Publications by authors named "Erkin Serdaroglu"

45 Publications

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

Turk J Pediatr 2020 ;62(4):525-532

Departments of Pediatric Hematology-Oncology, Dr. Behçet Uz Children Research and Training Hospital, İzmir, Turkey.

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.
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http://dx.doi.org/10.24953/turkjped.2020.04.001DOI Listing
January 2020

A new mutation associated with Pierson syndrome.

Arch Argent Pediatr 2020 06;118(3):e288-e291

Department of Medical Genetics, Tepecik Training and Research Hospital, Izmir, Turkey.

Pierson syndrome is characterized by congenital nephrotic syndrome and bilateral microcoria. Genetically, mutations in the LAMB2 gene, which encodes the laminin β2 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.
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http://dx.doi.org/10.5546/aap.2020.eng.e288DOI Listing
June 2020

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

J Pediatr Endocrinol Metab 2020 Apr;33(4):569-574

Behçet Uz Children Training & Research Hospital, Neonatology Department, Izmir, Turkey.

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.
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http://dx.doi.org/10.1515/jpem-2019-0307DOI Listing
April 2020

Colostomy in children on chronic peritoneal dialysis.

Pediatr Nephrol 2020 01 30;35(1):119-126. Epub 2019 Oct 30.

Children's Mercy Kansas City, Kansas City, MO, USA.

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.
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http://dx.doi.org/10.1007/s00467-019-04372-xDOI Listing
January 2020

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

Sci Rep 2019 03 20;9(1):4886. Epub 2019 Mar 20.

Children's Mercy Hospital, Kansas City, MO, USA.

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.
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http://dx.doi.org/10.1038/s41598-018-36975-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6426856PMC
March 2019

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(6):873-878

Divisions of Pediatric Cardiology, Dr. Behçet Uz Children's Hospital, İzmir, Turkey.

Karadaş U, Özdemir Karadaş N, Bak M, Serdaroğlu E, Yılmazer MM, Meşe 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.
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http://dx.doi.org/10.24953/turkjped.2019.06.008DOI Listing
July 2020

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

Mediterr J Hematol Infect Dis 2018 1;10(1):e2018055. Epub 2018 Sep 1.

Dr. Behçet Uz Children's Hospital, İzmir, Turkey.

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.
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http://dx.doi.org/10.4084/MJHID.2018.055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6131100PMC
September 2018

Mutations in multiple components of the nuclear pore complex cause nephrotic syndrome.

J Clin Invest 2018 10 4;128(10):4313-4328. Epub 2018 Sep 4.

Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.

Steroid-resistant nephrotic syndrome (SRNS) almost invariably progresses to end-stage renal disease. Although more than 50 monogenic causes of SRNS have been described, a large proportion of SRNS remains unexplained. Recently, it was discovered that mutations of NUP93 and NUP205, encoding 2 proteins of the inner ring subunit of the nuclear pore complex (NPC), cause SRNS. Here, we describe mutations in genes encoding 4 components of the outer rings of the NPC, namely NUP107, NUP85, NUP133, and NUP160, in 13 families with SRNS. Using coimmunoprecipitation experiments, we showed that certain pathogenic alleles weakened the interaction between neighboring NPC subunits. We demonstrated that morpholino knockdown of nup107, nup85, or nup133 in Xenopus disrupted glomerulogenesis. Re-expression of WT mRNA, but not of mRNA reflecting mutations from SRNS patients, mitigated this phenotype. We furthermore found that CRISPR/Cas9 knockout of NUP107, NUP85, or NUP133 in podocytes activated Cdc42, an important effector of SRNS pathogenesis. CRISPR/Cas9 knockout of nup107 or nup85 in zebrafish caused developmental anomalies and early lethality. In contrast, an in-frame mutation of nup107 did not affect survival, thus mimicking the allelic effects seen in humans. In conclusion, we discovered here that mutations in 4 genes encoding components of the outer ring subunits of the NPC cause SRNS and thereby provide further evidence that specific hypomorphic mutations in these essential genes cause a distinct, organ-specific phenotype.
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http://dx.doi.org/10.1172/JCI98688DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6159964PMC
October 2018

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

Pediatr Nephrol 2018 11 13;33(11):2143-2150. Epub 2018 Aug 13.

Department of Pediatric Nephrology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.

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/m, 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.
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http://dx.doi.org/10.1007/s00467-018-4013-4DOI Listing
November 2018

Whole Exome Sequencing of Patients with Steroid-Resistant Nephrotic Syndrome.

Clin J Am Soc Nephrol 2018 01 10;13(1):53-62. Epub 2017 Nov 10.

Due to the number of contributing authors, the affiliations are provided in the Supplemental Material.

Background And Objectives: Steroid-resistant nephrotic syndrome overwhelmingly progresses to ESRD. More than 30 monogenic genes have been identified to cause steroid-resistant nephrotic syndrome. We previously detected causative mutations using targeted panel sequencing in 30% of patients with steroid-resistant nephrotic syndrome. Panel sequencing has a number of limitations when compared with whole exome sequencing. We employed whole exome sequencing to detect monogenic causes of steroid-resistant nephrotic syndrome in an international cohort of 300 families.

Design, Setting, Participants, & Measurements: Three hundred thirty-five individuals with steroid-resistant nephrotic syndrome from 300 families were recruited from April of 1998 to June of 2016. Age of onset was restricted to <25 years of age. Exome data were evaluated for 33 known monogenic steroid-resistant nephrotic syndrome genes.

Results: In 74 of 300 families (25%), we identified a causative mutation in one of 20 genes known to cause steroid-resistant nephrotic syndrome. In 11 families (3.7%), we detected a mutation in a gene that causes a phenocopy of steroid-resistant nephrotic syndrome. This is consistent with our previously published identification of mutations using a panel approach. We detected a causative mutation in a known steroid-resistant nephrotic syndrome gene in 38% of consanguineous families and in 13% of nonconsanguineous families, and 48% of children with congenital nephrotic syndrome. A total of 68 different mutations were detected in 20 of 33 steroid-resistant nephrotic syndrome genes. Fifteen of these mutations were novel. , , , and were the most common genes in which we detected a mutation. In another 28% of families, we detected mutations in one or more candidate genes for steroid-resistant nephrotic syndrome.

Conclusions: Whole exome sequencing is a sensitive approach toward diagnosis of monogenic causes of steroid-resistant nephrotic syndrome. A molecular genetic diagnosis of steroid-resistant nephrotic syndrome may have important consequences for the management of treatment and kidney transplantation in steroid-resistant nephrotic syndrome.
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http://dx.doi.org/10.2215/CJN.04120417DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5753307PMC
January 2018

The Clinical and Mutational Spectrum of Turkish Patients with Cystinosis.

Clin J Am Soc Nephrol 2017 Aug 9. Epub 2017 Aug 9.

Due to the number of contributing authors, the affiliations are provided in the Supplemental Material.

Background And Objectives: Infantile nephropathic cystinosis is a severe disease that occurs due to mutations in the cystinosis gene, and it is characterized by progressive dysfunction of multiple organs; >100 cystinosis gene mutations have been identified in multiple populations. Our study aimed to identify the clinical characteristics and spectrum of cystinosis gene mutations in Turkish pediatric patients with cystinosis.

Design, Setting, Participants, & Measurements: We identified the clinical characteristics and spectrum of cystinosis gene mutations in Turkish patients with cystinosis in a multicenter registry that was established for data collection. The data were extracted from this registry and analyzed.

Results: In total, 136 patients (75 men and 61 women) were enrolled in the study. The most common clinical findings were growth retardation, polyuria, and loss of appetite. None of the patients had the 57-kb deletion, but seven novel mutations were identified. The most common mutations identified were c.681G>A (p.Glu227Glu; 31%), c.1015G>A (p.Gly339Arg; 22%), and c.18_21 del (p.Thr7Phefs*7; 14%). These mutations were associated with earlier age of disease onset than the other mutations. To understand the effects of these allelic variants on clinical progression, the mutations were categorized into two major groups (missense versus deletion/duplication/splice site). Although patients with missense mutations had a better eGFR at the last follow-up visit, the difference was not significant. Patients in whom treatment began at age <2 years old had later onset of ESRD (=0.02). Time to ESRD did not differ between the patients with group 1 and group 2 mutations.

Conclusions: The most common cystinosis gene mutations identified in Turkey were c.681G>A (p.Glu227Glu), c.1015G>A (p.Gly339Arg), and c.18_21 del (p.Thr7Phefs*7). Patients with less severe cystinosis gene mutations tend to have better kidney outcome.
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http://dx.doi.org/10.2215/CJN.00180117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5628704PMC
August 2017

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

Pediatr Nephrol 2017 09 10;32(9):1595-1602. Epub 2017 Apr 10.

Department of Pediatric Nephrology, Tepecik Training and Research Hospital, İzmir, Turkey.

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 m, and a late-start group, with an eGFR of < 7 ml/min/1.73 m. 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/m. The LVMI was 75 ± 30 g/m(n = 81) and 34 ± 6 g/m(n = 56) in patients with or without LV hypertrophy (LVH) (p < 0.001). Early-start (eGFR >10 ml/min/1.73 m) versus late-start dialysis (eGFR < 7 ml/min/1.73 m) 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.
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http://dx.doi.org/10.1007/s00467-017-3660-1DOI Listing
September 2017

Peritoneal Dialysis Access Revision in Children: Causes, Interventions, and Outcomes.

Clin J Am Soc Nephrol 2017 01 29;12(1):105-112. Epub 2016 Nov 29.

Due to the number of contributing authors, the affiliations are provided in the Supplemental Material.

Background And Objectives: Little published information is available about access failure in children undergoing chronic peritoneal dialysis. Our objectives were to evaluate frequency, risk factors, interventions, and outcome of peritoneal dialysis access revision.

Design, Setting, Participants, & Measurements: Data were derived from 824 incident and 1629 prevalent patients from 105 pediatric nephrology centers enrolled in the International Pediatric Peritoneal Dialysis Network Registry between 2007 and 2015.

Results: In total, 452 access revisions were recorded in 321 (13%) of 2453 patients over 3134 patient-years of follow-up, resulting in an overall access revision rate of 0.14 per treatment year. Among 824 incident patients, 186 (22.6%) underwent 188 access revisions over 1066 patient-years, yielding an access revision rate of 0.17 per treatment year; 83% of access revisions in incident patients were reported within the first year of peritoneal dialysis treatment. Catheter survival rates in incident patients were 84%, 80%, 77%, and 73% at 12, 24, 36, and 48 months, respectively. By multivariate logistic regression analysis, risk of access revision was associated with younger age (odds ratio, 0.93; 95% confidence interval, 0.92 to 0.95; P<0.001), diagnosis of congenital anomalies of the kidney and urinary tract (odds ratio, 1.28; 95% confidence interval, 1.03 to 1.59; P=0.02), coexisting ostomies (odds ratio, 1.42; 95% confidence interval, 1.07 to 1.87; P=0.01), presence of swan neck tunnel with curled intraperitoneal portion (odds ratio, 1.30; 95% confidence interval, 1.04 to 1.63; P=0.02), and high gross national income (odds ratio, 1.10; 95% confidence interval, 1.02 to 1.19; P=0.01). Main reasons for access revisions included mechanical malfunction (60%), peritonitis (16%), exit site infection (12%), and leakage (6%). Need for access revision increased the risk of peritoneal dialysis technique failure or death (hazard ratio, 1.35; 95% confidence interval, 1.10 to 1.65; P=0.003). Access dysfunction due to mechanical causes doubled the risk of technique failure compared with infectious causes (hazard ratio, 1.95; 95% confidence interval, 1.20 to 2.30; P=0.03).

Conclusions: Peritoneal dialysis catheter revisions are common in pediatric patients on peritoneal dialysis and complicate provision of chronic peritoneal dialysis. Attention to potentially modifiable risk factors by pediatric nephrologists and pediatric surgeons should be encouraged.
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http://dx.doi.org/10.2215/CJN.05270516DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5220659PMC
January 2017

Incidence and causes of urolithiasis in children between 0-2 years.

Minerva Urol Nefrol 2017 Apr 13;69(2):181-188. Epub 2016 Sep 13.

Department of Pediatric Nephrology, Dr Behcet Uz Child Disease And Surgery Education And Research Hospital, Izmir, Turkey.

Background: Urolithiasis (UL) is a common problem in pediatric nephrology practice. About 9-23% of all pediatric UL cases consist of patients under 1 years old. The aim of the present study was to determine etiologic causes, clinical features and short term prognosis of urolithiasis in the first two years of life.

Methods: Two-hundred children between 0-2 years of age (mean age 10.3±6.1 months) with urolithiasis were included to the study. All children were completely evaluated for urolithiasis etiology. Patients were followed for at least 1 year with 3-month follow-up intervals.

Results: The mean follow-up duration was 36.2 months. Family history was positive for urolithiasis in 99 (49.5%) patients. The cause of admission were urinary tract infection and related symptoms in 101 (50.5%), incidentally during imaging for other causes in 40 (20%), stone passage in 21 (10.5%), hematuria in 18 (9%), voiding difficulty in 14 (7%) and antenatal detected urinary anomaly in 6 (3%) patients. Accompanying urinary anomalies (anatomical defects) in 51 (25.5%) patients were detected primarily including vesiculoureteral reflux (VUR) in 32 (62.9%) of them. Development of new stones was determined in 45 (22.5%) patients in the first year, in 15 (22%) patients in the second year and in 8 (36.3%) patients in the third year.

Conclusions: In result, among pediatric urinary stone diseases, infantile UL appears to be a seperate clinical entity in terms of both the etiological characteristics and the clinical course of the disease. Furthermore, when an infant is presented with nonspecific symptoms for kidney stone, a renal ultrasonography could be performed for detecting nephrolithiasis.
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http://dx.doi.org/10.23736/S0393-2249.16.02675-8DOI Listing
April 2017

The experience of canakinumab in renal amyloidosis secondary to Familial Mediterranean fever.

Mol Cell Pediatr 2016 Dec 15;3(1):33. Epub 2016 Aug 15.

Dr. Behcet Uz Children Diseases Teaching and Research Hospital Pediatric Nephrology, Izmir, Turkey.

Introduction: Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by self-limited recurrent attacks of fever and serositis. Patients may develop renal amyloidosis. Colchicine prevents attacks and renal amyloidosis. Five to 10 % of the patients with FMF are resistant or intolerant to colchicine.

Case Description: Herein, we reported our experience with clinical-laboratory features and treatment responses of a pediatric FMF patient with amyloidosis treated with canakinumab. We observed a significant decrease in proteinuria and increase growth in the patient.

Discussion And Evaluation: The most serious complication of FMF is the development of AA type amyloidosis which is characterized by proteinuria. Colchicine is the prototype drug that decreases production of amyloidogenic precursor protein. Occasionally, colchicine inadequate patient is observed, as in our case. Canakinumab is a human anti-IL-1β monoclonal antibody. Previously, canakinumab efficacy were shown in a limited number of studies.

Conclusions: Our data, though limited to only one patient, emphasize that therapeutic intervention with canakinumab seems to be improve kidney function in colchicine-resistant FMF with renal amyloidosis.
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http://dx.doi.org/10.1186/s40348-016-0058-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5010548PMC
December 2016

Mutations in nuclear pore genes NUP93, NUP205 and XPO5 cause steroid-resistant nephrotic syndrome.

Nat Genet 2016 Apr 15;48(4):457-65. Epub 2016 Feb 15.

Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.

Nucleoporins are essential components of the nuclear pore complex (NPC). Only a few diseases have been attributed to NPC dysfunction. Steroid-resistant nephrotic syndrome (SRNS), a frequent cause of chronic kidney disease, is caused by dysfunction of glomerular podocytes. Here we identify in eight families with SRNS mutations in NUP93, its interaction partner NUP205 or XPO5 (encoding exportin 5) as hitherto unrecognized monogenic causes of SRNS. NUP93 mutations caused disrupted NPC assembly. NUP93 knockdown reduced the presence of NUP205 in the NPC, and, reciprocally, a NUP205 alteration abrogated NUP93 interaction. We demonstrate that NUP93 and exportin 5 interact with the signaling protein SMAD4 and that NUP93 mutations abrogated interaction with SMAD4. Notably, NUP93 mutations interfered with BMP7-induced SMAD transcriptional reporter activity. We hereby demonstrate that mutations of NUP genes cause a distinct renal disease and identify aberrant SMAD signaling as a new disease mechanism of SRNS, opening a potential new avenue for treatment.
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http://dx.doi.org/10.1038/ng.3512DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4811732PMC
April 2016

Thrombotic Microangiopathy with Complement Factor H Gene Mutations Unassociated with Atypical Hemolytic Uremic Syndrome.

Turk J Haematol 2015 Sep;32(3):275-6

Dr. Behçet Uz Children's Hospital, Clinic of Hematology, İzmir, Turkey Phone: +90 532 355 42 28 E-mail:

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http://dx.doi.org/10.4274/tjh.2015.0084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4563206PMC
September 2015

Defects of CRB2 cause steroid-resistant nephrotic syndrome.

Am J Hum Genet 2015 Jan 31;96(1):153-61. Epub 2014 Dec 31.

Department of Immunology, Genetics, and Pathology, Uppsala University, 751 85 Uppsala, Sweden. Electronic address:

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.
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http://dx.doi.org/10.1016/j.ajhg.2014.11.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4289689PMC
January 2015

Evaluation of left atrial functions in children with chronic renal failure.

Anadolu Kardiyol Derg 2014 May 5;14(3):280-5. Epub 2014 Mar 5.

Clinic of Pediatric Cardiology, İzmir Buca Gynecology and Obstetrics and Pediatric Diseases Hospital; İzmir-Turkey.

Objective: One-quarter of deaths in children with chronic renal failure is due to cardiovascular complications. Conventional echocardiographic methods are insufficient for evaluating systolic functions in children with chronic renal failure. The aim of the present study was to investigate cardiac functions in children with chronic renal failure by evaluating left atrial volume and functions.

Methods: The present cross-sectional observational study included 44 children undergoing dialysis, 16 children with chronic renal failure but not yet on dialysis, and 20 healthy control subjects. Transthoracic echocardiography was performed for all children. Variables regarding to left ventricle and atrium (left atrial systolic force, left atrial systolic force index, left atrial volume, left ventricular mass index, and relative wall thickness) were measured using two-dimensional and M-mode echocardiography.

Results: Left atrial systolic force index was negatively correlated with systolic blood pressure and left ventricular mass (p=0.01, r=0.266 and p=0.02, r=0.347, respectively). However, it was positively correlated with both early and late diastolic mitral inflow velocity (r=0.518, p=0.001 and r=0.828, p=0.001, respectively). There were no significant difference among the groups in terms of left atrial systolic force index and left atrial volume. However, left atrial systolic force index was higher in children with chronic renal failure but not yet on dialysis.

Conclusion: Left atrial systolic force was negatively correlated with systolic blood pressure and left ventricular mass. These findings suggested that evaluating left atrial systolic force and left atrial volume were useful to determine diastolic dysfunction and the necessity of dialysis in patient with chronic renal failure.
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http://dx.doi.org/10.5152/akd.2014.4675DOI Listing
May 2014

Association of mannose binding lectin codon 54 polymorphism with predisposition to Henoch-Schönlein purpura in childhood.

Int J Rheum Dis 2014 Mar 28;17(3):317-20. Epub 2014 Feb 28.

Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir, Turkey.

Aim: Immune and inflammatory response activation is a common feature of systemic vasculitis. There is a protein called mannose binding lectin (MBL) that was reported to play an important role in innate immunity. MBL polymorphisms in the MBL gene cause predisposition to infectious and autoimmune diseases. There is no study in the literature investigating the association between MBL polymorphisms and Henoch-Schönlein purpura (HSP) to date. Therefore, the aim of this study is to determine the presence of any association between MBL gene variants and HSP in a child population.

Method: Codon 54 polymorphism in exon 1 of the MBL gene was investigated by polymerase chain reaction - restriction fragment length polymorphism method in 100 children diagnosed as having HSP and 100 age-matched healthy controls.

Results: The mutant B allele frequency was not significantly higher in the patient group (16%) compared to the control group (14%). AB genotype was found to be 28% and 26% in the patient group and healthy control group, respectively. AA genotype was found in 70% of the children with HSP and 73% of the healthy control group.

Conclusion: These results suggest that codon 54 polymorphism in the MBL gene may hardly play a role in susceptibility to HSP in children, the first time this has been reported in the literature.
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http://dx.doi.org/10.1111/1756-185X.12321DOI Listing
March 2014

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

Urol Int 2014 5;92(2):219-22. Epub 2013 Dec 5.

Department of Pediatric Surgery, Dr. Behçet Uz Children's Training Hospital, Izmir, Turkey.

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.
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http://dx.doi.org/10.1159/000354879DOI Listing
December 2014

Clinical and radiological course of simple renal cysts in children.

Urology 2014 Feb 1;83(2):433-7. Epub 2013 Nov 1.

Department of Pediatrics, Dokuz Eylul University, Medical Faculty, Balcova, Izmir, Turkey.

Objective: To evaluate the clinical and, particularly, radiological course of simple renal cysts in children.

Materials And Methods: Children with simple renal cysts were retrospectively evaluated, especially for change in the cyst diameter during follow-up and complications. In addition, the rate of increase in cyst size per year was calculated, and those characteristics of the cyst were analyzed to predict aggressiveness.

Results: Simple renal cysts were detected in 45 (21 male) patients. Mean ages at diagnosis and follow-up period were 7.4 ± 4.9 and 2.9 ± 1.8 years, respectively. Forty-one of the 45 patients were followed up for longer than 1 year. Diameter of the cyst increased in 20 (49%), decreased in 4 (10%), unchanged in 13 (31%), and disappeared in 4 (10%) of patients. The average size increase and average rate of enlargement in simple cysts were 0.3 mm and 1.0% per year, respectively. Furthermore, in 19 (95%) patients, the cyst size increased in the first 2 years. Among baseline parameters, only initial cyst size was an independent predictor of annual growth rates (beta = 0.628; P <.001). The relationship between the initial cyst size and annual growth rates was determined as positive (r = 0.459, P = .003). Two patients with large cysts developed severe complication in the first 6 months. One of these underwent nephrectomy because of rapid increase in cyst diameter (170 mm), renal artery/vein compression, and massive hematuria. In the other patient with severe loin pain regarding simple cyst (73 mm), percutaneous aspiration was performed.

Conclusion: Simple renal cysts in childhood tend to slowly increase in size. However, regular radiological follow-up might be important, especially in children with large size of cyst at diagnosis, because of more rapid increase in cyst size.
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http://dx.doi.org/10.1016/j.urology.2013.08.055DOI Listing
February 2014

Association between RAS gene polymorphisms (ACE I/D, AGT M235T) and Henoch-Schönlein purpura in a Turkish population.

Dis Markers 2013 ;34(1):23-32

Molecular Medicine Laboratory, Children's Hospital, Faculty of Medicine, Ege University, Bornova, Izmir, Turkey.

Henoch-Schönlein purpura (HSP) is a small-vessel vasculitis of autoimmune hypersensitivity, and renin-angiotensin system (RAS) regulates vascular homeostasis and inflammation with activation of cytokine release. Thus, we aimed to investigate the association between HSP and ACE I/D and AGT M235T polymorphisms. Genotyping was determined by allele specific PCR and PCR-RFLP. We obtained a significant difference in genotype distribution (p=0.003) and allele frequencies (p<0.001) of ACE I/D polymorphism between patients and controls, while no significant association was detected in genotype distribution (p> 0.05) and allele frequencies (p> 0.05) of the AGT M235T polymorphism. Risk assessment showed significant risk for HSP in the subjects both with the ID + DD genotype (p=0.019, OR: 2.288, 95% CI: 1.136-4.609) and D allele (OR: D vs. I: 2.0528, 95% CI: 1.3632-3.0912, p=0.001) while no significant risk was obtained for HSP in the subjects both with the MT + TT genotype (p=0.312, OR: 1.3905, 95% T vs. M: 1.065, 95% CI: 0.7326-2.6391) and T allele (OR: patients were stratified by the presence of certain systemic complications of HSP, no significant association was detected with ACE I/D, and AGT M235T polymorphisms. Our findings suggest that ACE I/D polymorphism is significantly associated with HSP susceptibility.
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http://dx.doi.org/10.3233/DMA-2012-120946DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3810110PMC
May 2013

Involution of multicystic dysplastic kidney: is it predictable?

J Pediatr Urol 2013 Jun 9;9(3):344-7. Epub 2012 Jun 9.

Ege University, Faculty of Medicine, Department of Pediatric Surgery, Division of Pediatric Urology, Izmir, Turkey.

Objective: To evaluate the clinical course of multicystic dysplastic kidney (MCDK) and to reveal any criteria indicating spontaneous involution.

Material Methods: Hospital records of patients with MCDK followed in two different institutions in 1994-2009 were reviewed and data were analyzed regarding involution.

Results: Records of 96 patients were reviewed, of whom 46 were diagnosed antenatally and followed for more than 1 year. Fourteen patients had undergone nephrectomy. There was one case of hypertension which resided with nephrectomy. There was no malignancy. Involution rate was 53.6% (15/28) for right-sided and only 16.7% (3/18) for left-sided kidneys. The initial size of the kidney was found to be another predictive parameter for involution. Initial sizes of 43 (15 involuted and 28 non-involuted) kidneys were documented. Mean standard deviation score for involuting and non-involuting kidneys was -3.19 and 3.12, respectively. The chance of involution for a large kidney on the left was zero; however, involution risk for a small right-sided kidney was 67%.

Conclusion: Reviewing a 15-year period of our patient records conveyed data supporting current literature mainly encouraging non-operative management of MCDK. Further studies are required; however, our two objective indicators, the initial size and side of dysplastic kidney, may contribute to the management.
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http://dx.doi.org/10.1016/j.jpurol.2012.04.014DOI Listing
June 2013

Cardiac geometry in children receiving chronic peritoneal dialysis: findings from the International Pediatric Peritoneal Dialysis Network (IPPN) registry.

Clin J Am Soc Nephrol 2011 Aug 7;6(8):1926-33. Epub 2011 Jul 7.

Gazi University Department of Pediatric Nephrology, Besevler, Ankara, 06500 Turkey.

Background And Objectives: Left ventricular hypertrophy (LVH) is an independent risk factor and an intermediate end point of dialysis-associated cardiovascular comorbidity. We utilized a global pediatric registry to assess the prevalence, incidence, and predictors of LVH as well as its evolution in the longitudinal follow-up in dialyzed children.

Design, Setting, Participants, & Measurements: Cross-sectional echocardiographic, clinical, and biochemical data were evaluated in 507 children on peritoneal dialysis (PD), and longitudinal data were evaluated in 128 patients. The 95(th) percentile of LV mass index relative to height age was used to define LVH.

Results: The overall LVH prevalence was 48.1%. In the prospective analysis, the incidence of LVH developing de novo in patients with normal baseline LV mass was 29%, and the incidence of regression from LVH to normal LV mass 40% per year on PD. Transformation to and regression from concentric LV geometry occurred in 36% and 28% of the patients, respectively. Hypertension, high body mass index, use of continuous ambulatory peritoneal dialysis, renal disease other than hypo/dysplasia, and hyperparathyroidism were identified as independent predictors of LVH. The use of renin-angiotensin system (RAS) antagonists and high total fluid output (sum of urine and ultrafiltration) were protective from concentric geometry. The risk of LVH at 1 year was increased by higher systolic BP standard deviation score and reduced in children with renal hypo/dysplasia.

Conclusions: Using height-adjusted left ventricular mass index reference data, LVH is highly prevalent but less common than previously diagnosed in children on PD. Renal hypo/dysplasia is protective from LVH, likely because of lower BP and polyuria. Hypertension, fluid overload, and hyperparathyroidism are modifiable determinants of LVH.
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http://dx.doi.org/10.2215/CJN.05990710DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3359542PMC
August 2011

Contractility reserve in children undergoing dialysis by dobutamine stress echocardiography.

Pediatr Cardiol 2010 Oct 19;31(7):937-43. Epub 2010 May 19.

Department of Pediatric Cardiology, Izmir Dr. Behcet Uz Children's Hospital, Izmir, Turkey.

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.
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http://dx.doi.org/10.1007/s00246-010-9721-xDOI Listing
October 2010

Low-density lipoprotein apheresis by membrane differential filtration (cascade filtration) via arteriovenous fistula performed in children with familial hypercholesterolemia.

Ther Apher Dial 2010 Feb;14(1):87-92

Department of Pediatric Nephrology, Dr Behçet Uz Children's Research and Training Hospital, Izmir, Turkey.

Membrane differential filtration (cascade filtration) is an apheresis technique by which atherogenic lipoproteins can be eliminated from plasma on the basis of particle size. In this study, we aim to discuss the efficacy of low-density lipoprotein (LDL) apheresis performed by providing alternative vascular routes in two siblings with familial hypercholesterolemia who did not respond to medical treatment and diet. Of the two siblings, one was nine years old and the other one was three-and-a-half years old. Of the total of 78 apheresis processes performed, 24 were done via a permanent subclavian catheter, 36 were done via a subsequently provided arteriovenous fistula, and 18 were done via an arteriovenous graft. We observed a mean reduction in the plasma levels of total cholesterol (61.6%), LDL cholesterol (65.5%), and high-density lipoprotein cholesterol (38.6%). We noted that cascade filtration apheresis was effective in decreasing the LDL cholesterol in plasma, and no serious complications were noted. The success of the apheresis program depends on well-functioning blood access. An arteriovenous fistula may be the best route for the long-term treatment of familial hypercholesterolemia, which requires complication-free apheresis treatments.
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http://dx.doi.org/10.1111/j.1744-9987.2009.00795.xDOI Listing
February 2010

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

Nephron Physiol 2009 20;112(4):p53-62. Epub 2009 Jun 20.

Nuffield Department of Clinical Medicine, Academic Endocrine Unit, University of Oxford, and Churchill Hospital, Oxford Centre for Diabetes, Endocrinology and Metabolism, Oxford, UK.

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.
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http://dx.doi.org/10.1159/000225944DOI Listing
January 2010

The metabolic etiology of urolithiasis in Turkish children.

Int Urol Nephrol 2009 31;41(3):453-60. Epub 2009 Jan 31.

Department of Pediatric Nephrology, Dr Behcet Uz Children Hospital, Izmir, Turkey.

Pediatric urolithiasis is an endemic disease, especially in certain developing regions of the world, such as the Far East, and to a certain extent the Middle East and Turkey. The aim of the study is to determine the metabolic etiology and the prevalence of formation of urinary calculi in Turkish pediatric patients with urolithiasis. Seventy-two pediatric patients diagnosed as having urolithiasis were studied from 1999-2005 in Dr. Behcet Uz Child Disease and Surgery Education and Research Hospital Nephrology Department, Izmir, according to their presenting signs and clinical and laboratory findings. The other necessary tests were also applied to detect the etiology of the calculi formation. Of the 72 patients, 50 (69.4%) were male and 22 (30.6%) were female, with ages ranging from 2 to 168 months (mean age 72 +/- 35.7 months), and the male-to-female ratio of patients was 2.3. Twenty-four (33%) of them were diagnosed as having metabolic urolithiasis, 21 (30%) anatomic, 19 (26%) infectious and 8 (11%) idiopathic. The age at which urolithiasis was first diagnosed was found to be low in the metabolic and anatomic etiology groups (P = 0.028). Thirteen patients (18%) with urolithiasis were known to have a family history of stone disease, and in all of them metabolic etiology was considered to be the reason (P < 0.001). In all of the groups, the localization of the stone was found to be the upper urinary system most of the time, and in 17 (24%) with bilateral multiple stones, the etiology was found to be metabolic (P < 0.001). All of the patients were followed up for 3-72 months (mean 29.2 +/- 13.7 months), and four of them (5.5%) had recurrences. In order to prevent renal damage and recurrences in pediatric patients with urolithiasis in Turkey in whom the etiology is mostly metabolic, the illnesses must be investigated very cautiously, and their early diagnosis and treatment modalities must be considered.
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http://dx.doi.org/10.1007/s11255-008-9513-xDOI Listing
August 2009