Kidney disease profile and encountered problems during follow-up in Syrian refugee children: a multicenter retrospective study.

BACKGROUND: Children are one of the most vulnerable groups in conflict zones, especially those with chronic diseases. This study aimed to investigate kidney disease profiles and problems during follow-up in a population of Syrian refugee children residing in Turkey. METHODS: Syrian refugee children aged between 0 and 18 years were included in the study. Demographic data, diagnosis, particular interventions due to nephrological problems, and problems encountered during follow-up were obtained from all participating pediatric nephrology centers. RESULTS: Data from 633 children from 22 pediatric nephrology centers were included. Mean age of the children was 94.8 ± 61.7 months and 375 were male (59%). 57.7% had parental consanguinity and 23.3% had a close relative(s) with kidney disease. The most common kidney diseases were congenital anomalies of the kidney and urinary tract (CAKUT) (31.0%), glomerular disease (19.9%), chronic kidney disease (CKD) (14.8%), and urolithiasis (10.7%). Frequent reasons for CAKUT were nonobstructive hydronephrosis (23.0%), vesico-ureteral reflux (18.4%), and neurogenic bladder (15.8%). The most common etiology of glomerular diseases was nephrotic syndrome (69%). Ninety-four children had CKD, and 58 children were on chronic dialysis. Six children had kidney transplantation. Surgical intervention was performed on 111 patients. The language barrier, lack of medical records, and frequent disruptions in periodic follow-ups were the main problems noted. CONCLUSIONS: CAKUT, glomerular disease, and CKD were highly prevalent in Syrian refugee children. Knowing the frequency of chronic diseases and the problems encountered in refugees would facilitate better treatment options and preventive measures.

Predictors of poor kidney outcome in children with C3 glomerulopathy.

BACKGROUND: C3 glomerulopathy (C3G) is characterized by heterogeneous clinical presentation, outcome, and predominant C3 accumulation in glomeruli without significant IgG. There is scarce outcome data regarding childhood C3G. We describe clinical and pathological features, treatment and outcomes, and risk factors for progression to chronic kidney disease stage 5 (CKD5) in the largest pediatric series with biopsy-proven C3G. METHODS: Sixty pediatric patients with C3G from 21 referral centers in Turkey were included in this retrospective study. Patients were categorized according to CKD stage at last visit as CKD5 or non-CKD5. Demographic data, clinicopathologic findings, treatment, and outcome data were compared and possible risk factors for CKD5 progression determined using Cox proportional hazards model. RESULTS: Mean age at diagnosis was 10.6 ± 3.0 years and follow-up time 48.3 ± 36.3 months. Almost half the patients had gross hematuria and hypertension at diagnosis. Nephritic-nephrotic syndrome was the commonest presenting feature (41.6%) and 1/5 of patients presented with nephrotic syndrome. Membranoproliferative glomerulonephritis was the leading injury pattern, while 40 patients had only C3 staining. Patients with DDD had significantly lower baseline serum albumin compared with C3GN. Eighteen patients received eculizumab. Clinical remission was achieved in 68.3%. At last follow-up, 10 patients (16.6%) developed CKD5: they had lower baseline eGFR and albumin and higher frequency of nephrotic syndrome and dialysis requirement than non-CKD5 patients. Lower serum albumin and eGFR at diagnosis were independent predictors for CKD5 development. CONCLUSIONS: Children with C3G who have impaired kidney function and hypoalbuminemia at diagnosis should be carefully monitored for risk of progression to CKD5. Graphical abstract.

Influenza and pneumococcus vaccination rates in pediatric dialysis patients in Europe: recommendations vs reality A European Pediatric Dialysis Working Group and European Society for Pediatric Nephrology Dialysis Working Group study

Background/aim: Children on dialysis are under increased risk of influenza and invasive pneumococcal disease. Although vaccination against these microorganisms are recommended in dialysis patients and despite the fact that these vaccines can reduce disease burden and rates of hospitalization due to infection, vaccination rates are below expected and desired. We aimed to evaluate influenza and pneumococcal vaccination and infection rates in European pediatric dialysis centers. Materials and methods: In 16 centers from 11 countries, 357 pediatric dialysis patients were evaluated retrospectively during 1 year of observation period between 01.01.2014 and 01.01.2015. Results: In all centers, vaccination policy included immunization of dialysis patients with inactive influenza vaccine and pneumococcal conjugate vaccine (PCV). Fifty percent of the centers recommended pneumococcal polysaccharide vaccine following routine PCV series. A significantly higher pneumococcal vaccination rate (43.9%) was seen in peritoneal dialysis (PD) patients compared to those on hemodialysis (HD) (32.9%) (p = 0.035), while the rates for influenza were similar (42.4% and 46.1% respectively, p = 0.496). Among all dialysis patients, 2.2% (n = 8) developed pneumonia and 6.4% (n = 23) was infected by Influenza. Pneumococcic pneumonia rate was 5% for 140 patients who received antipneumococcal vaccine, while only one pneumonia episode was recorded out of 217 unvaccinated patients (p = 0.007). The influenza virus infection rates were similar for patients vaccinated and nonvaccinated (7 % and 6 %, respectively). Conclusions: Although influenza and pneumococcal vaccines are highly recommended in pediatric dialysis patients, vaccination rates were lower than expected. Pneumococcal vaccination rates were higher in PD compared to the patients on HD. The rate of children with influenza infection was higher than pneumonia. The efficacy of influenza and pneumococcal vaccines was highlighted by the low infection rates. Higher pneumonia rates in patients vaccinated against pneumococcus compared to unvaccinated ones might be due to coexisting risk factors.

Evaluation of phenotypic and genotypic features of children with distal kidney tubular acidosis.

BACKGROUND: The present study aimed to assess genotype-phenotype correlations with long-term prognosis in children with distal kidney tubular acidosis (dKTA). The kidney function of children with dKTA could be impaired in the long-term. METHODS: Thirty-one children with dKTA from 23 families were included in the present study. Demographic features, growth parameters, clinical manifestations, follow-up results, and genetic analysis results of the patients were recorded. RESULTS: Eighteen children (58.1%) were male. The median age at diagnosis was 3 months. The median follow-up period was 77 months and the longest was 23.5 years. Eight (28.8%) patients had chronic kidney disease (CKD) stage 2 or 3. Three patients aged 24, 23, and 19 years had CKD stage 3 with an estimated glomerular filtration rate of 54, 57, and 48 mL/min/1.73 m2, respectively. Thirteen patients had mutations in the ATP6V0A4 gene, eight had mutations in the ATP6V1B1 gene, and three had mutations in the SLC4A1 gene. There was no significant correlation between molecular diagnosis and CKD. Growth retardation with a height below a standard deviation (SD) score of - 2 was found in 14 patients (45.1%) at the time of diagnosis. The mean height SD score at the last visit was significantly higher in patients who had adequate metabolic control at > 75% of all visits as compared with that in patients who did not. CONCLUSION: Patients with dKTA usually have a good clinical prognosis in childhood with appropriate treatment; however, dRTA is characterized by deterioration of kidney function in adulthood, particularly after puberty.

Clinical manifestations and outcomes of 420 children with Henoch Schönlein Purpura from a single referral center from Turkey: A three-year experience.

Objectives: Henoch Schönlein Purpura (HSP) is the most common systemic vasculitis in childhood. We aimed to evaluate the clinical features, seasonal variation, treatment outcomes and the possible predicting factors related to outcome among a large cohort of pediatric HSP patients.Methods: We conducted a medical record review study between July 2016 and January 2019 and evaluated the clinical manifestations and potential risk factors for severe gastrointestinal (GI) involvement, biopsy-proven nephritis and relapses.Results: The study included 420 HSP patients, of which the mean age at diagnosis was 7.68 ± 3.15 years. Clinical manifestations were arthralgia and/or arthritis (n = 244, 58.1%), abdominal pain (n = 235, 56%), subcutaneous edema (n = 163, 38.8%), and renal involvement (n = 125, 29.8%). Disease recurred for at least once, in 69 (16.4%) patients and colchicine treatment yielded a favorable response in 11 of 12 relapsing patients, who did not respond to ibuprofen or steroids. Frequencies of renal involvement and biopsy-proven nephritis were higher in patients with severe GI involvement. Besides, patients with biopsy-proven nephritis had higher rates of abdominal pain, intussusception, severe GI involvement, and systemic steroid administration.Conclusion: We speculate that renal involvement, biopsy-proven nephritis and severe GI involvement can be related to each other. Colchicine may be effective in patients with relapsing disease.

Treatment and long-term outcome in primary distal renal tubular acidosis.

BACKGROUND: Primary distal renal tubular acidosis (dRTA) is a rare disorder, and we aimed to gather data on treatment and long-term outcome. METHODS: We contacted paediatric and adult nephrologists through European professional organizations. Responding clinicians entered demographic, biochemical, genetic and clinical data in an online form. RESULTS: Adequate data were collected on 340 patients (29 countries, female 52%). Mutation testing had been performed on 206 patients (61%); pathogenic mutations were identified in 170 patients (83%). The median (range) presentation age was 0.5 (0-54) years and age at last follow-up was 11.0 (0-70.0) years. Adult height was slightly below average with a mean (SD score) of -0.57 (±1.16). There was an increased prevalence of chronic kidney disease (CKD) Stage ≥2 in children (35%) and adults (82%). Nephrocalcinosis was reported in 88%. Nephrolithiasis was more common with SLC4A1 mutations (42% versus 21%). Thirty-six percent had hearing loss, particularly in ATP6V1B1 (88%). The median (interquartile range) prescribed dose of alkali (mEq/kg/day) was 1.9 (1.2-3.3). Adequate metabolic control (normal plasma bicarbonate and normocalciuria) was achieved in 158 patients (51%), more commonly in countries with higher gross domestic product (67% versus 23%), and was associated with higher height and estimated glomerular filtration rate. CONCLUSION: Long-term follow-up from this large dRTA cohort shows an overall favourable outcome with normal adult height for most and no patient with CKD Stage 5. However, 82% of adult patients have CKD Stages 2-4. Importance of adequate metabolic control was highlighted by better growth and renal function but was achieved in only half of patients.

Clinical and histopathological prognostic factors affecting the renal outcomes in childhood ANCA-associated vasculitis.

OBJECTIVE: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are very rare in childhood with an increased risk of morbidity and mortality. We aimed to evaluate renal prognostic factors in childhood AAV from the perspective of ANCA serotype, histopathological classification, and five-factor score (FFS). METHODS: Pediatric AAV patients from 11 referral centers in Turkey had been included to the study. The demographics, clinical findings, AAV subtypes, outcomes, and FFS were evaluated retrospectively. Kidney biopsies were classified histopathologically. RESULTS: Totally, 39 patients were enrolled in the study. Among all patients, 74.4% had renal involvement, 56.4% ear-throat-nose involvement, and 51.3% had musculoskeletal involvement. Proteinase 3 (PR3)-ANCA was positive in 48.7%, and myeloperoxidase (MPO)-ANCA was positive in 30.8%. 69.2% of patients had impaired renal function, and 28.2% had progressed to end-stage renal disease (ESRD) during the follow-up. At the time of diagnosis, FFS was ≥ 2 in 53.8%. The most common histopathologic classifications were as follows: crescentic type in 40.7% and sclerotic type in 25.9%. Gastrointestinal and renal involvement, MPO-ANCA positivity, serum creatinine levels, and impaired renal function during the follow-up were significantly higher in patients with FFS ≥ 2, compared to patients with FFS < 2. Patients with FFS ≥ 2 had more common crescentic, mixed and sclerotic histopathologic findings in biopsies. By logistic regression analysis forward method, the strongest single-risk factor among all the parameters was the initial level of creatinine in patients with ESRD, compared to the other patients (p = 0,007). CONCLUSIONS: Evaluation of the FFS, ANCA serology, and the creatinine levels may help to predict renal prognosis.

Risk Factors for Early Dialysis Dependency in Autosomal Recessive Polycystic Kidney Disease.

OBJECTIVE: To identify prenatal, perinatal, and postnatal risk factors for dialysis within the first year of life in children with autosomal recessive polycystic kidney disease (ARPKD) as a basis for parental counseling after prenatal and perinatal diagnosis. STUDY DESIGN: A dataset comprising 385 patients from the ARegPKD international registry study was analyzed for potential risk markers for dialysis during the first year of life. RESULTS: Thirty-six out of 385 children (9.4%) commenced dialysis in the first year of life. According to multivariable Cox regression analysis, the presence of oligohydramnios or anhydramnios, prenatal kidney enlargement, a low Apgar score, and the need for postnatal breathing support were independently associated with an increased hazard ratio for requiring dialysis within the first year of life. The increased risk associated with Apgar score and perinatal assisted breathing was time-dependent and vanished after 5 and 8 months of life, respectively. The predicted probabilities for early dialysis varied from 1.5% (95% CI, 0.5%-4.1%) for patients with ARPKD with no prenatal sonographic abnormalities to 32.3% (95% CI, 22.2%-44.5%) in cases of documented oligohydramnios or anhydramnios, renal cysts, and enlarged kidneys. CONCLUSIONS: This study, which identified risk factors associated with onset of dialysis in ARPKD in the first year of life, may be helpful in prenatal parental counseling in cases of suspected ARPKD.

Extra-Renal manifestations of atypical hemolytic uremic syndrome in children.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is a chronic disease characterized by thrombotic microangiopathy and a high risk of end-stage kidney disease. Dysregulation and/or excessive activation of the complement system results in thrombotic microangiopathy. Interest in extrarenal manifestations of aHUS is increasing. This study aimed to determine the clinical characteristics of patients with extrarenal manifestations of aHUS in childhood. METHODS: This study included 70 children with extrarenal manifestations of HUS from the national Turkish aHUS Registry. The demographics, clinical characteristics, genetic test results, all treatments, and renal/hematologic status of aHUS patients with extrarenal involvement were recorded. RESULTS: The most common extrarenal manifestation was neurological system involvement (n = 46 [27.2%]), followed by gastrointestinal (n = 20 [11.8%]), cardiovascular (n = 12 [7%]), and respiratory (n = 12 [7%]) involvement. The patients with neurological involvement had a higher mortality rate and a lower estimated glomerular filtration rate (eGFR) than the other patients at last follow-up. Eculizumab (with or without plasma exchange/plasma infusion) treatment increased the renal and hematologic recovery rates. CONCLUSIONS: The most common and serious extrarenal manifestation of aHUS is neurological involvement and treatment outcome findings presented herein are important to all relevant clinicians.

The predictive value of resistive index obtained by Doppler ultrasonography early after renal transplantation on long-term allograft function.

DUSG is a useful diagnostic tool for the follow-up of renal transplant recipients. The measurement of intrarenal arterial RI by DUSG has been proven to predict short-term AF. The aim of the study was to evaluate the predictive value of DUSG performed during the early after RTx on long-term AF. Seventy patients were enrolled into study. DUSG was performed at third and seventh days after RTx. Patients were divided into two groups according to rate of recovery of graft function as patients with normal graft function and abnormal graft function. Although the RI values were correlated with the AF early after transplantation, they were not correlated with long-term AF. However, the rate of recovery of graft function at early period after RTx was correlated with creatinine level at first year and with glomerular filtration rate at first year and last visit. Although the RI has no predictive value for long-term AF, the rate of recovery of graft function at early post-transplantation period has predictive value for long-term AF; patients with higher RI values early after RTx should be followed carefully for the development of chronic allograft injury.

More than tubular dysfunction: cystinosis and kidney outcomes.

BACKGROUND: Cystinosis is a lysosomal storage disease that affects many tissues. Its prognosis depends predominantly on kidney involvement. Cystinosis has three clinical forms: nephropathic infantile, nephropathic juvenile and non-nephropathic adult. Proximal tubular dysfunction is prominent in the infantile form, whereas a combination of glomerular and tubular alterations are observed in the juvenile form. METHODS: Thirty-six children with nephropathic cystinosis were included in the study. Clinical features, molecular genetic diagnoses, and kidney outcomes of the patients were evaluated. RESULTS: Twenty-one children (58.3%) were male. The median age at diagnosis was 18.5 months. Twenty-eight patients (77.8%) had infantile nephropathic cystinosis, while eight (22.2%) had juvenile nephropathic cystinosis. An acute rapid deterioration of the kidney function with proteinuria, hypoalbuminemia, and nephrotic syndrome, was observed in 37.5% of patients with the juvenile form. The mean estimated glomerular filtration rate (eGFR) was 82.31 ± 37.45 ml/min/1.73m2 at diagnosis and 63.10 ± 54.60 ml/min/1.73m2 at the last visit (p = 0.01). Six patients (16.6%) had kidney replacement therapy (KRT) at the last visit. The median age of patients with kidney failure was 122 months. Patients with a spot urine protein/creatinine ratio < 6 mg/mg at the time of diagnosis had better kidney outcomes (p = 0.01). The most common allele was c.451A>G (32.6%). The patients with the most common mutation tended to have higher mean eGFR and lower leukocyte cystine levels than patients with other mutations. CONCLUSION: Glomerulonephritis may be a frequent finding in addition to the well-known tubular dysfunction in patients with cystinosis. Furthermore, our results highlight that the presence of severe proteinuria at the time of diagnosis is a relevant prognostic factor for kidney survival.

Risk Assessment for BK Virus-Associated Hemorrhagic Cystitis After Pediatric Hematopoietic Stem Cell Transplant: A Single-Center Retrospective Cross-Sectional Study.

OBJECTIVES: BK virus-associated hemorrhagic cystitis is a common complication of allogeneic hematopoietic stem cell transplant. It is known to be associated with cyclophosphamide therapy and the intensity of the conditioning regimen as well as infection with the BK virus. Data are limited for BK virus-associated hemorrhagic cystitis in pediatric recipients of allogeneic hematopoietic stem cell transplant. Therefore, we aimed to identify the risk factors and etiology of BK virus-associated hemorrhagic cystitis and determine the factors that may improve the treatment efficacy. MATERIALS AND METHODS: Data from recipients of allogeneic hematopoietic stem cell transplant were retrospectively analyzed. These data included information about age, sex, underlying disease, the details of ablative conditioning, graft-versus-host disease prophylaxis, donor type, stem cell source, history of acute graft-versus-host disease, and cytomegalovirus reactivation. RESULTS: A total of 50 patients developed BK virusassociated hemorrhagic cystitis among 334 patients. Symptoms associated with BK virus-associated hemorrhagic cystitis manifested an average of 45.3 days after transplant. Most of the patients had grade 2 and grade 3 hemorrhagic cystitis. Risk factor analysis revealed that haploidentical donor type, treatment with busulfan and cyclophosphamide as part of conditioning regimen, and history of total body irradiation increased the risk of BK virus-associated hemorrhagic cystitis in the pediatric recipient population. CONCLUSIONS: We found that, despite current conditioning regimens, BK virus-associated infection still leads to a considerable incidence rate of hemorrhagic cystitis in pediatric recipients of allogeneic hematopoietic stem cell transplant. Patients with a haploidentical donor and a history of busulfan and cyclophosphamide treatment or total body irradiation had a higher risk of BK virus-associated hemorrhagic cystitis. Thus, we suggest that patients with these factors should be followed closely after allogeneic hematopoietic stem cell transplant.

Parvovirus B19-induced multisystemic vasculitis and acute endocapillary proliferative glomerulonephritis in a child.

A 10-year-old girl was admitted with fever, cough, maculopapular rash, hemoptysis, dark-colored urine, edema, multiple lymphadenopathies, and hepatosplenomegaly. She developed acute glomerulonephritis during the course of these complex clinical features. Laboratory data showed hematuria, proteinuria, and hypocomplementemia. Serological tests showed positive human parvovirus B19 (HPVB19)-specific immunoglobin M (IgM) and HPVB19 DNA was detected in the patient's serum using polymerase chain reaction (PCR). Renal biopsy revealed acute endocapillary proliferative glomerulonephritis (AEPGN) with coarse granular C3 depositions in a "starry sky pattern," which is more peculiar to poststreptococcal glomerulonephritis. Electron microscopy showed subendothelial and small hump-shaped subepithelial electron-dense deposits in glomerular capillary walls. There was no evidence of either any mycobacterial, staphylococcal, or streptococcal infection, and the diagnosis of Goodpasture syndrome and connective tissue disorders was excluded during clinical and laboratory investigations. A diagnosis of HPVB19-induced pleuropneumonitis and glomerulonephritis was made. Through a literature search there was no documented pediatric case of AEPGN induced by HPVB19, and this case represents, to our knowledge, the first time that a direct relationship between parvovirus infection and AEPGN has been demonstrated in a child.

From infancy to adulthood: challenges in congenital nephrogenic diabetes insipidus.

Objectives Congenital nephrogenic diabetes insipidus (NDI) is a rare hereditary disorder which is characterized by unresponsiveness to arginine vasopressin (AVP) in collecting ducts and leads to polyuria and polydipsia. The wide clinical spectrum of congenital NDI can cause difficulties in early diagnosis. We aimed to evaluate clinical prognosis of children with congenital NDI in long-term period. Methods Nineteen children with congenital NDI followed up in Pediatric Nephrology Department were enrolled to the study. This study is a single-center retrospective study, which reports clinical follow-up and genetic results of children with congenital NDI. Results Presenting symptoms of patients were mostly dehydration and fever due to polyuria and polydipsia. Four male patients had bilateral nonobstructive hydroureteronephrosis (HUN) and neurogenic bladder which requires clean intermittent catheterization (CIC). One patient had intracranial calcification which is a rarely seen complication in congenital NDI due to recurrent hypernatremic dehydration and severe brain dehydration. The causative mutations were identified in all patients. The identified mutations in six of them (31.6%) were hemizygous mutations in AVPR2 gene and homozygous mutations of AQP2 gene in the rest 13 cases (68.4%). More than that, four of these mutations (two in AVPR2 and two in AQP2) were novel mutations. Noncompliance with the treatments is associated with high risk of morbidity due to neurogenic bladder and chronic kidney disease (CKD). Conclusions The prognosis of congenital NDI is good when diagnosis can be made early and treatment is started immediately. Genetic counseling and prenatal testing for hereditary diseases are recommended especially in regions with relatively higher rates of consanguineous marriages.