[Pyroglutamic acidemia associated with acetaminophen]. / Acidosis piroglutámica asociada a paracetamol.

We report a case of pyroglutamic acidemia probably related to acetaminophen administration. A 16-month boy recovering from hemolytic uremic syndrome abruptly developed unexplained high anion gap metabolic acidosis requiring hemodialysis. Septic shock, lactic acidosis and salicylate intoxication were ruled out. Betahydroxybutyrate and acetoacetate levels were within the normal range. No osmolarity gap or high amino acid levels were found. Urine and blood pyroglutamic acid levels were 392 mmol/mol creatinine (reference range: 9-55) and 9.8 mmol/L (reference range<0.16), respectively. The patient was receiving acetaminophen. We conclude that pyroglutamic acidosis should be considered in patients receiving acetaminophen who abruptly develop high anion gap metabolic acidosis not attributable to more common causes.

Renal transplantation in children with nephrotic syndrome in the first year of life.

OBJECTIVE: The aim of this work was to analyze the evolution of the 1st renal transplantation in children with nephrotic syndrome in the 1st year of life (NSFL). METHODS: In this retrospective study of 15 patients (8 women and 7 men) with NSFL receiving transplants from 1989 to 2013, 9 had NS of Finnish type, 4 diffuse mesangial sclerosis, 1 minimal changes, and 1 collapsing glomerulopathy. We analyzed the clinical and analytic situation at 4 time points: before dialysis, before transplantation, 3 months after transplantation, and long-term evolution. RESULTS: Mean follow-up was 72.8 months (range, 1 month to 16.9 years); mean age at diagnosis was 2.21 months (range, 0-8.2 months); mean age at onset of replacement therapy was 22.9 ± 16.4 months (range, 3.8-55.4 months); and mean time on dialysis was 14.9 months (range, 2-44 months). Age at transplantation was 3.1 years (range, 1.8 to 7.7 years), with 6 living-donor transplantations (LDTs) and 9 cadaveric (CDTs). Ten patients required nephrectomy before transplantation (9 bilateral) to control proteinuria after 3.1 ± 3.8 months on dialysis, 1 during transplantation, and 3 after transplantation (2 persistent proteinuria, 1 hypertension). Mean time on dialysis for LDTs was 5.4 ± 2.7 months versus 13.2 ± 6.9 months for CDTs (P < .005). Mean age of cadaveric donors was 6.2 ± 2.4 years and that of living donors 35.5 ± 7.9 years. As complications, there was 1 bleeding from venous anastomosis and 1 urinary leakage after surgery. After 6 ± 5.2 years of evolution, actuarial survival at both 1 and 7 years was 92.9%. One graft was lost owing to acute rejection 1 month after transplantation and 2 others owing to chronic rejection >9 years after transplantation. None had disease recurrence. CONCLUSIONS: Short-term complications did not differ from the rest of population if transplantation occurred with standard albumin levels, for which most required pre-transplantation nephrectomy because dialysis failed to reduce proteinuria.

BK virus infection in pediatric renal transplantation.

BACKGROUND: Polyomavirus BK (BKV) is a common complication after renal transplantation and an important cause of graft loss. The purpose of this study was to determine the incidence of BKV infection (viremia) in our population and to describe clinical features, global outcomes, and potential correlations with clinical or epidemiologic factors. METHODS: This retrospective single-center study included 84 pediatric recipients of kidney transplantation from January 2006 to September 2012. BKV infection screening consisted of periodic determination of decoy cells in urine samples, confirmed by means of quantitative polymerase chain reaction test in blood. RESULTS: Twenty-two patients (26%) developed BKV viremia. BKV replication appeared early after renal transplantation (median, 2 months). One-third of patients remained asymptomatic, and 27% presented elevated serum creatinine. Immunosuppression was reduced in 90% of patients, and 83% achieved clearance of viremia within 6 months. There was only 1 case of histologically confirmed BKV nephropathy, which evolved to graft loss despite leflunomide, intravenous immunoglobulins, and mycophenolate discontinuation. Risk of BKV viremia was associated with younger age at transplantation (5.9 y vs 10.9 years; P = .001) and cadaveric donor (relative risk, 3.2; P < .05). BKV infection did not affect short-term renal function and graft survival. CONCLUSIONS: BKV viremia is very common in the pediatric renal transplant population, especially in younger children and in those receiving a kidney from cadaveric donors. It develops in the 1st months after transplantation. Reduction of immunosuppression seems to be a good therapeutic option, with high rates of clearance of the infection, although the only patient with confirmed BKV nephropathy had poor outcome.

Preemptive treatment with oral ganciclovir for pediatric renal transplantation.

This prospective study examines 42 children in the first year after renal transplantation. They all received intravenous ganciclovir prophylaxis for cytomegalovirus in the immediate post-transplant period. Quantitative antigenemia (pp68) determinations and blood, urine and throat cultures were done on a scheduled basis to detect cytomegalovirus. Infection was detected in 22 children (52.4%) within an average 44.31 +/- 27.38 days; 5/22 were symptomatic. The antigenemia was positive (+) in all the infected patients, and so were blood culture in 68.2%, urine culture in 59.1% and throat culture in 31.8%. A positive antigenemia was the earliest finding in all cases but 1. The 5 children with clinical symptoms received intravenous ganciclovir. Asymptomatic infected children received oral ganciclovir at an average dose of 47.64 +/- 8.10 mg/kg/day (median 46.58 (range 33-58.7) mg/kg/day) for an average of 58.47 +/- 27.76 days (median 58 (range 26-211) days). No patient developed disease or ganciclovir resistance during the treatment. No patient presented acute graft rejection or renal dysfunction and their glomerular filtrate rate at 1 year was similar to that of noninfected children (90.38 +/- 26.51 vs. 93.93 +/- 36.24 ml/min/1.73 m2). We conclude that preemptive treatment with oral ganciclovir is useful and safe in children with renal transplantation and that monitoring blood antigenemia is a sensitive and early method to detect and control CMV infection.

[Nitrogen balance in adolescent patients with chronic renal insufficiency]. / Estudio de balance nitrogenado y estadio puberal en pacientes con insuficiencia renal crónica.

UNLABELLED: Protein restriction in patients with chronic renal failure may be potentially beneficial, however the dangers in growing children of such restrictions must be considered. We analyzed the nitrogen balance in 60 chronic renal failure children (47 male y 13 female) Group A: 36 preadolescents. GFR was 54.5 +/- 25.6 ml/min/1.73 m2. Group B: 24 adolescents. GFR 52.7 +/- 25.4 ml/min/1.73 m2. RESULTS: 55% of patients had a negative balance. 72% preadolescents and 17% of adolescents had positive nitrogen balance A good correlation was found between the range of energy and protein intake and nitrogen balance. CONCLUSIONS: 1. A good correlation was found between nitrogen balance and the range of energy and protein intake but no correlation with the renal function degree. 2. Adolescents had nitrogen balance negative. 3. It is necessary turn-over protein studies in this patients to know the requirements in children with chronic renal failure.

[Neonatal pelvic ectasia: long-term outcome and association with ureterovesical anomalies]. / Ectasia piélica neonatal: evolución a largo plazo y asociación a anomalías vesicoureterales.

OBJECTIVE: To analyze the outcome of neonatal pelvic ectasia (PE) and the association between this entity and vesicoureteral reflux and/or other urinary tract abnormalities. PATIENTS AND METHODS: We performed a retrospective study of 255 children (205 boys, 50 girls) with an ultrasonographic diagnosis of PE in the first month of life. The initial ultrasonographic examination was indicated by urinary tract infection in 30 neonates, abnormalities in the prenatal ultrasonographic examination in 150 and by other reasons in 75. Pelvic ectasia was classified in four stages according to anteroposterior pelvic diameter: I < 1 cm, II 1-1.5 cm, III 1.6-2 cm, and IV > 2 cm. RESULTS: Pelvic ectasia was bilateral in 153 children (60 %) and unilateral in 102 (left side in 81.4 % and right side in 18.6 %). Stage I was found in 75.49 %, stage II in 20.34 %, stage III in 3.9 % and stage IV in 0.24 %. The mean follow-up was 32.6 +/- 25.2 months. At the end of the first year, the results of renal ultrasound were normal in 70.2 % of left-sided PE and in 55.9 % of right-sided PE, but 46 patients (18 %) showed worsening of PE between the first and second ultrasound scans. Voiding cystourethrography was performed in 79.6 % of the children and some abnormalities were found in 50 (24.6 %): urethral dilatations in two patients and vesicoureteral reflux in 48. No correlation was found between vesicoureteral reflux and the degree of ectasia (74 % had an anteroposterior diameter of < or = 1 cm). Urinary tract infection was present in 24.3 % of the children and 13 required surgery (eight pyeloplasties, four urethral reimplantations and two resections of type III urethral valves). CONCLUSIONS: Neonatal PE was more prevalent in boys (4:1) and was more frequently located on the left side in both sexes. Associated vesicourethral reflux was found in 23.64 % with no correlation between the degree of dilation and the presence or degree of reflux. Consequently, cystourethrography should be performed in any child with pelvic ectasia, regardless of stage, side or sex.

[Midterm evolution in the uropathy patient receiving a kidney transplant]. / Evolución a medio plazo del uropata como receptor de trasplante renal.

The outcome of renal transplantation was examined in 17 pediatric patients, whose primary renal disease was uropathy. The results indicate that the outcome of renal transplantation in patients with posterior urethral valves, reflux nephropathy, neurogenic bladder or bilateral ureterocele is similar to that the other transplant recipients. Urologic complications will not occur with increased frequency. Allograft survival rate during a period of four years is comparable to that of our entire transplant population.

[Results of kidney transplantation in children weighing less than 11 kilograms]. / Resultados del trasplante renal en niños con un peso inferior a 11 kilogramos.

Weigh and age are risk factors of graft failure. The aim of the study is to review the characteristics and the outcome of cadaver renal transplant in children weighing less than 11 Kg. From 1985 to 1999 10 cadaver renal transplant were performed in 10 children (7 boys and 3 girls). Primary renal disease were renal dysplasia(3), posterior urethral valves(5) and congenital nephrotic syndrome(2). All except two suffered end stage disease from birth. The cadaver donor age ranged from 4 to 45 years (mean 12.3). Cold ischaemia time was 14 to 30 hours (median 22.8 h). Grafts were placed extraperitoneally in the iliac fossa in all patients and special care was taken in aggressive intravascular volume expansion. In the first 5 children initial immunosuppression consisted of CyA, Pd and Aza. After 1991, the other five received sequential induction therapy with polyclonal antibodies and triple therapy (CyA, Pd, Aza). Renal function was evaluated as GFR yearly by Swartz formula and the actuarial and graft survival rates were obtained by Kaplan-Meier analysis. Patient survival was 90% at 1 and 10 years. Graft survival was 80% at 1 and 5 years; it decreased to 64% at 7 years. Seven continue with their first graft and the mean follow-up time is 6.6 years. Their renal function measured by the mean of GFR yearly decreased lightly from 102 ml/min/1.73 m2 at 1 year to 87.6 ml/min/1.73 m2 at 5 years. A successful patient and graft survival can be achieved in young receiving kidneys and small reciepients can improve their physical and mental development after transplantation.

[Consensus document: recommendations for the use of equations to estimate glomerular filtration rate in children]. / Documento de consenso: recomendaciones sobre la utilización de ecuaciones para la estimación del filtrado glomerular en niños.

The appearance of the K/DOQI guidelines in 2002 on the definition, evaluation and staging of chronic kidney disease (CKD) have led to a major change in how to assess renal function in adults and children. These guidelines, recently updated, recommended that the study of renal function is based, not only on measuring the serum creatinine concentration, but this must be accompanied by the estimation of glomerular filtration rate (GFR) obtained by an equation. However, the implementation of this recommendation in the clinical laboratory reports in the paediatric population has been negligible. Numerous studies have appeared in recent years on the importance of screening and monitoring of patients with CKD, the emergence of new equations for estimating GFR, and advances in clinical laboratories regarding the methods for measuring plasma creatinine and cystatin C, determined by the collaboration between the departments of paediatrics and clinical laboratories to establish recommendations based on the best scientific evidence on the use of equations to estimate GFR in this population. The purpose of this document is to provide recommendations on the evaluation of renal function and the use of equations to estimate GFR in children from birth to 18 years of age. The recipients of these recommendations are paediatricians, nephrologists, clinical biochemistry, clinical analysts, and all health professionals involved in the study and evaluation of renal function in this group of patients.

Bilateral laparoscopic nephrectomy with simultaneous peritoneal dialysis catheter implantation.

Bilateral nephrectomy prior to transplantation is indicated in some patients with end-stage renal disease. The indications for bilateral nephrectomy include persistent heavy proteinuria, refractory hypertension, and urinary tract infections. We report an eight-month-old baby with male pseudohermaphroditism and renal failure secondary to diffuse mesangial sclerosis. While awaiting renal transplantation, dialysis became necessary and the child presented standard drug therapy-resistant hypertension. A bilateral nephrectomy was performed simultaneously to peritoneal dialysis catheter implantation by using laparoscopy. At the present time, the patient is doing well with ambulatory dialysis and all antihypertensive medication has been discontinued. We recommend this technique in children who require bilateral nephrectomy and peritoneal dialyisis. Not only is it somewhat less aggressive than traditional open surgery, but it also reduces post-operative pain, allows earlier initiation of peritoneal dialysis, and improves cosmetic appearance.

[value of bone densitometry in pediatric renal transplantation]. / Valor de la densitometría ósea en el trasplante renal pediátrico.

OBJECTIVE: Renal transplantation improves many bone abnormalities inherent to chronic renal insufficiency, but also introduces new deleterious factors, especially those related to immunosuppressive drugs. We have studied the bone mineral content of 40 pediatric renal transplant recipients; moreover, we have analyzed its possible relationships with phosphorous-calcium metabolism, graft function and duration, steroid treatment and growth. PATIENTS AND METHODS: Bone mineral content was measured by dual energy X-ray absorptiometry (DEXA). The results were expressed as a z score in relation to age and sex. Immunosuppression was achieved by using triple therapy: azathioprine, cyclosporine A and prednisolone. At the time of the DEXA, 59% of the patients were on daily steroid treatment and 41% on alternate-day treatment. RESULTS: All patients presented bone mass losses with a maximal decrease between 5 and 21 months post-transplantation and a posterior tendency to recovery. Fifty percent of the children had severe osteopenia (bone mineral density < -1 SD). There was no statistically significant association between the severity of bone loss and values of ionized calcium, phosphorus, intact PTH, or calcitriol received. However, a linear correlation was found between cumulative steroid dose and osteopenia (r = -0.35, p < 0.05). Height and growth velocity were more affected in the severe osteopenia group. In this group, the proportion of children on daily steroid treatment was statistically higher (72% vs 45%, p < 0.05). CONCLUSIONS: Bone densitometry is an accurate, rapid and noninvasive method to measure renal transplant impact on the growing skeleton and it must be done in a periodic and standardized way.