Comprehensive evaluation of patients with primary hyperoxaluria type 1: A nationwide study.

BACKGROUND: Primary hyperoxaluria type 1 (PH1) is characterized by increased endogenous oxalate production and deposition as calcium oxalate crystals. The main manifestations are nephrocalcinosis/nephrolithiasis, causing impaired kidney function. We aimed to evaluate the clinical characteristics and overall outcomes of paediatric PH1 patients in Turkey. METHODS: This is a nationwide, multicentre, retrospective study evaluating all available paediatric PH1 patients from 15 different paediatric nephrology centres in Turkey. Detailed patient data was collected which included demographic, clinical and laboratory features. Patients were classified according to their age and characteristics at presentation: patients presenting in the first year of life with nephrocalcinosis/nephrolithiasis (infantile oxalosis, Group 1), cases with recurrent nephrolithiasis diagnosed during childhood (childhood-onset PH1, Group 2), and asymptomatic children diagnosed with family screening (Group 3). RESULTS: Forty-eight patients had a mutation consistent with PH1. The most common mutation was c.971_972delTG (25%). Infantile oxalosis patients had more advanced chronic kidney disease (CKD) or kidney failure necessitating dialysis (76.9% vs. 45.5%). These patients had much worse clinical course and mortality rates seemed to be higher (23.1% vs. 13.6%). Patients with fatal outcomes were the ones with significant comorbidities, especially with cardiovascular involvement. Patients in Group 3 were followed with better outcomes, with no kidney failure or mortality. CONCLUSION: PH1 is not an isolated kidney disease but a systemic disease. Family screening helps to preserve kidney function and prevent systemic complications. Despite all efforts made with traditional treatment methods including transplantation, our results show devastating outcomes or mortality.

Parathyroid hormone and phosphate homeostasis in patients with Bartter and Gitelman syndrome: an international cross-sectional study.

BACKGROUND: Small cohort studies have reported high parathyroid hormone (PTH) levels in patients with Bartter syndrome and lower serum phosphate levels have anecdotally been reported in patients with Gitelman syndrome. In this cross-sectional study, we assessed PTH and phosphate homeostasis in a large cohort of patients with salt-losing tubulopathies. METHODS: Clinical and laboratory data of 589 patients with Bartter and Gitelman syndrome were provided by members of the European Rare Kidney Diseases Reference Network (ERKNet) and the European Society for Paediatric Nephrology (ESPN). RESULTS: A total of 285 patients with Bartter syndrome and 304 patients with Gitelman syndrome were included for analysis. Patients with Bartter syndrome type I and II had the highest median PTH level (7.5 pmol/L) and 56% had hyperparathyroidism (PTH >7.0 pmol/L). Serum calcium was slightly lower in Bartter syndrome type I and II patients with hyperparathyroidism (2.42 versus 2.49 mmol/L; P = .038) compared to those with normal PTH levels and correlated inversely with PTH (rs -0.253; P = .009). Serum phosphate and urinary phosphate excretion did not correlate with PTH. Overall, 22% of patients had low serum phosphate levels (phosphate-standard deviation score < -2), with the highest prevalence in patients with Bartter syndrome type III (32%). Serum phosphate correlated with tubular maximum reabsorption of phosphate/glomerular filtration rate (TmP/GFR) (rs 0.699; P < .001), suggesting renal phosphate wasting. CONCLUSIONS: Hyperparathyroidism is frequent in patients with Bartter syndrome type I and II. Low serum phosphate is observed in a significant number of patients with Bartter and Gitelman syndrome and appears associated with renal phosphate wasting.

Colostomy in children on chronic peritoneal dialysis.

BACKGROUND: This study aimed to evaluate outcome of children on chronic peritoneal dialysis (PD) with a concurrent colostomy. METHODS: Patients were identified through the International Pediatric Peritoneal Dialysis Network (IPPN) registry. Matched controls were randomly selected from the registry. Data were collected through the IPPN database and a survey disseminated to all participating sites. RESULTS: Fifteen centers reported 20 children who received chronic PD with a co-existing colostomy. The most common cause of end stage kidney disease was congenital anomalies of the kidney and urinary tract (n = 16, 80%). The main reason for colostomy placement was anorectal malformation (n = 13, 65%). The median age at colostomy creation and PD catheter (PDC) insertion were 0.1 (IQR, 0-2.2) and 2.8 (IQR 0.2-18.8) months, respectively. The colostomies and PDCs were present together for a median 18 (IQR, 4.9-35.8) months. The median age at PDC placement in 46 controls was 3.4 (IQR, 0.2-7.4) months of age. Fourteen patients (70%) developed 39 episodes of peritonitis. The annualized peritonitis rate was significantly higher in the colostomy group (1.13 vs. 0.70 episodes per patient year; p = 0.02). Predominant causative microorganisms were Staphylococcus aureus (15%) and Pseudomonas aeruginosa (13%). There were 12 exit site infection (ESI) episodes reported exclusively in colostomy patients. Seven colostomy children (35%) died during their course of PD, in two cases due to peritonitis. CONCLUSION: Although feasible in children with a colostomy, chronic PD is associated with an increased risk of peritonitis and mortality. Continued efforts to reduce infection risk for this complex patient population are essential.

Defects of CRB2 cause steroid-resistant nephrotic syndrome.

Nephrotic syndrome (NS), the association of gross proteinuria, hypoalbuminaemia, edema, and hyperlipidemia, can be clinically divided into steroid-sensitive (SSNS) and steroid-resistant (SRNS) forms. SRNS regularly progresses to end-stage renal failure. By homozygosity mapping and whole exome sequencing, we here identify recessive mutations in Crumbs homolog 2 (CRB2) in four different families affected by SRNS. Previously, we established a requirement for zebrafish crb2b, a conserved regulator of epithelial polarity, in podocyte morphogenesis. By characterization of a loss-of-function mutation in zebrafish crb2b, we now show that zebrafish crb2b is required for podocyte foot process arborization, slit diaphragm formation, and proper nephrin trafficking. Furthermore, by complementation experiments in zebrafish, we demonstrate that CRB2 mutations result in loss of function and therefore constitute causative mutations leading to NS in humans. These results implicate defects in podocyte apico-basal polarity in the pathogenesis of NS.

Time-averaged hemoglobin values, not hemoglobin cycling, have an impact on outcomes in pediatric dialysis patients.

BACKGROUND: During erythropoietin-stimulating agent (ESA) treatment, hemoglobin (Hb) levels usually fluctuate; this phenomenon is known as "Hb cycling (HC)." In this study, we aimed to evaluate the predictors of HC and its impact on left ventricular hypertrophy (LVH) as a patient-important outcome parameter in pediatric dialysis patients. METHODS: Records of patients followed up in nine pediatric nephrology centers between 2008 and 2013 were reviewed. More than 1 g/dL decrease or increase in Hb level was considered as HC. Patients were divided into two groups according to 12-month Hb trajectory as rare cycling (RC) (≤ 3) and frequent cycling (FC) (> 3 fluctuation) as well as three groups based on T-A-Hb levels: < 10, 10-11, and > 11 g/dL. RESULTS: Two hundred forty-five dialysis (160 peritoneal dialysis (PD) and 85 hemodialysis (HD)) patients aged 12.3 ± 5.1 (range 0.5-21) years were enrolled in this study. Fifty-two percent of the patients had RC, 45% had FC, and only 3% had no cycling. There were no differences between HC groups with respect to age, dialysis modality, having anemia, hospitalization rate, residual urine volume, and mortality. Although left ventricular mass index (LVMI) tended to be higher in RC than FC group (65 ± 37 vs 52 ± 23 g/m2.7, p = 0.056), prevalence of LVH was not different between the groups (p = 0.920). In regression analysis, FC was not a risk factor for LVH, but low T-A Hb level (< 10 g/dL) was a significant risk for LVH (OR = 0.414, 95% CI 0.177-0.966, p = 0.04). The target Hb levels were more often achieved in PD patients, and the number of deaths was significantly lower in non-anemic patients (Hb level > 11 g/dL). CONCLUSION: Hb cycling is common among dialysis patients. Severity of anemia rather than its cycling has more significant impact on the prevalence of LVH and on inflammatory state.

Effect of the timing of dialysis initiation on left ventricular hypertrophy and inflammation in pediatric patients.

BACKGROUND: The optimal time for dialysis initiation in adults and children with chronic kidney disease remains unclear. The aim of this study was to evaluate the impact of dialysis timing on different outcome parameters, in particular left ventricular (LV) morphology and inflammation, in pediatric patients receiving peritoneal dialysis and hemodialysis. METHODS: The medical records of pediatric dialysis patients who were followed-up in nine pediatric nephrology centers in Turkey between 2008 and 2013 were retrospectively reviewed. In addition to demographic data, we retrieved anthropometric measurements, data on dialysis treatment modalities, routine biochemical parameters, complete blood count, serum ferritin, parathormone, C-reactive protein (CRP), and albumin levels, as well as echocardiographic data and hospitalization records. The patients were divided into two groups based on their estimated glomerular filtration rate (eGFR) levels at dialysis initiation, namely, an early-start group, characterized by an eGFR of >10 ml/min/1.73 m2, and a late-start group, with an eGFR of < 7 ml/min/1.73 m2. The collected data were compared between these groups. RESULTS: A total of 245 pediatric dialysis patients (mean age ± standard deviation 12.3 ± 5.1 years, range 0.5-21 years) were enrolled in this study. Echocardiographic data were available for 137 patients, and the mean LV mass index (LVMI) was 58 ± 31 (range 21-215) g/m2.7. The LVMI was 75 ± 30 g/m2.7(n = 81) and 34 ± 6 g/m2.7(n = 56) in patients with or without LV hypertrophy (LVH) (p < 0.001). Early-start (eGFR >10 ml/min/1.73 m2) versus late-start dialysis (eGFR < 7 ml/min/1.73 m2) groups did not significantly differ in LVMI and LVH status (p > 0.05) nor in number of hospitalizations. Serum albumin levels were significantly higher in the early-dialysis group compared with the late-dialysis group (3.3 ± 0.7 vs. 3.1 ± 0.7 g/dl, respectively; p < 0.05). The early-start group had relatively higher time-averaged albumin levels (3.2 ± 0.5 vs. 3.1 ± 0.5 g/dl; p = > 0.05) and relatively lower CRP levels (3.64 ± 2.00 vs. 4.37 ± 3.28 mg/L, p > 0.05) than the late-start group, but these differences did not reach statistical significance. CONCLUSION: Although early dialysis initiation did not have a significant effect on important clinical outcome parameters, including LVH, inflammatory state, and hospitalization, in our pediatric dialysis patients, this area of study deserves further attention.

Early results of endoscopic treatment of vesicoureteral reflux with polyacrylate polyalcohol copolymer.

OBJECTIVE: To evaluate the early results of endoscopic treatment of vesicoureteral reflux (VUR) in children using polyacrylate polyalcohol copolymer (PPC). PATIENTS AND METHODS: We retrospectively reviewed 45 patients treated with subureteric injection of PPC in our clinic. The results of voiding cystouretrography performed on the 3rd postoperative month and the results of 1-year follow-up were evaluated. RESULTS: A total of 45 patients (57 ureters) underwent injection of PPC. The mean age of the patients was 6.5 years. There were 6 (10.5%) grade 1, 7 (12.2%) grade 2, 26 (45.6%) grade 3, 16 (28%) grade 4, and 2 (3.5%) grade 5 VUR. There were 11 overactive bladders, 2 duplex collecting systems, and 4 posterior urethral valves among the patients. Voiding cystouretrography postoperatively at the 3rd month showed that VUR had disappeared in 82.5% (47/57) of the ureters, downgraded to grade 2 and 3 in 7% (4/57), persisted in 5.2% (3/57) and upgraded in 5.2% (3/57). The success rate at the end of the first year was 98.1%. The procedure was free of complications such as fever, dysuria, lumbar pain or obstruction in all patients. No patient showed VUR recurrence at the end of the first year. CONCLUSIONS: The short-term results of our patients suggested that PPC can be safely and successfully used in the endoscopic treatment of VUR in children. However, further prospective, controlled trials showing the long-term results of the patients are needed.

High C-reactive protein and number of previous episodes at diagnosis increase the risk of catheter removal in peritoneal dialysis-related peritonitis in children.

BACKGROUND: A minority of patients with peritonitis require removal of peritoneal dialysis (PD) catheters. We examined risk factors at diagnosis that could predict the removal of PD catheter before obtaining the results of treatment success in children with peritonitis. METHODS: We analyzed 156 peritonitis episodes in 57 pediatric PD patients. RESULTS: The peritonitis rate was 0.68 peritonitis episode per patient year. Catheter removal was required in 22 of 156. C-reactive protein (CRP) ≥ ×10 of upper limit at diagnosis and increased previous episode number were found to be associated with catheter removal (OR [95% CI] 6.4 [2.3-18.1], p = 0.001 and 3.8 [1.4-10.6], p = 0.009). CONCLUSION: These findings supported that CRP could be an early marker in predicting catheter removal even before obtaining the results of treatment success. Furthermore, it should be kept in mind that the risk of catheter removal is high in patients with high number of previous episodes especially of three or more.

Automated complete blood counter, urine analyzer and urine dipstick test results are correlated with thoma cell counting chamber counts in the diagnosis of dialysis related peritonitis in children.

INTRODUCTION: Peritoneal dialysis is the treatment of choice for end-stage renal disease. Peritoneal dialysis related peritonitis is of great importance for patient and technical survival. The aim of our study was to evaluate the accuracy and the correlation between the three methods (complete blood count, urinalysis device, urine dipstick test) and with the reference manual method (Thoma Cell Counter Chamber). MATERIALS AND METHODS: We retrospectively analyzed 167 peritoneal fluid samples taken from 25 patients receiving peritoneal dialysis treatment. Leukocyte counts were evaluated with Thoma Cell Counter Chamber, complete blood count, urinalysis device and urine dipstick test. RESULTS: There was a significant positive correlation between Thoma Cell Counter Chamber and complete blood count results (Spearman's rho=0.70), between Thoma Cell Counter Chamber and urinalysis device (Spearman's rho=0.73), and between Thoma Cell Counter Chamber and urine dipstick test (Spearman's rho=0.71). Area under curve for complete blood count, urinalysis device and urine dipstick test were 0.93, 0.94 and 0.89 respectively, indicating good accuracy. Sensitivity and specificity were 89.7% and 86.7% in the complete blood count analysis (associated criterion: 130 cells/mm3). Sensitivity and specificity were 89.7% and 86.7% in the urinalysis device (associated criterion: 10 cells/HPF). Sensitivity and specificity were 79.6% and 91.4% when in the urine dipstick test analysis (associated criterion: +1 positivity). The Bland-Altman plot showed good agreement. CONCLUSION: Automatic complete blood count and urinalysis devices have good correlation and agreement with manual method in the diagnosis of peritonitis in the pediatric age group. Urine dipstick test in the home setting can be useful for screening patients with suspected peritonitis.

The assesment of prothrombotic potential using thrombin generation assay in pediatric patients with nephrotic syndrome: preliminary study.

BACKGROUND: Nephrotic syndrome (NS) is a common kidney disease associated with an increased risk of thrombotic events. The aim of this study was to assess the prothrombotic potential of patients with NS using the thrombin generation assay (TGA). METHODS: A total of 35 patients with NS, who were followed in the Division of Pediatric Nephrology in Behcet Uz Children`s Hospital, were included in the study. After the patients with Steroid Resistant NS (n:3) were excluded, 32 patients in total were evaluated for TGA. Patients were primarily classified according to their response to corticosteroid therapy. The control group consisted of 34 healthy volunteers with similar gender and age distribution to the patients. Blood urine nitrogen, creatinine, albumin, triglyceride, cholesterol, 24-hour proteinuria, platelets, erythrocyte sedimentation rate, C-reactive protein and thrombin generation values in activation and remission period of NS were compared. Moreover, TGA values of the patients in their remission period were compared with the values of those in the control group. RESULTS: Endogenous thrombin potential (ETP) and peak thrombin levels were significantly higher in the activation period than remission period of NS. Additionally, after the patients achieved remission, their ETP was still higher than the control group. There was a negative correlation between both ETP and peak thrombin levels of patients with serum albumin, whereas a significant positive correlation was detected with platelet levels. Thromboembolic events were not observed in any of the patients during follow-up. CONCLUSIONS: Nephrotic syndrome is strongly associated with hypercoagulopathy as assessed by TGA during active NS. The present study reinforces the usefulness of TGA as a marker of hypercoagulability in pediatric patients with NS. Further studies are needed in this regard.

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.

Contractility reserve in children undergoing dialysis by dobutamine stress echocardiography.

Left ventricular hypertrophy is an adaptive mechanism in children undergoing chronic dialysis to improve contractility at rest. The aim of this study was to determine the left ventricular performance and contractility reserve by "dobutamine stress echocardiography" in children undergoing chronic dialysis. Thirty-five children undergoing dialysis and 24 healthy subjects were enrolled in this prospective study. We evaluated contractility by means of end-systolic wall stress-velocity of circumferential fiber shortening (VCFc) in 24 healthy subjects and 35 dialysis patients. Dobutamine stress echocardiography was obtained only in children undergoing dialysis. Patients were divided into two groups according to left ventricular mass index. Contractile reserve was estimated by the difference in contractility at rest versus during echocardiography. Significantly higher VCFc (p = 0.008) and VCFc (p = 0.002) differences at rest were observed in the patient group compared to healthy subjects. Children undergoing dialysis had a higher left ventricular mass index compared with controls (42.38 ± 12.41 vs. 17.57 ± 3.66 g/m(2.7), respectively; p = 0.001). Patients with left ventricular hypertrophy had a significantly lower contractile reserve compared with patients without left ventricular hypertrophy (p = 0.013). These findings suggest that children undergoing dialysis have increased left ventricular mass and contractility at rest. However, the contractile reserve during dobutamine stress echocardiography was reduced. Dobutamine stress echocardiography may identify children undergoing dialysis at risk of progressing to systolic dysfunction and heart failure.

A new mutation associated with Pierson syndrome. / Una nueva mutación asociada con el síndrome de Pierson.

Pierson syndrome is characterized by congenital nephrotic syndrome and bilateral microcoria. Genetically, mutations in the LAMB2 gene, which encodes the laminin ß2 chain, lead to this disorder. To date, 98 cases and 50 different mutations have been reported in literature. There are no specific therapies for Pierson syndrome and treatment is supportive. The prognosis is poor because of progressive impairment of renal function and complications of renal failure. We report a novel homozygous mutation (c.1890G>T, p.Q630H) in the LAMB2 gene in a patient with Pierson syndrome who had atypical phenotypic feature such as epidermolysis bullosa.

El síndrome de Pierson se caracteriza por la presencia de síndrome nefrótico congénito y microcoria bilateral. Genéticamente, este trastorno está ocasionado por mutaciones en el gen LAMB2, que codifica la cadena ß2 de la laminina. Hasta la fecha, en la bibliografía se informaron 98 casos y 50 mutaciones diferentes. No existen terapias específicas para el síndrome de Pierson, y el tratamiento es complementario. El pronóstico es malo por la disfunción renal progresiva y las complicaciones de la insuficiencia renal. En este artículo, se informa sobre una mutación homocigota novedosa (c.1890G>C [p.Q630H]) en el gen LAMB2 en una paciente con síndrome de Pierson que tenía un fenotipo atípico, como epidermólisis ampollosa.

Children with chronic-refractory autoimmune cytopenias: a single center experience.

BACKGROUND AND OBJECTIVES: Autoimmune cytopenias are a group of heterogeneous disorders characterized by immune-mediated destruction of one or more hematopoietic lineage cells. The differential diagnosis of children with autoimmune cytopenias requires much time and laboratory investigations. The aim of the present study was to evaluate the clinical course and significance of autoimmune cytopenias due to immunodeficiency or autoimmune diseases in children at a single children`s hospital. METHOD: Between February 1997 and September 2015, chronic/refractory autoimmune cytopenias patient data were evaluated retrospectively. Twenty-three patients were assessed in this study. RESULTS: The median duration of following was 2.6 years (4 months-18.5 years). The median age of diagnosis was 3.1 years (6 months-16 years). A total of 13 patients (56.5%) had single-lineage and 10 (46.5%) had multilineage cytopenias. The most frequent single-lineage cytopenia was thrombocytopenia, followed by anemia. In 22 of the patients, cytopenias was detected before the primary diseases. All of the patients were treated with corticosteroids or intravenous immune globulin as first-line treatment. Ten patients (43.5%) needed second or further-line immunosuppressive therapies that patients diagnosed as systemic lupus erythematosus, hypogammaglobulinemia, or common variable immunodeficiency. A total of 8 patients (34.7%) recovered from autoimmune cytopenias after the treatment of primer disease. Cytopenias were continued in 14 patients. CONCLUSION: Cytopenia may be the first finding of an immunodeficiency or autoimmune disease and primary disease may be diagnosed in the clinical course. Taking the new targeted treatment options into consideration; early diagnosis is likely to become more important in the near-future in order to begin the treatment for the underlying disease as early as possible.

Challenges in the management of an ignored cause of hyperammonemic encephalopathy: pyruvate carboxylase deficiency.

Pyruvate carboxylase (PC) deficiency is a rare autosomal recessive disease and provides clinics in three essential phenotypes. Type B PC deficiency is characterized by lactic acidosis and hyperammonemia. We report a Turkish patient who was diagnosed with type B PC deficiency. Despite the application of anaplerotic treatment with biotin, citrate and arginine-aspartate, continuous veno-venous hemodialysis (CVVHD) treatments were applied due to the failure to keep hyperammonemia and lactic acidosis under control. Ammonia values increasing to 860 µmol/L were observed. A homozygous novel variant was detected in PC gene analyses containing a 12-base pair deletion on exon 8. Although the mutation found was not reported previously, it was accepted as a pathogenic variant due to its presence in a functional region of the protein. In type B PC deficiency, although a high level of ammonia is expected, it rarely exceeds 200 µmol/L. As far as we know, the present case has the highest ammonia values in the literature. This paper has been shared to highlight to keep PC deficiency in mind regarding the differential diagnosis of hyperammonemia, particularly in the presence of lactic acidosis, and to serve as a model for the use of different modalities in the management process of PC deficiency.

Mutational analysis of CLC-5, cofilin and CLC-4 in patients with Dent's disease.

BACKGROUND/AIMS: Dent's disease is caused by mutations in the chloride/proton antiporter, CLC-5, or oculo-cerebro-renal-syndrome-of-Lowe (OCRL1) genes. METHODS: Eighteen probands with Dent's disease were investigated for mutations in CLC-5 and two of its interacting proteins, CLC-4 and cofilin. Wild-type and mutant CLC-5s were assessed in kidney cells. Urinary calcium excretion following an oral calcium challenge was studied in one family. RESULTS: Seven different CLC-5 mutations consisting of two nonsense mutations (Arg347Stop and Arg718Stop), two missense mutations (Ser244Leu and Arg516Trp), one intron 3 donor splice site mutation, one deletion-insertion (nt930delTCinsA) and an in-frame deletion (523delVal) were identified in 8 patients. In the remaining 10 patients, DNA sequence abnormalities were not detected in the coding regions of CLC-4 or cofilin, and were independently excluded for OCRL1. Patients with CLC-5 mutations were phenotypically similar to those without. The donor splice site CLC-5 mutation resulted in exon 3 skipping. Electrophysiology demonstrated that the 523delVal CLC-5 mutation abolished CLC-5-mediated chloride conductance. Sixty percent of women with the CLC-5 deletion-insertion had nephrolithiasis, although calcium excretion before and after oral calcium challenge was similar to that in unaffected females. CONCLUSIONS: Three novel CLC-5 mutations were identified, and mutations in OCRL1, CLC-4 and cofilin excluded in causing Dent's disease in this patient cohort.

The role of cardiac troponin T in detection of cardiac damage and long term mortality in children with chronic renal disease.

Karadas U, Özdemir Karadas N, Bak M, Serdaroglu E, Yilmazer MM, Mese T. The role of cardiac troponin T in detection of cardiac damage and long term mortality in children with chronic renal disease. Turk J Pediatr 2019; 61: 873-878. In this study, we aimed to evaluate the role of cardiac troponin T (cTnT) in detecting myocardial involvement in children with chronic kidney disease (CKD) and to investigate whether it contributes to predicting cardiac involvement and mortality at follow-up. Echocardiographic evaluations were performed on a sample of 69 patients, of which 33 (47.8%) were female, with grade 3, 4 and 5 chronic renal failure and end-stage renal failure. Patients with normal cTnT levels and patients with high cTnT levels were compared. cTnT levels were observed to be high in 13 (19%) of the 69 patients. The comparison between the patients with normal cTnT levels and patients with high cTnT levels with regards to the echocardiographic findings revealed that in the latter group, the average ejection fraction and fractional shortening levels were lower (p=0.003 and p=0.013, respectively), the detection rate of left ventricular systolic dysfunction was 5.5 times higher and the rate of detection of left ventricular hypertrophy (LVH) was 3 times higher (p=0.004, p=0.011). In this study, it was shown that it is possible to obtain information about cardiac effects by examining the serum cTnT level before clinical symptoms occur in children with CKD, and that cTnT can be used for screening purposes.

Global Variation of Nutritional Status in Children Undergoing Chronic Peritoneal Dialysis: A Longitudinal Study of the International Pediatric Peritoneal Dialysis Network.

While children approaching end-stage kidney disease (ESKD) are considered at risk of uremic anorexia and underweight they are also exposed to the global obesity epidemic. We sought to investigate the variation of nutritional status in children undergoing chronic peritoneal dialysis (CPD) around the globe. The distribution and course of body mass index (BMI) standard deviation score over time was examined prospectively in 1001 children and adolescents from 35 countries starting CPD who were followed in the International Pediatric PD Network (IPPN) Registry. The overall prevalence of underweight, and overweight/obesity at start of CPD was 8.9% and 19.7%, respectively. Underweight was most prevalent in South and Southeast Asia (20%), Central Europe (16.7%) and Turkey (15.2%), whereas overweight and obesity were most common in the Middle East (40%) and the US (33%). BMI SDS at PD initiation was associated positively with current eGFR and gastrostomy feeding prior to PD start. Over the course of PD BMI SDS tended to increase on CPD in underweight and normal weight children, whereas it decreased in initially overweight patients. In infancy, mortality risk was amplified by obesity, whereas in older children mortality was markedly increased in association with underweight. Both underweight and overweight are prevalent in pediatric ESKD, with the prevalence varying across the globe. Late dialysis start is associated with underweight, while enteral feeding can lead to obesity. Nutritional abnormalities tend to attenuate with time on dialysis. Mortality risk appears increased with obesity in infants and with underweight in older children.

The Emerging Resistance in Nosocomial Urinary Tract Infections: From the Pediatrics Perspective.

BACKGROUND: Healthcare-associated infections results in increased health care costs and mortality. There are limited studies concerning the distribution of the etiologic agents and the resistance patterns of the microorganisms causing healthcare-associated urinary tract infections (HA-UTI) in pediatric settings. OBJECTIVES: The aim of this study was to evaluate the distribution and antibiotic susceptibility patterns of pathogens causing HA-UTI in children. MATERIAL AND METHODS: Isolates from 138 children with UTI who were hospitalized in pediatric, neonatal and pediatric surgery intensive care units were reviewed. RESULTS: Most common isolated organism was Klebsiella pneumoniae (34.1%) and Escherichia coli (26.8%). Among the Pseudomonas aeruginosa, Meropenem and imipenem resistance rates were 46.2% and 38.5%. Extended-spectrum beta-lactamase (ESBL) production was present in 48 Klebsiella species (82.8%). Among ESBL positive Klebsiella species, the rate of meropenem and imipenem resistance was 18.8%, and ertapenem resistance was 45.9%. Extended spectrum beta-lactamase production was present in 27 (72.9%) Escherichia coli species. Among ESBL positive E. coli, the rate of meropenem and imipenem resistance was 7.4%, and ertapenem resistance was 14.8. CONCLUSIONS: Emerging meropenem resistance in P. aeruginosa, higher rates of ertapenem resistance in ESBL positive ones in E. coli and Klebsiella species in pediatric nosocomial UTI are important notifying signs for superbug infections.