Urine soluble TLR4 levels may contribute to predict urinary tract infection in children: the UTILISE Study.

BACKGROUND: One of the most common bacterial infections in childhood is urinary tract infection (UTI). Toll-like receptors (TLRs) contribute to immune response against UTI recognizing specific pathogenic agents. Our aim was to determine whether soluble TLR4 (sTLR4), soluble TLR5 (sTLR5) and interleukin 8 (IL-8) can be used as biomarkers to diagnose UTI. We also aimed to reveal the relationship between urine Heat Shock Protein 70 (uHSP70) and those biomarkers investigated in this study. METHODS: A total of 802 children from 37 centers participated in the study. The participants (n = 282) who did not meet the inclusion criteria were excluded from the study. The remaining 520 children, including 191 patients with UTI, 178 patients with non-UTI infections, 50 children with contaminated urine samples, 26 participants with asymptomatic bacteriuria and 75 healthy controls were included in the study. Urine and serum levels of sTLR4, sTLR5 and IL-8 were measured at presentation in all patients and after antibiotic treatment in patients with UTI. RESULTS: Urine sTLR4 was higher in the UTI group than in the other groups. UTI may be predicted using 1.28 ng/mL as cut-off for urine sTLR4 with 68% sensitivity and 65% specificity (AUC = 0.682). In the UTI group, urine sTLR4 levels were significantly higher in pyelonephritis than in cystitis (p < 0.0001). Post-treatment urine sTLR4 levels in the UTI group were significantly lower than pre-treatment values (p < 0.0001). CONCLUSIONS: Urine sTLR4 may be used as a useful biomarker in predicting UTI and subsequent pyelonephritis in children with UTI. A higher resolution version of the Graphical abstract is available as Supplementary information.

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.

Metabolic acidosis is common and associates with disease progression in children with chronic kidney disease.

Recent studies in adult chronic kidney disease (CKD) suggest that metabolic acidosis is associated with faster decline in estimated glomerular filtration rate (eGFR). Alkali therapies improve the course of kidney disease. Here we investigated the prevalence and determinants of abnormal serum bicarbonate values and whether metabolic acidosis may be deleterious to children with CKD. Associations between follow-up serum bicarbonate levels categorized as under 18, 18 to under 22, and 22 or more mmol/l and CKD outcomes in 704 children in the Cardiovascular Comorbidity in Children with CKD Study, a prospective cohort of pediatric patients with CKD stages 3-5, were studied. The eGFR and serum bicarbonate were measured every six months. At baseline, the median eGFR was 27 ml/min/1.73m2 and median serum bicarbonate level 21 mmol/l. During a median follow-up of 3.3 years, the prevalence of metabolic acidosis (serum bicarbonate under 22 mmol/l) was 43%, 60%, and 45% in CKD stages 3, 4, and 5, respectively. In multivariable analysis, the presence of metabolic acidosis as a time-varying covariate was significantly associated with log serum parathyroid hormone through the entire follow-up, but no association with longitudinal growth was found. A total of 211 patients reached the composite endpoint (ESRD or 50% decline in eGFR). In a multivariable Cox model, children with time-varying serum bicarbonate under 18 mmol/l had a significantly higher risk of CKD progression compared to those with a serum bicarbonate of 22 or more mmol/l (adjusted hazard ratio 2.44; 95% confidence interval 1.43-4.15). Thus, metabolic acidosis is a common complication in pediatric patients with CKD and may be a risk factor for secondary hyperparathyroidism and kidney disease progression.

Congenital nephrotic syndrome of NPHS1 associated with cardiac malformation.

Congenital nephrotic syndrome (CNS) is a rare disease inherited as an autosomally recessive trait and defined as proteinuria manifesting at birth or in the first 3 months of life. The classical form is the Finnish type of CNS (CNF), which is caused by mutations in the nephrin gene (NPHS1). The classical findings include prematurity, large placenta and massive proteinuria. Minor cardiac findings have been reported as a minor functional disorder but CNS with major cardiac malformation is rare. Here we report the case of a Turkish child with CNS with small indel mutation (c.614_621delCACCCCGGinsTT) in exon 6 of NPHS1 and also major cardiac malformation who did not develop end-stage renal disease until the age of 5 years.

Comparison of serum cystatin C and creatinine levels in determining glomerular filtration rate in children with stage I to III chronic renal disease.

BACKGROUND: Pediatric studies are relatively scarce on the superiority of cystatin C over creatinine in estimation of glomerular filtration rate (GFR). This study measured cystatin C and serum creatinine levels, and compared GFR estimated from these two parameters in patients with chronic renal disease. METHODS: This prospective, observational, controlled study included 166 patients aged 1-18 years diagnosed with stage I to III chronic renal disease, and 29 age- and sex-matched control subjects. In all patients, GFR was estimated via creatinine clearance, Schwartz formula, Zappitelli 1 and Zappitelli 2 formula and the results were compared using Bland-Altman analysis. RESULTS: Patients and controls did not differ with regard to height, body weight, BMI, serum creatinine and serum cystatin levels, and Schwartz formula-based GFR (p > 0.05). There was a significant relationship between creatinine and cystatin C levels. However, although creatinine levels showed a significant association with age, height, and BMI, cystatin C levels showed no such association. ROC analysis showed that cystatin C performed better than creatinine in detecting low GFR. CONCLUSION: Cystatin C is a more sensitive and feasible indicator than creatinine for the diagnosis of stage I to III chronic renal disease.

Hereditary renal tubular disorders in Turkey: demographic, clinical, and laboratory features.

BACKGROUND: The Turkish Renal Tubular Disorders Working Group aimed to form a patient registry database and gathered demographic, clinical, and laboratory data in various hereditary renal tubular disorders (HRTDs). METHODS: A questionnaire comprising HRTDs was sent to the centers. The cohort was composed of 226 patients (109 girls, 117 boys). RESULTS: The distribution of patients according to HRTD was as follows: 45.6% distal renal tubular acidosis (dRTA), 26.6% proximal RTA (pRTA), 3.5% type IV RTA, 21.7% Bartter's syndrome, and 2.6% Gitelman's syndrome. Cystinosis was the most common cause for renal Fanconi syndrome. Age at diagnosis was between 1 month and 16 years. Overall consanguinity rate was as high as 72%. Rate of affected siblings was 28.5%. pRTA and type IV RTA were more common in males. Most common presenting symptoms were failure to thrive, lack of appetite, and vomiting. Nephropathic cystinosis was the most common HRTD leading to renal failure, followed by dRTA. Hearing loss was present in 23% of patients with dRTA and 6.3% of patients with Bartter's syndrome. No other patient had hearing loss. Convulsions were noted in Bartter's syndrome patients with failure to thrive, especially in those with height below 3%. Polyuria and nephrocalcinosis were more common in dRTA patients with deafness compared with patients without deafness. CONCLUSIONS: This data reflected a high number of HRTDs as a result of high consanguinity rate in Turkey. Our data serve as a database of demographic, clinical, and laboratory features of this rare disease group.

Clinical course of primary focal segmental glomerulosclerosis (FSGS) in Turkish children: a report from the Turkish Pediatric Nephrology FSGS Study Group.

The clinical course of focal segmental glomerulosclerosis (FSGS) is heterogeneous in children. To evaluate the clinical course and the predictors of outcome in Turkish children with primary FSGS, a retrospective study was conducted by the Turkish Pediatric Nephrology Study Group in 14 pediatric nephrology centers. Two hundred twenty-two patients (92 boys, 130 girls, aged 1-16 years) with biopsy-proven primary FSGS were included. One hundred forty-eight patients were followed-up for a median of 51 months (range: 0.26-270). The clinical course was characterized by complete remission in 50 (33.8%), persistent proteinuria in 50 (33.8%) and progression to renal failure in 48 (32.4%) patients. Progression to end-stage renal disease (ESRD) was significantly higher in patients who did not attain remission. Complete remission, partial remission and progress to renal failure were recorded in 37%, 32% and 28%, respectively, of the patients (n = 73) treated with prednisone combined cyclophosphamide/cyclosporine A. However, in patients (n = 33) treated with pulse methyl prednisolone plus oral prednisone (up to 20 months) combined with cyclophosphamide, complete remission in 51.5% and partial remission in 27.3% of the patients were noted. Progression to renal failure was observed in 9.1% of this group of patients. Multivariate analysis showed that only plasma creatinine at presentation was an independent predictive value for outcome. Patients with serum creatinine level higher than 1.5 mg/dl had 6.6 times increased rate of progression to renal failure. Failure to achieve remission is a predictor of renal failure in children with primary FSGS. The use of immunosuppressive treatment in conjunction with prolonged steroid seems beneficial in primary FSGS in children.

Clofarabine-induced capillary leak syndrome in a child with refractory acute lymphoblastic leukemia.

Clofarabine has significant efficiency in children with relapsed or refractory leukemia. In previous pediatric trials, various adverse effects have been described. In this case, we report a child with refractory acute lymphoblastic leukemia who developed fatal capillary leak syndrome during clofarabine therapy.

Hyperprostaglandin E syndrome: use of indomethacin and steroid, and death due to necrotizing enterocolitis and sepsis.

Hyperprostaglandin E syndrome (HPS) is the antenatal variant of Bartter syndrome and characterized by polyhydramnios and preterm delivery in the antenatal period and salt-wasting, isosthenuric or hyposthenuric polyuria, hypercalciuria and nephrocalcinosis in the postnatal period. We report a one-month-old infant with HPS with a 15-year-old sister with Bartter syndrome. The infant's birth weight was 2750 g and she had severe dehydration on the 2nd day of life. She had hypercalcemia, hyponatremia, hypokalemia, metabolic alkalosis and elevated plasma renin and aldosterone levels. We instituted indomethacin therapy accompanied by steroid therapy for hypercalcemia. However, the patient developed abdominal distention on the 30th day, which was due to diffuse pneumatosis in sigmoid colon revealed by a subsequent surgical intervention. Following surgery, the patient developed fever, electrolyte abnormalities and subsequently sepsis. The patient died due to sepsis 10 days after surgery. We conclude that indomethacin and steroid therapy must be used cautiously in infants with HPS.

Treatment approaches for abdominal migration of peritoneal catheter of ventriculoperitoneal shunt.

Migration of peritoneal catheter into the abdominal cavity is rare. We have discussed and presented the treatment options in two cases with accompanying literature. Abdominal migration of peritoneal catheter appears as a result of shunt fracture and disconnection. The complaints on presentation in the abdominal cavity migration of peritoneal catheter are due to shunt dysfunction and peritoneal irritation. The peritoneal catheter with abdominal migration should be removed in cases where abdominal symptoms are present. This procedure may be easily performed laparoscopically with a single mini incision. In some cases, the catheter may cause adhesions to the intra-abdominal organs. Forcefully pulled catheters may result in organ injuries. One should therefore switch to laparotomy in these cases.

Childhood vasculitides in Turkey: a nationwide survey.

AIM: The aims of this study were to evaluate the characteristics of childhood vasculitides and to establish the first registry in Turkey, an eastern Mediterranean country with a white population. PATIENTS AND METHODS: A questionnaire was distributed to the main referral centers asking for the registration of the Henoch-Schönlein purpura (HSP) patients in the last calendar year only and 5 years for other vasculitides. Demographic, clinical, and laboratory data were assessed. RESULTS: Vasculitic diseases were registered from 15 pediatric centers. These centers had a fair representation throughout the country. In the last calendar year, incidences were as follows: HSP 81.6%, Kawasaki disease (KD) 9.0%, childhood polyarteritis nodosa (C-PAN) 5.6%, Takayasu arteritis (TA) 1.5%, Wegener's granulomatosis 0.4%, and Behçet disease 1.9%. There was no clear gender dominance. The mean age was 11.05+/-4.89 years. Acute phase reactants were elevated in almost all, highest figures being in C-PAN. Renal involvement was present in 28.6% of HSP and 53% of the C-PAN patients. Abdominal aorta was involved in all TA patients. Among the C-PAN patients, 25% had microscopic PAN with necrotizing glomerulonephritis; antineutrophil cytoplasmic antibody was positive in those who were studied. Among the patients, 12.5% and 15% had classic PAN and cutaneous PAN, respectively. The remaining majority were classified as systemic C-PAN diagnosed with biopsies and/or angiograms demonstrating small to midsize artery involvement. The overall prognosis was better than reported in adult series. CONCLUSION: This is the largest multicenter study defining the demographic data for childhood vasculitides. The distribution of childhood vasculitides was different in our population where KD is much less frequent, whereas HSP constitutes an overwhelming majority. C-PAN was more frequent as well.

Association of migraine-like headaches with Schimke immuno-osseous dysplasia.

Schimke immuno-osseous dysplasia (SIOD) is characterized by spondyloepiphyseal dysplasia, nephropathy, and T-cell deficiency. SIOD is caused by mutations in the putative chromatin remodeling protein SMARCAL1. We report an 8-year-old boy with SIOD and recurrent, severe, refractory migraine-like headaches. Through a retrospective questionnaire-based study, we found that refractory and severely disabling migraine-like headaches occur in nearly half of SIOD patients. We have also found that the vasodilator minoxidil provided symptomatic relief for one patient. We hypothesize that these headaches may arise from an intrinsic vascular, neuroimmune, or neurovascular defect resulting from loss of SMARCAL1 function.