Dimercaptosuccinic acid scintigraphy vs. ultrasound for renal parenchymal defects in children

SNMMI procedure standard/EANM practice guideline on pediatric [99mTc]Tc-DMSA renal cortical scintigraphy: an update

The Society of Nuclear Medicine and Molecular Imaging (SNMMI), founded in 1954, is an international scientific and professional organization with a purpose to promote the science, technology, and practical application of nuclear medicine. The European Association of Nuclear Medicine (EANM), founded in 1985, is a nonprofit professional medical association with a purpose to facilitate international communication among individuals in nuclear medicine pursuing clinical and academic excellence. Members of the SNMMI and EANM are physicians, technologists, and scientists who specialize in the research and practice of nuclear medicine. The SNMMI and EANM will periodically publish new guidelines for nuclear medicine practice to further advance the science of nuclear medicine and improve patient care. Existing standards/guidelines will be reviewed for revision or renewal, as appropriate. Each standard/guideline, representing a policy statement by the SNMMI/EANM, has undergone a thorough review, and represents an expert consensus. The SNMMI and EANM recognize that the safe and effective use of diagnostic nuclear medicine imaging requires specific training and skills, as described in each document. These standards/guidelines are educational resources designed to assist practitioners in providing appropriate nuclear medicine care for patients. They are consensus documents, and are not mandatory provisions or requirements of practice. They are not intended, nor should they be used, to establish a legal standard of care. For these reasons and those set forth below, the SNMMI and the EANM cautions against the use of these standards/guidelines in litigation procedures that call into question the clinical decisions of a practitioner. The ultimate judgment regarding the appropriateness and propriety of any specific procedure or course of action must be made by medical professionals, taking into account the unique context of each case. Thus, there is no implication that action differing from what is detailed in these standards/guidelines, on its own, is below the standard of care. On the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set forth in the standards/guidelines when, based on the reasonable judgment of the practitioner, such course of action is warranted based on the condition of the patient, limitations of available resources, or advances in knowledge or technology subsequent to publication of the standards/guidelines. Practicing medicine involves not only the science, but also the art of dealing with the prevention, detection, diagnosis, and treatment of disease. The variety and complexity of human conditions make it impossible for general guidelines to consistently allow for an accurate diagnosis to be reached or a specific treatment response to be predicted. Therefore, it should be recognized that adhering to these standards/guidelines does not ensure a successful outcome. All that should be expected is that a practitioner follows a reasonable course of action based on their level of training, the current landscape of knowledge, the resources at their disposal, and the needs/context of the particular patient being treated. The purpose of this document is to provide nuclear medicine physicians, radiologists, and other clinicians with guidelines for the recommendation, performance and interpretation of 99mTc-dimercaptosuccinic acid renal cortical scintigraphy ([99mTc] Tc-DMSA scintigraphy) in pediatric patients. These recommendations represent the expert opinions of experienced leaders in this field, and these recommendations are not all supported by a high level of evidence. Further studies are required to have evidence-based recommendations for the application of [99mTc] Tc-DMSA renal cortical scintigraphy in pediatrics. This guideline summarizes the views of the SNMMI Renal Cortical Scintigraphy in Children Working Group and the EANM Pediatrics Committee. It reflects recommendations for which the SNMMI and EANM cannot be held responsible. The recommendations should be taken into context of good practice of nuclear medicine and do not substitute for national and international legal or regulatory provisions.

Contemporary Management of Urinary Tract Infection in Children

Urinary tract infection (UTI) is common in children, and girls are at a significantly higher risk, as compared to boys, except in early infancy. Most cases are caused by Escherichia coli Collection of an uncontaminated urine specimen is essential for accurate diagnosis. Oral antibiotic therapy for 7 to 10 days is adequate for uncomplicated cases that respond well to the treatment. A renal ultrasound examination is advised in all young children with first febrile UTI and in older children with recurrent UTI. Most children with first febrile UTI do not need a voiding cystourethrogram; it may be considered after the first UTI in children with abnormal renal and bladder ultrasound examination or a UTI caused by atypical pathogen, complex clinical course, or known renal scarring. Long-term antibiotic prophylaxis is used selectively in high-risk patients. Few patients diagnosed with vesicoureteral reflux after a UTI need surgical correction. The most consequential long-term complication of acute pyelonephritis is renal scarring, which may increase the risk of hypertension or chronic kidney disease later in life. Treatment of acute pyelonephritis with an appropriate antibiotic within 48 hours of fever onset and prevention of recurrent UTI lowers the risk of renal scarring. Pathogens causing UTI are increasingly becoming resistant to commonly used antibiotics, and their indiscriminate use in doubtful cases of UTI must be discouraged.

Significance of nuclear medicine scan in comparison with diethylenetriamine pentaacetic acid and ultrasound imaging in diagnosing renal disorders: An observational study

The effectiveness of diethylenetriamine pentaacetic acid scan is regularly monitored for the assessment of any potential modifications in treatment responses or kidney functions in the pediatric population.This study attempts to compare the usefulness of diethylenetriamine pentaacetic acid and ultrasound imaging of renal disorders among paediatric patients.A retrospective observational study was conducted by enrolling 106 children. The demographic details such as: participant's age, gender, and the history of renal disease of each patient were recorded. Patients were administered radiopharmaceuticals in a fixed dose and were later subjected to computed tomography (CT) scan. The obtained data was analysed using descriptive statistics.Findings indicated increased sensitivity for CT (61.20%); whereas, a major decrease in specificity (23.68%) was observed. Comparison of Single-photon emission CT (SPECT) and CT findings revealed the increased sensitivity (90.90%) for ultrasound; whereas, there was a slight decrease in the specificity (40%) for SPECT. However, SPECT findings show 91% sensitivity among patients with 71.42% positive predictive value. Moreover, an increase in sensitivity for CT (61.20%), followed by a major decrease in specificity (23.68%) was observed.Ultrasonography has been proved to be the safest and the most effective method for the diagnosis and the treatment of most renal disorders, due to the higher predictive value of SPECT scans. It is thus suggested that patients with ureteral calculi should be diagnosed with renal scintigraphy and unenhanced helical computerized tomography.

The role of bladder function in the pathogenesis and treatment of urinary tract infections in toilet-trained children

Urinary tract infections (UTIs) are a common reason for referral to pediatric specialists and the risk profile of these children is influenced by age, sex, and underlying urinary tract abnormalities. UTIs in toilet-trained children represent a different entity than confirmed, febrile UTIs that occur in infants, impacted by suboptimal bladder habits, bladder dysfunction, constipation, or a combination of these factors. A comprehensive literature search was conducted using PubMed and MEDLINE and search terms included recurrent UTI, VUR, bladder and bowel dysfunction (BBD), constipation, lower urinary tract symptoms, and voiding dysfunction. Common presenting symptoms of UTI in children include fever (> 38 °C) with or without "traditional" lower urinary tract symptoms (LUTS) such as dysuria, malodorous urine, frequency, urgency, and incontinence. However, many infections in older children are afebrile episodes-consisting primarily of LUTS-which may or may not be confirmed with biochemical and/or microbiological evidence. Therefore, when evaluating toilet-trained children with recurrent UTIs, it is paramount to consider dysfunctional elimination as an underlying cause, diagnose, and treat it prior to indicating surgical options, even in the presence of VUR or other anatomical abnormalities. Although the impact of bladder function on the risk of infections is important, so is the accurate diagnosis and initial evaluation. This review article will focus on an often overlooked yet critical factor: the impact of bladder function, particularly for toilet-trained children, as well as the importance of implementing bladder training strategies, aggressive management of constipation, and pharmacological management as necessary.

In children with urinary tract infection reduced kidney length and vesicoureteric reflux predict abnormal DMSA scan

BACKGROUND

To evaluate sensitivity, specificity, and positive and negative predictive values (PPV and NPV, respectively) of renal ultrasonography (US) in predicting renal uptake defects or reduced renal function at Tc-99m dimercaptosuccinic acid (DMSA) scan (primary outcome). We also evaluated which factors could be associated with Tc-99m DMSA renal scan anomalies.

METHODS

We retrospectively included all the patients with vesico-ureteral reflux (VUR) undergoing the first Tc-99m DMSA renal scan within 3 months from the most recent renal US between 2016 and 2018.

RESULTS

Sensitivity, specificity, PPV, and NPV of US in predicting abnormal Tc-99m DMSA scan were 38.9%, 91.5%, 71.9%, and 72.9%, respectively. Different length between the kidneys, expressed as standard deviation score (SDS), showed an area under the receiver operating characteristic curve of 0.70 (95% CI, 0.60-0.80; p < 0.0001) when evaluated as predictor of abnormal Tc-99m DMSA scan. A different length between the two kidneys >1.11 SDS had 91.5% sensitivity and 57.6% specificity. At multivariate analysis, the factors with significantly increased odds ratio of abnormal Tc-99m DMSA scan were difference in length between two kidneys >1.11 SDS and dilated VUR.

CONCLUSIONS

The Tc-99m DMSA scan remains the gold standard to detect renal parenchymal anomalies. A different length between the kidneys >1.11 SDS and dilated VUR are predictors of abnormal Tc-99m DMSA renal scan.

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.

Serum neutrophil gelatinase-associated lipocalin for predicting acute pyelonephritis in infants with urinary tract infection

Introduction

Fever and elevated inflammatory markers have been used for diagnosis of acute pyelonephritis (APN) in infants with urinary tract infection (UTI).

The aim of the study was to compare the usefulness of serum neutrophil gelatinase-associated lipocalin (sNGAL) with inflammatory markers for predicting APN in infants with UTI.

Material and methods

The prospective study included 46 infants with a first episode of UTI, divided into two groups (APN 23, lower UTI 23), according to the DMSA scan results. The following laboratory tests were performed: sNGAL, PCT, CRP, WBC, and ESR.

Results

Significantly elevated levels of sNGAL, PCT, CRP, and ESR were observed in infants with APN compared to those with lower UTI. Higher sNGAL, CRP, and ESR values, presence of fever, and longer duration of fever before antibiotic treatment were associated with APN [odds ratio (OR) 1.02, 1.27, 1.03, 13.46, 2.12, respectively]. Receiver operating characteristic (ROC) analysis showed better diagnostic profiles for sNGAL, PCT, and CRP than for ESR for predicting APN [area under the curve (AUC) 0.808, 0.819, 0.841, and 0.750, respectively]. The appropriate cut-off values of sNGAL, PCT and CRP were 100.8 ng/ml, 0.15 ng/ml, 5.3 mg/dl (all sensitivity and specificity 82.6%), and that of ESR was 40 mm/h (sensitivity 78.3%, specificity 60.9%).

Conclusions

sNGAL shows similar usefulness as PCT and CRP for predicting APN in infants with UTI, the diagnostic value of ESR is smaller, and WBC is not useful at all. The presence of fever and longer duration of fever are important predictors of APN in infants with UTI.