Our estimates of neonatal radiation exposure fall short of reality.

The purpose of this study is to evaluate radiation exposure in newborns undergoing imaging tests during the first 30 days of neonatal intensive care unit (NICU) hospitalization. A retrospective cohort study was conducted from November 2018 to April 2019 with newborns admitted to the NICU. Thermoluminescent dosimeters (TLD-100™) measured radiation emitted during imaging exams over 1 month, with a comparison between measured and estimated radiation. The cohort exhibited a median gestational age of 33.0 (31.0, 37.0) weeks, a median birth weight of 1840 (1272, 2748) g, and a median length of stay of 25.5 (11.7, 55.0) days. Eighty-four patients underwent 314 imaging tests, with an estimated radiation dose (ERD) per patient of 0.116 mSv and a measured radiation dose (MDR) of 0.158 mSv. ERD consistently underestimated MDR, with a mean difference of -0.043 mSv (-0.049 to -0.036) in the Bland-Altman analysis. The regression equation was as follows: difference MRD - ERD = -1.7 × (mean (MRD + ERD)) + 0.056. The mean estimated radiation dose per exam was 0.030 mSv, and the chest X-rays accounted for 63.26% of total exams. The median number of radiographic incidences per patient was 2 (1, 4), with 5 patients undergoing three or more exams in a single day. CONCLUSION: Radiation exposure in these newborns was underestimated, emphasizing the need for awareness regarding associated risks and strict criteria for requesting radiological exams. Lung ultrasound is a radiation-free and effective option in managing respiratory diseases in newborns, reducing the reliance on chest X-rays. WHAT IS KNOWN: • Radiation used in diagnostic exams is not risk-free. • Radiation risk is much higher in small Infants due to the exposure area and the prolonged expectance of life. WHAT IS NEW: • Radiation exposure is underestimated in the neonatal population. • The study found a mean radiation exposure in neonates about 5% of the mean annual dose in the general population.

Quality indicators in prolonged hemodialysis with regional citrate anticoagulation with the genius system: retrospective cohort of critical patients with acute kidney injury.

BACKGROUND: Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA. OBJECTIVE: To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system. METHODS: This is a retrospective cohort conducted in an intensive care unit. RESULTS: 53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%. CONCLUSION: The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.

Teenagers and young adults with a past of allogenic hematopoietic stem cell transplantation are at significant risk of chronic kidney disease.

BACKGROUND: Allogenic hematopoietic stem cell transplantation (aHSCT) remains the treatment of choice for some malignant hemopathies in children, albeit with the risk of long-term consequences, including chronic kidney disease (CKD). METHODS: In our single tertiary referral center, we retrospectively assessed the long-term renal outcome in a cohort of children and adolescents who had undergone aHSCT for malignant hemopathies between 2003 and 2017. We distinguished glomerular and tubular dysfunctions and assessed the accuracy of the most common formula(s) to estimate glomerular filtration rate (GFR) during standard clinical follow-up. RESULTS: Among the 166 patients who had received aHSCT, 61 underwent kidney functional assessment 1 to 10 years post-transplantation. Twenty-seven patients (44.3%) had a CKD with glomerular impairment, including 20 patients with a GFR < 90 mL/min/1.73 m2, and among these, 5 patients < 60 mL/min/1.73 m2. Patients with tubular signs had a significantly higher baseline GFR: 112 mL/min/1.73 m2 [100; 120] versus 102 [99.0; 112.5] for patients without kidney involvement, and 76 [61; 86] for patients with CKD (p < 0.01). Schwartz, CKiDU25, and EKFC formulas significantly overestimated mGFR, with a P30% ≤ 30%, which could lead to overlooking CKD diagnosis in this population. No patient reached kidney failure. CONCLUSIONS: In conclusion, our study shows that CKD represents an important long-term sequela for children and adolescents who undergo aHSCT for malignant hemopathies, either with glomerular dysfunction or with the more insidious tubular dysfunction which could potentially impact growth. These patients could benefit from specialized long-term nephrology follow-up. A higher resolution version of the Graphical abstract is available as Supplementary information.

Comparison of iohexol plasma clearance formulas vs. inulin urinary clearance for measuring glomerular filtration rate.

OBJECTIVES: The one-compartment iohexol plasma clearance has been proposed as a reliable alternative to renal inulin clearance. However, this method's performance depends on the formula used to calculate glomerular filtration rate (GFR). This study reports on performance comparisons between various mathematical formulas proposed for iohexol plasma clearance vs. inulin urinary clearance. METHODS: GFR was simultaneously determined by inulin and iohexol clearance in 144 participants (age: 10-84 years; glomerular filtration rate: 15-169 mL/min/1.73 m2). A retrospective cross-sectional study evaluated the performance of four formulas proposed to calculate plasma iohexol clearance (Brøchner-Mortensen, Fleming et al., Jødal-Brøchner-Mortensen, and Ng-Schwartz-Munoz). The performance of each formula was assessed using bias, precision (standard deviation of the bias), accuracy (percentage iohexol within 5, 10, and 15%), root mean square error, and concordance correlation coefficient vs. renal inulin clearance as reference. RESULTS: Regarding accuracy, there was no difference in root mean square error (RMSE), P5, P10, or P15 between the four formulas. The four concordance correlation coefficients (CCC) between the value from each formula and in-GFR were high and not significantly different. At in-GFR ≥90 mL/min/1.73 m2, Ng-Schwartz-Munoz formula performed slightly better than other formulas regarding median bias (-0.5; 95% CI [-3.0 to 2.0] and accuracy P15 (95.0; 95% CI [88.0-100.0]). CONCLUSIONS: The studied formulas were found equivalent in terms of precision and accuracy, but the Ng-Schwartz-Munoz formula improved the accuracy at higher levels of in-GFR.

Performances of creatinine-based glomerular filtration rate estimating equations in simultaneous pancreas-kidney transplant recipients: a single center cohort study.

Estimating glomerular filtration rate (GFR) is important for clinical management and research studies in simultaneous pancreas-kidney transplantation (SPK) recipients. No study has specifically investigated the reliability of recent creatinine-based GFR estimating equations in this singular population. We assessed the performances of CKD-EPI, MDRD, Schwartz-2009, Schwartz-Lyon, Lund-Malmo and Full Age Spectrum equations for estimating GFR after SPK. 126 patients were included. GFR was measured by a reference method (mGFR) one year after SPK and estimated with the different equations from a standardized measure of serum creatinine. Relative bias, precisions, 10% and 30% accuracies (P30) were used to determine equations reliability. Ages ranged from 29 to 58. Mean mGFR was 56.3 ± 13.3 [23.6-92.5] ml/min/1.73 m2 . In the whole population, P30 of the CKD-EPI and MDRD equations were 42% (38.0; 46.0) and 65% (61.5; 69) respectively. As compared to the other equations, the Schwartz-Lyon equation was significantly more accurate (P30 = 86.0% [83.5-88.0], P < 0.01) and less biased (1.13 [1.06-1.19], P < 0.01). Conclusions were similar whatever the age class (<40 or ≥40) and mGFR level (<60 or ≥60 ml/min/1.73 m2 ). This study suggests that the CKD-EPI and MDRD equations have poor performances in SPK recipients and that the Schwartz-Lyon equation is a reliable alternative.

Collaborative Brazilian pediatric renal transplant registry (CoBrazPed-RTx): A report from 2004 to 2018.

The Brazilian collaborative registry for pediatric renal transplantation began in 2004 as a multicenter initiative aimed at analyzing, reporting, and disseminating the results of pediatric renal transplantation in Brazil. Data from all pediatric renal transplants performed from January 2004 to May 2018 at the 13 participating centers were analyzed. A total of 2744 pediatric renal transplants were performed in the thirteen participating centers. The median age at transplantation was 12.2 years, with the majority being male recipients (56%). The main underlying diseases were CAKUT (40.5%) and glomerulopathy (28%). 1981 (72%) of the grafts were from deceased donors (DD). Graft survival at one year (censored by death) was 94% in the live donor group (LD) and 91% in the DD group (log-rank test P < 0.01). The patient's survival at one and 5 years was 97% and 95% for the LD group and 96% and 93% for the DD group (log-rank test P = 0.02). The graft loss rate was 19% (n = 517), more frequently caused by vascular thrombosis (n = 102) and chronic graft nephropathy (n = 90). DD recipients had 1.6 (1.0-2.2) times greater chance of death and 1.5 (1.2-1.8) times greater chance of graft loss compared to LD recipients. The mortality rate was 5.4% (n = 148), mainly due to infection (n = 69) and cardiovascular disease (n = 28). The results of this collaborative pediatric renal transplant record are comparable to other international registries, although we still have a high infection rate as a cause of death.

Trajectories and Predictors of Allograft Dysfunction after Renal Transplantation in Children.

BACKGROUND: The survival rates of renal transplant children are indeed on the rise, but it is still important to ensure that there is optimal renal function in these children in all their future growing years. The number of functioning nephrons and the graft ability to adapt to an increasing demand during body growth seem to be the most important factors for long-term allograft function. This study examined the long-term change in the glomerular filtration rate in a pediatric kidney transplant cohort and the importance of the recipient and donor ages in predicting transplant outcome. METHODS: Data on 67 renal transplant children who underwent 278 inulin-clearance measurements between 2000 and 2010 were examined. A longitudinal latent class model was used to identify renal function trajectories and classify the children. RESULTS: This model identified 3 trajectories of renal allograft function after pediatric kidney transplantation: 'low and decreasing', 'moderate and stable', and 'high and sharply decreasing'. The probability of belonging to the low and decreasing trajectory - that is, the poorer outcome - was lower in recipients of grafts from living versus deceased donor (adjusted OR (aOR) 0.02; p = 0.03). This probability increased with recipient age (aOR 1.20 per year of recipient ageing; p = 0.07) and donor-recipient age-difference (aOR 1.13 per additional year; p = 0.07). CONCLUSION: This study suggests that donation from living donors and from younger donors are favorable factors for long-term allograft function.

Estimating glomerular filtration rate for the full age spectrum from serum creatinine and cystatin C.

Background: We recently published and validated the new serum creatinine (Scr)-based full-age-spectrum equation (FAS crea ) for estimating the glomerular filtration rate (GFR) for healthy and kidney-diseased subjects of all ages. The equation was based on the concept of normalized Scr and shows equivalent to superior prediction performance to the currently recommended equations for children, adolescents, adults and older adults. Methods: Based on an evaluation of the serum cystatin C (ScysC) distribution, we defined normalization constants for ScysC ( Q cysC = 0.82 mg/L for ages <70 years and Q cysC = 0.95 mg/L for ages ≥70 years). By replacing Scr/ Q crea in the FAS crea equation with ScysC/ Q cysC , or with the average of both normalized biomarkers, we obtained new ScysC-based (FAS cysC ) and combined Scr-/ScysC-based FAS equations (FAS combi ). To validate the new FAS cysC and FAS combi we collected data on measured GFR, Scr, ScysC, age, gender, height and weight from 11 different cohorts including n = 6132 unique white subjects (368 children, aged ≤18 years, 4295 adults and 1469 older adults, aged ≥70 years). Results: In children and adolescents, the new FAS cysC equation showed significantly better performance [percentage of patients within 30% of mGFR (P30) = 86.1%] than the Caucasian Asian Paediatric Adult Cohort equation (P30 = 76.6%; P < 0.0001), or the ScysC-based Schwartz equation (P30 = 68.8%; P < 0.0001) and the FAS combi equation outperformed all equations with P30 = 92.1% (P < 0.0001). In adults, the FAS cysC equation (P30 = 82.6%) performed equally as well as the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI cysC ) (P30 = 80.4%) and the FAS combi equation (P30 = 89.9%) was also equal to the combined CKD-EPI equation (P30 = 88.2%). In older adults, FAS cysC was superior (P30 = 88.2%) to CKD-EPI cysC (P30 = 84.4%; P < 0.0001) and the FAS combi equation (P30 = 91.2%) showed significantly higher performance than the combined CKD-EPI equation (P30 = 85.6%) (P < 0.0001). Conclusion: The FAS equation is not only applicable to all ages, but also for all recommended renal biomarkers and their combinations.

Comparison of the Schwartz and CKD-EPI Equations for Estimating Glomerular Filtration Rate in Children, Adolescents, and Adults: A Retrospective Cross-Sectional Study.

BACKGROUND: Estimating kidney glomerular filtration rate (GFR) is of utmost importance in many clinical conditions. However, very few studies have evaluated the performance of GFR estimating equations over all ages and degrees of kidney impairment. We evaluated the reliability of two major equations for GFR estimation, the CKD-EPI and Schwartz equations, with urinary clearance of inulin as gold standard. METHODS AND FINDINGS: The study included 10,610 participants referred to the Renal and Metabolic Function Exploration Unit of Edouard Herriot Hospital (Lyon, France). GFR was measured by urinary inulin clearance (only first measurement kept for analysis) then estimated with isotope dilution mass spectrometry (IDMS)-traceable CKD-EPI and Schwartz equations. The participants' ages ranged from 3 to 90 y, and the measured GFRs from 3 to 160 ml/min/1.73 m2. A linear mixed-effects model was used to model the bias (mean ratio of estimated GFR to measured GFR). Equation reliability was also assessed using precision (interquartile range [IQR] of the ratio) and accuracy (percentage of estimated GFRs within the 10% [P10] and 30% [P30] limits above and below the measured GFR). In the whole sample, the mean ratio with the CKD-EPI equation was significantly higher than that with the Schwartz equation (1.17 [95% CI 1.16; 1.18] versus 1.08 [95% CI 1.07; 1.09], p < 0.001, t-test). At GFR values of 60-89 ml/min/1.73 m2, the mean ratios with the Schwartz equation were closer to 1 than the mean ratios with the CKD-EPI equation whatever the age class (1.02 [95% CI 1.01; 1.03] versus 1.15 [95% CI 1.13; 1.16], p < 0.001, t-test). In young adults (18-40 y), the Schwartz equation had a better precision and was also more accurate than the CKD-EPI equation at GFR values under 60 ml/min/1.73 m2 (IQR: 0.32 [95% CI 0.28; 0.33] versus 0.40 [95% CI 0.36; 0.44]; P30: 81.4 [95% CI 78.1; 84.7] versus 63.8 [95% CI 59.7; 68.0]) and also at GFR values of 60-89 ml/min/1.73 m2. In all patients aged ≥65 y, the CKD-EPI equation performed better than the Schwartz equation (IQR: 0.33 [95% CI 0.31; 0.34] versus 0.40 [95% CI 0.38; 0.41]; P30: 77.6 [95% CI 75.7; 79.5] versus 67.5 [95% CI 65.4; 69.7], respectively). In children and adolescents (2-17 y), the Schwartz equation was superior to the CKD-EPI equation (IQR: 0.23 [95% CI 0.21; 0.24] versus 0.33 [95% CI 0.31; 0.34]; P30: 88.6 [95% CI 86.7; 90.4] versus 29.4 [95% CI 26.8; 32.0]). This study is limited by its retrospective design, single-center setting with few non-white patients, and small number of patients with severe chronic kidney disease. CONCLUSIONS: The results from this study suggest that the Schwartz equation may be more reliable than the CKD-EPI equation for estimating GFR in children and adolescents and in adults with mild to moderate kidney impairment up to age 40 y.

An estimated glomerular filtration rate equation for the full age spectrum.

BACKGROUND: Glomerular filtration rate (GFR) is accepted as the best indicator of kidney function and is commonly estimated from serum creatinine (SCr)-based equations. Separate equations have been developed for children (Schwartz equation), younger and middle-age adults [Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation] and older adults [Berlin Initiative Study 1 (BIS1) equation], and these equations lack continuity with ageing. We developed and validated an equation for estimating the glomerular filtration rate that can be used across the full age spectrum (FAS). METHODS: The new FAS equation is based on normalized serum creatinine (SCr/Q), where Q is the median SCr from healthy populations to account for age and sex. Coefficients for the equation are mathematically obtained by requiring continuity during the paediatric-adult and adult-elderly transition. Research studies containing a total of 6870 healthy and kidney-diseased white individuals, including 735 children, <18 years of age, 4371 adults, between 18 and 70 years of age, and 1764 older adults, ≥70 years of age with measured GFR (inulin, iohexol and iothalamate clearance) and isotope dilution mass spectrometry-equivalent SCr, were used for the validation. Bias, precision and accuracy (P30) were evaluated. RESULTS: The FAS equation was less biased [-1.7 (95% CI -3.4, -0.2) versus 6.0 (4.5, 7.5)] and more accurate [87.5% (85.1, 89.9) versus 83.8% (81.1, 86.5)] than the Schwartz equation for children and adolescents; less biased [5.0 (4.5, 5.5) versus 6.3 (5.9, 6.8)] and as accurate [81.6% (80.4, 82.7) versus 81.9% (80.7, 83.0)] as the CKD-EPI equation for young and middle-age adults; and less biased [-1.1 (-1.6, -0.6) versus 5.6 (5.1, 6.2)] and more accurate [86.1% (84.4, 87.7) versus 81.8% (79.7, 84.0)] than CKD-EPI for older adults. CONCLUSIONS: The FAS equation has improved validity and continuity across the full age-spectrum and overcomes the problem of implausible eGFR changes in patients which would otherwise occur when switching between more age-specific equations.

Creatinine- versus cystatine C-based equations in assessing the renal function of candidates for liver transplantation with cirrhosis.

UNLABELLED: Renal dysfunction is frequent in liver cirrhosis and is a strong prognostic predictor of orthotopic liver transplantation (OLT) outcome. Therefore, an accurate evaluation of the glomerular filtration rate (GFR) is crucial in pre-OLT patients. However, in these patients plasma creatinine (Pcr) is inaccurate and the place of serum cystatine C (CystC) is still debated. New GFR-predicting equations, based on standardized assays of Pcr and/or CystC, have been recently recommended in the general population but their performance in cirrhosis patients has been rarely studied. We evaluated the performance of the recently published Chronic Kidney Disease Epidemiology Collaboration equations (CKD-EPI-Pcr, CKD-EPI-CystC, and CKD-EPI-Pcr-CystC) and the more classical ones (4- and 6-variable MDRD and Hoek formulas) in cirrhosis patients referred for renal evaluation before OLT. Inulin clearance was performed in 202 consecutive patients together with the determination of Pcr and CystC with assays traceable to primary reference materials. The performance of the GFR-predicting equations was evaluated according to ascites severity (no, moderate, or refractory) and to hepatic and renal dysfunctions (MELD score ≤ or >15 and KDOQI stages, respectively). In the whole population, CystC-based equations showed a better performance than Pcr-based ones (lower bias and higher 10% and 30% accuracies). CKD-EPI-CystC equation showed the best performance whatever the ascites severity and in presence of a significant renal dysfunction (GFR <60 mL/min/1.73 m(2)). CONCLUSION: Pcr-based GFR predicting equations are not reliable in pre-OLT patients even when an IDMS-traceable enzymatic Pcr assay is used. Whenever a CystC-assay traceable to primary reference materials is performed and when a true measurement of GFR is not possible, CystC-based equations, especially CKD-EPI-CystC, may be recommended to evaluate renal function and for KDOQI staging.

Renal function can be impaired in children with primary hyperoxaluria type 3.

BACKGROUND: Primary hyperoxaluria type 3 (PH3) is characterized by mutations in the 4-hydroxy-2-oxoglutarate aldolase (HOGA1) gene. PH3 patients are believed to present with a less severe phenotype than those with PH1 and PH2, but the clinical characteristics of PH3 patients have yet to be defined in sufficient detail. The aim of this study was to report our experience with PH3. METHODS: Genetic analysis of HOGA1 was performed in patients with a high clinical suspicion of PH after the presence of mutations in the alanine-glyoxylate aminotransferase gene had been ruled out. Clinical, biochemical and genetic data of the seven patients identified with HOGA1 mutations were subsequently retrospectively reviewed. RESULTS: Among the seven patients identified with HOGA1 mutations the median onset of clinical symptoms was 1.8 (range 0.4-9.8) years. Five patients initially presented with urolithiasis, and two other patients presented with urinary tract infection. All patients experienced persistent hyperoxaluria. Seven mutations were found in HOGA1, including two previously unreported ones, c.834 + 1G > T and c.3G > A. At last follow-up, two patients had impaired renal function based on estimated glomerular filtration rates (GFRs) of 77 and 83 mL/min per 1.73 m(2), respectively. CONCLUSIONS: We found that the GFR was significantly impaired in two of our seven patients with PH3 diagnosed during childhood. This finding is in contrast to the early-impaired renal function in PH1 and PH2 and appears to refute to preliminary reassuring data on renal function in PH3.

Can the height-independent Pottel eGFR equation be used as a screening tool for chronic kidney disease in children?

Determination of plasma creatinine (Pcr) should be associated to an estimation of glomerular filtration rate (eGFR). Pottel et al. established a height-independent equation, eGFR = 107.3/(Pcr/Q) where Q is the median of Pcr (Pottel-Belgium). The aims were to 1) determine a local height-independent equation (Pottel-Lyon), 2) evaluate the performance of these equations compared to the Schwartz 2009 and Schwartz-Lyon equations, and 3) evaluate the height-independent equations in laboratory routine. Therefore, 1) all first pediatric Pcr determination (December 2009-June 2011) were collected, and median of Pcr was determined for each 1-year age interval (Q-Lyon), 2) GFR was measured (mGFR) in 359 children (438 measures) and compared to eGFR, and 3) all first Pcr determination (January 2012-June 2013) were used to calculate eGFR with the Pottel-Lyon and the Pottel-Belgium equations. Pcr was determined by an IDMS-standardized enzymatic assay. In the population with a mGFR, the Pottel-Lyon and the Schwartz-Lyon showed the best performance (bias, P10 and P30). However, the performance in identifying patients with a mGFR < 75 mL/min/1.73 m(2) was similar for all the studied equations. CONCLUSION: The performance of the height-independent and dependent equations to identify mild renal dysfunction is similar. The height-independent Pottel equation could be proposed as an excellent screening tool for kidney disease when height information is not available. " WHAT IS KNOWN: " • Determination of plasma creatinine in children is rarely associated to an estimation of glomerular filtration rate due to the lack of height information. • Pottel et al. developed a height-independent equation (eGFR = 107.3/(Pcr/Q) where Q is the median of Pcr for each age class. " WHAT IS NEW: " • The performance of the height-independent (Pottel) or height-dependent (Schwartz) equations is similar to identify renal dysfunction (GFR < 75 mL/min/1.73 m (2) ) in children. • The height-independent Pottel equation could be an excellent screening tool for kidney disease in a general pediatric laboratory when height information is not available.

A new equation to estimate the glomerular filtration rate in children, adolescents and young adults.

BACKGROUND: A new estimated glomerular filtration rate (eGFR) equation, designed for isotope dilution mass spectrometry-standardized serum creatinine (Scr), is presented for use in children, adolescent boys and girls and young adults. METHODS: The new equation, eGFR = 107.3/(Scr/Q), is based on the concept of normalized Scr: Q is the normalization value and is considered as the Scr concentration for the average healthy child, adolescent or young adult of a specific height (L) and is modeled as a height-dependent polynomial of the fourth degree. RESULTS: The well-known Schwartz equation [eGFR = kL/Scr, k = 0.413 (Schwartz) or k = 0.373 (Schwartz-Lyon)] for children between 1 and 14 years can be seen as a special case of the new equation for which the Q-polynomial is simplified to a linear equation: Q = 0.0035 × L (cm). The new eGFR equation has been validated in a data set of n = 750 children, adolescents and young adults aged 10-25, against the true GFR (inulin method), and outperforms the selected (but most used) creatinine-based eGFR equations for children, mainly in the healthy GFR region. CONCLUSIONS: The new Q(height)-eGFR equation serves as an excellent screening tool for kidney disease in 1-25-year-old children, adolescents and young adults.

Pediatric kidney transplantation: outcomes with under and over 6-year-old donors.

OBJECTIVE: Kidney shortage for pediatric kidney transplantation (PKT) entails the need to use low-weight and age donors, despite the apprehension. The aim of this study was to analyze the pediatric deceased donor kidney transplantations (pDDKT) outcomes in the first year after the procedure, stratified by donor age. METHOD: Retrospective cohort of pDDKTs carried out between January 2013, and January 2018, at a PKT reference hospital in Southern Brazil. Donors were divided into group 1 (≤ 6 years), and group 2 (> 6 years); the analysis of the outcomes was carried out in the same period. RESULTS: There were 143 pDDKTs; 51 (35.66%) in group 1; and 92 (64.34%) in group 2. In both groups there were 17 graft losses (11.8%), with vascular thrombosis as the main cause (group 1: 5; group 2: 4). Among the complications, renal artery stenosis (RAS) with indication for angioplasty and stenting was more frequent in group 1 (7.8%; group 2: 2.2%). The 1-year Renal Transplant Recipients' and graft survival did not show significant differences between the groups, (p =  = 0.95). However, the Glomerular Filtration Rate analysis was higher in group 2, reaching, in the 12th month, 79.3 mL/min/1,73m2, compared to 69.7 mL/min/1,73m2 in group 1(p =  = 0.033). CONCLUSIONS: Small donors can be considered for pDDKTs, as long as there is an expert team to perform the transplantation.

GFR estimation in adolescents and young adults.

The performance of creatinine-based equations to obtain the estimated GFR in adolescents and young adults is poorly understood. We assessed creatinine-based GFR estimating equations in a cross-section of 751 adolescents and young adults (1054 measurements), using inulin clearance (measured GFR [mGFR]) as the reference method. We evaluated the following: Cockcroft-Gault, four-variable Modified Diet in Renal Disease, and the Chronic Kidney Disease Epidemiology Collaboration equations for adult participants, as well as the Schwartz 2009 and Schwartz-Lyon equations for pediatric age groups. Participants ranged in age from 10 to 26 years (mean 16.8 years); we divided the population into four groups according to age (10-12 years, 13-17 years, 18-21 years, and 21-25 years). Evaluation of the agreement between these formulas and mGFR (e.g., correlation, Bland-Altman plots, bias, and accuracy) showed that there was a good correlation between mGFR and both pediatric formulas in all age groups, whereas the adult formulas substantially overestimated mGFR. In conclusion, we recommend the use of pediatric equations to estimate GFR from childhood to early adulthood.

Average creatinine-urea clearance: revival of an old analytical technique?

Background: Creatinine-based equations such as the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) are recommended for estimating glomerular filtration rate (eGFR) in clinical practice, but have reduced performance in advanced stages of chronic kidney disease. However, only rarely studies have evaluated the performance of eGFR by measuring the average of the urinary clearances of creatinine and urea (mClUN-cr) compared with the eGFR equations. Methods: This cross-sectional study evaluated the usefulness of mClUN-cr in a population of 855 participants who performed a GFR measurement by urinary inulin clearance. The performance of mClUN-cr was compared with those of CKD-EPI 2009 and CKD-EPI 2021, considering three criteria: bias, precision and accuracy. Results: In the whole sample, the mClUN-cr performed similarly to CKD-EPI equations (2009 and 2021) [precision: 11.5 (95% CI 10.5; 12.5) vs 19.0 (95% CI 17.2; 20.1) and 19.1 (95% CI 17.4; 20.4), and accuracy P30: 97.0 (95% CI 95.8; 98.0) vs 82.0 (95% CI 79.2; 84.4) and 77.2 (95% CI 74.5; 80.0)]. The CKD-EPI equations (2009 and 2021) had the best performance when mGFR was >60 mL/min/1.73 m2. In contrast, the mClUN-cr performed better than others with lowest mGFR values, more noticeable when mGFR was <60 mL/min/1.73 m2. Conclusions: The study described the best performance of mClUN-cr at GFR levels below 60 mL/min/1.73 m2 and a satisfactory result in the overall cohort. The findings point to a role of this tool, especially for estimating GFR in chronic kidney disease patients in developing countries, when reference measurement of GFR is not available.

Epidemiological profile of congenital hypothyroidism at a southern Brazilian state.

Objective: To determine the incidence of congenital hypothyroidism (CH) over a 10-year period at the Reference Service in Neonatal Screening of the state of Rio Grande do Sul (RSNS-RS). Subjects and methods: Historical cohort study including all newborns screened for CH by the RSNS-RS from January 2008 until December 2017. Data of all newborns with neonatal TSH (neoTSH; heel prick test) values ≥ 9 mIU/L were collected. According to neoTSH values, the newborns were allocated into two groups: Group 1 (G1), comprising newborns with neoTSH ≥ 9 mIU/L and serum TSH (sTSH) < 10 mIU/L, and Group 2 (G2), comprising those with neoTSH ≥ 9 mIU/L and sTSH ≥ 10 mIU/L. Results: Of 1,043,565 newborns screened, 829 (0.08%) had neoTSH values ≥ 9 mIU/L. Of these, 284 (39.3%) had sTSH values < 10 mIU/L and were allocated to the G1 group, while 439 (60.7%) had sTSH ≥ 10 mIU/L and were allocated to the G2 group, and 106 (12.7%) were considered missing data. The overall incidence of CH was 42.1 per 100,000 newborns screened (95% confidence interval [CI] 38.5-45.7/100,000) or 1:2377 screened newborns. The sensibility and specificity of neoTSH ≥ 9 mIU/L were 97% and 11%; of neoTSH 12.6 mUI/L, 73% and 85% respectively. Conclusion: In this population, the incidence of permanent and transitory CH was 1:2377 screened newborns. The neoTSH cutoff value adopted during the study period showed excellent sensibility, which matters for a screening test.

Early renal abnormalities in children with postnatally diagnosed autosomal dominant polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) in children is often regarded as a benign condition. However, previous studies pointed out renal-related anomalies which may benefit from early appropriate treatments. This study was conducted to evaluate the prevalence and severity of early renal dysfunction in ADPKD children. METHODS: An extensive renal evaluation was performed in 52 consecutive ADPKD patients diagnosed either from prenatal screening or post-natal ultrasound (US) examination (54 % males, mean age 10 ± 4 years [1-17]). RESULTS: Three patients had both systolic (SBP) and diastolic (DBP) blood pressure above the 95th percentile, one patient had a "high normal" DBP, and one child was treated with an angiotensin-converting enzyme inhibitor (ACEI). The mean ± SD glomerular filtration rate (GFR ml/min per 1.73 m(2), inulin clearance) was 115 ± 26 [47-168] but six children (12 %) had a GFR < 90 and 11 (21 %) experienced hyperfiltration (GFR > 135). Microalbuminuria (2 < Ualb/Ucr ≤ 20 mg/mmol) was found in 25 patients and five had macroalbuminuria (>20 mg/mmol). CONCLUSIONS: Early renal manifestations are frequent in ADPKD children, including hypertension in 6 %, albuminuria in 58 %, and decreased GFR in 12 %. In conclusion, renal function in children with ADPKD should be regularly assessed in order to manage early renal dysfunction and even consider further therapeutic intervention.