Diagnostic performance of contrast-enhanced ultrasound for acute pyelonephritis in children

Contrast-Enhanced Ultrasound Follow-Up for Acute Pyelonephritis Patients

Contrast-enhanced ultrasound (CEUS) is increasingly used in clinical practice as the first diagnostic method in patients with suspected pyelonephritis rather than abdominal CT with contrast medium, especially in young subjects. We performed a retrospective analysis on patients in for whom a CEUS examination was utilized as a follow-up method after acute pyelonephritis as normal clinical practice. Through evaluating all patients, in terms duration between CEUS examination and normalization (healing) of the renal disease, we found that the mean duration is 25.9 days. Our ultrasound findings did not induce any therapeutic modifications, not even in the cases in which the examination was repeated several times. Therefore, setting up a CEUS follow-up examination after 25 days from the first diagnosis can reduce the number of repeated tests, benefitting patients and the healthcare system in terms of reducing costs.

Comparison of voiding vesicoureteral urosonography with fluoroscopic voiding cystourethrography in children with vesicoureteral reflux

Objective

To evaluate the value and compliance rate of voiding vesicoureteral urosonography in pediatric vesicoureteral reflux (VUR).

Methods

This is a retrospective study. A total of 80 children with high-risk VUR admitted to Children's Hospital affiliated to Capital Medical University from December 2018 to December 2020 were selected. All patients underwent voiding urosonography (VUS) and fluoroscopic voiding cystourethrography (VCUG). The sensitivity and compliance of voiding vesicoureteral urosonography were compared, and its application value was evaluated.

Results

A total of 160 PUUs were examined, and all cases were normal. Among them, 56 PUUs had reflux (35.00%, 56/160), 46 PUUs had reflux under both examination methods (28.75%, 46/160), and 10 PUUs were only detected under VUS (6.25%, 10/160). Thirty-four cases of VUR (42.50%, 34/80) were diagnosed by VUS, among which 15 cases were bilateral reflux and 4 cases were unilateral reflux. Twenty-five cases (35.00%, 25/80) were diagnosed by VCUG, among which 10 cases were bilateral regurgitation and five cases were unilateral regurgitation. No significant difference was observed in the detection rate of reflux between the two methods (P=0.432). A total of 146 PUUs were found to be consistent between the two methods (91.25%, 160), including 2 Grade-I reflux, 6 Grade-II reflux, 14 Grade-III reflux, 12 Grade-IV reflux, eight Grade-V reflux, and 104 without reflux, demonstrating SATISFACTORY consistency between the two groups (Kappa=0.885).

Conclusion

Voiding vesicoureteral urosonography has a high coincidence rate in the detection of vesicoureteral reflux in children.

Comparison of different ratios of cefoperazone/sulbactam in patients with pyelonephritis

Objective

To compare the clinical efficacy of different ratios of cefoperazone/sulbactam in the treatment of patients with pyelonephritis.

Methods

In this retrospective study clinical records of patients with pyelonephritis treated in Huzhou Traditional Chinese Medicine Hospital from July 2020 to July 2021 were collected,. It included 55 patients who received cefoperazone/sulbactam 2:1 treatment (Control group) and 57 patients who received 1 cefoperazone/sulbactam 1:1 treatment (Observation group). Clinical response, inflammatory reaction and bacterial clearance were compared between the two groups.

Results

The levels of C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-8 (IL-8) and leukocyte count (WBC) in the observation group were lower than those in the control group (P<0.05). The total efficacy of the Observation-group was 92.98%, higher than 80.00% of the control group (P<0.05). Fifty-eight strains of bacteria were isolated from the Control-group and 59 strains from the Observation-group. The bacterial clearance rates were 65.52% (38/58) and 83.05% (49/59), respectively. The differences were statistically significant (P<0.05).

Conclusions

The clinical efficacy of 1:1 ratio of cefoperazone/sulbactam in the treatment of patients with pyelonephritis was superior that of 2:1 ratio. This ratio allows to fully utilize the antibacterial effect of cefoperazone, with a significant decrease in inflammation markers and an improvement in bacterial clearance.

Contrast-enhanced ultrasound in detection and follow-up of focal renal infections in children

Objective:

Focal renal infections in children have to be diagnosed early in order to enable an appropriate antibiotic treatment. The purpose of this paper was to investigate the efficacy and clinical utility of intravenous renal contrast-enhanced ultrasound (CEUS) as an alternative imaging method for the diagnosis and follow-up of focal renal infections in children.

Methods:

Fourteen children aged from 6 months to 17 years (mean 6.5 years) in whom focal renal infection was suspected were included in this retrospective study. All data were obtained from medical and imaging records of the patients.

Results:

CEUS was performed for the diagnosis in all 14 children and then also for follow-up in seven children with renal abscess. In three children enhancement pattern was concordant with focal nephritis and in four children CEUS excluded focal renal infection and the diagnosis of pseudolesion was confirmed.

Conclusion:

Renal CEUS was proven to be an efficient and self-sufficient imaging in diagnosis and further follow-up of focal renal infections in children. CEUS patterns of focal renal infections are described as well as relevant CEUS enhancement patterns important for differential diagnosis. Renal abscess follow-up algorithm with CEUS is suggested.

Advances in knowledge:

All clinically relevant imaging data was obtained by CEUS and no other imaging was necessary for the diagnosis and follow-up.

Contrast-enhanced ultrasound of the kidneys: principles and potential applications

Contrast-enhanced ultrasound (CEUS) is an extension and an enhanced form of ultrasound that allows real-time evaluation of the various structures in different vascular phases. The last decade has witnessed a widespread expansion of CEUS applications beyond the liver. It has shown fair potential in kidneys and its diagnostic efficacy is comparable to CT and MRI. Ultrasound is the well-accepted screening modality for renal pathologies, however, it underperforms in the characterization of the renal masses. CEUS can be beneficial in such cases as it can help in the characterization of such incidental masses in the same sitting. It has an excellent safety profile with no risk of radiation or contract-related nephropathy. It can aid in the correct categorization of renal cysts into one of the Bosniak classes and has proven its worth especially in complex cysts or indeterminate renal masses (especially Bosniak Category IIF and III). Few studies also describe its potential role in solid masses and in differentiating benign from malignant masses. Other areas of interest include infections, infarctions, trauma, follow-up of local ablative procedures, and VUR. Through this review, the readers shall get an insight into the various applications of CEUS in kidneys, with imaging examples.

Pediatric kidney transplant recipients with and without underlying structural kidney disease have a comparable risk of hospitalization associated with urinary tract infections

INTRODUCTION

Urinary tract infections (UTIs) are a common and potentially serious kidney transplant complication. Pediatric kidney transplants are potentially at increased risk for UTIs when structural kidney disease is the underlying end-stage kidney disease (ESKD) etiology. The objective of this manuscript is to determine if children with structural kidney disorders are more prone to UTIs post kidney transplant.

MATERIALS AND METHODS

Hospitalizations for pediatric kidney transplant recipients were retrospectively reviewed over a 4-year period for UTIs in the diagnostic codes. The patient's age, sex, graft age, underlying diagnosis for cause of ESKD, symptoms at presentation, urinalysis results, and urine culture results were recorded. UTI rates, febrile UTI rates, and UTI rates in the 1st year post-transplant were compared between children with ESKD due to structural vs. non-structural kidney disease.

RESULTS

Overall, 62 of 145 pediatric patients with kidney transplants accounted for 182 hospitalizations for kidney transplant complications over the 4-year study period. UTIs were components of 34% of the hospitalizations. Overall, UTI rates, febrile UTI rates, and UTI rates for the 1st year post kidney transplant were comparable for children with vs. without structural ESKD etiologies.

CONCLUSION

Urinary tract infections are frequent components of hospitalizations for pediatric kidney transplant recipients. Children with and without structural kidney disease as an ESKD etiology have similar UTI rates indicating that UTI susceptibility is primarily due to the transplant process and/or medication regimens. UTIs represent a potentially modifiable risk factor for pediatric kidney transplant complications.

Contrast-enhanced voiding ultrasonography to detect intrarenal reflux in children: comparison with 99mTc-DMSA renal scans

Purpose

This study evaluated the diagnostic performance of contrast-enhanced voiding ultrasonography (CeVUS) for detecting intrarenal reflux (IRR) and the correlation between CeVUS-detected IRR sites and photon defect sites in acute ^99mTc-dimercaptosuccinic acid (DMSA) renal scans in pediatric patients.

Methods

Fifty-four kidneys from 27 patients (20 males and seven females; mean age, 5.6±4.1 months) who underwent CeVUS and acute DMSA renal scans for recurrent urinary tract infection (UTIs) or pyelonephritis were included. Pediatric experts compared the results of CeVUS with acute DMSA renal scans.

Results

Thirteen renal units (13/54, 24.1%) in 10 patients (nine males and one female; mean age, 6.3±3.7 months; age range, 0 to 13 months) showed vesicoureteral reflux and eight renal units (8/54, 14.8%) demonstrated IRR on CeVUS. Ten renal units in eight patients (six males and two females; mean age, 6.9±1.4 months; age range, 2 to 13 months) showed 19 photon defects on acute DMSA renal scans. Fifty-two renal units (96.3%) showed concordant results, and two renal units (3.7%) showed discordant results between CeVUS and acute DMSA renal scans. IRR accounted for 15/19 (78.9%) photon defects in eight renal units of seven patients using CeVUS. In a per-renal-unit analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CeVUS were 80%, 100%, 100%, 95.7%, and 96.3%, respectively.

Conclusion

CeVUS showed good performance in detecting IRR, and the IRR sites detected by CeVUS closely correlated with photon defect sites in acute DMSA scans. CeVUS may play an important role in managing patients with recurrent UTIs or pyelonephritis with reduced radiation exposure.

Contrast-enhanced ultrasound: a comprehensive review of safety in children

Contrast-enhanced ultrasound (CEUS) has been increasingly used in pediatric radiology practice worldwide. For nearly two decades, CEUS applications have been performed with the off-label use of gas-containing second-generation ultrasound contrast agents (UCAs). Since 2016, the United States Food and Drug Administration (FDA) has approved the UCA Lumason for three pediatric indications: the evaluation of focal liver lesions and echocardiography via intravenous administration and the assessment of vesicoureteral reflux via intravesical application (contrast-enhanced voiding urosonography, ceVUS). Prior to the FDA approval of Lumason, numerous studies with the use of second-generation UCAs had been conducted in adults and children. Comprehensive protocols for clinical safety evaluations have demonstrated the highly favorable safety profile of UCA for intravenous, intravesical and other intracavitary uses. The safety data on CEUS continue to accumulate as this imaging modality is increasingly utilized in clinical settings worldwide. As of August 2021, 57 pediatric-only original research studies encompassing a total of 4,518 children with 4,906 intravenous CEUS examinations had been published. As in adults, there were a few adverse events; the majority of these were non-serious, although very rarely serious anaphylactic reactions were reported. In the published pediatric-only intravenous CEUS studies included in our analysis, the overall incidence rate of serious adverse events was 0.22% (10/4,518) of children and 0.20% (10/4,906) of all CEUS examinations. Non-serious adverse events from the intravenous CEUS were observed in 1.20% (54/4,518) of children and 1.10% (54/4,906) of CEUS examinations. During the same time period, 31 studies with the intravesical use of UCA were conducted in 12,362 children. A few non-serious adverse events were encountered (0.31%; 38/12,362), but these were most likely attributable to the bladder catheterization rather than the UCA. Other developing clinical applications of UCA in children, including intracavitary and intralymphatic, are ongoing. To date, no serious adverse events have been reported with these applications. This article reviews the existing pediatric CEUS literature and provides an overview of safety-related information reported from UCA uses in children.

Clinical manifestations, laboratory markers, and renal ultrasonographic examinations in 1-month to 12-year-old Iranian children with pyelonephritis: a six-year cross-sectional retrospective study

BACKGROUND

Upper urinary tract infection (UTI) or pyelonephritis may increase the pathogenesis rate and risk of severe complications in children due to kidney atrophy.

OBJECTIVE

A set of clinical symptoms, laboratory markers, and ultrasound findings were assessed to achieve the early diagnosis and prognosis of pyelonephritis in hospitalized pediatrics.

METHODS

A cross-sectional study with 104 Iranian children (95 girls and 9 boys) aged 1 month to 12 years with acute pyelonephritis during 2012-2018 was conducted. The ultrasound examination of kidneys and urinary tract during hospitalization, the incidence of clinical symptoms, and laboratory markers in blood and urine were monitored to identify the best predictive factors of early diagnosis of this bacterial infection.

RESULTS

Three-fourth of the patients had one of the four clinical symptoms of abdominal pain, constipation, dysuria, and vomiting, while others were asymptomatic. A much frequency of pyuria (88.46%), Escherichia coli in urine (92.31%), leukocytosis (81.73%), and high ESR (> 10 mm/h, 92.30%) and CRP (> 10 mg/L, 82.82%) was observed. The kidney and urinary tract ultrasonography only in 32.7% of children revealed findings in favor of pyelonephritis (cystitis, ureteral stones, and hydronephrosis).

CONCLUSION

There was a high frequency of clinical signs and laboratory markers associated with pyelonephritis. Ultrasound alone was not an efficient tool to track febrile UTI as most patients presented normal sonography.

CT and MRI in Urinary Tract Infections: A Spectrum of Different Imaging Findings

There are many acute and chronic infections affecting the urinary tract including bacterial, fungal and viral infections. Urinary tract infections (UTIs) can present in many different patterns with variable degrees of severity varying from asymptomatic and uncomplicated forms to life threatening complicated infections. Cross-sectional imaging techniques—including both computed tomography (CT) and magnetic resonance imaging (MRI)—have become very important tools not only for evaluation of UTIs, but also for detection of associated complications. Selection of either CT or MRI in the UTI evaluation depends on several factors such as the presence of contraindication, experience, cost and availability. CT and MRI help in early detection and management of UTIs that reduce the prevalence and severity of complications. In this article we will present the radiologic findings at CT and MRI in different types of upper and lower UTIs including acute pyelonephritis, intrarenal and perinephric abscesses, pyonephrosis, chronic pyelonephritis, emphysematous UTIs, xanthogranulomatous pyelonephritis, tuberculosis (TB), bilharziasis, fungal infection, corynebacterium infection, ureteritis, cystitis, prostatitis, prostatic abscess and urethritis.