Pediatric kidney care experience after the 2023 Turkey/Syria earthquake.

BACKGROUND/AIMS: Two earthquakes on February 6th, 2023 destroyed ten cities in Türkiye. We report our experience with pediatric victims during these catastrophes, with a focus on crush syndrome related-acute kidney injury (Crush-AKI) and death. METHOD: A web-based software was prepared. Patient demographics, time under rubble (TUR), admission laboratory data, dialysis, and kidney and overall outcomes were asked. RESULTS: 903 injured children (median age: 11.62 years) were evaluated. Mean TUR was 13 h (Interquartile range-IQR: 32.5), max 240 h). 31 of 32 patients with a TUR of >120 h survived. The patient who rescued after ten days survived.Two-thirds of the patients were given 50 mEq/L sodium-bicarbonate in 0.45% sodium-chloride solution on admission day. 58% of patients were given intravenous fluid (IVF) at a volume of 2000-3000 mL/m2 body surface area (BSA), 40% of 3000-4000 mL/m2 BSA, and only 2% of >4000 mL/m2 BSA. 425 patients had surgeries, 48 suffered from major bleeding. Amputations were recorded in 96 patients. Eighty-two and 66 patients required ventilator and inotropic support, respectively.Crush-AKI developed in 314 patients (36% of all patients). 189 patients were dialyzed. Age > 15 years, creatine phosphokinase (CK)≥20 950 U/L, TUR≥10 h, and the first-day IVF volume < 3000-4000 mL/m2 BSA were associated with Crush-AKI development. 22 deaths were recorded, 20 of 22 occurred in patients with Crush-AKI and within the first 4 days of admission. All patients admitted after 7 days survived. CONCLUSIONS: This is the most extensive pediatric kidney disaster data after an earthquake. Serum CK level was significantly associated with Crush-AKI at the levels of >20 950 U/L, but not with death. Adolescent age and initial IVF of less than 3000-4000 mL/m2 BSA were also asscoiated with Crush-AKI. Given that mildly injured victims can survive longer periods in the disaster field, we suggest uninterrupted rescue activity for at least 10 days.

Characteristics and predictors of chronic kidney disease in children with myelomeningocele: a nationwide cohort study.

BACKGROUND: Myelomeningocele (MMC) is highly prevalent in developing countries, and MMC-related neurogenic bladder is an important cause of childhood chronic kidney disease (CKD). This nationwide study aimed to evaluate demographic and clinical features of pediatric patients with MMC in Turkey and risk factors associated with CKD stage 5. METHODS: Data from children aged 0-19 years old, living with MMC in 2022, were retrospectively collected from 27 pediatric nephrology centers. Patients > 1 year of age without pre-existing kidney abnormalities were divided into five groups according to eGFR; CKD stages 1-5. Patients on dialysis, kidney transplant recipients, and those with eGFR < 15 ml/min/1.73 m2 but not on kidney replacement therapy at time of study constituted the CKD stage 5 group. RESULTS: A total of 911 (57.8% female) patients were enrolled, most of whom were expectantly managed. Stages 1-4 CKD were found in 34.3%, 4.2%, 4.1%, and 2.4%, respectively. CKD stage 5 was observed in 5.3% of patients at median 13 years old (range 2-18 years). Current age, age at first abnormal DMSA scan, moderate-to-severe trabeculated bladder on US and/or VCUG, and VUR history were independent risk factors for development of CKD stage 5 (OR 0.752; 95%; CI 0.658-0.859; p < 0.001; OR 1.187; 95% CI 1.031-1.367; p = 0.017; OR 10.031; 95% CI 2.210-45.544; p = 0.003; OR 2.722; 95% CI 1.215-6.102; p = 0.015, respectively). Only eight CKD stage 5 patients underwent surgery related to a hostile bladder between 1 and 15 years old. CONCLUSION: MMC-related CKD is common in childhood in Turkey. A proactive approach to neurogenic bladder management and early protective surgery in selected cases where conservative treatment has failed should be implemented to prevent progressive kidney failure in the pediatric MMC population in our country.

Complement gene mutations in children with C3 glomerulopathy: do they affect the response to mycophenolate mofetil?

BACKGROUND: C3 glomerulopathy (C3G) is a complement-mediated disease. Although genetic studies are not required for diagnosis, they are valuable for treatment planning and prognosis prediction. The aim of this study is to investigate the clinical phenotypes, kidney survival, and response to mycophenolate mofetil (MMF) treatment in pediatric C3G patients with and without mutations in complement-related genes. METHODS: Sixty pediatric C3G patients were included, divided into two groups based on complement-related gene mutations. Demographic and clinical-pathological findings, treatment modalities, and outcome data were compared, and Kaplan-Meier analysis was performed for kidney survival. RESULTS: Out of the 60 patients, 17 had mutations. The most common mutation was in the CFH gene (47%). The mean age at diagnosis was higher in the group with mutation (12.9 ± 3.6 vs. 11.2 ± 4.1 years, p = 0.039). While the patients without mutation most frequently presented with nephritic syndrome (44.2%), the mutation group was most likely to have asymptomatic urinary abnormalities (47.1%, p = 0.043). Serum parameters and histopathological characteristics were similar, but hypoalbuminemia was more common in patients without mutation. During 45-month follow-up,10 patients progressed to chronic kidney disease stage 5 (CKD5), with 4 having genetic mutation. The time to develop CKD5 was longer in the mutation group but not significant. MMF treatment had no effect on progression in either group. CONCLUSIONS: This study is the largest pediatric C3G study examining the relationship between genotype and phenotype. We showed that the mutation group often presented with asymptomatic urinary abnormalities, was diagnosed relatively late but was not different from the without mutation group in terms of MMF treatment response and kidney survival.

Clinical usefulness of anti-nuclear antibody in childhood: real-world experience at a tertiary care center : Usefulness of ANA in pediatric autoimmune diseases.

We evaluated the reasons for requesting anti-nuclear antibody (ANA) analysis in clinical practice at a tertiary center and the performance of ANA in pediatric autoimmune diseases. Patients under 18 years of age who underwent ANA testing for various symptoms between 2013 and 2017 were included. We retrieved data from medical records, including demographic and clinical characteristics, diagnoses, ANA results, titers, and staining patterns. The performance assessment tools were calculated according to the ANA titer for autoimmune diseases. Risk factors for autoimmune diseases in ANA-positive patients were evaluated using logistic regression analysis. Changes in ANA titer and seroconversion were evaluated using repeated ANA analyses. A total of 3812 patients underwent ANA. Medical records of 3320 patients were obtained. The rate of ANA positivity was 27.4%. ANA was requested most frequently because of musculoskeletal findings in 1355 patients (40.8%). Juvenile idiopathic arthritis (n = 174, 20.2%) was the most common diagnosis in ANA-positive patients, followed by systemic lupus erythematosus (n = 52, 6%). For autoimmune diseases, a titer of ≥ 1:100, a sensitivity of 40.1%, and a specificity of 77.1% were observed. At a titer ≥ 1:1000, the sensitivity and specificity were 24.1% and 89%, respectively. Homogeneous staining was an additional risk factor for autoimmune diseases in ANA-positive patients by multivariate logistic regression analysis (OR [95% CI]: 4.562 [3.076-6.766], p < 0.001).    Conclusion: Our results revealed that the performance of the ANA test in diagnosing autoimmune diseases in pediatric clinical practice was poor. Therefore, clinical findings should be carefully evaluated before ANA testing is performed. What is Known: • ANA can be detected in systemic autoimmune rheumatic diseases. • The diagnostic role of ANA is controversial, especially in childhood. What is New: • One in four patients who requested the ANA test had an autoimmune disease. • Less than half of patients with an autoimmune disease had ANA positivity.

A multicenter retrospective study of calcineurin inhibitors in nephrotic syndrome secondary to podocyte gene variants.

While 44-83% of children with steroid-resistant nephrotic syndrome (SRNS) without a proven genetic cause respond to treatment with a calcineurin inhibitor (CNI), current guidelines recommend against the use of immunosuppression in monogenic SRNS. This is despite existing evidence suggesting that remission with CNI treatment is possible and can improve prognosis in some cases of monogenic SRNS. Herein, our retrospective study assessed response frequency, predictors of response and kidney function outcomes among children with monogenic SRNS treated with a CNI for at least three months. Data from 203 cases (age 0-18 years) were collected from 37 pediatric nephrology centers. Variant pathogenicity was reviewed by a geneticist, and 122 patients with a pathogenic and 19 with a possible pathogenic genotype were included in the analysis. After six months of treatment and at last visit, 27.6% and 22.5% of all patients respectively, demonstrated partial or full response. Achievement of at least partial response at six months of treatment conferred a significant reduction in kidney failure risk at last follow-up compared to no response (hazard ratio [95% confidence interval] 0.25, [0.10-0.62]). Moreover, risk of kidney failure was significantly lower when only those with a follow-up longer than two years were considered (hazard ratio 0.35, [0.14-0.91]). Higher serum albumin level at CNI initiation was the only factor related to increased likelihood of significant remission at six months (odds ratio [95% confidence interval] 1.16, [1.08-1.24]). Thus, our findings justify a treatment trial with a CNI also in children with monogenic SRNS.

Evaluation of the Claria sharesource system from the perspectives of patient/caregiver, physician, and nurse in children undergoing automated peritoneal dialysis.

BACKGROUND: Automated peritoneal dialysis (APD) is increasingly preferred worldwide. By using a software application (Homechoice with Claria sharesource system (CSS)) with a mod-M added to the APD device, details of the home dialysis treatment become visible for PD nurses and physicians, allowing for close supervision. We aimed to evaluate the perceptions of patients/caregivers, PD nurses, and physicians about the advantages and disadvantages of CSS. METHODS: Three different web-based questionnaires for patients/caregivers, nurses, and physicians were sent to 15 pediatric nephrology centers with more than 1 year of experience with CSS. RESULTS: Respective questionnaires were answered by 30 patients/caregivers, 22 pediatric nephrologists, and 15 PD nurses. Most of the nurses and physicians (87% and 73%) reported that CSS improved patient monitoring. A total of 73% of nurses suggested that CCS is not well known by physicians, while half of them reported reviewing CSS data for all patients every morning. Sixty-eight percent of physicians thought that CSS helps save time for both patients/caregivers and healthcare providers by reducing visits. However, only 20% of patients/caregivers reported reduced hospital visits. A total of 90% of patients/caregivers reported that being under constant monitoring made them feel safe, and 83% stated that the patient's sleep quality improved. CONCLUSIONS: A remote monitoring APD system, CSS, can be successfully applied with children for increased adherence to dialysis prescription by giving shared responsibility and may help increase the patient's quality of life. This platform is more commonly used by nurses than physicians. Its potential benefits should be evaluated in further well-designed clinical studies with larger patient groups. A higher resolution version of the Graphical abstract is available as Supplementary information.

Comparison of infants and children with urolithiasis: a large case series.

We evaluated the demographic features, etiologic risk factors, treatment strategies, and outcome of the infants and children with urolithiasis (UL). A retrospective multicenter study was conducted including 23 Pediatric Nephrology centers in Turkey. The medical records of 2513 children with UL were reviewed. One thousand, three hundred and four boys and 1209 girls (1.1:1) were reported. The mean age at diagnosis was 39.5 ± 35 months (0.4-231 months), and 1262 patients (50.2%) were in the first year of life (infants). Most of the cases with infantile UL were diagnosed incidentally. Microlithiasis (< 3 mm) was found in 794 patients (31.6%), and 64.5% of the patients with microlithiasis were infants. Stones were located in the pelvis-calyces in 63.2% (n: 1530) of the cases. The most common stone type was calcium oxalate (64.6%). Hypocitraturia was the most common metabolic risk factor (MRF) in children older than 12 months, but in infancy, hypercalciuria was more common. Fifty-five percent of the patients had received at least one medical treatment, mostly potassium citrate. At the end of a year's follow-up, most of the patients with microlithiasis (85%) showed spontaneous remission. The rate of spontaneous stone resolution in infants was higher than in children. Spontaneous remission rate was higher in cases with MRF ( - ) stones than in MRF ( +) stones. However, remission rate with medical treatment was higher in cases with MRF ( +) stones. This study represents the results of a large series of infants and children with UL and showed that there are several differences such as underlying metabolic and anatomic abnormalities, clinical course, and stone remission rates between infants and children with urinary stone disease.

A nationwide retrospective study in Turkish children with nephrocalcinosis.

BACKGROUND: Nephrocalcinosis (NC) is defined as calcium deposition in the kidney parenchyma and tubules. This study aims to determine the etiology, risk factors, and follow-up results of patients with NC in Turkey. METHODS: Patients diagnosed with NC in the pediatric nephrology Department Units of 19 centers from all geographical regions of Turkey over a 10-year period (2010-2019) were included in the study. The medical records from the centers were reviewed and demographic data, admission complaints, medical history, systemic and genetic disorders, risk factors for NC, treatment details, and presence of NC after one-year follow-up, were recorded retrospectively. RESULTS: The study sample included 195 patients (88 females, 107 males). The mean age at diagnosis was 39.44 ± 47.25 (0.5-208) months; 82/190 patients (43.2%) were diagnosed incidentally; 46/195 patients (23.6%) had an underlying disease; idiopathic hypercalciuria was detected in 75/195 (38.4%) patients. The most common systemic diseases were distal renal tubular acidosis in 11/46 patients (23.9%), primary hyperoxaluria in 9/46 patients (19.6%) and Bartter syndrome in 7/46 patients (15.3%). After one year of follow-up, NC resolved in 56/159 patients (35.2%) and they all did not have an underlying systemic disease. DISCUSSION: The most common presentation of NC was incidental. Distal renal tubular acidosis and primary hyperoxaluria were the main systemic diseases leading to NC, while hypercalciuria was the most common metabolic risk factor. Nephrocalcinosis was found to remain in most of the patients at a one-year follow-up. It may resolve particularly in patients with no underlying systemic disease.

Aetiology, course and treatment of acute tubulointerstitial nephritis in paediatric patients: a cross-sectional web-based survey.

BACKGROUND: Acute tubulointerstitial nephritis (TIN) is a significant cause of acute renal failure in paediatric and adult patients. There are no large paediatric series focusing on the aetiology, treatment and courses of acute TIN. PATIENTS, DESIGN AND SETTING: We collected retrospective clinical data from paediatric patients with acute biopsy-proven TIN by means of an online survey. Members of four professional societies were invited to participate. RESULTS: Thirty-nine physicians from 18 countries responded. 171 patients with acute TIN were included (54% female, median age 12 years). The most frequent causes were tubulointerstitial nephritis and uveitis syndrome in 31% and drug-induced TIN in 30% (the majority of these caused by non-steroidal anti-inflammatory drugs). In 28% of patients, no initiating noxae were identified (idiopathic TIN). Median estimated glomerular filtration rate (eGFR) rose significantly from 31 at time of renal biopsy to 86 mL/min/1.73 m2 3-6 months later (p<0.001). After 3-6 months, eGFR normalised in 41% of patients (eGFR ≥90 mL/min/1.73 m2), with only 3% having severe or end-stage impairment of renal function (<30 mL/min/1.73 m2). 80% of patients received corticosteroid therapy. Median eGFR after 3-6 months did not differ between steroid-treated and steroid-untreated patients. Other immunosuppressants were used in 18% (n=31) of patients, 21 of whom received mycophenolate mofetil. CONCLUSIONS: Despite different aetiologies, acute paediatric TIN had a favourable outcome overall with 88% of patients showing no or mild impairment of eGFR after 3-6 months. Prospective randomised controlled trials are needed to evaluate the efficacy of glucocorticoid treatment in paediatric patients with acute TIN.

Erythropoietin Resistance Index and the Affecting Factors in Children with Peritoneal Dialysis.

BACKGROUND: Erythropoiesis-stimulating agents (ESAs) are used to treat anemia in CKD. Erythropoietin resistance index (ERI) is a useful tool used to evaluate the response to ESAs. In this study, we aimed to evaluate the causes of high ERI in children undergoing peritoneal dialysis (PD). METHOD: Patients who had been on PD for at least 1 year were included in this retrospective study. Demographic characteristics, residual kidney function (RKF), adequacy of dialysis, peritoneal glucose exposure, the number and reason for hospitalization, and medications were recorded. Anemia and laboratory parameters that may affect anemia were noted by taking the average of laboratory values in the last follow-up year (time-averaged). The weekly ESA dose was proportioned to the annual average hemoglobin value and body weight to calculate the ERI in terms of U/kg/week/g/dL. RESULTS: A total of 100 patients were included in the study. The mean ESA dose and ERI value were 119.8 ± 66.22 U/kg/week and 13.01 ± 7.52 U/kg/week/g/dL, respectively. It was determined that the patients <5 years of age have very high ERI value, and these patients need 2 times more ESA than those >10 years of age. Absence of RKF, large number of hospitalization, and ACEI use were also found to affect the ERI value negatively. CONCLUSION: We demonstrate that the most important factor affecting ERI value is young age. We also reveal that absence of RKF, large number of hospitalization, and ACEI use are also important variables affecting the ERI value.

Magnesium levels in children with chronic kidney disease stages 1-3 / Niveles de magnesio en niños con enfermedad renal crónica estadios 1-3

ABSTRACT Objective: The objective of this study was to assess serum and urinary magnesium levels in children who have chronic kidney disease stages 1-3. Methods: Eighty-seven patients who were followed at pediatric nephrology department for chronic kidney disease were included in the study. Age, gender, magnesium, dietary magnesium, and creatinine levels, and fractionated magnesium excretion for all cases were recorded. Patients with chronic kidney disease and control groups were compared in terms of these data. Results: Thirty-nine cases with chronic kidney disease were stage 1, 26 were stage 2, and 22 were stage 3. Average age was 9.9 ± 2.8 years in the control group and 10.2 ± 2.6 years in the chronic kidney disease group. The serum magnesium levels were significantly higher in the stage 3 group than in the control group (P<0.001). Also, in stage 3, fractionated magnesium excretion levels were higher compared to the control group (P<0.001). Conclusion: In chronic kidney disease with advancing renal failure, hypermagnesemia is frequently seen. Serum magnesium levels should be measured periodically in all the children with chronic kidney disease stage 3 to investigate magnesium abnormalities and assess clinical results.

RESUMEN Objetivo: El objetivo de este estudio fue evaluar los niveles de magnesio sérico y urinario en niños con enfermedad renal crónica en estadios 1-3. Material y métodos: Se incluyeron en el estudio 87 pacientes que tuvieron seguimiento en el servicio de nefrología pediátrica por enfermedad renal crónica. Se registraron los siguientes datos: edad, sexo, niveles de magnesio, ingesta de alimentos con magnesio, y creatinina, así como también la excreción fraccionada de magnesio para todos estos casos. Sobre la base de dichos datos, se compararon los pacientes con enfermedad renal crónica y los grupos de control. Resultados: De los 87 casos de enfermedad renal crónica, 39 se hallaban en estadio 1; 26, en estadio 2, y 22, en estadio 3. La edad promedio fue de 9,9 ± 2,8 años en el grupo control y de 10,2 ± 2,6 años en el grupo de enfermedad renal crónica. Los niveles de magnesio en suero fueron significativamente más altos en el grupo del estadio 3 que en el grupo control (p <0,001). Además, en el estadio 3, los niveles de excreción fraccionada de magnesio fueron más altos en comparación con el grupo control (p <0,001). Conclusión: En la enfermedad renal crónica con insuficiencia renal avanzada, se observa con frecuencia una hipermagnesemia. Los niveles séricos de magnesio deben medirse periódicamente en todos los niños con enfermedad renal crónica en estadio 3 para investigar las anomalías del magnesio y evaluar los resultados clínicos.

Do children with solitary or hypofunctioning kidney have the same prevalence for masked hypertension?

BACKGROUND: Having a low nephron number is a well-known risk factor for hypertension. There is an inverse relationship between the filtration surface area and systemic hypertension. A significant percentage of masked hypertension can be detected in children with nephron loss by ambulatory blood pressure monitoring (ABPM). METHODS: We prospectively investigated ABPM results of children having reduced kidney mass with normal office blood pressures (BPs) and kidney function. Forty-three children with congenital solitary kidney (group 1), 11 children with acquired solitary kidney (group 2), and 76 children with hypofunctioning kidney (group 3) were compared with age, gender, and BMI-matched healthy control group (group 4). The dietary salt intake of 76 patients was evaluated as salt equivalent (g/day). The primary endpoint was change from baseline in mean 24-h ABPM variables and the proportion of patients with masked hypertension when assessed by ABPM. RESULTS: The masked hypertension ratio of all patients was 12.3% when assessed with ABPM. Night hypertension was significantly higher in all patient groups than in the control group (p = 0.01). Diastolic BP loads of groups 1 and 3 were higher than in controls (p = 0.024). Systolic BP loads were higher only in group 1 than in the control group (p = 0.003). The dietary salt equivalent of patients in group 1 correlated positively with 24-h SBP and mean arterial pressure (MAP) values. Patients with excessive dietary salt intake in group 1 had a significantly higher diastolic BP load than those without excessive salt intake in group 1 (p = 0.002). CONCLUSIONS: Masked hypertension can be seen in children with a solitary kidney or when one of the kidneys is hypofunctioning. Systolic BP loads are higher in children with congenital solitary kidney, and salt intake correlates with systolic BP profiles especially in those. Our results suggest that being born with a congenital solitary kidney increases predisposition to hypertension and salt sensitivity.

Patient Outcomes of Henoch-Schönlein Purpura Nephritis According to the New Semiquantitative Classification.

Background: A new semiquantitative classification (SQC) for pediatric Henoch-Schönlein nephritis (HSN) was defined recently. The outcomes of pediatric HSN patients are reevaluated according to the new classification. Methods: Primary kidney biopsies from 80 HSN patients were scored using the new SQC. The International Study of Kidney Disease in Children (ISKDC) and SQC classifications were compared in terms of the patient outcomes. Outcomes were defined as: Outcome A (n = 44) patients with no sign of renal disease, Outcome B (n = 32) patients with minor urinary abnormalities, and Outcome C (n = 4) patients with active renal disease. Results: The patients with outcome C had significantly higher biopsy scores and chronicity indices than patients in group A. There was no significant difference in areas under the curve between total biopsy SQC scores and ISKDC findings. Conclusions: Our results suggest that the modified SQC is not more sensitive than ISKDC classification for predicting the outcome in HSN cases.

Effectiveness and complications of mini-percutaneous nephrolithotomy in children: one center experience with 232 kidney units.

OBJECTIVE: To evaluate the efficacy and complications of mini-percutaneous nephrolithotomy (PCNL) surgery using 14-20 Fr access sheaths in pediatric patients, as well as the results of postoperative stone analysis and metabolic urine analysis. MATERIAL AND METHODS: We retrospectively evaluated the records of 206 pediatric patients (232 kidney units) who underwent mini-PCNL for kidney stones in our clinic between February 2011 and December 2018. We evaluated the demographic characteristics, complications, stone-free rates, and the results of chemical analysis and urinary metabolic analysis. RESULTS: The age ranged from 9 months to 16 years. The mean age was 5.1±3.9 years, and the median age was 3.5 years. The median stone burden was 200 mm2 (min: 100; max: 1600). Kidney stones were most commonly located in the pelvis in 118 (50.9%) patients, followed by lower calyceal stones in 42 (18.1%) and multiple calyceal stones in 38 (16.4%) patients, respectively. While the success of mini-PCNL was 80.6% after the first session, this rate increased to 87.9% after auxiliary treatments. The total complication rate was 12.9% according to modified Clavien classification. A postoperative stone analysis showed that calcium oxalate had the highest frequency with 61.1% of patients, followed by cystine stone with 21.3% of patients. Metabolic urine analysis revealed no abnormalities in 42.8% of patients. The most common metabolic abnormality was hyperoxaluria (32%), followed by hypercalcuria (19.6%). CONCLUSION: Mini-PCNL is a safe and effective procedure with reasonable complications for the treatment of pediatric kidney stones. All kinds of multidisciplinary efforts are required to remove kidney stones completely in pediatric patients.

Association of Mucopolysaccharidosis Type 4A and Bartter Syndrome.

A 6-year-old Syrian boy presented with complaints of facial dysmorphism and difficulty of walking. He had coarse face, macrocephaly, pectus carinatum, x-bain deformity, kyphosis, corneal clouding, and claw hand deformity. Galactose-6 sulphatase enzyme level was 0.1 nmol/mg.17 h (reference range, > 68 nmol/mg.17 h), compatible with Morquio syndrome. On laboratory examinations, potassium level was 2.9 mmol/L (reference range, 3.5 mmol/L to 5.1 mmol/L), sodium level was 130 mmol/L (reference range, 135 mmol/L to 148 mmol/L), and chloride level was 92 mmol/L (reference range, 101 mmol/L to 109 mmol/L). Blood pH was 7.5 and bicarbonate level was 31 mEq/L. Urine sodium and chloride levels were high. Arterial blood pressure was normal and these findings were consistent with Bartter syndrome. This is the first report of a patient with the association of Bartter syndrome and mucopolysaccharidosis type 4A, which was thought to be coincidental.