febrile UTI were enrolled. High-grade VUR was defined by the presence of VUR grade ≥III. The presence of high-grade VUR was recorded using VCUG, and correlated with the presence of E. coli/non-E. coli UTI and with the presence of normal/abnormal renal US. The Bayes theorem was used to calculate pretest and post-test probability.

RESULTS

The probability of high-grade VUR was 3% in the presence of urinary E. coli infection. Adding a normal renal US finding decreased this probability to 1%. However, in the presence of non-E. coli bacteria, the probability of high-grade VUR was 26%, and adding an abnormal US finding increased further this probability to 55%.

CONCLUSIONS

In infants aged 0-3 months with a first febrile UTI, the presence of E. coli and normal renal US findings allow to safely avoid VCUG. Performing VCUG only in infants with UTI secondary to non-E. coli bacteria and/or abnormal US would save many unnecessary invasive procedures, limit radiation exposure, with a very low risk (<1%) of missing a high-grade VUR.

Top-down approach is possible strategy for predicting breakthrough fUTIs and renal scars in infants

BACKGROUND

Acute-phase technetium-99 m dimercaptosuccinic acid (DMSA) scintigraphy is recommended for initial imaging in children with febrile urinary tract infection (fUTI). Recently, the importance of identifying patients at risk of recurrent fUTI (r-fUTI) has been emphasized. To clarify the effectiveness of DMSA scintigraphy for predicting r-fUTI in infants, we investigated the relationship between defects on DMSA scintigraphy and r-fUTI.

METHODS

Seventy-nine consecutive infants (male: female, 60:19) with fUTI were enrolled in this study. DMSA scintigraphy was performed in the acute phase, and patients with defect underwent voiding cystourethrography and chronic-phase (6 months later) DMSA scintigraphy. Patients were followed on continuous antibiotic prophylaxis (CAP).

RESULTS

Defects on acute-phase DMSA scintigraphy were observed in 32 children (40.5%) of 79. The mean follow-up observation period was 17.0 ± 10.1 months. Four patients had r-fUTI (5%). Two of them had defects on DMSA scintigraphy in both the acute phase and chronic phase, and had bilateral vesicoureteral reflux (VUR) grade IV. Two others had r-fUTI without defects on DMSA and did not have VUR. Twelve patients had defect on chronic-phase DMSA scintigraphy and four of them had no VUR.

CONCLUSIONS

The top-down approach is a possible method for predicting r-fUTI in infants and does not miss clinically significant VUR. Also, given that the prevalence of r-fUTI was 5% regardless of the presence of defects on acute-phase DMSA, then, in conjunction with genital hygiene and CAP, acute-phase DMSA might be unnecessary if chronic-phase DMSA is performed for all patients to detect renal scar.

Decreased Identification of Vesicoureteral Reflux: A Cautionary Tale

AIM

To find the trend in patient's visits to our centers for vesicoureteral reflux (VUR). We hypothesize that VUR diagnosis and hence possible nephropathy recognition may be diminishing because of changing practice patterns.

METHODS

Data were extracted from electronic medical records for new and follow-up patients aged 0-18 years with ICD-9/10 codes to correspond with VUR, VUR unilateral, VUR bilateral, and VUR with reflux nephropathy, as well as new patients with diagnoses of urinary tract infections (UTI) and pyelonephritis at two major pediatric centers from 2012 to 2015. Figures and statistics to reflect absolute clinic visits and annual trends were created with SPSS 2010. Linear regression was applied.

RESULTS

Annually, Le Bonheur Children's Hospital and Nationwide Children's Hospital experienced an average decrease of 13 and 17% in total VUR visits, and an average decrease of 22 and 27% in VUR nephropathy visits, respectively, for each institution. Patient visits for UTIs were reduced an average of 16% annually in both centers. Linear regression demonstrated that number of patients (patients/year ± SE) decreased annually 69 ± 19 (P = 0.02), 7 ± 2 (P = 0.02), and 67 ± 25 (P = 0.04) for VUR, VUR nephropathy, and UTI, respectively.

CONCLUSION

We conclude that the decreased number of VUR and VUR nephropathy cases identified in subspecialty clinics (Nephrology/Urology) at two major children's hospitals reflect a possible decreased identification of VUR. This trend may also be due to decreased referral of low grade cases of VUR. We cannot conclude that "undifferentiated UTI" referrals increased concomitantly to account for the decreased VUR as our data reflects a decreased trend in those visits as well. We suggest that clinicians following the American Academy of Pediatrics guidelines ensure that all UTI are accounted for and surveillance is appropriately escalated for recurrent UTI or abnormal imaging results.

Low serum 25-hydroxyvitamin D level and risk of urinary tract infection in infants

The aim of the study is to determine whether serum 25-hydroxyvitamin D (25(OH)D) deficiency in infants increased odds of urinary tract infection (UTI). A total of 238 infants including 132 patients experiencing a first episode of UTI and 106 controls, aged from 1 to 12 months, were enrolled. Serum 25(OH)D levels were tested through blood sampling. The serum 25(OH)D levels were significantly lower in cases with UTI than controls. The mean serum 25(OH)D levels were 29.09 ± 9.56 ng/mL in UTIs and 38.59 ± 12.41 ng/mL in controls (P < 0.001). Infants with acute pyelonephritis (APN) had lower serum 25(OH)D than those with lower UTI. The multivariate logistic regression analyses showed that serum 25(OH)D < 20 ng/mL (OR 5.619, 95% CI 1.469-21.484, P = 0.012) was positively related to an increased odds of UTI. Vitamin D supplementation (OR 0.298, 95% CI 0.150-0.591; P = 0.001) was associated with a decreased likelihood of UTI. Vitamin D deficiency in infants was associated with an increased odds of UTI. Interventional studies evaluating the role of vitamin D supplementation to reduce the burden of UTI are warranted.