Nonadherence after pediatric renal transplantation: detection and treatment.

PURPOSE OF REVIEW: Nonadherence is a problem in adolescents and young adults. Risk factors are classified as those of the individual, family, health-care-system, or community. I present the latest reports and how to tackle nonadherence. RECENT FINDINGS: Nonadherence risk is independent of one's origin in a high-poverty or low-poverty neighborhood or having private or public insurance in respect to African Americans. Females with male grafts have higher graft-failure risks than do males. Female recipients aged 15-24 with grafts from female donors have higher graft-failure risk than do males. In study of nonadherence risks, such findings must be taken into account. Antibody-mediated rejection is seen in nonadherence. The sirolimus and tacrolimus coefficient of variation is associated with nonadherence, donor-specific antibodies, and rejection. Adolescents had electronically monitored compliance reported by e-mail, text message or visual dose reminders and meetings with coaches. These patients had significantly greater odds of taking medication than did controls. Transition programs have an impact on renal function and rejection episodes. SUMMARY: Individual risk factors are many, and methods for measuring nonadherence exist. Each transplant center should have a follow-up program to measure nonadherence, especially in adolescence, and a transition program to adult care.

Renal function after combined liver-kidney transplantation: A longitudinal study of pediatric and adult patients.

It has been proposed that the liver protects the kidney in CLKT. However, few studies have examined long-term renal function after CLKT and contrasted renal function of CLKT patients to KT patients beyond one year after transplantation. We studied long-term renal function of CLKT patients and compared renal function of CLKT patients to KT patients between one and five years after transplantation. Patients who underwent CLKT between 1993 and 2011 were included (n = 34; 11 children and 23 adults). Ninety-six (27 children and 69 adults) KT patients were selected as controls. GFR was estimated (eGFR) and measured (mGFR) with 51 Cr-EDTA clearance. Mean mGFR was 63 at one and 70 at ten years after pediatric CLKT. Mean eGFR was 75 at one and 50 at ten years after adult CLKT. Difference in mean mGFR between pediatric CLKT and KT patients was 8 (95% CI -7 to 23) and 11 (95% CI -4 to 26) at one and five years after transplantation, respectively. Difference in mean eGFR between adult CLKT and KT patients was 8 (95% CI -5 to 20) and 1 (95% CI -10 to 12) at one and five years after transplantation, respectively. Longitudinal changes in GFRs were somewhat similar in CLKT and KT patients in both age-groups but pediatric CLKT patients had on average higher GFRs than pediatric KT patients. In long-term follow-up, renal function remains stable in pediatric CLKT patients but declines in adult CLKT patients.

Infants Requiring Maintenance Dialysis: Outcomes of Hemodialysis and Peritoneal Dialysis.

BACKGROUND: The impact of different dialysis modalities on clinical outcomes has not been explored in young infants with chronic kidney failure. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: Data were extracted from the ESPN/ERA-EDTA Registry. This analysis included 1,063 infants 12 months or younger who initiated dialysis therapy in 1991 to 2013. FACTOR: Type of dialysis modality. OUTCOMES & MEASUREMENTS: Differences between infants treated with peritoneal dialysis (PD) or hemodialysis (HD) in patient survival, technique survival, and access to kidney transplantation were examined using Cox regression analysis while adjusting for age at dialysis therapy initiation, sex, underlying kidney disease, and country of residence. RESULTS: 917 infants initiated dialysis therapy on PD, and 146, on HD. Median age at dialysis therapy initiation was 4.5 (IQR, 0.7-7.9) months, and median body weight was 5.7 (IQR, 3.7-7.5) kg. Although the groups were homogeneous regarding age and sex, infants treated with PD more often had congenital anomalies of the kidney and urinary tract (CAKUT; 48% vs 27%), whereas those on HD therapy more frequently had metabolic disorders (12% vs 4%). Risk factors for death were younger age at dialysis therapy initiation (HR per each 1-month later initiation, 0.95; 95% CI, 0.90-0.97) and non-CAKUT cause of chronic kidney failure (HR, 1.49; 95% CI, 1.08-2.04). Mortality risk and likelihood of transplantation were equal in PD and HD patients, whereas HD patients had a higher risk for changing dialysis treatment (adjusted HR, 1.64; 95% CI, 1.17-2.31). LIMITATIONS: Inability to control for unmeasured confounders not included in the Registry database and missing data (ie, comorbid conditions). Low statistical power because of relatively small number of participants. CONCLUSIONS: Despite a widespread preconception that HD should be reserved for cases in which PD is not feasible, in Europe, we found 1 in 8 infants in need of maintenance dialysis to be initiated on HD therapy. Patient characteristics at dialysis therapy initiation, prospective survival, and time to transplantation were very similar for infants initiated on PD or HD therapy.

Donor-specific antibodies after pediatric liver transplantation: a cross-sectional study of 50 patients.

The role of donor-specific HLA antibodies (DSAs) after pediatric liver transplantation (LT) is inadequately established. We conducted a cross-sectional study on the prevalence of DSAs and their association with liver histology and biochemical variables after pediatric LT. Serum samples were drawn for HLA antibody analyses from 50 patients (76% of 66 eligible patients) operated on at age <18 years between 1987 and 2007 with a median of 10.0 (interquartile range 4.0-16.4) years after deceased donor LT. Mixed and single-antigen beads with Luminex were used for HLA antibody screening and detection. A mean fluorescence intensity (MFI) value of 1000 was used for positive cutoff. Twenty-six patients (52%; 95% confidence interval (CI) 39% to 65%) had DSAs. In 22 (85%) patients, DSAs were against class II HLA antigens with a mean (standard deviation) MFI of 13,481 (4727). The unadjusted prevalence ratio for portal inflammation in DSA-positive compared to DSA-negative patients (n = 47; 9/24 vs. 1/23) was 8.6 (95% CI 1.6 to 50.9). Laboratory values at the time of study were comparable between DSA-positive and DSA-negative patients. In conclusion, approximately half of patients studied had DSAs after pediatric LT. Portal inflammation was associated with DSA positivity although the wide confidence interval around the ratio estimate warrants cautious interpretation.

Renal transplantation in infants.

Renal transplantation (RTx) has become an accepted mode of therapy in infants with severe renal failure. The major indications are structural abnormalities of the urinary tract, congenital nephrotic syndrome, polycystic diseases, and neonatal kidney injury. Assessment of these infants needs expertise and time as well as active treatment before RTx to ensure optimal growth and development, and to avoid complications that could lead to permanent neurological defects. RTx can be performed already in infants weighing around 5 kg, but most operations occur in infants with a weight of 10 kg or more. Perioperative management focuses on adequate perfusion of the allograft and avoidance of thrombotic and other surgical complications. Important long-term issues include rejections, infections, graft function, growth, bone health, metabolic problems, neurocognitive development, adherence to medication, pubertal maturation, and quality of life. The overall outcome of infant RTx has dramatically improved, with long-term patient and graft survivals of over 90 and 80 %, respectively.

Timing of renal replacement therapy does not influence survival and growth in children with congenital nephrotic syndrome caused by mutations in NPHS1: data from the ESPN/ERA-EDTA Registry.

BACKGROUND: Congenital nephrotic syndrome (CNS) of the Finnish type, NPHS1, is the most severe form of CNS. Outcomes of renal replacement therapy (RRT) in NPHS1 patients in Europe were analysed using data from the ESPN/ERA-EDTA Registry. As NPHS1 is most prevalent in Finland and the therapeutic approach differs from that in many other countries, we compared outcomes in Finnish and other European patients. METHODS: NPHS1 mutations were confirmed in 170 children with CNS who initiated RRT (dialysis or renal transplantation) between 1991 and 2012. Finnish (n = 66) and non-Finnish NPHS1 patients (n = 104) were compared with respect to treatment policy, age at first RRT and renal transplantation (RTX), patient and graft survival, estimated glomerular filtration rate (eGFR) and growth. Age-matched patients with congenital anomalies of the kidney and urinary tract (CAKUT) served as controls. RESULTS: Finnish NPHS1 patients were significantly younger than non-Finnish patients, both at the start of RRT and at the time of RTX. We found similar overall 5-year patient survival on RRT (91 %) and graft survival (89 %) in both NPHS1 groups and CAKUT controls. At the start of RRT, height standard deviation score (SDS) was higher in Finnish patients than in non-Finnish patients (mean [95 % CI]: -1.31 [-2.13 to -0.49] and -3.0 [-4.22 to -1.91], p < 0.01 respectively), but not at 5 years of age. At 5 years of age height and body mass index (BMI) SDS were similar to those of CAKUT controls. CONCLUSIONS: Overall, 5-year patient and graft survival of both Finnish and non-Finnish NPHS1 patients on RRT were excellent and comparable with CAKUT patients with equally early RRT onset and was independent of the timing of RRT initiation and RTX.

Late hepatic artery thrombosis after pediatric liver transplantation: a cross-sectional study of 34 patients.

Hepatic artery thrombosis (HAT) after liver transplantation (LT) increases patient morbidity and mortality. Early HAT is considered to occur within the first month after LT, whereas late HAT occurs after the first month. Few studies have addressed late HAT after LT, especially in pediatric patients. Between 1987 and 2007, 99 patients (age < 18 years) underwent deceased donor LT. Thirty-four of 66 eligible patients (52%) underwent magnetic resonance imaging (MRI) according to protocol. On the basis of MRI findings, the patients were grouped as those who experienced late HAT and those who did not. Additionally, potential risk factors for late HAT were analyzed retrospectively. P values were adjusted for multiplicity. The median age at LT was 1.7 years [interquartile range (IQR) = 1.0-9.6 years], and the median follow-up time at MRI was 9.5 years (IQR = 4.0-16.4 years). Late HAT was diagnosed in 15 of the 34 patients [44%, 95% confidence interval (CI) = 29%-61%] undergoing MRI and in 3 of these patients with angiography preceding MRI. Ultrasonography revealed late HAT in 6 of these 15 patients with a sensitivity of 40% (95% CI = 20%-64%). The donor/recipient weight ratio remained significantly higher for the patients with late HAT versus the patients without late HAT after P values were adjusted (5.4 versus 1.9, P = 0.03). No marked differences were observed in laboratory or liver histology parameters between the groups. In conclusion, late HAT is common after pediatric LT. The donor/recipient weight ratio was higher for patients with late HAT, and this was attributable to the lower weight of the recipients. No salient features of late HAT were observed with respect to laboratory or histological parameters, at least in terms of our study's cross-sectional period.

Congenital nephrotic syndrome and recurrence of proteinuria after renal transplantation.

Renal transplantation (RTx) is the only curative treatment for most cases of congenital and infantile nephrotic syndrome (NS) caused by genetic defects in glomerular podocyte proteins. The outcome of RTx in these children is usually excellent, with no recurrence of nephrotic syndrome. A subgroup of patients with the Finnish type of congenital nephrosis (CNF), shows, however, a clear risk for post-RTx proteinuria. Most of these patients have a homozygous truncating mutation (Fin-major mutation) in the nephrin gene (NPHS1), leading to total absence of the major podocyte protein, nephrin. After RTx, these patients develop anti-nephrin antibodies resulting in nephrotic range proteinuria. Plasma exchange combined with cyclophosphamide and anti-CD20 antibodies has proved to be successful therapy for these episodes. NS recurrence has also occurred in a few patients with mutations in the podocin gene (NPHS2). No anti-podocin antibodies have been detectable, and the pathophysiology of the recurrence remains open. While most of these episodes have resolved, the optimal therapy remains to be determined.

Parent-child and spousal relationships in families with a young child with end-stage renal disease.

BACKGROUND: End-stage renal disease (ESRD) leads to the need for dialysis and renal transplantation (Tx). Peritoneal dialysis (PD) of young children is normally performed at home by the parents and affects the whole family. We studied the coping of families with a young child with ESRD by interviewing the parents of 19 children. METHODS: The spousal and parent-child relationships were assessed by using the Psychosocial Assessment of Childhood Experiences (PACE) and the Brief Measure of Expressed Emotion, respectively. A control group of 22 families with a healthy child was used for the parent-child relationship evaluation. RESULTS: The spousal relationship at the start of PD was good or fairly good in most of the families and remained good in half of the families following renal Tx. Lack of support from close relatives and renal Tx were associated with a poorer relationship quality. Almost all parents expressed much or fairly much emotional warmth towards the child throughout the study, but there was a trend towards increased criticism over time. No differences in the degree of expressed warmth or criticism were noted between the index parents and controls. CONCLUSIONS: Overall, the study families appeared to cope well despite the serious illness of their child and the demands of the treatments.

A time-to-event model for acute rejections in paediatric renal transplant recipients treated with ciclosporin A.

AIMS: Ciclosporin A (CsA) dosing in immunosuppression after paediatric kidney transplantation remains challenging, and appropriate target CsA exposures (AUCs) are controversial. This study aimed to develop a time-to-first-acute rejection (AR) model and to explore predictive factors for therapy outcome. METHODS: Patient records at the Children's Hospital in Helsinki, Finland, were analysed. A parametric survival model in NONMEM was used to describe the time to first AR. The influences of AUC and other covariates were explored using stepwise covariate modelling, bootstrap-stepwise covariate modelling and cross-validated stepwise covariate modelling. The clinical relevance of the effects was assessed with the time at which 90% of the patients were AR free (t90). RESULTS: Data from 87 patients (0.7-19.8 years old, 54 experiencing an AR) were analysed. The baseline hazard was described with a function changing in steps over time. No statistically significant covariate effects were identified, a finding substantiated by all methods used. Thus, within the observed AUC range (90% interval 1.13-8.40 h mg l⁻¹), a rise in AUC was not found to increase protection from AR. Dialysis time, sex and baseline weight were potential covariates, but the predicted clinical relevance of their effects was low. For the strongest covariate, dialysis time, median t90 was 5.8 days (90% confidence interval 5.1-6.8) for long dialysis times (90th percentile) and 7.4 days (6.4-11.7) for short dialysis times (10th percentile). CONCLUSIONS: A survival model with discrete time-varying hazards described the data. Within the observed range, AUC was not identified as a covariate. This feedback on clinical practice may help to avoid unnecessarily high CsA dosing in children.

Risk factors for impaired quality of life and psychosocial adjustment after pediatric heart, kidney, and liver transplantation.

Few studies compare HRQOL and PSA in children who have undergone different types of solid organ Tx. In this cross-sectional study, HRQOL and PSA were assessed in 74 Tx patients (16 heart, 44 kidney, 14 liver) at a mean age of 11.5 (range 6.3-16.7), 7.2 yr post-Tx (range 1.0-15.0). HRQOL was self-assessed using standardized health utility questionnaires (15D-17D). The patients' PSA was evaluated using the Child Behavior Checklist for parents, Youth Self-Report for patients aged 11-16 yr, and Teacher Report Form. Outcomes did not differ significantly between Tx groups. Preadolescents (8-11 yr) reported poorer HRQOL compared with same-age peers (p = 0.020). In contrast, adolescents reported similar HRQOL and PSA compared to the general population. Proxy-reports revealed more PSA problems compared with age expectations (p < 0.01), mainly in internalizing behavior (p < 0.01). Lower HRQOL was associated with shorter follow-up time since Tx, congenital disease, and a psychiatric or neurological diagnosis. PSA problems were associated with family-related variables, neurological diagnosis, shorter follow-up time, and in teacher-reports longer disease duration before Tx. Different pediatric Tx groups have similar outcome. Neurological comorbidity and shorter follow-up time are important risk factors, but the impact of family-related variables on PSA indicate the need of family interventions.

Mutations in SPINT2 cause a syndromic form of congenital sodium diarrhea.

Autosomal-recessive congenital sodium diarrhea (CSD) is characterized by perinatal onset of a persistent watery diarrhea with nonproportionally high fecal sodium excretion. Defective jejunal brush-border Na(+)/H(+) exchange has been reported in three sporadic patients, but the molecular basis of the disease has not been elucidated. We reviewed data from a large cohort of CSD patients (n = 24) and distinguished CSD associated with choanal or anal atresia, hypertelorism, and corneal erosions--i.e., a syndromic form of CSD--occurring in ten families from an isolated form--i.e., classic CSD--presenting in seven families. Patients from both groups have a high risk of mortality due to immediate electrolyte imbalances and complications from long-term parenteral nutrition in the first years of life, but survivors can eventually adapt to partial or complete enteral nutrition. A genome-wide SNP scan was applied and identified a homozygous c.593-1G-->A splicing mutation in SPINT2, encoding a Kunitz-type serine-protease inhibitor, in one extended kindred with syndromic CSD. The same mutation and four distinct, homozygous or compound heterozygous mutations (p.Y163C, c.1A-->T, c.337+2T-->C, c.553+2T-->A) were identified in all syndromic patients. No SPINT2 mutations were found in classic-CSD patients. SPINT2 mutations were associated with loss of protein synthesis or failure to inhibit the serine protease trypsin in vitro. We delineate syndromic CSD as a distinct disease entity caused by SPINT2 loss-of-function mutations. SPINT2 mutations might lead to an excess of yet unknown serine protease activity in affected tissues.

Neuropsychological profile of children with kidney transplants.

BACKGROUND: Varying results on the cognitive outcome of children who have undergone kidney transplantation (KTx) have raised concern for specific neurocognitive difficulties. METHODS: Fifty children with KTx were assessed at a mean age of 11.1 (SD 3.2; range 6.3-16.4), on average 6.9 (SD 3.6; range 1.0-14.1) years post-operatively. A standardized test of intelligence [Wechsler Intelligence Scale for Children (WISC-III)] and neuropsychological tests from NEPSY-II were administered. The neuropsychological profile of KTx children was compared to that of a control group matched for gender, age and maternal education. RESULTS: The KTx children had a lower intelligence quotient (83.9) than the test norms (100.0, P < 0.001). On neuropsychological assessment, the KTx group scored generally lower than the control group did (P < 0.001). The difference was evident in both the verbal and visuospatial domains, on a sub-test of complex auditory attention, verbal working memory and facial affect recognition. When children with neurological co-morbidity were excluded, the remaining group still scored lower than the controls did on Comprehension of Instructions (P = 0.06), Design Copying (P = 0.007) and Affect Recognition (P = 0.018). A better cognitive outcome was mainly associated with the absence of neurological co-morbidity, younger age, shorter disease duration and sustained kidney function. Children with congenital nephrosis had a similar outcome to those with other diagnoses. CONCLUSIONS: KTx children exhibit a pattern of effects in their cognitive outcome in which both the visuospatial and language domains are affected, but visual memory and simple auditory attention remain intact. Patients without neurological co-morbidity exhibit impairment in receptive language, visuospatial functions and in recognizing emotional states.

Update on SLC26A3 mutations in congenital chloride diarrhea.

Congenital chloride diarrhea (CLD) is an autosomal recessive disorder with around 250 cases reported so far. Life-long secretory diarrhea is caused by mutations in the solute carrier family 26 member 3 (SLC26A3) gene disrupting the epithelial Cl(-) /HCO 3- transport in the ileum and colon. Although salt substitution allows favorable outcome, possible manifestations include renal impairment, intestinal inflammation, and male infertility. At least 55 mutations, of which 21 (38%) novel are reported here, cause CLD. Majority of the mutations are single nucleotide substitutions (n = 30; 55%) with 18 missense, 7 nonsense, and 5 splice-site mutations. Additional mutations are minor deletions/insertions or their combinations (n = 21; 38%), major deletions (n = 3; 5%), and a major insertion (n = 1; 2%). Distinct founder mutations appear in Finland, Poland, and Arab countries, whereas patients from other countries carry rare homozygous or compound heterozygous mutations. None of the studied SLC26A3 mutants shows significant Cl(-) /HCO 3- exchange activity in vitro, and accordingly, evidence of genotype-phenotype differencies remain nonexistent. The domain interaction between SLC26A3 and the cystic fibrosis transmembrane conductance regulator (CFTR) raises a possibility of CFTR modulation in the pathogenesis of CLD. This review summarizes the current knowledge of SLC26A3 mutations and polymorphisms, and their biological and clinical relevance.

Long-term risk of end stage renal disease in patients with posterior urethral valves.

PURPOSE: Congenital obstructive uropathy can lead to end stage renal disease. Progression to end stage renal disease in childhood is well described but long-term prognosis in adulthood has not been thoroughly investigated. In this study we evaluated the risk of end stage renal disease in patients with posterior urethral valves. MATERIALS AND METHODS: During 1953 to 2003 a total of 200 male patients were treated for posterior urethral valves at our institution and of these 193 could be followed for renal outcome. Followup data on patients treated with dialysis or kidney transplantation were collected from patient records and the Finnish Kidney Transplantation Registry, and data on deceased patients were collected from hospital records and the Finnish Population Register Centre. RESULTS: Median patient age at evaluation was 31 years (range 6 to 69). Of the 193 patients followed 44 (22.8%) had progression to end stage renal disease. According to a Kaplan-Meier analysis the lifetime risk of end stage renal disease was 28.5% (SE 3.8%). No patient had end stage renal disease after the age of 34 years. The lowest serum creatinine value during postoperative year 1 was associated with speed of progression to end stage renal disease. Early presentation, pneumothorax, bilateral vesicoureteral reflux and recurrent urinary tract infections after the abolition of urethral obstruction were associated with an increased risk of end stage renal disease at followup. CONCLUSIONS: Congenital obstructive uropathy can lead to end stage renal disease during childhood or young adulthood. However, the risk of end stage renal disease seems to decrease eventually. Poor kidney function at presentation is associated with worse renal prognosis.

Visuospatial impairment in children and adolescents after liver transplantation.

A minority of children with liver transplants exhibit significant delay in global intelligence; others have specific learning disabilities. More specific data on neurocognitive strengths and weaknesses are lacking. Eighteen children aged 7-16 yr, who had undergone LTx in Finland participated in the study. They were assessed on an average 7.6 (s.d. 4.5, range 1.0-15.0) years post-operatively at a mean age of 11.8 (s.d. 3.1, range 7.2-16.1). A standardized test of intelligence (WISC-III), a neuropsychological test battery (NEPSY-II), and a parental questionnaire on the child's development (FTF) were administered. The neuropsychological test profile of the LTx group was compared with that of a matched control group of healthy children. The LTx children achieved on an average normal FSIQ 94.0 and VIQ 99.6. Their Performance Intelligence Quotient (PIQ 88.9, p=0.043) was, however, significantly lower than the population mean. On neuropsychological assessment, the LTx children scored generally lower than the control group (p=0.004), a difference significant in sub-tests assessing visuospatial and visuoconstructive functions and social perception. No differences emerged in sub-tests of attention and executive functions, memory and learning, or language functions. LTx children are at increased risk for impairment in the visuospatial domain.

Nucleotide sequence of the Na+/H+ exchanger-8 in patients with congenital sodium diarrhea.

Sodium absorption by the intestine is mediated by brush border Na/H exchangers, which include the NHE3 and NHE8 isoforms. We demonstrated a maturational decrease in NHE8 and increase in NHE3 in mouse intestine mRNA abundance and brush border membrane protein abundance, indicating a developmental switch of isoforms. Congenital sodium diarrhea is a rare autosomal recessive disorder characterized by polyhydramnios, hyponatremia, metabolic acidosis, and diarrhea with a high sodium content. Previous studies using intestinal brush border membrane vesicles from patients with this disorder have demonstrated a decrease in Na/H exchanger activity. Because some patients with congenital sodium diarrhea improve with age and knowing the developmental switch from NHE8 to NHE3, NHE8 may be a candidate gene for this disorder. We sequenced NHE8 from 5 patients with this disorder and found no disease-causing homozygous mutations. Although brush border membrane Na/H exchange activity may be decreased, exonic mutations in NHE8 cannot account for this disorder in these subjects.

Neurological development in 21 children on peritoneal dialysis in infancy.

Few studies have focused on the neurodevelopment of infants on peritoneal dialysis (PD). Infants are the most demanding patient group on PD and thus are vulnerable to neurological sequelae. We studied 21 patients <2 years of age (mean 0.59 years) at onset of PD. They were evaluated by a neurologist, otologist, physiotherapist, and occupational therapist during PD. Neuropsychological tests were collected from all patients at least 5 years old, and the brain images were reviewed. Eleven patients (52%) had a pre- or neonatal problem or comorbidity as risk factor for their development at onset of PD. All infants tolerated PD well. At the end of the study, 71% had some neurological abnormality, 29% a major impairment (all with predialysis risk factors), and 43% a minor one. Brain infarcts were detected in four patients (19%) and other ischemic lesions in three (14%). Three patients (14%) developed hearing defect. Mortality rate was 5%. PD is a safe treatment modality for end-stage renal failure in infants. Some patients had risk factors for development, but their neurological problems did not progress during PD. Patients without risk factors tolerated PD well without major neurological sequelae.

[Congenital nephrotic syndrome of the Finnish type--key to the mechanisms of proteinuria]. / Suomalaistyyppinen synnynnäinen nefroosi--avain proteinurian mekanismeihin.

Congenital nephrotic syndrome of the Finnish type is a serious renal disease belonging to the Finnish disease heritage. It appears as substantial proteinuria, hypoproteinemia and edema in a newborn. Kidney transplantation is the only effective treatment. The cause of the disease is a mutation in the gene encoding the nephrin protein. Nephrin is produced by the epithelial cell (podocyte) of the glomerulus. It is expressed in the slit membrane connecting the pedicles of the podocyte. This finding has revolutionized the concept of glomerular filtration and set off active research on the pathogenetic mechanisms of proteinuria.

Association of Renal Glomerular and Tubular Function With Renal Outcome in Patients With Posterior Urethral Valves.

OBJECTIVE: To analyze renal glomerular and tubular function and their association in patients operated for posterior urethral valves and to prognosticate the risk for end-stage kidney disease (ESKD) METHODS: Sixty-three previously treated patients were evaluated for renal function during 1987-1991. The patients' age at evaluation was 11 years (range 2-24). Glomerular function was assessed by measuring glomerular filtration rate (GFR) and urine albumin excretion. Tubular function was determined by measuring urine concentration capacity and excretion of electrolytes (Na, K, Cl, Ca, P, Mg) and ß-2-microglobulin. Additionally, the prevalence of hypertension and serum parathyroid hormone and aldosterone values were registered. Tubular function was compared with GFR and the risk of developing ESKD before November 2018. RESULTS: Twenty of the study patients (32%) had decreased GFR. In addition, 19% had proteinuria and 56% were hypertensive. Those without proteinuria or hypertension had better GFR values (P < .01 for both). There was a significant correlation between GFR and all the tubular function (P < .05) variables (except excretion of chloride) measured. Compared to the patients with favorable renal outcome, the patients (n = 10) who later developed ESKD had significantly (P < .01) lower GFR and reduced urinary excretion of all measured electrolytes except calcium. Consistently, urine ß-2 microglobulin and serum parathyroid hormone and aldosterone values were significantly higher in the patients who developed ESKD (P ≤ .01). CONCLUSION: Both glomerular and tubular function decline was common and several parameters were likely to predict ESKD in posterior urethral valves patients.