PROGRESS STUDY: Progression of chronic kidney disease in children and heat shock proteins

Various molecular and cellular processes are involved in renal fibrosis, such as oxidative stress, inflammation, endothelial cell injury, and apoptosis. Heat shock proteins (HSPs) are implicated in the progression of chronic kidney disease (CKD). Our aim was to evaluate changes in urine and serum HSP levels over time and their relationships with the clinical parameters of CKD in children. In total, 117 children with CKD and 56 healthy children were examined. The CKD group was followed up prospectively for 24 months. Serum and urine HSP27, HSP40, HSP47, HSP60, HSP70, HSP72, and HSP90 levels and serum anti-HSP60 and anti-HSP70 levels were measured by ELISA at baseline, 12 months, and 24 months. The urine levels of all HSPs and the serum levels of HSP40, HSP47, HSP60, HSP70, anti-HSP60, and anti-HSP70 were higher at baseline in the CKD group than in the control group. Over the months, serum HSP47 and HSP60 levels steadily decreased, whereas HSP90 and anti-HSP60 levels steadily increased. Urine HSP levels were elevated in children with CKD; however, with the exception of HSP90, they decreased over time. In conclusion, our study demonstrates that CKD progression is a complicated process that involves HSPs, but they do not predict CKD progression. The protective role of HSPs against CKD may weaken over time, and HSP90 may have a detrimental effect on the disease course.

Comparison of Preoperative and Postoperative Anterior Segment Measurements with Pentacam in Horizontal Muscle Surgery

Purpose

To evaluate the effect of horizontal muscle surgery (recession or recession plus resection) on the anterior chamber parameters in patients after strabismus surgery. Patients and Methods. The Scheimpflug of 18 eyes of 12 patients with horizontal deviations were recorded just before surgery and 1 month after surgery. The power of anterior surface of cornea in horizontal and vertical axis, thinnest corneal thickness, anterior chamber depth, anterior chamber volume, and cornea volume were analyzed. The clinical characteristics of patients, the size of the deviations, the surgical doses, and observed responses to surgery were reviewed.

Results

There were six male and six female patients with an average age of 11.4 years (range, 4 to 22 years). Mean preoperative deviation was 47.91 PD (range, 20 to 75 PD), eight patients had esotropia with 57.5 PD average deviation (range, 40 to 75 PD), and four patients had exotropia with 28.75 PD average deviation (range, 20 to 35 PD). Of these 18 eyes, 12 eyes had horizontal muscle recession and 6 eyes had recession plus resection surgery. At the end of 1 month, three patients were orthophoric and eight patients had residual deviations varying between 16 and 35 PD. Preoperative and postoperative comparison of the whole study group documented insignificant changes in anterior chamber parameters and in keratometer readings. However, after dividing patients into two groups–recession or recession plus resection group–only one parameter, anterior chamber volume, was significantly reduced in recession plus resection group.

Conclusions

Patients with strabismus who undergo recession plus resection procedure are prone to change in anterior chamber volume. Study with larger groups and long follow-up is necessary for clearer documentation of alterations at anterior chamber parameters.

Urine heat shock protein 70 levels as a marker of urinary tract infection in children

BACKGROUND

Heat shock proteins (HSPs) are a multi-family group of proteins which are upregulated by the cell in response to exposure to hazardous (stress) factors, including infectious agents, to prevent changes in protein structure. The aim of our study was to assess whether urine levels of the 70-kDa family of HSPs (HSP70s) increase in children with urinary tract infection (UTI) and to determine the optimal urine (u) HSP70 cut-off level to predict UTI in children.

METHODS

Forty patients with symptomatic UTI (UTI group), 30 healthy children (control group), 21 asymptomatic patients with proven bacterial contamination in their urine culture (contamination group) and 30 patients with fever caused by other infections (non-UTI infection group) were enrolled in the study. Random urine samples were obtained for measurement of HSP70 and creatinine (Cr) from all groups. Urine was collected prior to the treatment of UTI at the time of presentation and after treatment. Urine HSP70 levels were measured by enzyme-linked immunosorbent analysis. A dimercaptosuccinic acid (DMSA) scan was performed at 5-7 days after presentation in UTI group to distinguish patients with acute pyelonephritis from those with cystitis; based on this scan, no patients had acute pyelonephritis. Patients were classified with pyelonephritis in the presence of all of the following signs: axillary fever of ≥39 °C, leukocytosis and positivity for C-reactive protein.

RESULTS

The mean urine HSP70:Cr ratio (uHSP70/Cr) prior to treatment was significantly higher in the UTI group (449.86 ± 194.33 pg/mg) than in the control, contamination and non-UTI infection groups (39.93 ± 47.61, 32.43 ± 9.09 and 45.14 ± 19.76, respectively; p = 0.0001). Using a cut-off of 158 pg/mg uHSP70/Cr for the prediction of UTI, the sensitivity and specificity of the assay were 100 and 100 %, respectively (area under the time-concentration curve = 1). The uHSP70/Cr was highest in the patients with clinical pyelonephritis (p = 0.001). Mean uHSP70/Cr after treatment decreased to 60.68 ± 51.11 pg/mg in UTI group (p = 0 .0001).

CONCLUSIONS

Our findings suggest that elevated uHSP70/Cr may be a useful biomarker for the prediction of UTI in children, with a high sensitivity and specificity, and that they may help to distinguish UTI from other infections as well as bacterial contamination of the urine.

Higher urine heat shock protein 70/creatinine ratio in type 1 diabetes mellitus

Insidious progressive renal damage caused by type 1 diabetes mellitus (T1DM) begins in childhood before it becomes manifest in adult ages. Heat shock proteins (HSPs) regulate the cell response to any hazardous factors to prevent cell structure. The aim of the study is to determine whether urine levels of HSPs increase in diabetic children with time and indicate a progressive renal injury in T1DM. Thirty-three patients with T1DM and 24 healthy children were enrolled in the study. Renal function was normal in all patients. Urine levels of HSP27, HSP40, HSP60, HSP70, and HSP90 were measured by enzyme-linked immunosorbent assay at two consecutive years (2012 and 2013). The results were evaluated as urine HSP/creatinine ratios (uHSP/Cr). Mean urine HSP27/Cr, HSP40/Cr, HSP60/Cr, HSP70/Cr, HSP90/Cr in patient group were significantly higher than in controls in 2012 (uHSP27/Cr 460.12 ± 217.64 versus 270.02 ± 136.83 pg/mgCr; uHSP40/Cr 180.89 ± 118.59 versus 99.44 ± 62.49 pg/mgCr; uHSP60/Cr 114.40 ± 64.91 versus 70.50 ± 43.70 pg/mgCr; uHSP70/Cr 41.17 ± 28.42 versus 16.47 ± 7.32 pg/mgCr; uHSP90/Cr 175.64 ± 102.22 versus 107.61 ± 75.85 pg/mgCr) (p < 0.05). In 2013, uHSP70/Cr level increased significantly (51.08 ± 27.72 pg/mgCr; p = 0.001), whereas uHSP60/Cr level decreased and uHSP27/Cr, uHSP40/Cr, uHSP90/Cr levels remained stable (p > 0.05). Area under the curve (AUC) for uHSP70/Cr (0.957) was significantly higher than the others. Using a cutoff 22.59 pg/mgCr for uHSP70/Cr to predict of diabetic damage, sensitivity and specificity were 85% and 96%, respectively. Our results suggest that uHSP70/Cr increases over time and may indicate early phases of progressive kidney damage in diabetic children.

ADCK4-Associated Glomerulopathy Causes Adolescence-Onset FSGS

Hereditary defects of coenzyme Q10 biosynthesis cause steroid-resistant nephrotic syndrome (SRNS) as part of multiorgan involvement but may also contribute to isolated SRNS. Here, we report 26 patients from 12 families with recessive mutations in ADCK4. Mutation detection rate was 1.9% among 534 consecutively screened cases. Patients with ADCK4 mutations showed a largely renal-limited phenotype, with three subjects exhibiting occasional seizures, one subject exhibiting mild mental retardation, and one subject exhibiting retinitis pigmentosa. ADCK4 nephropathy presented during adolescence (median age, 14.1 years) with nephrotic-range proteinuria in 44% of patients and advanced CKD in 46% of patients at time of diagnosis. Renal biopsy specimens uniformly showed FSGS. Whereas 47% and 36% of patients with mutations in WT1 and NPHS2, respectively, progressed to ESRD before 10 years of age, ESRD occurred almost exclusively in the second decade of life in ADCK4 nephropathy. However, CKD progressed much faster during adolescence in ADCK4 than in WT1 and NPHS2 nephropathy, resulting in similar cumulative ESRD rates (>85% for each disorder) in the third decade of life. In conclusion, ADCK4-related glomerulopathy is an important novel differential diagnosis in adolescents with SRNS/FSGS and/or CKD of unknown origin.

Relationship between clinical findings and genetic mutations in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is one of the most frequent genetic diseases encountered in the Mediterranean region. We aimed to investigate the correlation between genetic mutations and the clinical findings in 562 patients with FMF.

METHODS

In this retrospective cross-sectional study conducted with patients' files between 2006, and 2013, reverse hybridization assay for MEFV gene mutations was used and the 12 most frequent mutations were screened. Mutation types and clinical findings were compared with variance analysis.

RESULTS

The mean age was 6.9 ± 3.4 years (range, 1.8-11.6 years). The most common symptom was fever (97.3%). Thirty-four of the patients (6.04%) were admitted with periodic fever only. Of these patients, M694V was the most common mutation type (73.5%). The percentage of the patients predominantly presenting with recurrent abdominal pain was 77.78% and the most frequent mutations were M694V and E148Q. The rate of arthritis and arthralgia was significantly higher in patients with M694V and E148Q mutations. Chest pain was reported more often in patients homozygous for M694V (61.4%). Pericardial effusion was documented in the echocardiography of 10.9% of the 229 children with chest pain. Some patients had both FMF and Henoch Schönlein purpura (HSP), and were more likely to harbor either homozygote M694V or E148Q mutations. The frequency of episodes was higher in patients with homozygous M694V mutations (number of attacks = 4.4 ± 1.6/month). Proteinuria was detected in 106 patients of cases (29.2%), at an average of 854 ± 145 mg/L. Most of the patients with proteinuria and elevated serum amyloid-A had homozygous M694V mutation.

CONCLUSION

The most common mutation in children in Turkey with FMF is the M694V mutation. Recurrent abdominal pain, arthritis or arthralgia, chest pain, and pericarditis were commonly seen in patients with M694V and E148Q mutations.

Development of a medication adherence scale for familial Mediterranean fever (MASIF) in a cohort of Turkish children

OBJECTIVES

To develop and assess the validity and reliability of an adherence scale concerning medical treatment in paediatric FMF patients.

METHODS

The Medication Adherence Scale in FMF Patients (MASIF) is a 18-item questionnaire that evaluates adherence to medication in four domains. Validation of the instrument was accomplished in paediatric FMF patients (aged 2-18 years) under medication at least for 6 months. The first step was to build up the scale through qualitative approach (with interviews using semi-structured questions). Validation analyses included assessment of feasibility, face and content validity; construct validity, internal consistency and test-retest reliability.

RESULTS

One hundred and fifty patients with FMF were enrolled in the study. The mean age of the patients was 11.11±4.02 years and 48.7% of them were male. The MASIF was found to be feasible and valid for both face and content. It correlated with the Morisky Medication Adherence Scale as a gold standard thereby demonstrating good construct validity (r=0.515, p<0.001). Assessment of content validity identified four subscales. The internal consistency, Cronbach's alpha was 0.728. There was a positive and significant correlation between test and retest scores (r=0.843; p<0.001). Also, a significant correlation between parents' and children's reports (r=0.781, p<0.001).

CONCLUSIONS

Based on these results, the use of this scale to assess and follow up the adherence to treatment in paediatric FMF patients under medical treatment is recommended.

Isokinetic Evaluation of Knee Extensor/Flexor Muscle Strength in Behcet's Patients

BACKGROUND

Behçet's disease (BD) is an idiopathic, multisystemic, progressive disease. The purpose of this study is to compare the knee flexor and extensor isokinetic muscle strengths of Behcet's patients with that of healthy subjects.

METHODS

Twenty-five (13 male and 12 female) patients with BD and 25 (15 male and 10 female) healthy individuals were included in the study. Velocities of 90°/sec, 120°/sec, and 150°/sec were used for the isokinetic muscle strength testing. Patients with active inflammatory knee arthritis were excluded. Peak torque (Nm) and peak torque adjusted to body weight (%) were taken into consideration for comparison between study groups.

RESULTS

Compared to healthy controls, there was a statistically significant decrease in both the bilateral knee extensor and flexor muscle isokinetic peak torques(Nm) as well as the peak torques adjusted to body weight (%) at velocities of 90°/sec, 120°/sec and 150°/sec in patients with BD (p < 0.05). However, there was no significant difference in the agonist-antagonist ratio of the isokinetic peak torques of knee muscles between the two groups.

CONCLUSION

In light of these findings, we have concluded that both knee flexor and extensor isokinetic muscle strengths are lower in BD. We therefore recommend careful monitoring of patients with BD in terms of muscle strength.

Clinical importance of renal calyceal microlithiasis in children

BACKGROUND

Renal calyceal microlithiasis refers to a hyperechogenic spot in renal calyces <3 mm in diameter detected on renal sonography. These spots possibly represent the first step in calculus formation. The aim of this study was to analyze the clinical presentation, predisposing factors, prognosis and clinical importance of these hyperechogenic spots in renal calyces, renal calyceal microlithiasis, during childhood.

METHODS

The data of 292 children (135 girls, 157 boys) with microlithiasis diagnosed between January 1998 and December 2010 were evaluated retrospectively. Demographic data, serum biochemistry, urinary metabolic factors, and renal sonography results were obtained from patient files. A total of 228 patients were re-evaluated at least 6 months after the first observation of renal calyceal microlithiasis and at 6-12 month intervals thereafter.

RESULTS

Mean age was 16.8 ± 14.9 months, and mean follow-up duration was 14.6 ± 5.9 months. Presenting symptoms were abdominal or flank pain (41.1%), hematuria (35.6%), dysuria (24.7%) and urinary tract infection (34.6%). Previous ultrasounds were normal in 35% of the children. Metabolic and anatomic abnormalities were found in 55.5% and 17.8%, respectively. Hypercalciuria was the most common metabolic abnormality (88.9%). Among 228 patients who had been re-evaluated, microlithiasis disappeared in 37.7%; decreased in number or size in 23.7%; progressed to renal stone formation in 10.6%; increased in number of microlithiasis in 19.0%; and remained unchanged on radiology in 9.0%.

CONCLUSION

Renal calyceal microlithiasis represents a spectrum of clinical situations and underlying metabolic abnormalities that need further investigation in children.

Genetic screening in adolescents with steroid-resistant nephrotic syndrome

Genetic screening paradigms for congenital and infantile nephrotic syndrome are well established; however, screening in adolescents has received only minor attention. To help rectify this, we analyzed an unselected adolescent cohort of the international PodoNet registry to develop a rational screening approach based on 227 patients with nonsyndromic steroid-resistant nephrotic syndrome aged 10-20 years. Of these, 21% had a positive family history. Autosomal dominant cases were screened for WT1, TRPC6, ACTN4, and INF2 mutations. All other patients had the NPHS2 gene screened, and WT1 was tested in sporadic cases. In addition, 40 sporadic cases had the entire coding region of INF2 tested. Of the autosomal recessive and the sporadic cases, 13 and 6%, respectively, were found to have podocin-associated nephrotic syndrome, and 56% of them were compound heterozygous for the nonneutral p.R229Q polymorphism. Four percent of the sporadic and 10% of the autosomal dominant cases had a mutation in WT1. Pathogenic INF2 mutations were found in 20% of the dominant but none of the sporadic cases. In a large cohort of adolescents including both familial and sporadic disease, NPHS2 mutations explained about 7% and WT1 4% of cases, whereas INF2 proved relevant only in autosomal dominant familial disease. Thus, screening of the entire coding sequence of NPHS2 and exons 8-9 of WT1 appears to be the most rational and cost-effective screening approach in sporadic juvenile steroid-resistant nephrotic syndrome.

Evaluation of total oxidant and antioxidant status in localized and generalized vitiligo

BACKGROUND

Vitiligo is an acquired depigmentation disorder, and oxidative stress is suggested to have a major role in its aetiopathogenesis.

AIM

To assess whether oxidative stress has a greater role in generalized than in localized vitiligo.

METHODS

We assessed 31 patients with active vitiligo (17 localized, 14 generalized) and 38 healthy controls. Serum total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) were determined.

RESULTS

Patients with vitiligo had significantly lower TAS and higher TOS and OSI values than controls. Both localized and generalized vitiligo were associated with lower TAS and higher TOS and OSI values, compared with controls, and all three did not differ with vitiligo type.

CONCLUSIONS

A systemic oxidative stress exists in patients with vitiligo. These results indicate that the global antioxidant capacity of patients might have been exhausted through a defence mechanism against oxidative processes. The imbalance in TOS/TAS status may have an important role in the aetiopathogenesis of vitiligo, regardless of the clinical variant of the disease.

Human monoclonal antibody MBL-HCV1 delays HCV viral rebound following liver transplantation: a randomized controlled study

Rapid allograft infection complicates liver transplantation (LT) in patients with hepatitis C virus (HCV). Pegylated interferon-α and ribavirin therapy after LT has significant toxicity and limited efficacy. The effect of a human monoclonal antibody targeting the HCV E2 glycoprotein (MBL-HCV1) on viral clearance was examined in a randomized, double-blind, placebo-controlled pilot study in patients infected with HCV genotype 1a undergoing LT. Subjects received 11 infusions of 50 mg/kg MBL-HCV1 (n=6) or placebo (n=5) intravenously with three infusions on day of transplant, a single infusion on days 1 through 7 and one infusion on day 14 after LT. MBL-HCV1 was well-tolerated and reduced viral load for a period ranging from 7 to 28 days. Median change in viral load (log10 IU/mL) from baseline was significantly greater (p=0.02) for the antibody-treated group (range -3.07 to -3.34) compared to placebo group (range -0.331 to -1.01) on days 3 through 6 posttransplant. MBL-HCV1 treatment significantly delayed median time to viral rebound compared to placebo treatment (18.7 days vs. 2.4 days, p<0.001). As with other HCV monotherapies, antibody-treated subjects had resistance-associated variants at the time of viral rebound. A combination study of MBL-HCV1 with a direct-acting antiviral is underway.

Management of anemia in children receiving chronic peritoneal dialysis

Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.

Circulating suPAR in two cohorts of primary FSGS

Overexpression of soluble urokinase receptor (suPAR) causes pathology in animal models similar to primary FSGS, and one recent study demonstrated elevated levels of serum suPAR in patients with the disease. Here, we analyzed circulating suPAR levels in two cohorts of children and adults with biopsy-proven primary FSGS: 70 patients from the North America-based FSGS clinical trial (CT) and 94 patients from PodoNet, the Europe-based consortium studying steroid-resistant nephrotic syndrome. Circulating suPAR levels were elevated in 84.3% and 55.3% of patients with FSGS patients in the CT and PodoNet cohorts, respectively, compared with 6% of controls (P<0.0001); inflammation did not account for this difference. Multiple regression analysis suggested that lower suPAR levels associated with higher estimated GFR, male sex, and treatment with mycophenolate mofetil. In the CT cohort, there was a positive association between the relative reduction of suPAR after 26 weeks of treatment and reduction of proteinuria, with higher odds for complete remission (P=0.04). In the PodoNet cohort, patients with an NPHS2 mutation had higher suPAR levels than those without a mutation. In conclusion, suPAR levels are elevated in geographically and ethnically diverse patients with FSGS and do not reflect a nonspecific proinflammatory milieu. The associations between a change in circulating suPAR with different therapeutic regimens and with remission support the role of suPAR in the pathogenesis of FSGS.

The relationship between oxidative stress, smoking and the clinical severity of psoriasis

BACKGROUND

Recent studies suggested that increased oxidant products and decreased antioxidant system functions may be involved in the pathogenesis of psoriasis. In this study, we investigated total oxidative status, Paraoxonase (PON)1/arylesterase enzyme activities and severity of the disease in smoker and non-smoker psoriatic patients.

METHODS

Fifty-four patients with plaque type psoriasis (28 smokers and 26 non-smokers) and 62 healthy volunteers (16 smokers and 46 non-smokers) were enrolled in the study. Serum total oxidant status (TOS), total antioxidant capacity (TAC) and arylesterase levels were measured, and oxidative stress index (OSI) was calculated in all participants.

RESULTS

Psoriasis Area and Severity Index scores were significantly higher in smoker patients than in non-smoker patients (P = 0.014). Both smoker and non-smoker patients had significantly increased TOS levels and OSI values and decreased TAC levels than healthy subjects (all P values = 0.000). The TAC and TOS levels, OSI values and arylesterase activities were similar between smoker and non-smoker patients. The levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) were not significantly different between smoker and non-smoker psoriasis patients. When compared with non-smoking controls, only smoking psoriasis patients had significantly higher TG (P = 0.005), lower HDL (P = 0.022) and lower arylesterase levels (P = 0.015). There were no significant correlations with Psoriasis Area and Severity Index (PASI) scores and TAC, TOS, OSI, TG, TC, HDL and LDL levels in all psoriasis patients.

CONCLUSIONS

Oxidative stress is increased in psoriasis patients regardless of their smoking status. The decreased arylesterase activity in smoker psoriasis patients suggested that smoking may be a considerable risk factor that increases the severity of psoriasis by increasing oxidative stress in these patients.

Brucella infection with pancytopenia after pediatric liver transplantation

Brucellosis is considered the most widespread zoonosis in the world. It has been reported that the prevalence of seropositivity among the Turkish population varies from 3% to 14%. We present a case of brucellosis after pediatric liver transplantation. A 15-year-old boy with the diagnosis of neuro Wilson's disease underwent deceased-donor liver transplantation. The postoperative immunosuppressive protocol consisted of steroids and tacrolimus. Two months after the operation the patient experienced fever to 40°C. The patient complained of poor appetite, headache, and diarrhea. He had had pancytopenia. Despite administration of appropriate antibiotics, antiviral and antifungal agents, fever persisted for > 1 month. Multiple blood, urine, stool, and sputum cultures were negative. Bone marrow aspirate revealed hypocellularity. Liver biopsy was performed, but rejection was not observed on biopsy specimen. Brucella serology was positive and Brucella agglutination titer was 1:320. Bone marrow culture was positive for Brucella but blood culture was negative. The patient was then treated with oral doxycycline and rifampin for 8 weeks. No previous case report about Brucella infection after liver transplantation has appeared in the literature, to our knowledge; our case is presented as the first. Bone marrow hypoplasia is a rare feature of Brucella infection. Our patient with brucellosis and pancytopenia had had hypocellular bone marrow. The clinical and hematologic findings resolved with treatment of the infection. Brucella infection should be suspected in liver transplanted recipients with fever of unknown origin, especially in a recipient who has lived in an endemic area. Brucella also should be considered as a possible diagnosis in patients with pancytopenia.

Anti-lymphocyte therapy successfully controls late "cholestatic" rejection in pediatric liver transplant recipients

Rejection is independently associated with liver graft loss in children. We report the successful rescue of grafts using ATG+/-OKT3 in late rejection associated with cholestasis. Retrospective chart review was performed after IRB approval. Between 2003 and 2010, 14 pediatric liver transplant recipients received anti-lymphocyte treatment for "cholestatic" rejection. Median age at transplantation was 12.7 yr (range 0.9-23.4), eight were boys, and immunosuppression was tacrolimus based. Median time from transplantation to rejection was five yr (range 1.1-10.5). Median peak total bilirubin was 11.1 mg/dL (range 1.4-18). All showed moderate to severe acute rejection and hepatocellular cholestasis on histology. ATG/OKT3 was started as first-line therapy in six and in the remaining eight as second-line therapy after failure of pulse steroids. Thirteen responded with normalization of aminotransferases and bilirubin, median time 16 wk (range 7-112); one non-adherent recipient has still not achieved normal graft function at last follow-up. Patient survival is 100%, with no re-transplantation and no post-transplant lymphoproliferative disease, median follow-up 2.9 yr (range 1.1-7.2). Cholestasis associated with acute rejection occurring late after liver transplantation may herald steroid resistance. First-line therapy with anti-lymphocyte preparations, prophylactic anti-microbial therapy, and close monitoring allow excellent rates of patient and graft survival.

Combined liver kidney transplantation: critical analysis of a single-center experience

Combined liver kidney transplantation (LKT) can be successfully performed on patients with liver and renal failure; however, outcomes are inferior to liver transplantation alone (OLT). Our aim was to determine the indications for and outcome of LKT and whether patients with longer wait times required more frequent LKT versus OLT alone. We included 18/93 adults who underwent LKT from August 2007 to August 2010 for hepatitis C virus (HCV, n = 7), alcohol (n = 5), nonalcoholic steatohepatitis (n = 2), primary biliary sclerosis, polycystic kidney disease with liver involvement, hepatic adenomatosis, and ischemic hepatitis. Eleven were originally listed for LKT and 7 required listing for-kidney transplantation while awaiting OLT. Eight were on dialysis when first listed and 10 had a low glomerular filtration rate or known kidney disease. The mean calculated Model for End-Stage Liver Disease (MELD) score for LKT was 31.2 ± 3.54. Seven had hepatocellular carcinoma in explants. Two patients had acute cellular kidney rejection that responded to treatment. Recurrence of HCV was documented in 5 patients within 6 months of LKT; 2/5 received HCV therapy (interferon and ribavirin) without renal allograft rejection. One-year liver graft/patient survival was 94% after LKT. One patient died at 6 months post LKT due to severe HCV recurrence. Last mean serum creatinine level was 1.35 ± 0.28 mg/dL for LKT patients. LKT is a safe procedure with favorable outcomes even in patients with a high MELD score. Transplantation of patients with a high MELD score due to regional variations in organ allocation results in additional use of kidneys by OLT patients. Improved organ allocation algorithms in OLT would help to reduce combined transplants, sparing more kidneys.

Split liver transplantation: an overview

Liver transplantation (OLT) has become the only treatment modality for patients with end-stage liver diseases. Establishment of standard liver transplantation technique, development of better immunosuppressive medications and accumulated experience using them safely, and improvement of intensive care and anesthesia played major role to have current 88%-90% 1-year survival after liver transplantation. As liver transplantations became more successful with the growing experience and development in the field, the increased demand for liver allografts could not match the available supply of donor organs. As a result of this imbalance, each year nearly 3000 patients die in the United States awaiting liver transplantation on the national waiting list. Split liver transplantation (SLT) has been perceived as an important strategy to increase the supply of liver grafts by creating 2 transplants from 1 allograft. The bipartition of a whole liver also carries utmost importance by increasing the available grafts for the pediatric patients, where size-matched whole liver allografts are scarce, leading increased incidence of waiting list mortality in this group. In the common approach of the split liver procedure, liver is divided into a left lateral segment graft (LLS) to be transplanted to a child and a right extended liver lobe graft for an adult recipient. In a technically more challenging variant of this procedure, the principle is to split the liver into 2 hemigrafts and use the left side for a small adult or a teenager and the right for a medium-sized adult patient. Donor selection for splitting, technical expertise in both OLT and hepatobiliary surgery, logistics to decrease total ischemia time, and manpower of the transplantation team are important factors for successful outcomes after SLT. The liver can be split on the back table (ex situ) or in the donor hospital before the donor cross-clamp using in situ splitting technique, which was developed directly from living donor liver transplantation. The most important advantage of in situ splitting is to decrease the total ischemia time and increased the possibility of inter-center sharing. The in situ technique of splitting has other advantages, including evaluation of the viability of segment IV in case of LLS splitting and better control of bleeding from cut surface upon reperfusion on the recipient. Recipient selection for split liver grafts is also crucial for success after SLT. In this review, we aim to summarize the advances that have occurred in SLT. We also discuss anatomic and technical aspects, including both approaches to SLT, which is now considered by many centers to be a routine operation.

MYO1E mutations and childhood familial focal segmental glomerulosclerosis

BACKGROUND

Focal segmental glomerulosclerosis is a kidney disease that is manifested as the nephrotic syndrome. It is often resistant to glucocorticoid therapy and progresses to end-stage renal disease in 50 to 70% of patients. Genetic studies have shown that familial focal segmental glomerulosclerosis is a disease of the podocytes, which are major components of the glomerular filtration barrier. However, the molecular cause in over half the cases of primary focal segmental glomerulosclerosis is unknown, and effective treatments have been elusive.

METHODS

We performed whole-genome linkage analysis followed by high-throughput sequencing of the positive-linkage area in a family with autosomal recessive focal segmental glomerulosclerosis (index family) and sequenced a newly discovered gene in 52 unrelated patients with focal segmental glomerulosclerosis. Immunohistochemical studies were performed on human kidney-biopsy specimens and cultured podocytes. Expression studies in vitro were performed to characterize the functional consequences of the mutations identified.

RESULTS

We identified two mutations (A159P and Y695X) in MYO1E, which encodes a nonmuscle class I myosin, myosin 1E (Myo1E). The mutations in MYO1E segregated with focal segmental glomerulosclerosis in two independent pedigrees (the index family and Family 2). Patients were homozygous for the mutations and did not have a response to glucocorticoid therapy. Electron microscopy showed thickening and disorganization of the glomerular basement membrane. Normal expression of Myo1E was documented in control human kidney-biopsy specimens in vivo and in glomerular podocytes in vitro. Transfection studies revealed abnormal subcellular localization and function of the A159P-Myo1E mutant. The Y695X mutation causes loss of calmodulin binding and of the tail domains of Myo1E.

CONCLUSIONS

MYO1E mutations are associated with childhood-onset, glucocorticoid-resistant focal segmental glomerulosclerosis. Our data provide evidence of a role of Myo1E in podocyte function and the consequent integrity of the glomerular filtration barrier.

Methylenetetrahydrofolate reductase C677T polymorphism in patients with Henoch-Schönlein purpura

AIM

Associations between several vascular diseases such as Kawasaki disease, venous and arterial thromboembolism, cardiovascular disease, diabetic nephropathy, focal segmental glomerulosclerosis and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism have been reported. This is a clinical study designed to investigate the possible effects of MTHFR C677T polymorphism on the development of Henoch-Schönlein purpura (HSP).

METHODS

Forty-one patients with HSP (25 male/16 female) with a mean age of 7.8 ± 2.9 years were included in the study. The control group consisted of 50 healthy children. MTHFR genotypes were determined by polymerase chain reaction and by Hindf I restriction enzyme analysis and subsequent 3% agarose gel electrophoresis techniques.

RESULTS

No significant differences were observed in the distribution of MTHFR genotypes or allele frequencies in the HSP cases versus controls. Plasma homocysteine levels and vitamin B(12) levels were almost comparable in the HSP patients and control group without a significant difference. Folic acid levels were within normal limits in the HSP cases and the control group, HSP patients' levels being significantly higher than the control group. No significant relationship was present with the MTHFR genotype and plasma homocysteine, vitamin B(12) and folic acid levels in HSP patients.

CONCLUSION

No association with MTHFR gene polymorphism and homocysteine plasma levels could be found in patients with HSP. The results of this study indicate that other mechanisms should be operative in the development of HSP.

Gain in visual acuity after cataract surgery improves postural stability and mobility

OBJECTIVES

Vision plays an important role in postural stability. It has also been shown that visual information from the environment and visual cues significantly contribute to balance skills. The aim of this study was to investigate the effects of visual acuity on postural stability and mobility before and after cataract surgery.

METHODS

The study group was composed of 25 male and 11 female patients (age 57-84, mean 66.6 +/- 4.7) who had been operated for age-related cataract. Postural stability and mobility were assessed before and four weeks after the surgery by means of Biodex stability system (BSS), Tinetti, Time up and go (TUG) and Functional reach (FR) tests, as well as by gait analysis (gait velocity, step length, step width, cadence, stride length).

RESULTS

Postoperative visual acuity was significantly improved. Gait velocity and cadence increased significantly but step length, stride length, and step width did not change significantly. Postoperative improvement of Tinetti balance, TUG and FR tests were significant. Similarly, antero-posterior stability index (APSI), mediolateral stability index (MLSI) and overall stability index (OSI) that were examined with BSS improved significantly after the cataract surgery.

CONCLUSION

These results demonstrated that gain in visual acuity after cataract surgery improves the postural stability and mobility of patients (Tab. 2, Fig. 1, Ref. 29). Full Text in free PDF www.bmj.sk.

Post-transplant glucose status in 61 pediatric renal transplant recipients: preliminary results of five Turkish pediatric nephrology centers

To assess the incidence, risk factors and outcomes of PTDM, a total of 61 non-diabetic children (24 girls, 37 boys, age: 14.5 +/- 2.1 yr) were examined after their first kidney transplantation (37.3 +/- 21.6 months) with an OGTT. At baseline, 16 (26.2%) patients had IGT, 45 (73.8%) had NGT, and no patient had PTDM. No significant difference was shown between TAC- and CSA-treated patients in terms of IGT. Higher BMI z-scores (p = 0.011), LDL-cholesterol (p < 0.05) and triglyceride levels (p < 0.01), HOMA-IR (p = 0.013) and lower HOMA-%beta (p = 0.011) were significantly associated with IGT. Fifty-four patients were re-evaluated after six months; eight patients with baseline IGT (50%) improved to NGT, three (19%) developed PTDM requiring insulin therapy, five (31%) remained with IGT, and four patients progressed from NGT to either IGT (two) or PTDM (two). These 12 progressive patients had significantly higher total cholesterol (p < 0.05), triglycerides (p < 0.05), HOMA-IR (p < 0.01) and lower HOMA-%beta (p < 0.0) than non-progressive patients at baseline. We can conclude that post-transplantation glucose abnormalities are common in Turkish pediatric kidney recipients, and higher BMI z-scores and triglyceride concentrations are the main risk factors. Considering that the progressive patients are significantly more insulin resistant at baseline, we suggest that the utility of both HOMA-IR and HOMA-%beta in predicting future risk of PTDM and/or IGT should be evaluated in children.

Functional analysis of BMP4 mutations identified in pediatric CAKUT patients

Human congenital anomalies of the kidney and urinary tract (CAKUT) represent the major causes of chronic renal failure (CRF) in children. This set of disorders comprises renal agenesis, hypoplasia, dysplastic or double kidneys, and/or malformations of the ureter. It has recently been shown that mutations in several genes, among them BMP4, are associated with hereditary renal developmental diseases. In BMP4, we formerly identified three missense mutations (S91C, T116S, N150K) in five pediatric CAKUT patients. These BMP4 mutations were subsequently studied in a cellular expression system, and here we present functional data demonstrating a lower level of messenger RNA (mRNA) abundance in Bmp4 mutants that indicates a possible negative feedback of the mutants on their own mRNA expression and/or stability. Furthermore, we describe the formation of alternative protein complexes induced by the S91C-BMP4 mutation, which results in perinuclear endoplasmic reticulum (ER) accumulation and enhanced lysosomal degradation of Bmp4. This work further supports the role of mutations in BMP4 for abnormalities of human kidney development.

Effect of paraoxonase 1 gene polymorphisms on clinical course of Henoch-Schönlein purpura

BACKGROUND

Henoch-Schönlein purpura (HSP) is a systemic vasculitis; its pathogenesis is still unknown. Oxidative stress may play a role in the pathogenesis of HSP. Paraoxonase1 (PON1) is an antioxidant enzyme. Two polymorphisms have been defined in the coding region of the PON1 gene, Q/R192 and L/M55. In the present study, we aimed to investigate the effect of PON1 gene polymorphisms on the course and renal involvement of HSP in Turkish children.

METHOD

Forty-six patients with HSP were compared with 34 healthy children regarding the distribution of PON1 polymorphisms.

RESULTS

PON1 Q/R192 genotype distribution was 58.6% QQ, 32.6% QR and 8.8% RR in the HSP group and 14.3% QQ, 50% QR and 35.7% RR in the control group. The frequency of QQ genotype was higher in the HSP group, and the presence of QQ genotype increased the risk by 3.42-fold for developing HSP (p=0.000, Fisher exact test; odds ratio [OR] = 2.048; 95% confidence interval [95% CI], 1.396-3.00). PON1 L/M55 genotype distribution was 50% LL, 43.5% LM and 6.5% MM in the HSP group and 48% LL, 26% LM and 26% MM in the control group. The frequency of MM genotype was lower in the HSP group, and the presence of MM genotype decreased the risk by 7.38-fold for developing HSP (p=0.009, Fisher exact test; OR=7.380, 95% CI, 1.474-36.953).

CONCLUSION

PON1 polymorphisms may contribute to the pathogenesis and course of HSP, but we suggest that further investigations with larger patient groups are required to confirm our results.

Strict blood-pressure control and progression of renal failure in children

BACKGROUND

Although inhibition of the renin-angiotensin system delays the progression of renal failure in adults with chronic kidney disease, the blood-pressure target for optimal renal protection is controversial. We assessed the long-term renoprotective effect of intensified blood-pressure control among children who were receiving a fixed high dose of an angiotensin-converting-enzyme (ACE) inhibitor.

METHODS

After a 6-month run-in period, 385 children, 3 to 18 years of age, with chronic kidney disease (glomerular filtration rate of 15 to 80 ml per minute per 1.73 m(2) of body-surface area) received ramipril at a dose of 6 mg per square meter of body-surface area per day. Patients were randomly assigned to intensified blood-pressure control (with a target 24-hour mean arterial pressure below the 50th percentile) or conventional blood-pressure control (mean arterial pressure in the 50th to 95th percentile), achieved by the addition of antihypertensive therapy that does not target the renin-angiotensin system; patients were followed for 5 years. The primary end point was the time to a decline of 50% in the glomerular filtration rate or progression to end-stage renal disease. Secondary end points included changes in blood pressure, glomerular filtration rate, and urinary protein excretion.

RESULTS

A total of 29.9% of the patients in the group that received intensified blood-pressure control reached the primary end point, as assessed by means of a Kaplan-Meier analysis, as compared with 41.7% in the group that received conventional blood-pressure control (hazard ratio, 0.65; confidence interval, 0.44 to 0.94; P=0.02). The two groups did not differ significantly with respect to the type or incidence of adverse events or the cumulative rates of withdrawal from the study (28.0% vs. 26.5%). Proteinuria gradually rebounded during ongoing ACE inhibition after an initial 50% decrease, despite persistently good blood-pressure control. Achievement of blood-pressure targets and a decrease in proteinuria were significant independent predictors of delayed progression of renal disease.

CONCLUSIONS

Intensified blood-pressure control, with target 24-hour blood-pressure levels in the low range of normal, confers a substantial benefit with respect to renal function among children with chronic kidney disease. Reappearance of proteinuria after initial successful pharmacologic blood-pressure control is common among children who are receiving long-term ACE inhibition. (ClinicalTrials.gov number, NCT00221845.)

Effect of ischemia-reperfusion on the incidence of acute cellular rejection and timing of histologic hepatitis C virus recurrence after liver transplantation

BACKGROUND

Because of a critical shortage of deceased donor (DD) livers, more extended criteria allografts are being utilized; these allografts are at increased risk for ischemia-reperfusion injury (IRI). We assessed whether, in a large cohort of patients transplanted for hepatitis C virus (HCV) either via a DD or live donor (LD), there was a relationship between the degree of IRI and the frequency and timing of acute cellular rejection (ACR) and histologic HCV recurrence.

METHODS

During an 8-year study, patients were separated into four groups based on peak alanine aminotransferase (ALT) levels and three groups based on severity of IRI on postreperfusion liver biopsy.

RESULTS

The mean follow-up time of 433 DD and 44 LD recipients was 1212 days. We noted a strong correlation in DD between peak ALT and the histologic degree of IRI (P = .01). There was no difference in the incidence or grade of ACR among the four groups. There was no correlation between the severity of IRI and the incidence or time to histologic recurrence of HCV.

CONCLUSIONS

The magnitude of peak ALT correlated with the severity of IRI on postreperfusion liver biopsy. Among this large HCV cohort, there was no correlation between the severity of IRI and the incidence or timing of histologic HCV recurrence or incidence of ACR.

Improving adherence to medications in pediatric liver transplant recipients

We describe results from a clinical program, which aimed at improving adherence to medications in children who had a liver transplant. We followed the medical outcomes of 23 children and adolescents who participated in a clinical adherence-improvement protocol during the years 2001-2002. The protocol included identification of non-adherent patients by examining tacrolimus blood levels and intervention by increasing the frequency of clinic visits for non-adherent patients. In the two-yr preintervention (1999-2000), there was no improvement in any of the outcomes. After the intervention, the number of patients with high alanine aminotransferase levels (100 and above) decreased significantly, from eight before the intervention to four afterwards. Other outcomes, including the number of rejection episodes (three before, none after) and the degree of adherence to tacrolimus, also improved, but the improvement did not reach statistical significance. Although non-adherent patients were called to clinic more often under the protocol, the intervention did not lead to increased outpatient costs. This adherence--improvement intervention appears to be promising in improving outcomes in pediatric liver transplant recipients. Larger, controlled studies are needed to establish the efficacy of this or other approaches.

SIX2 and BMP4 mutations associate with anomalous kidney development

Renal hypodysplasia (RHD) is characterized by reduced kidney size and/or maldevelopment of the renal tissue following abnormal organogenesis. Mutations in renal developmental genes have been identified in a subset of affected individuals. Here, we report the first mutations in BMP4 and SIX2 identified in patients with RHD. We detected 3 BMP4 mutations in 5 RHD patients, and 3 SIX2 mutations in 5 different RHD patients. Overexpression assays in zebrafish demonstrated that these mutations affect the function of Bmp4 and Six2 in vivo. Overexpression of zebrafish six2.1 and bmp4 resulted in dorsalization and ventralization, respectively, suggesting opposing roles in mesendoderm formation. When mutant constructs containing the identified human mutations were overexpressed instead, these effects were attenuated. Morpholino knockdown of bmp4 and six2.1 affected glomerulogenesis, suggesting specific roles for these genes in the formation of the pronephros. In summary, these studies implicate conserved roles for Six2 and Bmp4 in the development of the renal system. Defects in these proteins could affect kidney development at multiple stages, leading to the congenital anomalies observed in patients with RHD.

Once-daily tacrolimus extended-release formulation: 1-year post-conversion in stable pediatric liver transplant recipients

The pharmacokinetics, safety and tolerability of a once-daily formulation of tacrolimus (tacrolimus extended-release formulation; XL formerly referred to as MR or MR4) were assessed in 18 stable pediatric liver transplant recipients who were converted from the twice-a-day formulation of tacrolimus (TAC) to XL. Patients received their twice-a-day dose of TAC on study days 1 through 7. Beginning on the morning of study day 8, patients were converted to XL on a 1:1 (mg:mg) basis for their total daily dose, and were maintained on a once-daily AM dosing regimen using the same therapeutic monitoring and patient care techniques employed with TAC. Based on pharmacokinetic profiles obtained on study days 7 (TAC) and 14 (XL), steady state exposure (AUC(0-24)) was equivalent between XL and TAC; the mean XL/TAC ratio for lnAUC(0-24) was 100.9% (90% CI: 90.8%, 112.1%). AUC(0-24) and C(min) were strongly correlated at steady state (correlation coefficient: XL 0.90, TAC 0.94). During the first year post-conversion, there were no cases of acute rejection, discontinuation of XL, graft loss or death. The safety profile of XL was consistent with that known for TAC. These results support the safe and convenient conversion of pediatric liver transplant recipients from twice-a-day TAC to once-daily XL.

Is paraoxonase 192 gene polymorphism a risk factor for membranoproliferative glomerulonephritis in children?

We investigated the effects of paraoxonase (PON1) 192 polymorphism on serum PON1 activity and the impact of phenotypic expression on the risk and prognosis of Turkish children with membranoproliferative glomerulonephritis (MPGN). Eighteen children with biopsy-proven Type I MPGN (10 boys, 8 girls) and age-matched 53 healthy controls were included in the study. PCR (polymerase chain reaction), RFLP (restriction fragment length polymorphism) and agarose gel electrophoresis techniques were used to determine the PON1 192 genotype. PON1 activity was measured by spectrophotometric assay of p-nitrophenol production following addition of paraoxon. We found that PON1 192 genotype distribution (AA, AB, BB) in MPGN patients were 61.1%, 22.3%, 16.6% and 15.1%, 35.8%, 49.1% in controls, respectively. The frequency of AA genotypes was significantly higher in the MPGN group (0.611) compared with the healthy controls (0.151) (p < 0.001). Although the serum PON1 activity was lower in MPGN patients (103.3 +/- 55.2 U/l) than the healthy controls (130.9 +/- 71.2 U/mol), the difference was not statistically significant (p = 0.0563). In the genotypes of patients and controls classified according to PON1 A/B polymorphism; serum PON1 activities were significantly increased (p < 0.001, ANOVA) in the order of PON1 AA, AB and BB in both MPGN patients (82.4, 91.7 and 173.6 U/l) and healthy controls (85.9, 119.9 and 193.1 U/l), respectively. There was a significant relationship between the poor prognosis and having AA genotype and low PON1 activity. Of the 8 patients with poor prognosis, 7 had genotype AA and the remaining one was AB heterozygote. Our results suggest that homozygosity for the A allele might have an important role on the risk for developing MPGN and may also be associated with the poor prognosis of disease. In conclusion, we suggest that the PON1 activities are affected by PON1 genetic variability in Turkish patients with MPGN.

Crescentic glomerulonephritis in a child with infective endocarditis

Renal manifestations associated with infective endocarditis (IE) may present with different clinical patterns, and the most common renal histopathological finding is diffuse proliferative and exudative type of glomerulonephritis, leading to hematuria and/or proteinuria. Renal failure due to crescentic glomerulonephritis (CGN) in children with IE is a very rare condition. We report here a 6-year-old boy, who had a history of cardiac surgery for pulmonary atresia and ventricular septal defect, presenting with the clinical findings of IE and hematuria associated with renal failure due to CGN. He was treated with a combination of intravenous (IV) methylprednisolone pulses and appropriate antibiotics, but also received one dose of IV cyclophosphamide. Complete serological, biochemical, and clinical improvement was achieved after 2 months of follow-up. Antibiotic therapy is the essential part of the treatment of IE-associated glomerulonephritis; however, this case also highlights the importance of aggressive immunosuppressive therapy to suppress the immunological process related with infection in this life-threatening condition leading to renal failure.