Technetium-99m Dimercaptosuccinic Acid Research Articles

The physiological basis of renal nuclear medicine.

Renal physiology underpins renal nuclear medicine, both academic and clinical. Clearance, an important concept in renal physiology, comprises tissue uptake rate of tracer (tissue clearance), disappearance rate from plasma (plasma clearance), appearance rate in urine (urinary clearance) and disappearance rate from tissue. In clinical research, steady-state plasma clearances of para-amino-hippurate and inulin have been widely used to measure renal blood flow (RBF) and glomerular filtration rate (GFR), respectively. Routinely, GFR is measured at non-steady state as plasma clearance of a filtration agent, such as technetium-99m diethylenetriaminepentaacetic acid. Scaled to three-dimensional whole body metrics rather than body surface area, GFR in women is higher than in men but declines faster with age. Age-related decline is predominantly from nephron loss. Tubular function determines parenchymal transit time, which is important in renography, and the route of uptake of technetium-99m dimercaptosuccinic acid, which is via filtration. Resistance to flow is defined according to the pressure-flow relationship but in renography, only transit time can be measured, which, being equal to urine flow divided by collecting system volume, introduces further uncertainty because the volume is also unmeasurable. Tubuloglomerular feedback governs RBF and GFR, is regulated by the macula densa, mediated by adenosine and renin, and can be manipulated with proximal tubular sodium-glucose cotransporter-2 inhibitors. Other determinants of renal haemodynamics include prostaglandins, nitric oxide and dopamine, while protein meal and amino acid infusion are used to measure renal functional reserve. In conclusion, for measuring renal responses to exogenous agents, steady-state para-amino-hippurate and inulin clearances should be replaced with rubidium-82 and gallium-68 EDTA for measuring RBF and GFR.

Complete Remission of Renal Scarring in Follow-Up DMSA Renal Scintigraphy After Urinary Tract Infection.

Our study aimed to investigate the association between the characteristics of patients/images and complete remission of renal scarring shown in the first chronic phase Technetium-99m dimercaptosuccinic acid (DMSA) renal scintigraphy images in children with urinary tract infection (UTI). Fifty children, who underwent the chronic phase of DMSA scintigraphy more than twice following UTI diagnosis and had renal scarring in the first chronic phase DMSA renal scintigraphy, were enrolled. They were classified into 2 groups: with and without complete remission of renal scarring on the second chronic phase DMSA renal scintigraphy. Renal scarring was classified into 3 grades based on severity per the image findings. Seven cases had complete remission from renal scarring. There were significant differences in age and severity. Renal scarring might be completely reversed in young children without severe findings on DMSA renal scintigraphy. Additional chronic phase examination may aid in follow-up completion and patients' peace of mind.

Scinтigraphy in Children with Urinary Tract Dilatation (Antenatally Detected Hydronephrosis)

The causes of Antenatal Hydronephrosis/Urinary Tract Dilatation (ANH/UTD) vary from transient benign conditions-transit hydronephrosis, (resolves by birth or during infancy) to conditions that can significantly affect renal function. The outcome of depends on the underlying etiology, so it is very important to determine these causes. The definition and grading of ANH is based on the Anteroposterior Pelvic Diameter (APD) of the fetal renal pelvis. Antenatal management includes antenatal ultrasound monitoring, which is usually repeated every 4-6 weeks. It is recommended that the assessment of the severity of postnatal hydronephrosis is based on the APD of the renal pelvis. Extensive postnatal investigation was proposed to be limited to those with moderate or severe dilatation. Voiding cystourethrography and scintigraphy are usually preserved for children with postnatal APD <15 mm and/or abnormal kidney parenchyma, severe caliyx dilatation ureteral dilatation and bladder pathology. Diuretic renal scintigraphy is important in the postnatal evaluation of infants with ANH, particularly in distinguishing kidneys with poor drainage from nonobstructive hydronephrosis with good drainage. According to our diuretic renography results, we conclude that in the presence of partial or no drainage, the separate renal function may not be significantly impaired. The finding of poor renal emptying is significantly more common among children with increasing renal pelvis APD. Technetium 99m-dimercaptosuccinic acid renal scintigraphy (99mTc-DMSA) has been used in renal imaging to estimate the functional renal mass (damage to the kidney) and relative renal function, especially in pediatric patients. A statistically significant correlation between the degree of hydronephrosis (APD) and DMSA scan finding and between the degree of the VUR and DMSA scan finding was established. Other than VUR, CAKUT (pelvic ureteric junction obstruction, pyelon et ureter duplex, megaureter, posterior urethra valves) were not statistically correlated with pathological findings on the DMSA scan.

Diagnostic accuracy of shear wave elastography in evaluating renal fibrosis in children with chronic kidney disease: a comparative study with nuclear scan

BackgroundChronic kidney disease (CKD) is a significant health issue in pediatric patients due to fibrosis progression. Shear wave elastography (SWE) is a noninvasive technique used to assess fibrosis in CKD, but its efficacy needs to be better established. This study aimed to compare SWE with nuclear scan in assessing fibrosis in pediatric CKD patients.AimTo determine the area of scarring/fibrosis of each kidney using shear wave elastography in chronic kidney disease and compare it with technetium-99m dimercaptosuccinic acid (DMSA) results.MethodsA prospective study included 39 chronic kidney disease patients who underwent shear wave elastography and grayscale ultrasound. DMSA scans were performed to identify scar areas of the kidneys. Young modulus was recorded for each pole of both kidneys and compared with scar areas on DMSA. Thirty-nine age-matched controls underwent shear wave elastography to estimate the average elasticity value in the normal population.ResultsThirty-nine CKD patients underwent this study, with 10 females and 29 males. The median age was 6.5 years. The cutoff value of cortical thickness ≤ 10.2 predicted scar on DMSA with a sensitivity of 79% and a specificity of 77%. The cutoff value of elasticity value ≥ 5.57 kPa predicted scar on DMSA with a sensitivity of 87% and a specificity of 96%. Median SWE values were significantly higher with the scar on DMSA (12.6 kPa) compared to no scar on DMSA (4.1 kPa). The controls mean values and standard deviation were 2.42 kPa and 0.45 kPa, respectively.ConclusionsShear wave elastography has revealed that patients with chronic kidney disease exhibit higher values in the areas where scarring has occurred, compared to non-scarred areas. Fortunately, integrating shear wave elastography into routine ultrasonography assessments is a straightforward and painless process that requires no additional preparation from the patient. Not only is this method time efficient, but it also eliminates the need for potentially risky radiation exposure from radionuclide tests in the future.

Differentiation between normal and abnormal kidneys using 99mTc-DMSA SPECT with deep learning in paediatric patients

To investigate the feasibility of using deep learning (DL) to differentiate normal from abnormal (or scarred) kidneys using technetium-99m dimercaptosuccinic acid (99mTc-DMSA) single-photon-emission computed tomography (SPECT) in paediatric patients. Three hundred and one 99mTc-DMSA renal SPECT examinations were reviewed retrospectively. The 301 patients were split randomly into 261, 20, and 20 for training, validation, and testing data, respectively. The DL model was trained using three-dimensional (3D) SPECT images, two-dimensional (2D) maximum intensity projections (MIPs), and 2.5-dimensional (2.5D) MIPs (i.e., transverse, sagittal, and coronal views). Each DL model was trained to determine renal SPECT images into either normal or abnormal. Consensus reading results by two nuclear medicine physicians served as the reference standard. The DL model trained by 2.5D MIPs outperformed that trained by either 3D SPECT images or 2D MIPs. The accuracy, sensitivity, and specificity of the 2.5D model for the differentiation between normal and abnormal kidneys were 92.5%, 90% and 95%, respectively. The experimental results suggest that DL has the potential to differentiate normal from abnormal kidneys in children using 99mTc-DMSA SPECT imaging.

Ultrafast cadmium-zinc-telluride-based renal single-photon emission computed tomography: clinical validation

BackgroundOne of the main limitations of 99mtechnetium-dimercaptosuccinic acid (DMSA) scan is the long acquisition time.ObjectiveTo evaluate the feasibility of short DMSA scan acquisition times using a cadmium-zinc-telluride-based single-photon emission computed tomography (SPECT) system in children.Materials and methodsThe data of 27 children (median age: 4 years; 16 girls) who underwent DMSA SPECT were retrospectively analyzed. Both planar and SPECT DMSA were performed. SPECT images were analyzed using coronal-simulated planar two-dimensional images. A reduction in SPECT acquisition time was simulated to provide 4 series (SPECT-15 min, SPECT-10 min, SPECT-5 min and SPECT-2.5 min). A direct comparison of the planar and SPECT series was performed, including semi-quantification reproducibility, image quality (mean quality score on a scale of 0 to 2) and inter- and intra-observer reproducibility of the scintigraphic patterns.ResultsThe overall image quality score (± standard deviation) was 1.3 (± 0.6) for the planar data set, 1.6 (± 0.5) for the SPECT-15 min data set, 1.4 (± 0.5) for the SPECT-10 min data set, 1.0 (± 0.5) for the SPECT-5 min data set and 0.6 (± 0.6) for the SPECT-2.5 min data set. Median Kappa coefficients for inter-observer agreement between planar and SPECT images were greater than 0.83 for all series and all readers except one reader for the SPECT-2.5 min series (median Kappa coefficient = 0.77).ConclusionShortening SPECT acquisitions to 5 min is feasible with minimal impact on images in terms of quality and reproducibility.Graphical

Teknesyum-99m işaretli Dimerkaptosüksinik asit renal kortikal sintigrafi görüntülemede pelvik yerleşimli çapraz ektopik böbreği taklit eden deforme mesane aktivitesi

Technetium-99m dimercaptosuccinic acid (DMSA) scan was performed on a 32-year-old woman with 
 abdominal pain. A normal functioning slightly ptotic right kidney was seen on planar images. There 
 was no activity in the left renal region and a small fusiform activity was seen in the right pelvic area. 
 Pelvic computed tomography (CT) axial images revealed pre-vesical pelvic abscess pushing the 
 bladder posteriorly to the right side. On computed tomography images obtained after percutaneous 
 drainage it was concluded that the activity in the right pelvic area on Technetium-99m DMSA scan was 
 compatible with physiological activity in the bladder.

Low yield from imaging after non-E. coli urine tract infections in children treated in primary care and emergency department

BackgroundImaging is recommended for selected children following urinary tract infections (UTIs) to look for actionable structural abnormalities. Non-E. coli is considered high risk in many national guidelines, but evidence is...

Comparación entre el efecto de la nefrolitotomía percutánea miniaturizada vs. convencional en la función renal evaluada mediante gammagrafía renal con DMSA

Introduction and ObjectivesWe aimed to present a clinical study that compares standard and miniaturized percutaneous nephrolithotomy (PNL) effects on kidney function with scintigraphic imaging in primary kidney stone patients. Materials and MethodsOne hundred four patients were included in this prospective study between May 2014 and February 2017. Eligible patients were divided into two groups miniaturized PNL (mPNL) and standard PNL (sPNL) with matched-pair analysis (1:1 scenario). Technetium-99m Dimercaptosuccinic Acid cortical scintigraphy imaging was performed before and after the operation. ResultsThere were no differences between the two groups in terms of success rate (mPNL(63.5%) vs. sPNL(71.2%), p=0.403), serum creatinine, glomerular filtration rate, split renal functions pre- and postoperatively (p≥0.05). There was no relationship between the type of operation and new scar formation (p=0.780). The rates of serious complication (grades 3 and 4 according to modified Clavien-Dindo Classification) were higher in sPNL (p=0.034). Stone burden, duration of operation, hemoglobin drop, multiple access, blood transfusion, and angioembolization were higher in patients with scarred kidneys (p<0.001, p=0.008, p=0.004, p<0.001, p=0.003, p=0.001, respectively). In multivariate analysis, only multiple access was found statistically significant for predicting new scar formation (p<0.001, OR:24.28). ConclusionsMiniaturized and standard PNL are reliable and successful operations for treating large kidney stones. No significant difference was found between the operation types regarding a decrease in renal function.

Value of Cortical Scintigraphy with Technetium-99m Dimercaptosuccinic Acid (99mtc Dmsa) in Children with Acute Urinary Tract Infections

Value of Cortical Scintigraphy with Technetium-99m Dimercaptosuccinic Acid (99mtc Dmsa) in Children with Acute Urinary Tract Infections

Incidence of renal scarring on technetium-99m dimercaptosuccinic acid renal scintigraphy after acute pyelonephritis, acute focal bacterial nephritis, and renal abscess.

To evaluate the association between the incidence of renal scarring on technetium-99m dimercaptosuccinic acid (DMSA) renal scintigraphy and the severity of renal parenchymal infections, such as acute pyelonephritis (APN), acute focal bacterial nephritis (AFBN), and renal abscess, based on computed tomography (CT) diagnosis. Sixty-one children with renal parenchymal infections were included and classified into two groups: those with (renal scarring group) and without renal scarring (non-renal scarring group) on chronic-phase DMSA renal scintigraphy. The severity of renal parenchymal infection was classified into three grades using CT: APN, AFBN, and renal abscess as grades 1, 2, and 3, respectively. The severity of renal parenchymal infection, vesicoureteral reflux (VUR) grade, and intrarenal reflux occurrence during voiding cystourethrography (VCUG) were evaluated between the renal and non-renal scarring groups. Fisher's exact test and Mann-Whitney U test were used for statistical analysis. Renal scars were detected in 28 (45.9%) of the 61 patients. We found that 2/9 (22.2%), 18/41 (43.9%), and 8/11 (72.7%) patients with APN (grade 1), AFBN (grade 2), and renal abscess (grade 3) had renal scarring, respectively. There was a significant difference in the grade of severity of renal parenchymal infection between the renal (median = 2 [interquartile range, 2-3]) and non-renal (median = 2 [interquartile range, 2-2]) scarring groups (p = 0.023). There was a significant difference in the grade of VUR between the renal (median = 3 [interquartile range, 0-4]) and non-renal (median = 0 [interquartile range, 0-2]) scarring groups (p = 0.004). No significant difference in intrarenal reflux occurrence was observed between the renal (present/absent: 3/25) and non-renal (present/absent: 0/29) scarring groups (p = 0.112). Our results showed that pediatric patients with renal scarring on chronic-phase DMSA renal scintigraphy tended to have a more severe renal infection.

Comparison of the effect of miniaturized and standard percutaneous nephrolithotomy on renal function assessed with DMSA scintigraphy

Introduction and objectivesWe aimed to present a clinical study that compares standard and miniaturized percutaneous nephrolithotomy (PNL) effects on kidney function with scintigraphic imaging in primary kidney stone patients. Materials and methodsOne hundred four patients were included in this prospective study between May 2014 and February 2017. Eligible patients were divided into two groups miniaturized PNL (mPNL) and standard PNL (sPNL) with matched-pair analysis (1:1 scenario). Technetium-99m Dimercaptosuccinic Acid cortical scintigraphy imaging was performed before and after the operation. ResultsThere were no differences between the two groups in terms of success rate (mPNL (63.5%) vs. sPNL (71.2%), p=0.403), serum creatinine, glomerular filtration rate, split renal functions pre- and postoperatively (p≥0.05). There was no relationship between the type of operation and new scar formation (p=0.780). The rates of serious complication (grades 3 and 4 according to modified Clavien–Dindo Classification) were higher in sPNL (p=0.034). Stone burden, duration of operation, hemoglobin drop, multiple access, blood transfusion, and angioembolization were higher in patients with scarred kidneys (p<0.001, p=0.008, p=0.004, p<0.001, p=0.003, p=0.001, respectively). In multivariate analysis, only multiple access was found statistically significant for predicting new scar formation (p<0.001, OR: 24.28). ConclusionsMiniaturized and standard PNL are reliable and successful operations for treating large kidney stones. No significant difference was found between the operation types regarding a decrease in renal function.

Is technetium-99m dimercaptosuccinic acid renal scintigraphy available for predicting vesicoureteral reflux in children with first febrile urinary tract infection under the age of 24 months?

Vesicoureteral reflux (VUR) is a common complication after urinary tract infection (UTI) and can lead to irreversible renal scar. Voiding cystourethrogram is the most reliable technology to detect VUR and its severity, but it is restricted in children's examinations for various shortcomings. This study aimed to evaluate and compare the efficiency of Tc-99m DMSA renal scintigraphy and conventional ultrasonography (USG) in predicting VUR with the gold standard of cystourethrogram results. This retrospective study consisted of 285 first febrile UTI children under the age of 24 months who completed inflammatory indicator examinations, USG, Tc-99m DMSA renal scintigraphy and underwent cystourethrography after controlling infection with prophylactic antibiotics. The efficiency of Tc-99m DMSA renal scintigraphy and USG in predicting VUR was calculated and compared. Abnormal USG (40.23% vs. 21.72%, P = 0.001) and Tc-99m DMSA renal scintigraphy results (87.36% vs. 71.72%, P = 0.004) were more common in VUR children. The sensitivity of USG in predicting VUR was only 40.23%, whereas the sensitivity and negative predictive value of Tc-99m DMSA renal scintigraphy reached 87.63 and 83.58%, respectively. Tc-99m DMSA renal scintigraphy had a higher efficacy than USG in predicting high-grade reflux kidneys (73.87% vs. 33.33%; P < 0.001), but there was no significant difference in predicting low-grade reflux kidneys ( P = 0.703). Tc-99m DMSA renal scintigraphy had a significant higher efficiency in predicting VUR (a common cause of renal scarring, detected on DMSA) in first febrile urinary tract infection children under the age of 24 months as compared with USG, especially in high-grade reflux.

Usefulness of simulation in optimizing imaging settings for pediatric technetium-99m-dimercaptosuccinic acid single-photon emission computed tomography.

Technetium-99m (99mTc) dimercaptosuccinic acid (DMSA) single-photon emission computed tomography (SPECT) has been used to diagnose renal scarring. The Japanese Society of Nuclear Medicine recently revised the 'Consensus Guidelines for Pediatric Nuclear Medicine Examination.' In this study, we compared simulation data with actual data obtained using a pediatric phantom for 99mTc-DMSA examinations and evaluated the usefulness of simulations in determining the optimal acquisition conditions for SPECT images. A SPECT quality assurance (QA) phantom study produced images with a renal-to-background 99mTc ratio of 283:1 kBq/ml. The projection data for the simulation were simulated using the simulation of imaging nuclear detectors. To compare the actual measurements and simulations, recovery factors were used for the SPECT QA phantom for image quality assessment. Defect contrast and visual evaluation using Scheffe's method of pairwise comparison were used for the pediatric kidney phantom. The optimal imaging settings using a kidney phantom required an acquisition time of more than 8 min. The maximum difference in the recovery coefficient between the simulation and actual measurement using the SPECT QA phantom was 6%. We showed that an acquisition time of more than 8 min was necessary for DMSA-SPECT. In addition, phantom simulations were approximately equivalent to the actual measurement data and the adaptability of simulations was confirmed.

Neonatal Circumcision in Boys With Posterior Urethral Valves

Source: Harper L, Blanc T, Peycelon M, et al. Circumcision and risk of febrile urinary tract infection in boys with posterior urethral valves: result of the CIRCUP randomized trial. Eur Urol. 2022;81(1):64-72; doi:10.1016/j.eururo.2021.08.024Investigators from multiple institutions in France conducted a randomized controlled trial to assess the effect of circumcision on the risk of febrile urinary tract infection (fUTI) in infant boys with posterior urethral valves (PUV). Participants were male neonates 1-28 days old with PUV diagnosed by voiding cystogram, who were enrolled between 2012 and 2017 at 13 pediatric urology centers. Study patients were randomized to circumcision and antibiotic prophylaxis (CATB), or antibiotic prophylaxis alone (ATB) treatment groups. Circumcision was performed at the time of valve resection under general anesthesia. Antibiotic prophylaxis consisted of cefaclor 10 mg/kg/day for 1 month, followed by cotrimoxazole (15 mg/kg/day) until participants were 2 years old. A technetium-99m dimercaptosuccinic acid (DMSA) scan was performed when patients were 1-2 months and 2 years of age to evaluate renal damage. Study children were followed for 2 years. The primary outcome was fUTI, defined as culture-proven infection (≥103 bacteria/mL in catheterized specimens and ≥104 bacteria/mL for urine specimens obtained by suprapubic aspiration) with pyuria, in the presence of fever (>38.5° C) and signs of inflammation (leukocytosis, elevated C-reactive protein, and/or procalcitonin). The risk of fUTI in the 2 treatment groups was assessed using Kaplan-Meier analysis, and Cox regression was used to compare the risks. Adherence to antibiotic prophylaxis was assessed throughout the 2-year follow-up period and compared between groups. Evidence of increased renal damage between the initial and follow-up DMSA scans was determined and compared in those with and without fUTI with a chi-square test.Data were analyzed on 91 boys, including 49 randomized to CATB and 42 to the ATB group; the mean age at enrollment was 4.3 ± 5.0 and 7.1 ± 6.7 days, respectively, and mean age at valve resection was 5.2 ± 5.4 and 9.4 ± 11.6 days, respectively. A total of 64 (70%) children completed the entire 2-year follow-up period (33 in the CATB group and 31 in the ATB group). Overall, the risk of fUTI was 20% in the ATB group and 3% in those randomized to circumcision (hazard ratio [HR], 10.3; 95% CI, 1.3, 82.5). Adherence to the antibiotic prophylaxis regimen declined in participants during the study period but was not significantly different between treatment groups. At the time of the initial DMSA scan, 63% of children had abnormalities identified, and deterioration on DMSA scans was noted on 18% at follow-up, including 33% of those with a history of fUTI and 16% without fUTI (P = 0.29).The authors conclude circumcision decreased the risk of fUTI in boys born with PUV.Dr Sanchez-Kazi has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.The prevalence of fUTI is highest during the newborn period in boys with PUV.1 fUTI increases the risk of renal scarring, which can lead to chronic kidney disease. (See AAP Grand Rounds. 2019;42(5):53.)2 The current investigators evaluated whether circumcision reduces the risk of fUTI in boys with PUV. Although the results showed that CATB lowered the risk of fUTI, there was no difference between groups in the degree of kidney scarring as shown on the DMSA scans. Although it may be possible that this lack of significant change is explained by a lower number of participants, high attrition rate, variability in the radiographic interpretation of the DMSAs, short period of follow-up, or the inherent abnormal kidney parenchyma in boys with PUV due to possible dysplasia. However, the most likely explanation is that despite a substantial effect size (the rate of worsening DMSA scans was >2 times higher in those with fUTI than those without), there was insufficient power to detect a statistically significant difference in the outcomes.As stated in the accompanying editorial, circumcision reduced the occurrence of fUTI, but it did not decrease morbidity or mortality related to kidney scars.3 Steroid cream is currently used to manage phimosis in uncircumcised infants with fUTI.4 Will a retractable foreskin have the same advantage in infants with PUV?4 In boys with PUV however, neurogenic bladder and hydronephrosis are additional factors that significantly increase the probability of fUTI.1 In the most recent AAP Policy Statement on Circumcision in boys with a normal urinary tract, the committee left the decision-making to parents.5 The Canadian Urological Association also recommends early parental discussion of circumcision in the presence of an abnormal urinary tract including PUV, since the risk of fUTI is highest within the first 3 months of life.1,6 The results of the current study hopefully will contribute to more knowledgeable parental decision making.Neonatal circumcision in boys with posterior urethral valve decreases the risk of fUTI.

Hybrid Renal Cortical Imaging with Single Photon Emission Computerized Tomography/Computed Tomography in a Pediatric Patient with Severe Caudal Regression Syndrome

Caudal regression syndrome (CRS) or sacral agenesis is a rarely seen malformation with a varying degree of structural abnormalities, including multiorgan system dysfunctions, reported with higher incidence among children of mothers with diabetes, as in this case. Spinal anomalies can range from coccyx hemiagenesis to the total absence of lower lumbar vertebrae and sacrum in most severe cases. Herein, we have presented a 9-year-old patient with CRS who had renal failure. Technetium-99m dimercaptosuccinic acid renal scintigraphy revealed bilaterally non-functioning kidneys with no renal cortical uptake. Renal anomalies in CRS with vertebral, anorectal, cardiac, trachea-esophageal, renal, and limb anomalies association include one-sided renal agenesis, multicystic dysplastic kidneys, and ureter duplications.

Evaluation of platelet indices in children with renal scarring based on diagnostic accuracy criteria and Cohen's kappa.

Renal scarring is a significant complication in recurrent urinary tract infections (UTIs) in children that can lead to hypertension and end-stage renal disease. The present study evaluates whether platelet indices may be predictive of renal scarring. Sixty-nine patients aged 1-18 years with recurrent UTIs, whose medical records were reviewed to collect data on the presence of upper/lower UTIs and the results of scintigraphic investigations with 99m-technetium dimercaptosuccinic acid, were included in the study. The platelet, platelet indices (mean platelet volume [MPV]), platelet distribution width, plateletcrit, and C-reactive protein (CRP) values of the patients during UTI episodes were reviewed retrospectively. Mean platelet volume and CRP values were higher in the renal scarring group than in the non-renal scarring group (P < 0.001 and P = 0.003, respectively). Increases in MPV and CRP values were independent risk factors for renal scarring (OR = 5.781 [1.431-23.347] and OR = 1.922 [1.77-3.141], respectively). The sensitivity, specificity, positive and negative predictive values, and diagnostic odds ratio values of MPV at a cut-off of >8.2 fL for renal scarring discrimination were 62.5%, 88.89%, 75.00%, 81.63%, and 13.33 [1.35-3.83], respectively. The sensitivity, specificity, positive and negative predictive values, and diagnostic odds ratio values of CRP at a cut-off of 1.97 mg/L for renal scarring were 58.33%, 91.11%, 77.78%, 80.39%, and 14.35 [1.36-3.97], respectively. Both MPV and CRP can be used as predictive markers for renal scarring. While MPV had higher sensitivity, CRP had a higher specificity and diagnostic odds ratio in predicting renal scarring.

Demographic, clinical, and laboratory factors associated with renal parenchymal injury in Iranian children with acute pyelonephritis

BackgroundThe association between renal parenchyma changes on dimercaptosuccinic acid (DMSA) scans and demographic, clinical, and laboratory markers was assessed in pediatric patients with acute pyelonephritis.MethodsA retrospective study of 67 Iranian babies and children aged 1-month to 12-year with APN was conducted between 2012 and 2018. The presence of renal parenchymal involvement (RPI) during APN was determined using technetium-99m DMSA during the first 2 weeks of hospitalization. The association of DMSA results with demographic data, clinical features (hospitalization stay, fever temperature and duration), and laboratory parameters such as pathogen type, and hematological factors (ESR, CRP, BUN, Cr, Hb, and WBC) was evaluated.Results92.5% of children with an average age of 43.76 ± 5.2 months were girls. Twenty-four children (35.8%) did not have renal parenchymal injury (RPI), while 26 (38.8%) and 17 (25.4%) patients showed RPI in one and both kidneys, respectively. There was no significant association between RPI and mean ESR, CRP, BUN, and WBC. However, there were significant associations between RPI and higher mean levels of Cr, Hb, and BMI.ConclusionsLow BMI and Hb levels and increased Cr levels might be indicative of the presence of RPI in children with APN.

Vitamin D deficiency as a risk factor for renal scarring in recurrent urinary tract infections.

Renal scarring is a serious complication in recurrent urinary tract infections (UTIs). Vitamin D deficiency has also been reported to be a risk factor for UTIs although, to date, no association between vitamin D deficiency and renal scarring has yet been identified. In the present study, it was investigated whether vitamin D deficiency may be a risk factor for renal scarring in patients with recurrent UTIs. The study included patients between the ages of 1 and 18years who were admitted to the pediatric nephrology department of the center between November 1, 2018 and November 1, 2019 and who were diagnosed with recurrent UTIs. The medical records of the patients were reviewed for the collection of demographic data, vitamin D levels, ultrasonography results and scintigraphic investigations with 99m-technetium dimercaptosuccinic acid (99m Tc-DMSA). The patients were divided into two groups: those with and without renal scarring, diagnosed via 99m Tc-DMSA. The vitamin D levels and other parameters of the two groups were compared. Vitamin D deficiency (<20ng/mL) was observed in 73.9% of the patients without renal scarring, and in 94.1% of those with renal scarring (P = 0.015). A logistic regression analysis revealed vitamin D deficiency to be an independent risk factor for renal scarring in patients with recurrent UTIs (OR = 0.796 [0.691-0.917]). Vitamin D deficiency is found to be a risk factor for renal scarring in patients with recurrent UTIs. Vitamin D treatment may contribute to the prevention of renal scarring in patients with recurrent UTI.

Comparison of Renal Ultrasonography and Technetium 99-M Dimercaptosuccinic acid Renal Cortical Scintigraphy in Identifying Renal Parenchymal Defects in Febrile Urinary Tract Infection In Children Less than Five Years Age

Comparison of Renal Ultrasonography and Technetium 99-M Dimercaptosuccinic acid Renal Cortical Scintigraphy in Identifying Renal Parenchymal Defects in Febrile Urinary Tract Infection In Children Less than Five Years Age